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3961 lines
92 KiB
3961 lines
92 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* event tracer |
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* |
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* Copyright (C) 2008 Red Hat Inc, Steven Rostedt <[email protected]> |
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* |
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* - Added format output of fields of the trace point. |
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* This was based off of work by Tom Zanussi <[email protected]>. |
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* |
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*/ |
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|
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#define pr_fmt(fmt) fmt |
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|
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#include <linux/workqueue.h> |
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#include <linux/security.h> |
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#include <linux/spinlock.h> |
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#include <linux/kthread.h> |
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#include <linux/tracefs.h> |
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#include <linux/uaccess.h> |
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#include <linux/module.h> |
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#include <linux/ctype.h> |
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#include <linux/sort.h> |
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#include <linux/slab.h> |
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#include <linux/delay.h> |
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#include <trace/events/sched.h> |
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#include <trace/syscall.h> |
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#include <asm/setup.h> |
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#include "trace_output.h" |
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|
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#undef TRACE_SYSTEM |
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#define TRACE_SYSTEM "TRACE_SYSTEM" |
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DEFINE_MUTEX(event_mutex); |
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LIST_HEAD(ftrace_events); |
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static LIST_HEAD(ftrace_generic_fields); |
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static LIST_HEAD(ftrace_common_fields); |
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static bool eventdir_initialized; |
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#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO) |
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static struct kmem_cache *field_cachep; |
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static struct kmem_cache *file_cachep; |
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static inline int system_refcount(struct event_subsystem *system) |
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{ |
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return system->ref_count; |
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} |
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static int system_refcount_inc(struct event_subsystem *system) |
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{ |
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return system->ref_count++; |
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} |
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static int system_refcount_dec(struct event_subsystem *system) |
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{ |
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return --system->ref_count; |
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} |
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/* Double loops, do not use break, only goto's work */ |
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#define do_for_each_event_file(tr, file) \ |
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list_for_each_entry(tr, &ftrace_trace_arrays, list) { \ |
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list_for_each_entry(file, &tr->events, list) |
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|
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#define do_for_each_event_file_safe(tr, file) \ |
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list_for_each_entry(tr, &ftrace_trace_arrays, list) { \ |
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struct trace_event_file *___n; \ |
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list_for_each_entry_safe(file, ___n, &tr->events, list) |
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|
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#define while_for_each_event_file() \ |
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} |
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static struct ftrace_event_field * |
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__find_event_field(struct list_head *head, char *name) |
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{ |
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struct ftrace_event_field *field; |
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list_for_each_entry(field, head, link) { |
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if (!strcmp(field->name, name)) |
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return field; |
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} |
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|
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return NULL; |
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} |
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struct ftrace_event_field * |
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trace_find_event_field(struct trace_event_call *call, char *name) |
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{ |
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struct ftrace_event_field *field; |
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struct list_head *head; |
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|
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head = trace_get_fields(call); |
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field = __find_event_field(head, name); |
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if (field) |
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return field; |
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field = __find_event_field(&ftrace_generic_fields, name); |
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if (field) |
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return field; |
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return __find_event_field(&ftrace_common_fields, name); |
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} |
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static int __trace_define_field(struct list_head *head, const char *type, |
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const char *name, int offset, int size, |
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int is_signed, int filter_type) |
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{ |
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struct ftrace_event_field *field; |
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field = kmem_cache_alloc(field_cachep, GFP_TRACE); |
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if (!field) |
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return -ENOMEM; |
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field->name = name; |
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field->type = type; |
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if (filter_type == FILTER_OTHER) |
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field->filter_type = filter_assign_type(type); |
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else |
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field->filter_type = filter_type; |
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field->offset = offset; |
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field->size = size; |
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field->is_signed = is_signed; |
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list_add(&field->link, head); |
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return 0; |
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} |
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int trace_define_field(struct trace_event_call *call, const char *type, |
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const char *name, int offset, int size, int is_signed, |
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int filter_type) |
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{ |
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struct list_head *head; |
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|
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if (WARN_ON(!call->class)) |
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return 0; |
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head = trace_get_fields(call); |
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return __trace_define_field(head, type, name, offset, size, |
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is_signed, filter_type); |
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} |
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EXPORT_SYMBOL_GPL(trace_define_field); |
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#define __generic_field(type, item, filter_type) \ |
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ret = __trace_define_field(&ftrace_generic_fields, #type, \ |
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#item, 0, 0, is_signed_type(type), \ |
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filter_type); \ |
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if (ret) \ |
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return ret; |
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#define __common_field(type, item) \ |
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ret = __trace_define_field(&ftrace_common_fields, #type, \ |
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"common_" #item, \ |
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offsetof(typeof(ent), item), \ |
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sizeof(ent.item), \ |
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is_signed_type(type), FILTER_OTHER); \ |
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if (ret) \ |
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return ret; |
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static int trace_define_generic_fields(void) |
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{ |
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int ret; |
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|
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__generic_field(int, CPU, FILTER_CPU); |
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__generic_field(int, cpu, FILTER_CPU); |
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__generic_field(char *, COMM, FILTER_COMM); |
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__generic_field(char *, comm, FILTER_COMM); |
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return ret; |
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} |
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static int trace_define_common_fields(void) |
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{ |
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int ret; |
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struct trace_entry ent; |
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|
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__common_field(unsigned short, type); |
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__common_field(unsigned char, flags); |
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__common_field(unsigned char, preempt_count); |
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__common_field(int, pid); |
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return ret; |
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} |
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static void trace_destroy_fields(struct trace_event_call *call) |
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{ |
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struct ftrace_event_field *field, *next; |
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struct list_head *head; |
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head = trace_get_fields(call); |
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list_for_each_entry_safe(field, next, head, link) { |
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list_del(&field->link); |
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kmem_cache_free(field_cachep, field); |
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} |
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} |
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|
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/* |
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* run-time version of trace_event_get_offsets_<call>() that returns the last |
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* accessible offset of trace fields excluding __dynamic_array bytes |
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*/ |
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int trace_event_get_offsets(struct trace_event_call *call) |
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{ |
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struct ftrace_event_field *tail; |
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struct list_head *head; |
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head = trace_get_fields(call); |
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/* |
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* head->next points to the last field with the largest offset, |
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* since it was added last by trace_define_field() |
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*/ |
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tail = list_first_entry(head, struct ftrace_event_field, link); |
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return tail->offset + tail->size; |
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} |
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|
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/* |
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* Check if the referenced field is an array and return true, |
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* as arrays are OK to dereference. |
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*/ |
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static bool test_field(const char *fmt, struct trace_event_call *call) |
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{ |
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struct trace_event_fields *field = call->class->fields_array; |
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const char *array_descriptor; |
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const char *p = fmt; |
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int len; |
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|
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if (!(len = str_has_prefix(fmt, "REC->"))) |
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return false; |
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fmt += len; |
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for (p = fmt; *p; p++) { |
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if (!isalnum(*p) && *p != '_') |
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break; |
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} |
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len = p - fmt; |
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|
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for (; field->type; field++) { |
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if (strncmp(field->name, fmt, len) || |
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field->name[len]) |
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continue; |
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array_descriptor = strchr(field->type, '['); |
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/* This is an array and is OK to dereference. */ |
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return array_descriptor != NULL; |
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} |
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return false; |
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} |
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|
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/* |
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* Examine the print fmt of the event looking for unsafe dereference |
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* pointers using %p* that could be recorded in the trace event and |
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* much later referenced after the pointer was freed. Dereferencing |
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* pointers are OK, if it is dereferenced into the event itself. |
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*/ |
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static void test_event_printk(struct trace_event_call *call) |
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{ |
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u64 dereference_flags = 0; |
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bool first = true; |
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const char *fmt, *c, *r, *a; |
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int parens = 0; |
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char in_quote = 0; |
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int start_arg = 0; |
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int arg = 0; |
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int i; |
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|
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fmt = call->print_fmt; |
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if (!fmt) |
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return; |
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for (i = 0; fmt[i]; i++) { |
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switch (fmt[i]) { |
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case '\\': |
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i++; |
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if (!fmt[i]) |
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return; |
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continue; |
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case '"': |
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case '\'': |
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/* |
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* The print fmt starts with a string that |
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* is processed first to find %p* usage, |
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* then after the first string, the print fmt |
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* contains arguments that are used to check |
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* if the dereferenced %p* usage is safe. |
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*/ |
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if (first) { |
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if (fmt[i] == '\'') |
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continue; |
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if (in_quote) { |
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arg = 0; |
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first = false; |
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/* |
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* If there was no %p* uses |
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* the fmt is OK. |
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*/ |
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if (!dereference_flags) |
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return; |
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} |
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} |
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if (in_quote) { |
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if (in_quote == fmt[i]) |
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in_quote = 0; |
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} else { |
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in_quote = fmt[i]; |
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} |
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continue; |
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case '%': |
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if (!first || !in_quote) |
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continue; |
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i++; |
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if (!fmt[i]) |
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return; |
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switch (fmt[i]) { |
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case '%': |
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continue; |
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case 'p': |
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/* Find dereferencing fields */ |
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switch (fmt[i + 1]) { |
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case 'B': case 'R': case 'r': |
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case 'b': case 'M': case 'm': |
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case 'I': case 'i': case 'E': |
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case 'U': case 'V': case 'N': |
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case 'a': case 'd': case 'D': |
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case 'g': case 't': case 'C': |
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case 'O': case 'f': |
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if (WARN_ONCE(arg == 63, |
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"Too many args for event: %s", |
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trace_event_name(call))) |
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return; |
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dereference_flags |= 1ULL << arg; |
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} |
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break; |
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default: |
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{ |
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bool star = false; |
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int j; |
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|
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/* Increment arg if %*s exists. */ |
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for (j = 0; fmt[i + j]; j++) { |
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if (isdigit(fmt[i + j]) || |
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fmt[i + j] == '.') |
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continue; |
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if (fmt[i + j] == '*') { |
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star = true; |
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continue; |
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} |
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if ((fmt[i + j] == 's') && star) |
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arg++; |
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break; |
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} |
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break; |
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} /* default */ |
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|
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} /* switch */ |
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arg++; |
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continue; |
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case '(': |
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if (in_quote) |
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continue; |
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parens++; |
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continue; |
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case ')': |
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if (in_quote) |
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continue; |
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parens--; |
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if (WARN_ONCE(parens < 0, |
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"Paren mismatch for event: %s\narg='%s'\n%*s", |
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trace_event_name(call), |
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fmt + start_arg, |
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(i - start_arg) + 5, "^")) |
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return; |
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continue; |
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case ',': |
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if (in_quote || parens) |
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continue; |
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i++; |
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while (isspace(fmt[i])) |
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i++; |
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start_arg = i; |
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if (!(dereference_flags & (1ULL << arg))) |
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goto next_arg; |
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/* Find the REC-> in the argument */ |
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c = strchr(fmt + i, ','); |
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r = strstr(fmt + i, "REC->"); |
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if (r && (!c || r < c)) { |
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/* |
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* Addresses of events on the buffer, |
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* or an array on the buffer is |
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* OK to dereference. |
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* There's ways to fool this, but |
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* this is to catch common mistakes, |
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* not malicious code. |
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*/ |
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a = strchr(fmt + i, '&'); |
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if ((a && (a < r)) || test_field(r, call)) |
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dereference_flags &= ~(1ULL << arg); |
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} |
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next_arg: |
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i--; |
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arg++; |
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} |
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} |
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|
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/* |
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* If you triggered the below warning, the trace event reported |
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* uses an unsafe dereference pointer %p*. As the data stored |
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* at the trace event time may no longer exist when the trace |
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* event is printed, dereferencing to the original source is |
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* unsafe. The source of the dereference must be copied into the |
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* event itself, and the dereference must access the copy instead. |
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*/ |
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if (WARN_ON_ONCE(dereference_flags)) { |
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arg = 1; |
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while (!(dereference_flags & 1)) { |
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dereference_flags >>= 1; |
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arg++; |
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} |
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pr_warn("event %s has unsafe dereference of argument %d\n", |
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trace_event_name(call), arg); |
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pr_warn("print_fmt: %s\n", fmt); |
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} |
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} |
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int trace_event_raw_init(struct trace_event_call *call) |
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{ |
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int id; |
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|
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id = register_trace_event(&call->event); |
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if (!id) |
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return -ENODEV; |
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|
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test_event_printk(call); |
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(trace_event_raw_init); |
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bool trace_event_ignore_this_pid(struct trace_event_file *trace_file) |
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{ |
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struct trace_array *tr = trace_file->tr; |
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struct trace_array_cpu *data; |
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struct trace_pid_list *no_pid_list; |
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struct trace_pid_list *pid_list; |
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pid_list = rcu_dereference_raw(tr->filtered_pids); |
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no_pid_list = rcu_dereference_raw(tr->filtered_no_pids); |
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if (!pid_list && !no_pid_list) |
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return false; |
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data = this_cpu_ptr(tr->array_buffer.data); |
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|
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return data->ignore_pid; |
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} |
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EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid); |
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void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer, |
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struct trace_event_file *trace_file, |
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unsigned long len) |
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{ |
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struct trace_event_call *event_call = trace_file->event_call; |
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|
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if ((trace_file->flags & EVENT_FILE_FL_PID_FILTER) && |
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trace_event_ignore_this_pid(trace_file)) |
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return NULL; |
|
|
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/* |
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* If CONFIG_PREEMPTION is enabled, then the tracepoint itself disables |
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* preemption (adding one to the preempt_count). Since we are |
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* interested in the preempt_count at the time the tracepoint was |
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* hit, we need to subtract one to offset the increment. |
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*/ |
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fbuffer->trace_ctx = tracing_gen_ctx_dec(); |
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fbuffer->trace_file = trace_file; |
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|
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fbuffer->event = |
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trace_event_buffer_lock_reserve(&fbuffer->buffer, trace_file, |
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event_call->event.type, len, |
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fbuffer->trace_ctx); |
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if (!fbuffer->event) |
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return NULL; |
|
|
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fbuffer->regs = NULL; |
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fbuffer->entry = ring_buffer_event_data(fbuffer->event); |
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return fbuffer->entry; |
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} |
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EXPORT_SYMBOL_GPL(trace_event_buffer_reserve); |
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|
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int trace_event_reg(struct trace_event_call *call, |
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enum trace_reg type, void *data) |
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{ |
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struct trace_event_file *file = data; |
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|
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WARN_ON(!(call->flags & TRACE_EVENT_FL_TRACEPOINT)); |
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switch (type) { |
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case TRACE_REG_REGISTER: |
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return tracepoint_probe_register(call->tp, |
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call->class->probe, |
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file); |
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case TRACE_REG_UNREGISTER: |
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tracepoint_probe_unregister(call->tp, |
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call->class->probe, |
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file); |
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return 0; |
|
|
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#ifdef CONFIG_PERF_EVENTS |
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case TRACE_REG_PERF_REGISTER: |
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return tracepoint_probe_register(call->tp, |
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call->class->perf_probe, |
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call); |
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case TRACE_REG_PERF_UNREGISTER: |
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tracepoint_probe_unregister(call->tp, |
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call->class->perf_probe, |
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call); |
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return 0; |
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case TRACE_REG_PERF_OPEN: |
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case TRACE_REG_PERF_CLOSE: |
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case TRACE_REG_PERF_ADD: |
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case TRACE_REG_PERF_DEL: |
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return 0; |
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#endif |
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} |
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return 0; |
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} |
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EXPORT_SYMBOL_GPL(trace_event_reg); |
|
|
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void trace_event_enable_cmd_record(bool enable) |
|
{ |
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struct trace_event_file *file; |
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struct trace_array *tr; |
|
|
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lockdep_assert_held(&event_mutex); |
|
|
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do_for_each_event_file(tr, file) { |
|
|
|
if (!(file->flags & EVENT_FILE_FL_ENABLED)) |
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continue; |
|
|
|
if (enable) { |
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tracing_start_cmdline_record(); |
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set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); |
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} else { |
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tracing_stop_cmdline_record(); |
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clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); |
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} |
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} while_for_each_event_file(); |
|
} |
|
|
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void trace_event_enable_tgid_record(bool enable) |
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{ |
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struct trace_event_file *file; |
|
struct trace_array *tr; |
|
|
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lockdep_assert_held(&event_mutex); |
|
|
|
do_for_each_event_file(tr, file) { |
|
if (!(file->flags & EVENT_FILE_FL_ENABLED)) |
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continue; |
|
|
|
if (enable) { |
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tracing_start_tgid_record(); |
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set_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); |
|
} else { |
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tracing_stop_tgid_record(); |
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clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, |
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&file->flags); |
|
} |
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} while_for_each_event_file(); |
|
} |
|
|
|
static int __ftrace_event_enable_disable(struct trace_event_file *file, |
|
int enable, int soft_disable) |
|
{ |
|
struct trace_event_call *call = file->event_call; |
|
struct trace_array *tr = file->tr; |
|
unsigned long file_flags = file->flags; |
|
int ret = 0; |
|
int disable; |
|
|
|
switch (enable) { |
|
case 0: |
|
/* |
|
* When soft_disable is set and enable is cleared, the sm_ref |
|
* reference counter is decremented. If it reaches 0, we want |
|
* to clear the SOFT_DISABLED flag but leave the event in the |
|
* state that it was. That is, if the event was enabled and |
|
* SOFT_DISABLED isn't set, then do nothing. But if SOFT_DISABLED |
|
* is set we do not want the event to be enabled before we |
|
* clear the bit. |
|
* |
|
* When soft_disable is not set but the SOFT_MODE flag is, |
|
* we do nothing. Do not disable the tracepoint, otherwise |
|
* "soft enable"s (clearing the SOFT_DISABLED bit) wont work. |
|
*/ |
|
if (soft_disable) { |
|
if (atomic_dec_return(&file->sm_ref) > 0) |
|
break; |
|
disable = file->flags & EVENT_FILE_FL_SOFT_DISABLED; |
|
clear_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags); |
|
} else |
|
disable = !(file->flags & EVENT_FILE_FL_SOFT_MODE); |
|
|
|
if (disable && (file->flags & EVENT_FILE_FL_ENABLED)) { |
|
clear_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags); |
|
if (file->flags & EVENT_FILE_FL_RECORDED_CMD) { |
|
tracing_stop_cmdline_record(); |
|
clear_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); |
|
} |
|
|
|
if (file->flags & EVENT_FILE_FL_RECORDED_TGID) { |
|
tracing_stop_tgid_record(); |
|
clear_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); |
|
} |
|
|
|
call->class->reg(call, TRACE_REG_UNREGISTER, file); |
|
} |
|
/* If in SOFT_MODE, just set the SOFT_DISABLE_BIT, else clear it */ |
|
if (file->flags & EVENT_FILE_FL_SOFT_MODE) |
|
set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); |
|
else |
|
clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); |
|
break; |
|
case 1: |
|
/* |
|
* When soft_disable is set and enable is set, we want to |
|
* register the tracepoint for the event, but leave the event |
|
* as is. That means, if the event was already enabled, we do |
|
* nothing (but set SOFT_MODE). If the event is disabled, we |
|
* set SOFT_DISABLED before enabling the event tracepoint, so |
|
* it still seems to be disabled. |
|
*/ |
|
if (!soft_disable) |
|
clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); |
|
else { |
|
if (atomic_inc_return(&file->sm_ref) > 1) |
|
break; |
|
set_bit(EVENT_FILE_FL_SOFT_MODE_BIT, &file->flags); |
|
} |
|
|
|
if (!(file->flags & EVENT_FILE_FL_ENABLED)) { |
|
bool cmd = false, tgid = false; |
|
|
|
/* Keep the event disabled, when going to SOFT_MODE. */ |
|
if (soft_disable) |
|
set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); |
|
|
|
if (tr->trace_flags & TRACE_ITER_RECORD_CMD) { |
|
cmd = true; |
|
tracing_start_cmdline_record(); |
|
set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); |
|
} |
|
|
|
if (tr->trace_flags & TRACE_ITER_RECORD_TGID) { |
|
tgid = true; |
|
tracing_start_tgid_record(); |
|
set_bit(EVENT_FILE_FL_RECORDED_TGID_BIT, &file->flags); |
|
} |
|
|
|
ret = call->class->reg(call, TRACE_REG_REGISTER, file); |
|
if (ret) { |
|
if (cmd) |
|
tracing_stop_cmdline_record(); |
|
if (tgid) |
|
tracing_stop_tgid_record(); |
|
pr_info("event trace: Could not enable event " |
|
"%s\n", trace_event_name(call)); |
|
break; |
|
} |
|
set_bit(EVENT_FILE_FL_ENABLED_BIT, &file->flags); |
|
|
|
/* WAS_ENABLED gets set but never cleared. */ |
|
set_bit(EVENT_FILE_FL_WAS_ENABLED_BIT, &file->flags); |
|
} |
|
break; |
|
} |
|
|
|
/* Enable or disable use of trace_buffered_event */ |
|
if ((file_flags & EVENT_FILE_FL_SOFT_DISABLED) != |
|
(file->flags & EVENT_FILE_FL_SOFT_DISABLED)) { |
|
if (file->flags & EVENT_FILE_FL_SOFT_DISABLED) |
|
trace_buffered_event_enable(); |
|
else |
|
trace_buffered_event_disable(); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
int trace_event_enable_disable(struct trace_event_file *file, |
|
int enable, int soft_disable) |
|
{ |
|
return __ftrace_event_enable_disable(file, enable, soft_disable); |
|
} |
|
|
|
static int ftrace_event_enable_disable(struct trace_event_file *file, |
|
int enable) |
|
{ |
|
return __ftrace_event_enable_disable(file, enable, 0); |
|
} |
|
|
|
static void ftrace_clear_events(struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file; |
|
|
|
mutex_lock(&event_mutex); |
|
list_for_each_entry(file, &tr->events, list) { |
|
ftrace_event_enable_disable(file, 0); |
|
} |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
|
static void |
|
event_filter_pid_sched_process_exit(void *data, struct task_struct *task) |
|
{ |
|
struct trace_pid_list *pid_list; |
|
struct trace_array *tr = data; |
|
|
|
pid_list = rcu_dereference_raw(tr->filtered_pids); |
|
trace_filter_add_remove_task(pid_list, NULL, task); |
|
|
|
pid_list = rcu_dereference_raw(tr->filtered_no_pids); |
|
trace_filter_add_remove_task(pid_list, NULL, task); |
|
} |
|
|
|
static void |
|
event_filter_pid_sched_process_fork(void *data, |
|
struct task_struct *self, |
|
struct task_struct *task) |
|
{ |
|
struct trace_pid_list *pid_list; |
|
struct trace_array *tr = data; |
|
|
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
trace_filter_add_remove_task(pid_list, self, task); |
|
|
|
pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
trace_filter_add_remove_task(pid_list, self, task); |
|
} |
|
|
|
void trace_event_follow_fork(struct trace_array *tr, bool enable) |
|
{ |
|
if (enable) { |
|
register_trace_prio_sched_process_fork(event_filter_pid_sched_process_fork, |
|
tr, INT_MIN); |
|
register_trace_prio_sched_process_free(event_filter_pid_sched_process_exit, |
|
tr, INT_MAX); |
|
} else { |
|
unregister_trace_sched_process_fork(event_filter_pid_sched_process_fork, |
|
tr); |
|
unregister_trace_sched_process_free(event_filter_pid_sched_process_exit, |
|
tr); |
|
} |
|
} |
|
|
|
static void |
|
event_filter_pid_sched_switch_probe_pre(void *data, bool preempt, |
|
struct task_struct *prev, struct task_struct *next) |
|
{ |
|
struct trace_array *tr = data; |
|
struct trace_pid_list *no_pid_list; |
|
struct trace_pid_list *pid_list; |
|
bool ret; |
|
|
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
|
|
/* |
|
* Sched switch is funny, as we only want to ignore it |
|
* in the notrace case if both prev and next should be ignored. |
|
*/ |
|
ret = trace_ignore_this_task(NULL, no_pid_list, prev) && |
|
trace_ignore_this_task(NULL, no_pid_list, next); |
|
|
|
this_cpu_write(tr->array_buffer.data->ignore_pid, ret || |
|
(trace_ignore_this_task(pid_list, NULL, prev) && |
|
trace_ignore_this_task(pid_list, NULL, next))); |
|
} |
|
|
|
static void |
|
event_filter_pid_sched_switch_probe_post(void *data, bool preempt, |
|
struct task_struct *prev, struct task_struct *next) |
|
{ |
|
struct trace_array *tr = data; |
|
struct trace_pid_list *no_pid_list; |
|
struct trace_pid_list *pid_list; |
|
|
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
|
|
this_cpu_write(tr->array_buffer.data->ignore_pid, |
|
trace_ignore_this_task(pid_list, no_pid_list, next)); |
|
} |
|
|
|
static void |
|
event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task) |
|
{ |
|
struct trace_array *tr = data; |
|
struct trace_pid_list *no_pid_list; |
|
struct trace_pid_list *pid_list; |
|
|
|
/* Nothing to do if we are already tracing */ |
|
if (!this_cpu_read(tr->array_buffer.data->ignore_pid)) |
|
return; |
|
|
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
|
|
this_cpu_write(tr->array_buffer.data->ignore_pid, |
|
trace_ignore_this_task(pid_list, no_pid_list, task)); |
|
} |
|
|
|
static void |
|
event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task) |
|
{ |
|
struct trace_array *tr = data; |
|
struct trace_pid_list *no_pid_list; |
|
struct trace_pid_list *pid_list; |
|
|
|
/* Nothing to do if we are not tracing */ |
|
if (this_cpu_read(tr->array_buffer.data->ignore_pid)) |
|
return; |
|
|
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
no_pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
|
|
/* Set tracing if current is enabled */ |
|
this_cpu_write(tr->array_buffer.data->ignore_pid, |
|
trace_ignore_this_task(pid_list, no_pid_list, current)); |
|
} |
|
|
|
static void unregister_pid_events(struct trace_array *tr) |
|
{ |
|
unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr); |
|
unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr); |
|
|
|
unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr); |
|
unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr); |
|
|
|
unregister_trace_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_pre, tr); |
|
unregister_trace_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_post, tr); |
|
|
|
unregister_trace_sched_waking(event_filter_pid_sched_wakeup_probe_pre, tr); |
|
unregister_trace_sched_waking(event_filter_pid_sched_wakeup_probe_post, tr); |
|
} |
|
|
|
static void __ftrace_clear_event_pids(struct trace_array *tr, int type) |
|
{ |
|
struct trace_pid_list *pid_list; |
|
struct trace_pid_list *no_pid_list; |
|
struct trace_event_file *file; |
|
int cpu; |
|
|
|
pid_list = rcu_dereference_protected(tr->filtered_pids, |
|
lockdep_is_held(&event_mutex)); |
|
no_pid_list = rcu_dereference_protected(tr->filtered_no_pids, |
|
lockdep_is_held(&event_mutex)); |
|
|
|
/* Make sure there's something to do */ |
|
if (!pid_type_enabled(type, pid_list, no_pid_list)) |
|
return; |
|
|
|
if (!still_need_pid_events(type, pid_list, no_pid_list)) { |
|
unregister_pid_events(tr); |
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
clear_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags); |
|
} |
|
|
|
for_each_possible_cpu(cpu) |
|
per_cpu_ptr(tr->array_buffer.data, cpu)->ignore_pid = false; |
|
} |
|
|
|
if (type & TRACE_PIDS) |
|
rcu_assign_pointer(tr->filtered_pids, NULL); |
|
|
|
if (type & TRACE_NO_PIDS) |
|
rcu_assign_pointer(tr->filtered_no_pids, NULL); |
|
|
|
/* Wait till all users are no longer using pid filtering */ |
|
tracepoint_synchronize_unregister(); |
|
|
|
if ((type & TRACE_PIDS) && pid_list) |
|
trace_free_pid_list(pid_list); |
|
|
|
if ((type & TRACE_NO_PIDS) && no_pid_list) |
|
trace_free_pid_list(no_pid_list); |
|
} |
|
|
|
static void ftrace_clear_event_pids(struct trace_array *tr, int type) |
|
{ |
|
mutex_lock(&event_mutex); |
|
__ftrace_clear_event_pids(tr, type); |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
|
static void __put_system(struct event_subsystem *system) |
|
{ |
|
struct event_filter *filter = system->filter; |
|
|
|
WARN_ON_ONCE(system_refcount(system) == 0); |
|
if (system_refcount_dec(system)) |
|
return; |
|
|
|
list_del(&system->list); |
|
|
|
if (filter) { |
|
kfree(filter->filter_string); |
|
kfree(filter); |
|
} |
|
kfree_const(system->name); |
|
kfree(system); |
|
} |
|
|
|
static void __get_system(struct event_subsystem *system) |
|
{ |
|
WARN_ON_ONCE(system_refcount(system) == 0); |
|
system_refcount_inc(system); |
|
} |
|
|
|
static void __get_system_dir(struct trace_subsystem_dir *dir) |
|
{ |
|
WARN_ON_ONCE(dir->ref_count == 0); |
|
dir->ref_count++; |
|
__get_system(dir->subsystem); |
|
} |
|
|
|
static void __put_system_dir(struct trace_subsystem_dir *dir) |
|
{ |
|
WARN_ON_ONCE(dir->ref_count == 0); |
|
/* If the subsystem is about to be freed, the dir must be too */ |
|
WARN_ON_ONCE(system_refcount(dir->subsystem) == 1 && dir->ref_count != 1); |
|
|
|
__put_system(dir->subsystem); |
|
if (!--dir->ref_count) |
|
kfree(dir); |
|
} |
|
|
|
static void put_system(struct trace_subsystem_dir *dir) |
|
{ |
|
mutex_lock(&event_mutex); |
|
__put_system_dir(dir); |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
|
static void remove_subsystem(struct trace_subsystem_dir *dir) |
|
{ |
|
if (!dir) |
|
return; |
|
|
|
if (!--dir->nr_events) { |
|
tracefs_remove(dir->entry); |
|
list_del(&dir->list); |
|
__put_system_dir(dir); |
|
} |
|
} |
|
|
|
static void remove_event_file_dir(struct trace_event_file *file) |
|
{ |
|
struct dentry *dir = file->dir; |
|
struct dentry *child; |
|
|
|
if (dir) { |
|
spin_lock(&dir->d_lock); /* probably unneeded */ |
|
list_for_each_entry(child, &dir->d_subdirs, d_child) { |
|
if (d_really_is_positive(child)) /* probably unneeded */ |
|
d_inode(child)->i_private = NULL; |
|
} |
|
spin_unlock(&dir->d_lock); |
|
|
|
tracefs_remove(dir); |
|
} |
|
|
|
list_del(&file->list); |
|
remove_subsystem(file->system); |
|
free_event_filter(file->filter); |
|
kmem_cache_free(file_cachep, file); |
|
} |
|
|
|
/* |
|
* __ftrace_set_clr_event(NULL, NULL, NULL, set) will set/unset all events. |
|
*/ |
|
static int |
|
__ftrace_set_clr_event_nolock(struct trace_array *tr, const char *match, |
|
const char *sub, const char *event, int set) |
|
{ |
|
struct trace_event_file *file; |
|
struct trace_event_call *call; |
|
const char *name; |
|
int ret = -EINVAL; |
|
int eret = 0; |
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
|
|
call = file->event_call; |
|
name = trace_event_name(call); |
|
|
|
if (!name || !call->class || !call->class->reg) |
|
continue; |
|
|
|
if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) |
|
continue; |
|
|
|
if (match && |
|
strcmp(match, name) != 0 && |
|
strcmp(match, call->class->system) != 0) |
|
continue; |
|
|
|
if (sub && strcmp(sub, call->class->system) != 0) |
|
continue; |
|
|
|
if (event && strcmp(event, name) != 0) |
|
continue; |
|
|
|
ret = ftrace_event_enable_disable(file, set); |
|
|
|
/* |
|
* Save the first error and return that. Some events |
|
* may still have been enabled, but let the user |
|
* know that something went wrong. |
|
*/ |
|
if (ret && !eret) |
|
eret = ret; |
|
|
|
ret = eret; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int __ftrace_set_clr_event(struct trace_array *tr, const char *match, |
|
const char *sub, const char *event, int set) |
|
{ |
|
int ret; |
|
|
|
mutex_lock(&event_mutex); |
|
ret = __ftrace_set_clr_event_nolock(tr, match, sub, event, set); |
|
mutex_unlock(&event_mutex); |
|
|
|
return ret; |
|
} |
|
|
|
int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set) |
|
{ |
|
char *event = NULL, *sub = NULL, *match; |
|
int ret; |
|
|
|
if (!tr) |
|
return -ENOENT; |
|
/* |
|
* The buf format can be <subsystem>:<event-name> |
|
* *:<event-name> means any event by that name. |
|
* :<event-name> is the same. |
|
* |
|
* <subsystem>:* means all events in that subsystem |
|
* <subsystem>: means the same. |
|
* |
|
* <name> (no ':') means all events in a subsystem with |
|
* the name <name> or any event that matches <name> |
|
*/ |
|
|
|
match = strsep(&buf, ":"); |
|
if (buf) { |
|
sub = match; |
|
event = buf; |
|
match = NULL; |
|
|
|
if (!strlen(sub) || strcmp(sub, "*") == 0) |
|
sub = NULL; |
|
if (!strlen(event) || strcmp(event, "*") == 0) |
|
event = NULL; |
|
} |
|
|
|
ret = __ftrace_set_clr_event(tr, match, sub, event, set); |
|
|
|
/* Put back the colon to allow this to be called again */ |
|
if (buf) |
|
*(buf - 1) = ':'; |
|
|
|
return ret; |
|
} |
|
|
|
/** |
|
* trace_set_clr_event - enable or disable an event |
|
* @system: system name to match (NULL for any system) |
|
* @event: event name to match (NULL for all events, within system) |
|
* @set: 1 to enable, 0 to disable |
|
* |
|
* This is a way for other parts of the kernel to enable or disable |
|
* event recording. |
|
* |
|
* Returns 0 on success, -EINVAL if the parameters do not match any |
|
* registered events. |
|
*/ |
|
int trace_set_clr_event(const char *system, const char *event, int set) |
|
{ |
|
struct trace_array *tr = top_trace_array(); |
|
|
|
if (!tr) |
|
return -ENODEV; |
|
|
|
return __ftrace_set_clr_event(tr, NULL, system, event, set); |
|
} |
|
EXPORT_SYMBOL_GPL(trace_set_clr_event); |
|
|
|
/** |
|
* trace_array_set_clr_event - enable or disable an event for a trace array. |
|
* @tr: concerned trace array. |
|
* @system: system name to match (NULL for any system) |
|
* @event: event name to match (NULL for all events, within system) |
|
* @enable: true to enable, false to disable |
|
* |
|
* This is a way for other parts of the kernel to enable or disable |
|
* event recording. |
|
* |
|
* Returns 0 on success, -EINVAL if the parameters do not match any |
|
* registered events. |
|
*/ |
|
int trace_array_set_clr_event(struct trace_array *tr, const char *system, |
|
const char *event, bool enable) |
|
{ |
|
int set; |
|
|
|
if (!tr) |
|
return -ENOENT; |
|
|
|
set = (enable == true) ? 1 : 0; |
|
return __ftrace_set_clr_event(tr, NULL, system, event, set); |
|
} |
|
EXPORT_SYMBOL_GPL(trace_array_set_clr_event); |
|
|
|
/* 128 should be much more than enough */ |
|
#define EVENT_BUF_SIZE 127 |
|
|
|
static ssize_t |
|
ftrace_event_write(struct file *file, const char __user *ubuf, |
|
size_t cnt, loff_t *ppos) |
|
{ |
|
struct trace_parser parser; |
|
struct seq_file *m = file->private_data; |
|
struct trace_array *tr = m->private; |
|
ssize_t read, ret; |
|
|
|
if (!cnt) |
|
return 0; |
|
|
|
ret = tracing_update_buffers(); |
|
if (ret < 0) |
|
return ret; |
|
|
|
if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1)) |
|
return -ENOMEM; |
|
|
|
read = trace_get_user(&parser, ubuf, cnt, ppos); |
|
|
|
if (read >= 0 && trace_parser_loaded((&parser))) { |
|
int set = 1; |
|
|
|
if (*parser.buffer == '!') |
|
set = 0; |
|
|
|
ret = ftrace_set_clr_event(tr, parser.buffer + !set, set); |
|
if (ret) |
|
goto out_put; |
|
} |
|
|
|
ret = read; |
|
|
|
out_put: |
|
trace_parser_put(&parser); |
|
|
|
return ret; |
|
} |
|
|
|
static void * |
|
t_next(struct seq_file *m, void *v, loff_t *pos) |
|
{ |
|
struct trace_event_file *file = v; |
|
struct trace_event_call *call; |
|
struct trace_array *tr = m->private; |
|
|
|
(*pos)++; |
|
|
|
list_for_each_entry_continue(file, &tr->events, list) { |
|
call = file->event_call; |
|
/* |
|
* The ftrace subsystem is for showing formats only. |
|
* They can not be enabled or disabled via the event files. |
|
*/ |
|
if (call->class && call->class->reg && |
|
!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) |
|
return file; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
static void *t_start(struct seq_file *m, loff_t *pos) |
|
{ |
|
struct trace_event_file *file; |
|
struct trace_array *tr = m->private; |
|
loff_t l; |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
file = list_entry(&tr->events, struct trace_event_file, list); |
|
for (l = 0; l <= *pos; ) { |
|
file = t_next(m, file, &l); |
|
if (!file) |
|
break; |
|
} |
|
return file; |
|
} |
|
|
|
static void * |
|
s_next(struct seq_file *m, void *v, loff_t *pos) |
|
{ |
|
struct trace_event_file *file = v; |
|
struct trace_array *tr = m->private; |
|
|
|
(*pos)++; |
|
|
|
list_for_each_entry_continue(file, &tr->events, list) { |
|
if (file->flags & EVENT_FILE_FL_ENABLED) |
|
return file; |
|
} |
|
|
|
return NULL; |
|
} |
|
|
|
static void *s_start(struct seq_file *m, loff_t *pos) |
|
{ |
|
struct trace_event_file *file; |
|
struct trace_array *tr = m->private; |
|
loff_t l; |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
file = list_entry(&tr->events, struct trace_event_file, list); |
|
for (l = 0; l <= *pos; ) { |
|
file = s_next(m, file, &l); |
|
if (!file) |
|
break; |
|
} |
|
return file; |
|
} |
|
|
|
static int t_show(struct seq_file *m, void *v) |
|
{ |
|
struct trace_event_file *file = v; |
|
struct trace_event_call *call = file->event_call; |
|
|
|
if (strcmp(call->class->system, TRACE_SYSTEM) != 0) |
|
seq_printf(m, "%s:", call->class->system); |
|
seq_printf(m, "%s\n", trace_event_name(call)); |
|
|
|
return 0; |
|
} |
|
|
|
static void t_stop(struct seq_file *m, void *p) |
|
{ |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
|
static void * |
|
__next(struct seq_file *m, void *v, loff_t *pos, int type) |
|
{ |
|
struct trace_array *tr = m->private; |
|
struct trace_pid_list *pid_list; |
|
|
|
if (type == TRACE_PIDS) |
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
else |
|
pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
|
|
return trace_pid_next(pid_list, v, pos); |
|
} |
|
|
|
static void * |
|
p_next(struct seq_file *m, void *v, loff_t *pos) |
|
{ |
|
return __next(m, v, pos, TRACE_PIDS); |
|
} |
|
|
|
static void * |
|
np_next(struct seq_file *m, void *v, loff_t *pos) |
|
{ |
|
return __next(m, v, pos, TRACE_NO_PIDS); |
|
} |
|
|
|
static void *__start(struct seq_file *m, loff_t *pos, int type) |
|
__acquires(RCU) |
|
{ |
|
struct trace_pid_list *pid_list; |
|
struct trace_array *tr = m->private; |
|
|
|
/* |
|
* Grab the mutex, to keep calls to p_next() having the same |
|
* tr->filtered_pids as p_start() has. |
|
* If we just passed the tr->filtered_pids around, then RCU would |
|
* have been enough, but doing that makes things more complex. |
|
*/ |
|
mutex_lock(&event_mutex); |
|
rcu_read_lock_sched(); |
|
|
|
if (type == TRACE_PIDS) |
|
pid_list = rcu_dereference_sched(tr->filtered_pids); |
|
else |
|
pid_list = rcu_dereference_sched(tr->filtered_no_pids); |
|
|
|
if (!pid_list) |
|
return NULL; |
|
|
|
return trace_pid_start(pid_list, pos); |
|
} |
|
|
|
static void *p_start(struct seq_file *m, loff_t *pos) |
|
__acquires(RCU) |
|
{ |
|
return __start(m, pos, TRACE_PIDS); |
|
} |
|
|
|
static void *np_start(struct seq_file *m, loff_t *pos) |
|
__acquires(RCU) |
|
{ |
|
return __start(m, pos, TRACE_NO_PIDS); |
|
} |
|
|
|
static void p_stop(struct seq_file *m, void *p) |
|
__releases(RCU) |
|
{ |
|
rcu_read_unlock_sched(); |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
|
static ssize_t |
|
event_enable_read(struct file *filp, char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_event_file *file; |
|
unsigned long flags; |
|
char buf[4] = "0"; |
|
|
|
mutex_lock(&event_mutex); |
|
file = event_file_data(filp); |
|
if (likely(file)) |
|
flags = file->flags; |
|
mutex_unlock(&event_mutex); |
|
|
|
if (!file) |
|
return -ENODEV; |
|
|
|
if (flags & EVENT_FILE_FL_ENABLED && |
|
!(flags & EVENT_FILE_FL_SOFT_DISABLED)) |
|
strcpy(buf, "1"); |
|
|
|
if (flags & EVENT_FILE_FL_SOFT_DISABLED || |
|
flags & EVENT_FILE_FL_SOFT_MODE) |
|
strcat(buf, "*"); |
|
|
|
strcat(buf, "\n"); |
|
|
|
return simple_read_from_buffer(ubuf, cnt, ppos, buf, strlen(buf)); |
|
} |
|
|
|
static ssize_t |
|
event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_event_file *file; |
|
unsigned long val; |
|
int ret; |
|
|
|
ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
|
if (ret) |
|
return ret; |
|
|
|
ret = tracing_update_buffers(); |
|
if (ret < 0) |
|
return ret; |
|
|
|
switch (val) { |
|
case 0: |
|
case 1: |
|
ret = -ENODEV; |
|
mutex_lock(&event_mutex); |
|
file = event_file_data(filp); |
|
if (likely(file)) |
|
ret = ftrace_event_enable_disable(file, val); |
|
mutex_unlock(&event_mutex); |
|
break; |
|
|
|
default: |
|
return -EINVAL; |
|
} |
|
|
|
*ppos += cnt; |
|
|
|
return ret ? ret : cnt; |
|
} |
|
|
|
static ssize_t |
|
system_enable_read(struct file *filp, char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
const char set_to_char[4] = { '?', '0', '1', 'X' }; |
|
struct trace_subsystem_dir *dir = filp->private_data; |
|
struct event_subsystem *system = dir->subsystem; |
|
struct trace_event_call *call; |
|
struct trace_event_file *file; |
|
struct trace_array *tr = dir->tr; |
|
char buf[2]; |
|
int set = 0; |
|
int ret; |
|
|
|
mutex_lock(&event_mutex); |
|
list_for_each_entry(file, &tr->events, list) { |
|
call = file->event_call; |
|
if ((call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) || |
|
!trace_event_name(call) || !call->class || !call->class->reg) |
|
continue; |
|
|
|
if (system && strcmp(call->class->system, system->name) != 0) |
|
continue; |
|
|
|
/* |
|
* We need to find out if all the events are set |
|
* or if all events or cleared, or if we have |
|
* a mixture. |
|
*/ |
|
set |= (1 << !!(file->flags & EVENT_FILE_FL_ENABLED)); |
|
|
|
/* |
|
* If we have a mixture, no need to look further. |
|
*/ |
|
if (set == 3) |
|
break; |
|
} |
|
mutex_unlock(&event_mutex); |
|
|
|
buf[0] = set_to_char[set]; |
|
buf[1] = '\n'; |
|
|
|
ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); |
|
|
|
return ret; |
|
} |
|
|
|
static ssize_t |
|
system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_subsystem_dir *dir = filp->private_data; |
|
struct event_subsystem *system = dir->subsystem; |
|
const char *name = NULL; |
|
unsigned long val; |
|
ssize_t ret; |
|
|
|
ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
|
if (ret) |
|
return ret; |
|
|
|
ret = tracing_update_buffers(); |
|
if (ret < 0) |
|
return ret; |
|
|
|
if (val != 0 && val != 1) |
|
return -EINVAL; |
|
|
|
/* |
|
* Opening of "enable" adds a ref count to system, |
|
* so the name is safe to use. |
|
*/ |
|
if (system) |
|
name = system->name; |
|
|
|
ret = __ftrace_set_clr_event(dir->tr, NULL, name, NULL, val); |
|
if (ret) |
|
goto out; |
|
|
|
ret = cnt; |
|
|
|
out: |
|
*ppos += cnt; |
|
|
|
return ret; |
|
} |
|
|
|
enum { |
|
FORMAT_HEADER = 1, |
|
FORMAT_FIELD_SEPERATOR = 2, |
|
FORMAT_PRINTFMT = 3, |
|
}; |
|
|
|
static void *f_next(struct seq_file *m, void *v, loff_t *pos) |
|
{ |
|
struct trace_event_call *call = event_file_data(m->private); |
|
struct list_head *common_head = &ftrace_common_fields; |
|
struct list_head *head = trace_get_fields(call); |
|
struct list_head *node = v; |
|
|
|
(*pos)++; |
|
|
|
switch ((unsigned long)v) { |
|
case FORMAT_HEADER: |
|
node = common_head; |
|
break; |
|
|
|
case FORMAT_FIELD_SEPERATOR: |
|
node = head; |
|
break; |
|
|
|
case FORMAT_PRINTFMT: |
|
/* all done */ |
|
return NULL; |
|
} |
|
|
|
node = node->prev; |
|
if (node == common_head) |
|
return (void *)FORMAT_FIELD_SEPERATOR; |
|
else if (node == head) |
|
return (void *)FORMAT_PRINTFMT; |
|
else |
|
return node; |
|
} |
|
|
|
static int f_show(struct seq_file *m, void *v) |
|
{ |
|
struct trace_event_call *call = event_file_data(m->private); |
|
struct ftrace_event_field *field; |
|
const char *array_descriptor; |
|
|
|
switch ((unsigned long)v) { |
|
case FORMAT_HEADER: |
|
seq_printf(m, "name: %s\n", trace_event_name(call)); |
|
seq_printf(m, "ID: %d\n", call->event.type); |
|
seq_puts(m, "format:\n"); |
|
return 0; |
|
|
|
case FORMAT_FIELD_SEPERATOR: |
|
seq_putc(m, '\n'); |
|
return 0; |
|
|
|
case FORMAT_PRINTFMT: |
|
seq_printf(m, "\nprint fmt: %s\n", |
|
call->print_fmt); |
|
return 0; |
|
} |
|
|
|
field = list_entry(v, struct ftrace_event_field, link); |
|
/* |
|
* Smartly shows the array type(except dynamic array). |
|
* Normal: |
|
* field:TYPE VAR |
|
* If TYPE := TYPE[LEN], it is shown: |
|
* field:TYPE VAR[LEN] |
|
*/ |
|
array_descriptor = strchr(field->type, '['); |
|
|
|
if (str_has_prefix(field->type, "__data_loc")) |
|
array_descriptor = NULL; |
|
|
|
if (!array_descriptor) |
|
seq_printf(m, "\tfield:%s %s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", |
|
field->type, field->name, field->offset, |
|
field->size, !!field->is_signed); |
|
else |
|
seq_printf(m, "\tfield:%.*s %s%s;\toffset:%u;\tsize:%u;\tsigned:%d;\n", |
|
(int)(array_descriptor - field->type), |
|
field->type, field->name, |
|
array_descriptor, field->offset, |
|
field->size, !!field->is_signed); |
|
|
|
return 0; |
|
} |
|
|
|
static void *f_start(struct seq_file *m, loff_t *pos) |
|
{ |
|
void *p = (void *)FORMAT_HEADER; |
|
loff_t l = 0; |
|
|
|
/* ->stop() is called even if ->start() fails */ |
|
mutex_lock(&event_mutex); |
|
if (!event_file_data(m->private)) |
|
return ERR_PTR(-ENODEV); |
|
|
|
while (l < *pos && p) |
|
p = f_next(m, p, &l); |
|
|
|
return p; |
|
} |
|
|
|
static void f_stop(struct seq_file *m, void *p) |
|
{ |
|
mutex_unlock(&event_mutex); |
|
} |
|
|
|
static const struct seq_operations trace_format_seq_ops = { |
|
.start = f_start, |
|
.next = f_next, |
|
.stop = f_stop, |
|
.show = f_show, |
|
}; |
|
|
|
static int trace_format_open(struct inode *inode, struct file *file) |
|
{ |
|
struct seq_file *m; |
|
int ret; |
|
|
|
/* Do we want to hide event format files on tracefs lockdown? */ |
|
|
|
ret = seq_open(file, &trace_format_seq_ops); |
|
if (ret < 0) |
|
return ret; |
|
|
|
m = file->private_data; |
|
m->private = file; |
|
|
|
return 0; |
|
} |
|
|
|
static ssize_t |
|
event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) |
|
{ |
|
int id = (long)event_file_data(filp); |
|
char buf[32]; |
|
int len; |
|
|
|
if (unlikely(!id)) |
|
return -ENODEV; |
|
|
|
len = sprintf(buf, "%d\n", id); |
|
|
|
return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); |
|
} |
|
|
|
static ssize_t |
|
event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_event_file *file; |
|
struct trace_seq *s; |
|
int r = -ENODEV; |
|
|
|
if (*ppos) |
|
return 0; |
|
|
|
s = kmalloc(sizeof(*s), GFP_KERNEL); |
|
|
|
if (!s) |
|
return -ENOMEM; |
|
|
|
trace_seq_init(s); |
|
|
|
mutex_lock(&event_mutex); |
|
file = event_file_data(filp); |
|
if (file) |
|
print_event_filter(file, s); |
|
mutex_unlock(&event_mutex); |
|
|
|
if (file) |
|
r = simple_read_from_buffer(ubuf, cnt, ppos, |
|
s->buffer, trace_seq_used(s)); |
|
|
|
kfree(s); |
|
|
|
return r; |
|
} |
|
|
|
static ssize_t |
|
event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_event_file *file; |
|
char *buf; |
|
int err = -ENODEV; |
|
|
|
if (cnt >= PAGE_SIZE) |
|
return -EINVAL; |
|
|
|
buf = memdup_user_nul(ubuf, cnt); |
|
if (IS_ERR(buf)) |
|
return PTR_ERR(buf); |
|
|
|
mutex_lock(&event_mutex); |
|
file = event_file_data(filp); |
|
if (file) |
|
err = apply_event_filter(file, buf); |
|
mutex_unlock(&event_mutex); |
|
|
|
kfree(buf); |
|
if (err < 0) |
|
return err; |
|
|
|
*ppos += cnt; |
|
|
|
return cnt; |
|
} |
|
|
|
static LIST_HEAD(event_subsystems); |
|
|
|
static int subsystem_open(struct inode *inode, struct file *filp) |
|
{ |
|
struct event_subsystem *system = NULL; |
|
struct trace_subsystem_dir *dir = NULL; /* Initialize for gcc */ |
|
struct trace_array *tr; |
|
int ret; |
|
|
|
if (tracing_is_disabled()) |
|
return -ENODEV; |
|
|
|
/* Make sure the system still exists */ |
|
mutex_lock(&event_mutex); |
|
mutex_lock(&trace_types_lock); |
|
list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
|
list_for_each_entry(dir, &tr->systems, list) { |
|
if (dir == inode->i_private) { |
|
/* Don't open systems with no events */ |
|
if (dir->nr_events) { |
|
__get_system_dir(dir); |
|
system = dir->subsystem; |
|
} |
|
goto exit_loop; |
|
} |
|
} |
|
} |
|
exit_loop: |
|
mutex_unlock(&trace_types_lock); |
|
mutex_unlock(&event_mutex); |
|
|
|
if (!system) |
|
return -ENODEV; |
|
|
|
/* Some versions of gcc think dir can be uninitialized here */ |
|
WARN_ON(!dir); |
|
|
|
/* Still need to increment the ref count of the system */ |
|
if (trace_array_get(tr) < 0) { |
|
put_system(dir); |
|
return -ENODEV; |
|
} |
|
|
|
ret = tracing_open_generic(inode, filp); |
|
if (ret < 0) { |
|
trace_array_put(tr); |
|
put_system(dir); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int system_tr_open(struct inode *inode, struct file *filp) |
|
{ |
|
struct trace_subsystem_dir *dir; |
|
struct trace_array *tr = inode->i_private; |
|
int ret; |
|
|
|
/* Make a temporary dir that has no system but points to tr */ |
|
dir = kzalloc(sizeof(*dir), GFP_KERNEL); |
|
if (!dir) |
|
return -ENOMEM; |
|
|
|
ret = tracing_open_generic_tr(inode, filp); |
|
if (ret < 0) { |
|
kfree(dir); |
|
return ret; |
|
} |
|
dir->tr = tr; |
|
filp->private_data = dir; |
|
|
|
return 0; |
|
} |
|
|
|
static int subsystem_release(struct inode *inode, struct file *file) |
|
{ |
|
struct trace_subsystem_dir *dir = file->private_data; |
|
|
|
trace_array_put(dir->tr); |
|
|
|
/* |
|
* If dir->subsystem is NULL, then this is a temporary |
|
* descriptor that was made for a trace_array to enable |
|
* all subsystems. |
|
*/ |
|
if (dir->subsystem) |
|
put_system(dir); |
|
else |
|
kfree(dir); |
|
|
|
return 0; |
|
} |
|
|
|
static ssize_t |
|
subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_subsystem_dir *dir = filp->private_data; |
|
struct event_subsystem *system = dir->subsystem; |
|
struct trace_seq *s; |
|
int r; |
|
|
|
if (*ppos) |
|
return 0; |
|
|
|
s = kmalloc(sizeof(*s), GFP_KERNEL); |
|
if (!s) |
|
return -ENOMEM; |
|
|
|
trace_seq_init(s); |
|
|
|
print_subsystem_event_filter(system, s); |
|
r = simple_read_from_buffer(ubuf, cnt, ppos, |
|
s->buffer, trace_seq_used(s)); |
|
|
|
kfree(s); |
|
|
|
return r; |
|
} |
|
|
|
static ssize_t |
|
subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, |
|
loff_t *ppos) |
|
{ |
|
struct trace_subsystem_dir *dir = filp->private_data; |
|
char *buf; |
|
int err; |
|
|
|
if (cnt >= PAGE_SIZE) |
|
return -EINVAL; |
|
|
|
buf = memdup_user_nul(ubuf, cnt); |
|
if (IS_ERR(buf)) |
|
return PTR_ERR(buf); |
|
|
|
err = apply_subsystem_event_filter(dir, buf); |
|
kfree(buf); |
|
if (err < 0) |
|
return err; |
|
|
|
*ppos += cnt; |
|
|
|
return cnt; |
|
} |
|
|
|
static ssize_t |
|
show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) |
|
{ |
|
int (*func)(struct trace_seq *s) = filp->private_data; |
|
struct trace_seq *s; |
|
int r; |
|
|
|
if (*ppos) |
|
return 0; |
|
|
|
s = kmalloc(sizeof(*s), GFP_KERNEL); |
|
if (!s) |
|
return -ENOMEM; |
|
|
|
trace_seq_init(s); |
|
|
|
func(s); |
|
r = simple_read_from_buffer(ubuf, cnt, ppos, |
|
s->buffer, trace_seq_used(s)); |
|
|
|
kfree(s); |
|
|
|
return r; |
|
} |
|
|
|
static void ignore_task_cpu(void *data) |
|
{ |
|
struct trace_array *tr = data; |
|
struct trace_pid_list *pid_list; |
|
struct trace_pid_list *no_pid_list; |
|
|
|
/* |
|
* This function is called by on_each_cpu() while the |
|
* event_mutex is held. |
|
*/ |
|
pid_list = rcu_dereference_protected(tr->filtered_pids, |
|
mutex_is_locked(&event_mutex)); |
|
no_pid_list = rcu_dereference_protected(tr->filtered_no_pids, |
|
mutex_is_locked(&event_mutex)); |
|
|
|
this_cpu_write(tr->array_buffer.data->ignore_pid, |
|
trace_ignore_this_task(pid_list, no_pid_list, current)); |
|
} |
|
|
|
static void register_pid_events(struct trace_array *tr) |
|
{ |
|
/* |
|
* Register a probe that is called before all other probes |
|
* to set ignore_pid if next or prev do not match. |
|
* Register a probe this is called after all other probes |
|
* to only keep ignore_pid set if next pid matches. |
|
*/ |
|
register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre, |
|
tr, INT_MAX); |
|
register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post, |
|
tr, 0); |
|
|
|
register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, |
|
tr, INT_MAX); |
|
register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, |
|
tr, 0); |
|
|
|
register_trace_prio_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_pre, |
|
tr, INT_MAX); |
|
register_trace_prio_sched_wakeup_new(event_filter_pid_sched_wakeup_probe_post, |
|
tr, 0); |
|
|
|
register_trace_prio_sched_waking(event_filter_pid_sched_wakeup_probe_pre, |
|
tr, INT_MAX); |
|
register_trace_prio_sched_waking(event_filter_pid_sched_wakeup_probe_post, |
|
tr, 0); |
|
} |
|
|
|
static ssize_t |
|
event_pid_write(struct file *filp, const char __user *ubuf, |
|
size_t cnt, loff_t *ppos, int type) |
|
{ |
|
struct seq_file *m = filp->private_data; |
|
struct trace_array *tr = m->private; |
|
struct trace_pid_list *filtered_pids = NULL; |
|
struct trace_pid_list *other_pids = NULL; |
|
struct trace_pid_list *pid_list; |
|
struct trace_event_file *file; |
|
ssize_t ret; |
|
|
|
if (!cnt) |
|
return 0; |
|
|
|
ret = tracing_update_buffers(); |
|
if (ret < 0) |
|
return ret; |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
if (type == TRACE_PIDS) { |
|
filtered_pids = rcu_dereference_protected(tr->filtered_pids, |
|
lockdep_is_held(&event_mutex)); |
|
other_pids = rcu_dereference_protected(tr->filtered_no_pids, |
|
lockdep_is_held(&event_mutex)); |
|
} else { |
|
filtered_pids = rcu_dereference_protected(tr->filtered_no_pids, |
|
lockdep_is_held(&event_mutex)); |
|
other_pids = rcu_dereference_protected(tr->filtered_pids, |
|
lockdep_is_held(&event_mutex)); |
|
} |
|
|
|
ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt); |
|
if (ret < 0) |
|
goto out; |
|
|
|
if (type == TRACE_PIDS) |
|
rcu_assign_pointer(tr->filtered_pids, pid_list); |
|
else |
|
rcu_assign_pointer(tr->filtered_no_pids, pid_list); |
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
set_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags); |
|
} |
|
|
|
if (filtered_pids) { |
|
tracepoint_synchronize_unregister(); |
|
trace_free_pid_list(filtered_pids); |
|
} else if (pid_list && !other_pids) { |
|
register_pid_events(tr); |
|
} |
|
|
|
/* |
|
* Ignoring of pids is done at task switch. But we have to |
|
* check for those tasks that are currently running. |
|
* Always do this in case a pid was appended or removed. |
|
*/ |
|
on_each_cpu(ignore_task_cpu, tr, 1); |
|
|
|
out: |
|
mutex_unlock(&event_mutex); |
|
|
|
if (ret > 0) |
|
*ppos += ret; |
|
|
|
return ret; |
|
} |
|
|
|
static ssize_t |
|
ftrace_event_pid_write(struct file *filp, const char __user *ubuf, |
|
size_t cnt, loff_t *ppos) |
|
{ |
|
return event_pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS); |
|
} |
|
|
|
static ssize_t |
|
ftrace_event_npid_write(struct file *filp, const char __user *ubuf, |
|
size_t cnt, loff_t *ppos) |
|
{ |
|
return event_pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS); |
|
} |
|
|
|
static int ftrace_event_avail_open(struct inode *inode, struct file *file); |
|
static int ftrace_event_set_open(struct inode *inode, struct file *file); |
|
static int ftrace_event_set_pid_open(struct inode *inode, struct file *file); |
|
static int ftrace_event_set_npid_open(struct inode *inode, struct file *file); |
|
static int ftrace_event_release(struct inode *inode, struct file *file); |
|
|
|
static const struct seq_operations show_event_seq_ops = { |
|
.start = t_start, |
|
.next = t_next, |
|
.show = t_show, |
|
.stop = t_stop, |
|
}; |
|
|
|
static const struct seq_operations show_set_event_seq_ops = { |
|
.start = s_start, |
|
.next = s_next, |
|
.show = t_show, |
|
.stop = t_stop, |
|
}; |
|
|
|
static const struct seq_operations show_set_pid_seq_ops = { |
|
.start = p_start, |
|
.next = p_next, |
|
.show = trace_pid_show, |
|
.stop = p_stop, |
|
}; |
|
|
|
static const struct seq_operations show_set_no_pid_seq_ops = { |
|
.start = np_start, |
|
.next = np_next, |
|
.show = trace_pid_show, |
|
.stop = p_stop, |
|
}; |
|
|
|
static const struct file_operations ftrace_avail_fops = { |
|
.open = ftrace_event_avail_open, |
|
.read = seq_read, |
|
.llseek = seq_lseek, |
|
.release = seq_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_set_event_fops = { |
|
.open = ftrace_event_set_open, |
|
.read = seq_read, |
|
.write = ftrace_event_write, |
|
.llseek = seq_lseek, |
|
.release = ftrace_event_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_set_event_pid_fops = { |
|
.open = ftrace_event_set_pid_open, |
|
.read = seq_read, |
|
.write = ftrace_event_pid_write, |
|
.llseek = seq_lseek, |
|
.release = ftrace_event_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_set_event_notrace_pid_fops = { |
|
.open = ftrace_event_set_npid_open, |
|
.read = seq_read, |
|
.write = ftrace_event_npid_write, |
|
.llseek = seq_lseek, |
|
.release = ftrace_event_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_enable_fops = { |
|
.open = tracing_open_generic, |
|
.read = event_enable_read, |
|
.write = event_enable_write, |
|
.llseek = default_llseek, |
|
}; |
|
|
|
static const struct file_operations ftrace_event_format_fops = { |
|
.open = trace_format_open, |
|
.read = seq_read, |
|
.llseek = seq_lseek, |
|
.release = seq_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_event_id_fops = { |
|
.read = event_id_read, |
|
.llseek = default_llseek, |
|
}; |
|
|
|
static const struct file_operations ftrace_event_filter_fops = { |
|
.open = tracing_open_generic, |
|
.read = event_filter_read, |
|
.write = event_filter_write, |
|
.llseek = default_llseek, |
|
}; |
|
|
|
static const struct file_operations ftrace_subsystem_filter_fops = { |
|
.open = subsystem_open, |
|
.read = subsystem_filter_read, |
|
.write = subsystem_filter_write, |
|
.llseek = default_llseek, |
|
.release = subsystem_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_system_enable_fops = { |
|
.open = subsystem_open, |
|
.read = system_enable_read, |
|
.write = system_enable_write, |
|
.llseek = default_llseek, |
|
.release = subsystem_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_tr_enable_fops = { |
|
.open = system_tr_open, |
|
.read = system_enable_read, |
|
.write = system_enable_write, |
|
.llseek = default_llseek, |
|
.release = subsystem_release, |
|
}; |
|
|
|
static const struct file_operations ftrace_show_header_fops = { |
|
.open = tracing_open_generic, |
|
.read = show_header, |
|
.llseek = default_llseek, |
|
}; |
|
|
|
static int |
|
ftrace_event_open(struct inode *inode, struct file *file, |
|
const struct seq_operations *seq_ops) |
|
{ |
|
struct seq_file *m; |
|
int ret; |
|
|
|
ret = security_locked_down(LOCKDOWN_TRACEFS); |
|
if (ret) |
|
return ret; |
|
|
|
ret = seq_open(file, seq_ops); |
|
if (ret < 0) |
|
return ret; |
|
m = file->private_data; |
|
/* copy tr over to seq ops */ |
|
m->private = inode->i_private; |
|
|
|
return ret; |
|
} |
|
|
|
static int ftrace_event_release(struct inode *inode, struct file *file) |
|
{ |
|
struct trace_array *tr = inode->i_private; |
|
|
|
trace_array_put(tr); |
|
|
|
return seq_release(inode, file); |
|
} |
|
|
|
static int |
|
ftrace_event_avail_open(struct inode *inode, struct file *file) |
|
{ |
|
const struct seq_operations *seq_ops = &show_event_seq_ops; |
|
|
|
/* Checks for tracefs lockdown */ |
|
return ftrace_event_open(inode, file, seq_ops); |
|
} |
|
|
|
static int |
|
ftrace_event_set_open(struct inode *inode, struct file *file) |
|
{ |
|
const struct seq_operations *seq_ops = &show_set_event_seq_ops; |
|
struct trace_array *tr = inode->i_private; |
|
int ret; |
|
|
|
ret = tracing_check_open_get_tr(tr); |
|
if (ret) |
|
return ret; |
|
|
|
if ((file->f_mode & FMODE_WRITE) && |
|
(file->f_flags & O_TRUNC)) |
|
ftrace_clear_events(tr); |
|
|
|
ret = ftrace_event_open(inode, file, seq_ops); |
|
if (ret < 0) |
|
trace_array_put(tr); |
|
return ret; |
|
} |
|
|
|
static int |
|
ftrace_event_set_pid_open(struct inode *inode, struct file *file) |
|
{ |
|
const struct seq_operations *seq_ops = &show_set_pid_seq_ops; |
|
struct trace_array *tr = inode->i_private; |
|
int ret; |
|
|
|
ret = tracing_check_open_get_tr(tr); |
|
if (ret) |
|
return ret; |
|
|
|
if ((file->f_mode & FMODE_WRITE) && |
|
(file->f_flags & O_TRUNC)) |
|
ftrace_clear_event_pids(tr, TRACE_PIDS); |
|
|
|
ret = ftrace_event_open(inode, file, seq_ops); |
|
if (ret < 0) |
|
trace_array_put(tr); |
|
return ret; |
|
} |
|
|
|
static int |
|
ftrace_event_set_npid_open(struct inode *inode, struct file *file) |
|
{ |
|
const struct seq_operations *seq_ops = &show_set_no_pid_seq_ops; |
|
struct trace_array *tr = inode->i_private; |
|
int ret; |
|
|
|
ret = tracing_check_open_get_tr(tr); |
|
if (ret) |
|
return ret; |
|
|
|
if ((file->f_mode & FMODE_WRITE) && |
|
(file->f_flags & O_TRUNC)) |
|
ftrace_clear_event_pids(tr, TRACE_NO_PIDS); |
|
|
|
ret = ftrace_event_open(inode, file, seq_ops); |
|
if (ret < 0) |
|
trace_array_put(tr); |
|
return ret; |
|
} |
|
|
|
static struct event_subsystem * |
|
create_new_subsystem(const char *name) |
|
{ |
|
struct event_subsystem *system; |
|
|
|
/* need to create new entry */ |
|
system = kmalloc(sizeof(*system), GFP_KERNEL); |
|
if (!system) |
|
return NULL; |
|
|
|
system->ref_count = 1; |
|
|
|
/* Only allocate if dynamic (kprobes and modules) */ |
|
system->name = kstrdup_const(name, GFP_KERNEL); |
|
if (!system->name) |
|
goto out_free; |
|
|
|
system->filter = NULL; |
|
|
|
system->filter = kzalloc(sizeof(struct event_filter), GFP_KERNEL); |
|
if (!system->filter) |
|
goto out_free; |
|
|
|
list_add(&system->list, &event_subsystems); |
|
|
|
return system; |
|
|
|
out_free: |
|
kfree_const(system->name); |
|
kfree(system); |
|
return NULL; |
|
} |
|
|
|
static struct dentry * |
|
event_subsystem_dir(struct trace_array *tr, const char *name, |
|
struct trace_event_file *file, struct dentry *parent) |
|
{ |
|
struct trace_subsystem_dir *dir; |
|
struct event_subsystem *system; |
|
struct dentry *entry; |
|
|
|
/* First see if we did not already create this dir */ |
|
list_for_each_entry(dir, &tr->systems, list) { |
|
system = dir->subsystem; |
|
if (strcmp(system->name, name) == 0) { |
|
dir->nr_events++; |
|
file->system = dir; |
|
return dir->entry; |
|
} |
|
} |
|
|
|
/* Now see if the system itself exists. */ |
|
list_for_each_entry(system, &event_subsystems, list) { |
|
if (strcmp(system->name, name) == 0) |
|
break; |
|
} |
|
/* Reset system variable when not found */ |
|
if (&system->list == &event_subsystems) |
|
system = NULL; |
|
|
|
dir = kmalloc(sizeof(*dir), GFP_KERNEL); |
|
if (!dir) |
|
goto out_fail; |
|
|
|
if (!system) { |
|
system = create_new_subsystem(name); |
|
if (!system) |
|
goto out_free; |
|
} else |
|
__get_system(system); |
|
|
|
dir->entry = tracefs_create_dir(name, parent); |
|
if (!dir->entry) { |
|
pr_warn("Failed to create system directory %s\n", name); |
|
__put_system(system); |
|
goto out_free; |
|
} |
|
|
|
dir->tr = tr; |
|
dir->ref_count = 1; |
|
dir->nr_events = 1; |
|
dir->subsystem = system; |
|
file->system = dir; |
|
|
|
/* the ftrace system is special, do not create enable or filter files */ |
|
if (strcmp(name, "ftrace") != 0) { |
|
|
|
entry = tracefs_create_file("filter", 0644, dir->entry, dir, |
|
&ftrace_subsystem_filter_fops); |
|
if (!entry) { |
|
kfree(system->filter); |
|
system->filter = NULL; |
|
pr_warn("Could not create tracefs '%s/filter' entry\n", name); |
|
} |
|
|
|
trace_create_file("enable", 0644, dir->entry, dir, |
|
&ftrace_system_enable_fops); |
|
} |
|
|
|
list_add(&dir->list, &tr->systems); |
|
|
|
return dir->entry; |
|
|
|
out_free: |
|
kfree(dir); |
|
out_fail: |
|
/* Only print this message if failed on memory allocation */ |
|
if (!dir || !system) |
|
pr_warn("No memory to create event subsystem %s\n", name); |
|
return NULL; |
|
} |
|
|
|
static int |
|
event_define_fields(struct trace_event_call *call) |
|
{ |
|
struct list_head *head; |
|
int ret = 0; |
|
|
|
/* |
|
* Other events may have the same class. Only update |
|
* the fields if they are not already defined. |
|
*/ |
|
head = trace_get_fields(call); |
|
if (list_empty(head)) { |
|
struct trace_event_fields *field = call->class->fields_array; |
|
unsigned int offset = sizeof(struct trace_entry); |
|
|
|
for (; field->type; field++) { |
|
if (field->type == TRACE_FUNCTION_TYPE) { |
|
field->define_fields(call); |
|
break; |
|
} |
|
|
|
offset = ALIGN(offset, field->align); |
|
ret = trace_define_field(call, field->type, field->name, |
|
offset, field->size, |
|
field->is_signed, field->filter_type); |
|
if (WARN_ON_ONCE(ret)) { |
|
pr_err("error code is %d\n", ret); |
|
break; |
|
} |
|
|
|
offset += field->size; |
|
} |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int |
|
event_create_dir(struct dentry *parent, struct trace_event_file *file) |
|
{ |
|
struct trace_event_call *call = file->event_call; |
|
struct trace_array *tr = file->tr; |
|
struct dentry *d_events; |
|
const char *name; |
|
int ret; |
|
|
|
/* |
|
* If the trace point header did not define TRACE_SYSTEM |
|
* then the system would be called "TRACE_SYSTEM". |
|
*/ |
|
if (strcmp(call->class->system, TRACE_SYSTEM) != 0) { |
|
d_events = event_subsystem_dir(tr, call->class->system, file, parent); |
|
if (!d_events) |
|
return -ENOMEM; |
|
} else |
|
d_events = parent; |
|
|
|
name = trace_event_name(call); |
|
file->dir = tracefs_create_dir(name, d_events); |
|
if (!file->dir) { |
|
pr_warn("Could not create tracefs '%s' directory\n", name); |
|
return -1; |
|
} |
|
|
|
if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) |
|
trace_create_file("enable", 0644, file->dir, file, |
|
&ftrace_enable_fops); |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
if (call->event.type && call->class->reg) |
|
trace_create_file("id", 0444, file->dir, |
|
(void *)(long)call->event.type, |
|
&ftrace_event_id_fops); |
|
#endif |
|
|
|
ret = event_define_fields(call); |
|
if (ret < 0) { |
|
pr_warn("Could not initialize trace point events/%s\n", name); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Only event directories that can be enabled should have |
|
* triggers or filters. |
|
*/ |
|
if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) { |
|
trace_create_file("filter", 0644, file->dir, file, |
|
&ftrace_event_filter_fops); |
|
|
|
trace_create_file("trigger", 0644, file->dir, file, |
|
&event_trigger_fops); |
|
} |
|
|
|
#ifdef CONFIG_HIST_TRIGGERS |
|
trace_create_file("hist", 0444, file->dir, file, |
|
&event_hist_fops); |
|
#endif |
|
#ifdef CONFIG_HIST_TRIGGERS_DEBUG |
|
trace_create_file("hist_debug", 0444, file->dir, file, |
|
&event_hist_debug_fops); |
|
#endif |
|
trace_create_file("format", 0444, file->dir, call, |
|
&ftrace_event_format_fops); |
|
|
|
#ifdef CONFIG_TRACE_EVENT_INJECT |
|
if (call->event.type && call->class->reg) |
|
trace_create_file("inject", 0200, file->dir, file, |
|
&event_inject_fops); |
|
#endif |
|
|
|
return 0; |
|
} |
|
|
|
static void remove_event_from_tracers(struct trace_event_call *call) |
|
{ |
|
struct trace_event_file *file; |
|
struct trace_array *tr; |
|
|
|
do_for_each_event_file_safe(tr, file) { |
|
if (file->event_call != call) |
|
continue; |
|
|
|
remove_event_file_dir(file); |
|
/* |
|
* The do_for_each_event_file_safe() is |
|
* a double loop. After finding the call for this |
|
* trace_array, we use break to jump to the next |
|
* trace_array. |
|
*/ |
|
break; |
|
} while_for_each_event_file(); |
|
} |
|
|
|
static void event_remove(struct trace_event_call *call) |
|
{ |
|
struct trace_array *tr; |
|
struct trace_event_file *file; |
|
|
|
do_for_each_event_file(tr, file) { |
|
if (file->event_call != call) |
|
continue; |
|
|
|
if (file->flags & EVENT_FILE_FL_WAS_ENABLED) |
|
tr->clear_trace = true; |
|
|
|
ftrace_event_enable_disable(file, 0); |
|
/* |
|
* The do_for_each_event_file() is |
|
* a double loop. After finding the call for this |
|
* trace_array, we use break to jump to the next |
|
* trace_array. |
|
*/ |
|
break; |
|
} while_for_each_event_file(); |
|
|
|
if (call->event.funcs) |
|
__unregister_trace_event(&call->event); |
|
remove_event_from_tracers(call); |
|
list_del(&call->list); |
|
} |
|
|
|
static int event_init(struct trace_event_call *call) |
|
{ |
|
int ret = 0; |
|
const char *name; |
|
|
|
name = trace_event_name(call); |
|
if (WARN_ON(!name)) |
|
return -EINVAL; |
|
|
|
if (call->class->raw_init) { |
|
ret = call->class->raw_init(call); |
|
if (ret < 0 && ret != -ENOSYS) |
|
pr_warn("Could not initialize trace events/%s\n", name); |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static int |
|
__register_event(struct trace_event_call *call, struct module *mod) |
|
{ |
|
int ret; |
|
|
|
ret = event_init(call); |
|
if (ret < 0) |
|
return ret; |
|
|
|
list_add(&call->list, &ftrace_events); |
|
call->mod = mod; |
|
|
|
return 0; |
|
} |
|
|
|
static char *eval_replace(char *ptr, struct trace_eval_map *map, int len) |
|
{ |
|
int rlen; |
|
int elen; |
|
|
|
/* Find the length of the eval value as a string */ |
|
elen = snprintf(ptr, 0, "%ld", map->eval_value); |
|
/* Make sure there's enough room to replace the string with the value */ |
|
if (len < elen) |
|
return NULL; |
|
|
|
snprintf(ptr, elen + 1, "%ld", map->eval_value); |
|
|
|
/* Get the rest of the string of ptr */ |
|
rlen = strlen(ptr + len); |
|
memmove(ptr + elen, ptr + len, rlen); |
|
/* Make sure we end the new string */ |
|
ptr[elen + rlen] = 0; |
|
|
|
return ptr + elen; |
|
} |
|
|
|
static void update_event_printk(struct trace_event_call *call, |
|
struct trace_eval_map *map) |
|
{ |
|
char *ptr; |
|
int quote = 0; |
|
int len = strlen(map->eval_string); |
|
|
|
for (ptr = call->print_fmt; *ptr; ptr++) { |
|
if (*ptr == '\\') { |
|
ptr++; |
|
/* paranoid */ |
|
if (!*ptr) |
|
break; |
|
continue; |
|
} |
|
if (*ptr == '"') { |
|
quote ^= 1; |
|
continue; |
|
} |
|
if (quote) |
|
continue; |
|
if (isdigit(*ptr)) { |
|
/* skip numbers */ |
|
do { |
|
ptr++; |
|
/* Check for alpha chars like ULL */ |
|
} while (isalnum(*ptr)); |
|
if (!*ptr) |
|
break; |
|
/* |
|
* A number must have some kind of delimiter after |
|
* it, and we can ignore that too. |
|
*/ |
|
continue; |
|
} |
|
if (isalpha(*ptr) || *ptr == '_') { |
|
if (strncmp(map->eval_string, ptr, len) == 0 && |
|
!isalnum(ptr[len]) && ptr[len] != '_') { |
|
ptr = eval_replace(ptr, map, len); |
|
/* enum/sizeof string smaller than value */ |
|
if (WARN_ON_ONCE(!ptr)) |
|
return; |
|
/* |
|
* No need to decrement here, as eval_replace() |
|
* returns the pointer to the character passed |
|
* the eval, and two evals can not be placed |
|
* back to back without something in between. |
|
* We can skip that something in between. |
|
*/ |
|
continue; |
|
} |
|
skip_more: |
|
do { |
|
ptr++; |
|
} while (isalnum(*ptr) || *ptr == '_'); |
|
if (!*ptr) |
|
break; |
|
/* |
|
* If what comes after this variable is a '.' or |
|
* '->' then we can continue to ignore that string. |
|
*/ |
|
if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) { |
|
ptr += *ptr == '.' ? 1 : 2; |
|
if (!*ptr) |
|
break; |
|
goto skip_more; |
|
} |
|
/* |
|
* Once again, we can skip the delimiter that came |
|
* after the string. |
|
*/ |
|
continue; |
|
} |
|
} |
|
} |
|
|
|
void trace_event_eval_update(struct trace_eval_map **map, int len) |
|
{ |
|
struct trace_event_call *call, *p; |
|
const char *last_system = NULL; |
|
bool first = false; |
|
int last_i; |
|
int i; |
|
|
|
down_write(&trace_event_sem); |
|
list_for_each_entry_safe(call, p, &ftrace_events, list) { |
|
/* events are usually grouped together with systems */ |
|
if (!last_system || call->class->system != last_system) { |
|
first = true; |
|
last_i = 0; |
|
last_system = call->class->system; |
|
} |
|
|
|
/* |
|
* Since calls are grouped by systems, the likelihood that the |
|
* next call in the iteration belongs to the same system as the |
|
* previous call is high. As an optimization, we skip searching |
|
* for a map[] that matches the call's system if the last call |
|
* was from the same system. That's what last_i is for. If the |
|
* call has the same system as the previous call, then last_i |
|
* will be the index of the first map[] that has a matching |
|
* system. |
|
*/ |
|
for (i = last_i; i < len; i++) { |
|
if (call->class->system == map[i]->system) { |
|
/* Save the first system if need be */ |
|
if (first) { |
|
last_i = i; |
|
first = false; |
|
} |
|
update_event_printk(call, map[i]); |
|
} |
|
} |
|
} |
|
up_write(&trace_event_sem); |
|
} |
|
|
|
static struct trace_event_file * |
|
trace_create_new_event(struct trace_event_call *call, |
|
struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file; |
|
|
|
file = kmem_cache_alloc(file_cachep, GFP_TRACE); |
|
if (!file) |
|
return NULL; |
|
|
|
file->event_call = call; |
|
file->tr = tr; |
|
atomic_set(&file->sm_ref, 0); |
|
atomic_set(&file->tm_ref, 0); |
|
INIT_LIST_HEAD(&file->triggers); |
|
list_add(&file->list, &tr->events); |
|
|
|
return file; |
|
} |
|
|
|
/* Add an event to a trace directory */ |
|
static int |
|
__trace_add_new_event(struct trace_event_call *call, struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file; |
|
|
|
file = trace_create_new_event(call, tr); |
|
if (!file) |
|
return -ENOMEM; |
|
|
|
if (eventdir_initialized) |
|
return event_create_dir(tr->event_dir, file); |
|
else |
|
return event_define_fields(call); |
|
} |
|
|
|
/* |
|
* Just create a descriptor for early init. A descriptor is required |
|
* for enabling events at boot. We want to enable events before |
|
* the filesystem is initialized. |
|
*/ |
|
static int |
|
__trace_early_add_new_event(struct trace_event_call *call, |
|
struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file; |
|
|
|
file = trace_create_new_event(call, tr); |
|
if (!file) |
|
return -ENOMEM; |
|
|
|
return event_define_fields(call); |
|
} |
|
|
|
struct ftrace_module_file_ops; |
|
static void __add_event_to_tracers(struct trace_event_call *call); |
|
|
|
/* Add an additional event_call dynamically */ |
|
int trace_add_event_call(struct trace_event_call *call) |
|
{ |
|
int ret; |
|
lockdep_assert_held(&event_mutex); |
|
|
|
mutex_lock(&trace_types_lock); |
|
|
|
ret = __register_event(call, NULL); |
|
if (ret >= 0) |
|
__add_event_to_tracers(call); |
|
|
|
mutex_unlock(&trace_types_lock); |
|
return ret; |
|
} |
|
|
|
/* |
|
* Must be called under locking of trace_types_lock, event_mutex and |
|
* trace_event_sem. |
|
*/ |
|
static void __trace_remove_event_call(struct trace_event_call *call) |
|
{ |
|
event_remove(call); |
|
trace_destroy_fields(call); |
|
free_event_filter(call->filter); |
|
call->filter = NULL; |
|
} |
|
|
|
static int probe_remove_event_call(struct trace_event_call *call) |
|
{ |
|
struct trace_array *tr; |
|
struct trace_event_file *file; |
|
|
|
#ifdef CONFIG_PERF_EVENTS |
|
if (call->perf_refcount) |
|
return -EBUSY; |
|
#endif |
|
do_for_each_event_file(tr, file) { |
|
if (file->event_call != call) |
|
continue; |
|
/* |
|
* We can't rely on ftrace_event_enable_disable(enable => 0) |
|
* we are going to do, EVENT_FILE_FL_SOFT_MODE can suppress |
|
* TRACE_REG_UNREGISTER. |
|
*/ |
|
if (file->flags & EVENT_FILE_FL_ENABLED) |
|
return -EBUSY; |
|
/* |
|
* The do_for_each_event_file_safe() is |
|
* a double loop. After finding the call for this |
|
* trace_array, we use break to jump to the next |
|
* trace_array. |
|
*/ |
|
break; |
|
} while_for_each_event_file(); |
|
|
|
__trace_remove_event_call(call); |
|
|
|
return 0; |
|
} |
|
|
|
/* Remove an event_call */ |
|
int trace_remove_event_call(struct trace_event_call *call) |
|
{ |
|
int ret; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
mutex_lock(&trace_types_lock); |
|
down_write(&trace_event_sem); |
|
ret = probe_remove_event_call(call); |
|
up_write(&trace_event_sem); |
|
mutex_unlock(&trace_types_lock); |
|
|
|
return ret; |
|
} |
|
|
|
#define for_each_event(event, start, end) \ |
|
for (event = start; \ |
|
(unsigned long)event < (unsigned long)end; \ |
|
event++) |
|
|
|
#ifdef CONFIG_MODULES |
|
|
|
static void trace_module_add_events(struct module *mod) |
|
{ |
|
struct trace_event_call **call, **start, **end; |
|
|
|
if (!mod->num_trace_events) |
|
return; |
|
|
|
/* Don't add infrastructure for mods without tracepoints */ |
|
if (trace_module_has_bad_taint(mod)) { |
|
pr_err("%s: module has bad taint, not creating trace events\n", |
|
mod->name); |
|
return; |
|
} |
|
|
|
start = mod->trace_events; |
|
end = mod->trace_events + mod->num_trace_events; |
|
|
|
for_each_event(call, start, end) { |
|
__register_event(*call, mod); |
|
__add_event_to_tracers(*call); |
|
} |
|
} |
|
|
|
static void trace_module_remove_events(struct module *mod) |
|
{ |
|
struct trace_event_call *call, *p; |
|
|
|
down_write(&trace_event_sem); |
|
list_for_each_entry_safe(call, p, &ftrace_events, list) { |
|
if (call->mod == mod) |
|
__trace_remove_event_call(call); |
|
} |
|
up_write(&trace_event_sem); |
|
|
|
/* |
|
* It is safest to reset the ring buffer if the module being unloaded |
|
* registered any events that were used. The only worry is if |
|
* a new module gets loaded, and takes on the same id as the events |
|
* of this module. When printing out the buffer, traced events left |
|
* over from this module may be passed to the new module events and |
|
* unexpected results may occur. |
|
*/ |
|
tracing_reset_all_online_cpus(); |
|
} |
|
|
|
static int trace_module_notify(struct notifier_block *self, |
|
unsigned long val, void *data) |
|
{ |
|
struct module *mod = data; |
|
|
|
mutex_lock(&event_mutex); |
|
mutex_lock(&trace_types_lock); |
|
switch (val) { |
|
case MODULE_STATE_COMING: |
|
trace_module_add_events(mod); |
|
break; |
|
case MODULE_STATE_GOING: |
|
trace_module_remove_events(mod); |
|
break; |
|
} |
|
mutex_unlock(&trace_types_lock); |
|
mutex_unlock(&event_mutex); |
|
|
|
return NOTIFY_OK; |
|
} |
|
|
|
static struct notifier_block trace_module_nb = { |
|
.notifier_call = trace_module_notify, |
|
.priority = 1, /* higher than trace.c module notify */ |
|
}; |
|
#endif /* CONFIG_MODULES */ |
|
|
|
/* Create a new event directory structure for a trace directory. */ |
|
static void |
|
__trace_add_event_dirs(struct trace_array *tr) |
|
{ |
|
struct trace_event_call *call; |
|
int ret; |
|
|
|
list_for_each_entry(call, &ftrace_events, list) { |
|
ret = __trace_add_new_event(call, tr); |
|
if (ret < 0) |
|
pr_warn("Could not create directory for event %s\n", |
|
trace_event_name(call)); |
|
} |
|
} |
|
|
|
/* Returns any file that matches the system and event */ |
|
struct trace_event_file * |
|
__find_event_file(struct trace_array *tr, const char *system, const char *event) |
|
{ |
|
struct trace_event_file *file; |
|
struct trace_event_call *call; |
|
const char *name; |
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
|
|
call = file->event_call; |
|
name = trace_event_name(call); |
|
|
|
if (!name || !call->class) |
|
continue; |
|
|
|
if (strcmp(event, name) == 0 && |
|
strcmp(system, call->class->system) == 0) |
|
return file; |
|
} |
|
return NULL; |
|
} |
|
|
|
/* Returns valid trace event files that match system and event */ |
|
struct trace_event_file * |
|
find_event_file(struct trace_array *tr, const char *system, const char *event) |
|
{ |
|
struct trace_event_file *file; |
|
|
|
file = __find_event_file(tr, system, event); |
|
if (!file || !file->event_call->class->reg || |
|
file->event_call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) |
|
return NULL; |
|
|
|
return file; |
|
} |
|
|
|
/** |
|
* trace_get_event_file - Find and return a trace event file |
|
* @instance: The name of the trace instance containing the event |
|
* @system: The name of the system containing the event |
|
* @event: The name of the event |
|
* |
|
* Return a trace event file given the trace instance name, trace |
|
* system, and trace event name. If the instance name is NULL, it |
|
* refers to the top-level trace array. |
|
* |
|
* This function will look it up and return it if found, after calling |
|
* trace_array_get() to prevent the instance from going away, and |
|
* increment the event's module refcount to prevent it from being |
|
* removed. |
|
* |
|
* To release the file, call trace_put_event_file(), which will call |
|
* trace_array_put() and decrement the event's module refcount. |
|
* |
|
* Return: The trace event on success, ERR_PTR otherwise. |
|
*/ |
|
struct trace_event_file *trace_get_event_file(const char *instance, |
|
const char *system, |
|
const char *event) |
|
{ |
|
struct trace_array *tr = top_trace_array(); |
|
struct trace_event_file *file = NULL; |
|
int ret = -EINVAL; |
|
|
|
if (instance) { |
|
tr = trace_array_find_get(instance); |
|
if (!tr) |
|
return ERR_PTR(-ENOENT); |
|
} else { |
|
ret = trace_array_get(tr); |
|
if (ret) |
|
return ERR_PTR(ret); |
|
} |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
file = find_event_file(tr, system, event); |
|
if (!file) { |
|
trace_array_put(tr); |
|
ret = -EINVAL; |
|
goto out; |
|
} |
|
|
|
/* Don't let event modules unload while in use */ |
|
ret = try_module_get(file->event_call->mod); |
|
if (!ret) { |
|
trace_array_put(tr); |
|
ret = -EBUSY; |
|
goto out; |
|
} |
|
|
|
ret = 0; |
|
out: |
|
mutex_unlock(&event_mutex); |
|
|
|
if (ret) |
|
file = ERR_PTR(ret); |
|
|
|
return file; |
|
} |
|
EXPORT_SYMBOL_GPL(trace_get_event_file); |
|
|
|
/** |
|
* trace_put_event_file - Release a file from trace_get_event_file() |
|
* @file: The trace event file |
|
* |
|
* If a file was retrieved using trace_get_event_file(), this should |
|
* be called when it's no longer needed. It will cancel the previous |
|
* trace_array_get() called by that function, and decrement the |
|
* event's module refcount. |
|
*/ |
|
void trace_put_event_file(struct trace_event_file *file) |
|
{ |
|
mutex_lock(&event_mutex); |
|
module_put(file->event_call->mod); |
|
mutex_unlock(&event_mutex); |
|
|
|
trace_array_put(file->tr); |
|
} |
|
EXPORT_SYMBOL_GPL(trace_put_event_file); |
|
|
|
#ifdef CONFIG_DYNAMIC_FTRACE |
|
|
|
/* Avoid typos */ |
|
#define ENABLE_EVENT_STR "enable_event" |
|
#define DISABLE_EVENT_STR "disable_event" |
|
|
|
struct event_probe_data { |
|
struct trace_event_file *file; |
|
unsigned long count; |
|
int ref; |
|
bool enable; |
|
}; |
|
|
|
static void update_event_probe(struct event_probe_data *data) |
|
{ |
|
if (data->enable) |
|
clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags); |
|
else |
|
set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &data->file->flags); |
|
} |
|
|
|
static void |
|
event_enable_probe(unsigned long ip, unsigned long parent_ip, |
|
struct trace_array *tr, struct ftrace_probe_ops *ops, |
|
void *data) |
|
{ |
|
struct ftrace_func_mapper *mapper = data; |
|
struct event_probe_data *edata; |
|
void **pdata; |
|
|
|
pdata = ftrace_func_mapper_find_ip(mapper, ip); |
|
if (!pdata || !*pdata) |
|
return; |
|
|
|
edata = *pdata; |
|
update_event_probe(edata); |
|
} |
|
|
|
static void |
|
event_enable_count_probe(unsigned long ip, unsigned long parent_ip, |
|
struct trace_array *tr, struct ftrace_probe_ops *ops, |
|
void *data) |
|
{ |
|
struct ftrace_func_mapper *mapper = data; |
|
struct event_probe_data *edata; |
|
void **pdata; |
|
|
|
pdata = ftrace_func_mapper_find_ip(mapper, ip); |
|
if (!pdata || !*pdata) |
|
return; |
|
|
|
edata = *pdata; |
|
|
|
if (!edata->count) |
|
return; |
|
|
|
/* Skip if the event is in a state we want to switch to */ |
|
if (edata->enable == !(edata->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
|
return; |
|
|
|
if (edata->count != -1) |
|
(edata->count)--; |
|
|
|
update_event_probe(edata); |
|
} |
|
|
|
static int |
|
event_enable_print(struct seq_file *m, unsigned long ip, |
|
struct ftrace_probe_ops *ops, void *data) |
|
{ |
|
struct ftrace_func_mapper *mapper = data; |
|
struct event_probe_data *edata; |
|
void **pdata; |
|
|
|
pdata = ftrace_func_mapper_find_ip(mapper, ip); |
|
|
|
if (WARN_ON_ONCE(!pdata || !*pdata)) |
|
return 0; |
|
|
|
edata = *pdata; |
|
|
|
seq_printf(m, "%ps:", (void *)ip); |
|
|
|
seq_printf(m, "%s:%s:%s", |
|
edata->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, |
|
edata->file->event_call->class->system, |
|
trace_event_name(edata->file->event_call)); |
|
|
|
if (edata->count == -1) |
|
seq_puts(m, ":unlimited\n"); |
|
else |
|
seq_printf(m, ":count=%ld\n", edata->count); |
|
|
|
return 0; |
|
} |
|
|
|
static int |
|
event_enable_init(struct ftrace_probe_ops *ops, struct trace_array *tr, |
|
unsigned long ip, void *init_data, void **data) |
|
{ |
|
struct ftrace_func_mapper *mapper = *data; |
|
struct event_probe_data *edata = init_data; |
|
int ret; |
|
|
|
if (!mapper) { |
|
mapper = allocate_ftrace_func_mapper(); |
|
if (!mapper) |
|
return -ENODEV; |
|
*data = mapper; |
|
} |
|
|
|
ret = ftrace_func_mapper_add_ip(mapper, ip, edata); |
|
if (ret < 0) |
|
return ret; |
|
|
|
edata->ref++; |
|
|
|
return 0; |
|
} |
|
|
|
static int free_probe_data(void *data) |
|
{ |
|
struct event_probe_data *edata = data; |
|
|
|
edata->ref--; |
|
if (!edata->ref) { |
|
/* Remove the SOFT_MODE flag */ |
|
__ftrace_event_enable_disable(edata->file, 0, 1); |
|
module_put(edata->file->event_call->mod); |
|
kfree(edata); |
|
} |
|
return 0; |
|
} |
|
|
|
static void |
|
event_enable_free(struct ftrace_probe_ops *ops, struct trace_array *tr, |
|
unsigned long ip, void *data) |
|
{ |
|
struct ftrace_func_mapper *mapper = data; |
|
struct event_probe_data *edata; |
|
|
|
if (!ip) { |
|
if (!mapper) |
|
return; |
|
free_ftrace_func_mapper(mapper, free_probe_data); |
|
return; |
|
} |
|
|
|
edata = ftrace_func_mapper_remove_ip(mapper, ip); |
|
|
|
if (WARN_ON_ONCE(!edata)) |
|
return; |
|
|
|
if (WARN_ON_ONCE(edata->ref <= 0)) |
|
return; |
|
|
|
free_probe_data(edata); |
|
} |
|
|
|
static struct ftrace_probe_ops event_enable_probe_ops = { |
|
.func = event_enable_probe, |
|
.print = event_enable_print, |
|
.init = event_enable_init, |
|
.free = event_enable_free, |
|
}; |
|
|
|
static struct ftrace_probe_ops event_enable_count_probe_ops = { |
|
.func = event_enable_count_probe, |
|
.print = event_enable_print, |
|
.init = event_enable_init, |
|
.free = event_enable_free, |
|
}; |
|
|
|
static struct ftrace_probe_ops event_disable_probe_ops = { |
|
.func = event_enable_probe, |
|
.print = event_enable_print, |
|
.init = event_enable_init, |
|
.free = event_enable_free, |
|
}; |
|
|
|
static struct ftrace_probe_ops event_disable_count_probe_ops = { |
|
.func = event_enable_count_probe, |
|
.print = event_enable_print, |
|
.init = event_enable_init, |
|
.free = event_enable_free, |
|
}; |
|
|
|
static int |
|
event_enable_func(struct trace_array *tr, struct ftrace_hash *hash, |
|
char *glob, char *cmd, char *param, int enabled) |
|
{ |
|
struct trace_event_file *file; |
|
struct ftrace_probe_ops *ops; |
|
struct event_probe_data *data; |
|
const char *system; |
|
const char *event; |
|
char *number; |
|
bool enable; |
|
int ret; |
|
|
|
if (!tr) |
|
return -ENODEV; |
|
|
|
/* hash funcs only work with set_ftrace_filter */ |
|
if (!enabled || !param) |
|
return -EINVAL; |
|
|
|
system = strsep(¶m, ":"); |
|
if (!param) |
|
return -EINVAL; |
|
|
|
event = strsep(¶m, ":"); |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
ret = -EINVAL; |
|
file = find_event_file(tr, system, event); |
|
if (!file) |
|
goto out; |
|
|
|
enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
|
|
|
if (enable) |
|
ops = param ? &event_enable_count_probe_ops : &event_enable_probe_ops; |
|
else |
|
ops = param ? &event_disable_count_probe_ops : &event_disable_probe_ops; |
|
|
|
if (glob[0] == '!') { |
|
ret = unregister_ftrace_function_probe_func(glob+1, tr, ops); |
|
goto out; |
|
} |
|
|
|
ret = -ENOMEM; |
|
|
|
data = kzalloc(sizeof(*data), GFP_KERNEL); |
|
if (!data) |
|
goto out; |
|
|
|
data->enable = enable; |
|
data->count = -1; |
|
data->file = file; |
|
|
|
if (!param) |
|
goto out_reg; |
|
|
|
number = strsep(¶m, ":"); |
|
|
|
ret = -EINVAL; |
|
if (!strlen(number)) |
|
goto out_free; |
|
|
|
/* |
|
* We use the callback data field (which is a pointer) |
|
* as our counter. |
|
*/ |
|
ret = kstrtoul(number, 0, &data->count); |
|
if (ret) |
|
goto out_free; |
|
|
|
out_reg: |
|
/* Don't let event modules unload while probe registered */ |
|
ret = try_module_get(file->event_call->mod); |
|
if (!ret) { |
|
ret = -EBUSY; |
|
goto out_free; |
|
} |
|
|
|
ret = __ftrace_event_enable_disable(file, 1, 1); |
|
if (ret < 0) |
|
goto out_put; |
|
|
|
ret = register_ftrace_function_probe(glob, tr, ops, data); |
|
/* |
|
* The above returns on success the # of functions enabled, |
|
* but if it didn't find any functions it returns zero. |
|
* Consider no functions a failure too. |
|
*/ |
|
if (!ret) { |
|
ret = -ENOENT; |
|
goto out_disable; |
|
} else if (ret < 0) |
|
goto out_disable; |
|
/* Just return zero, not the number of enabled functions */ |
|
ret = 0; |
|
out: |
|
mutex_unlock(&event_mutex); |
|
return ret; |
|
|
|
out_disable: |
|
__ftrace_event_enable_disable(file, 0, 1); |
|
out_put: |
|
module_put(file->event_call->mod); |
|
out_free: |
|
kfree(data); |
|
goto out; |
|
} |
|
|
|
static struct ftrace_func_command event_enable_cmd = { |
|
.name = ENABLE_EVENT_STR, |
|
.func = event_enable_func, |
|
}; |
|
|
|
static struct ftrace_func_command event_disable_cmd = { |
|
.name = DISABLE_EVENT_STR, |
|
.func = event_enable_func, |
|
}; |
|
|
|
static __init int register_event_cmds(void) |
|
{ |
|
int ret; |
|
|
|
ret = register_ftrace_command(&event_enable_cmd); |
|
if (WARN_ON(ret < 0)) |
|
return ret; |
|
ret = register_ftrace_command(&event_disable_cmd); |
|
if (WARN_ON(ret < 0)) |
|
unregister_ftrace_command(&event_enable_cmd); |
|
return ret; |
|
} |
|
#else |
|
static inline int register_event_cmds(void) { return 0; } |
|
#endif /* CONFIG_DYNAMIC_FTRACE */ |
|
|
|
/* |
|
* The top level array and trace arrays created by boot-time tracing |
|
* have already had its trace_event_file descriptors created in order |
|
* to allow for early events to be recorded. |
|
* This function is called after the tracefs has been initialized, |
|
* and we now have to create the files associated to the events. |
|
*/ |
|
static void __trace_early_add_event_dirs(struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file; |
|
int ret; |
|
|
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
ret = event_create_dir(tr->event_dir, file); |
|
if (ret < 0) |
|
pr_warn("Could not create directory for event %s\n", |
|
trace_event_name(file->event_call)); |
|
} |
|
} |
|
|
|
/* |
|
* For early boot up, the top trace array and the trace arrays created |
|
* by boot-time tracing require to have a list of events that can be |
|
* enabled. This must be done before the filesystem is set up in order |
|
* to allow events to be traced early. |
|
*/ |
|
void __trace_early_add_events(struct trace_array *tr) |
|
{ |
|
struct trace_event_call *call; |
|
int ret; |
|
|
|
list_for_each_entry(call, &ftrace_events, list) { |
|
/* Early boot up should not have any modules loaded */ |
|
if (WARN_ON_ONCE(call->mod)) |
|
continue; |
|
|
|
ret = __trace_early_add_new_event(call, tr); |
|
if (ret < 0) |
|
pr_warn("Could not create early event %s\n", |
|
trace_event_name(call)); |
|
} |
|
} |
|
|
|
/* Remove the event directory structure for a trace directory. */ |
|
static void |
|
__trace_remove_event_dirs(struct trace_array *tr) |
|
{ |
|
struct trace_event_file *file, *next; |
|
|
|
list_for_each_entry_safe(file, next, &tr->events, list) |
|
remove_event_file_dir(file); |
|
} |
|
|
|
static void __add_event_to_tracers(struct trace_event_call *call) |
|
{ |
|
struct trace_array *tr; |
|
|
|
list_for_each_entry(tr, &ftrace_trace_arrays, list) |
|
__trace_add_new_event(call, tr); |
|
} |
|
|
|
extern struct trace_event_call *__start_ftrace_events[]; |
|
extern struct trace_event_call *__stop_ftrace_events[]; |
|
|
|
static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata; |
|
|
|
static __init int setup_trace_event(char *str) |
|
{ |
|
strlcpy(bootup_event_buf, str, COMMAND_LINE_SIZE); |
|
ring_buffer_expanded = true; |
|
disable_tracing_selftest("running event tracing"); |
|
|
|
return 1; |
|
} |
|
__setup("trace_event=", setup_trace_event); |
|
|
|
/* Expects to have event_mutex held when called */ |
|
static int |
|
create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) |
|
{ |
|
struct dentry *d_events; |
|
struct dentry *entry; |
|
|
|
entry = tracefs_create_file("set_event", 0644, parent, |
|
tr, &ftrace_set_event_fops); |
|
if (!entry) { |
|
pr_warn("Could not create tracefs 'set_event' entry\n"); |
|
return -ENOMEM; |
|
} |
|
|
|
d_events = tracefs_create_dir("events", parent); |
|
if (!d_events) { |
|
pr_warn("Could not create tracefs 'events' directory\n"); |
|
return -ENOMEM; |
|
} |
|
|
|
entry = trace_create_file("enable", 0644, d_events, |
|
tr, &ftrace_tr_enable_fops); |
|
if (!entry) { |
|
pr_warn("Could not create tracefs 'enable' entry\n"); |
|
return -ENOMEM; |
|
} |
|
|
|
/* There are not as crucial, just warn if they are not created */ |
|
|
|
entry = tracefs_create_file("set_event_pid", 0644, parent, |
|
tr, &ftrace_set_event_pid_fops); |
|
if (!entry) |
|
pr_warn("Could not create tracefs 'set_event_pid' entry\n"); |
|
|
|
entry = tracefs_create_file("set_event_notrace_pid", 0644, parent, |
|
tr, &ftrace_set_event_notrace_pid_fops); |
|
if (!entry) |
|
pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n"); |
|
|
|
/* ring buffer internal formats */ |
|
entry = trace_create_file("header_page", 0444, d_events, |
|
ring_buffer_print_page_header, |
|
&ftrace_show_header_fops); |
|
if (!entry) |
|
pr_warn("Could not create tracefs 'header_page' entry\n"); |
|
|
|
entry = trace_create_file("header_event", 0444, d_events, |
|
ring_buffer_print_entry_header, |
|
&ftrace_show_header_fops); |
|
if (!entry) |
|
pr_warn("Could not create tracefs 'header_event' entry\n"); |
|
|
|
tr->event_dir = d_events; |
|
|
|
return 0; |
|
} |
|
|
|
/** |
|
* event_trace_add_tracer - add a instance of a trace_array to events |
|
* @parent: The parent dentry to place the files/directories for events in |
|
* @tr: The trace array associated with these events |
|
* |
|
* When a new instance is created, it needs to set up its events |
|
* directory, as well as other files associated with events. It also |
|
* creates the event hierarchy in the @parent/events directory. |
|
* |
|
* Returns 0 on success. |
|
* |
|
* Must be called with event_mutex held. |
|
*/ |
|
int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr) |
|
{ |
|
int ret; |
|
|
|
lockdep_assert_held(&event_mutex); |
|
|
|
ret = create_event_toplevel_files(parent, tr); |
|
if (ret) |
|
goto out; |
|
|
|
down_write(&trace_event_sem); |
|
/* If tr already has the event list, it is initialized in early boot. */ |
|
if (unlikely(!list_empty(&tr->events))) |
|
__trace_early_add_event_dirs(tr); |
|
else |
|
__trace_add_event_dirs(tr); |
|
up_write(&trace_event_sem); |
|
|
|
out: |
|
return ret; |
|
} |
|
|
|
/* |
|
* The top trace array already had its file descriptors created. |
|
* Now the files themselves need to be created. |
|
*/ |
|
static __init int |
|
early_event_add_tracer(struct dentry *parent, struct trace_array *tr) |
|
{ |
|
int ret; |
|
|
|
mutex_lock(&event_mutex); |
|
|
|
ret = create_event_toplevel_files(parent, tr); |
|
if (ret) |
|
goto out_unlock; |
|
|
|
down_write(&trace_event_sem); |
|
__trace_early_add_event_dirs(tr); |
|
up_write(&trace_event_sem); |
|
|
|
out_unlock: |
|
mutex_unlock(&event_mutex); |
|
|
|
return ret; |
|
} |
|
|
|
/* Must be called with event_mutex held */ |
|
int event_trace_del_tracer(struct trace_array *tr) |
|
{ |
|
lockdep_assert_held(&event_mutex); |
|
|
|
/* Disable any event triggers and associated soft-disabled events */ |
|
clear_event_triggers(tr); |
|
|
|
/* Clear the pid list */ |
|
__ftrace_clear_event_pids(tr, TRACE_PIDS | TRACE_NO_PIDS); |
|
|
|
/* Disable any running events */ |
|
__ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); |
|
|
|
/* Make sure no more events are being executed */ |
|
tracepoint_synchronize_unregister(); |
|
|
|
down_write(&trace_event_sem); |
|
__trace_remove_event_dirs(tr); |
|
tracefs_remove(tr->event_dir); |
|
up_write(&trace_event_sem); |
|
|
|
tr->event_dir = NULL; |
|
|
|
return 0; |
|
} |
|
|
|
static __init int event_trace_memsetup(void) |
|
{ |
|
field_cachep = KMEM_CACHE(ftrace_event_field, SLAB_PANIC); |
|
file_cachep = KMEM_CACHE(trace_event_file, SLAB_PANIC); |
|
return 0; |
|
} |
|
|
|
static __init void |
|
early_enable_events(struct trace_array *tr, bool disable_first) |
|
{ |
|
char *buf = bootup_event_buf; |
|
char *token; |
|
int ret; |
|
|
|
while (true) { |
|
token = strsep(&buf, ","); |
|
|
|
if (!token) |
|
break; |
|
|
|
if (*token) { |
|
/* Restarting syscalls requires that we stop them first */ |
|
if (disable_first) |
|
ftrace_set_clr_event(tr, token, 0); |
|
|
|
ret = ftrace_set_clr_event(tr, token, 1); |
|
if (ret) |
|
pr_warn("Failed to enable trace event: %s\n", token); |
|
} |
|
|
|
/* Put back the comma to allow this to be called again */ |
|
if (buf) |
|
*(buf - 1) = ','; |
|
} |
|
} |
|
|
|
static __init int event_trace_enable(void) |
|
{ |
|
struct trace_array *tr = top_trace_array(); |
|
struct trace_event_call **iter, *call; |
|
int ret; |
|
|
|
if (!tr) |
|
return -ENODEV; |
|
|
|
for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) { |
|
|
|
call = *iter; |
|
ret = event_init(call); |
|
if (!ret) |
|
list_add(&call->list, &ftrace_events); |
|
} |
|
|
|
/* |
|
* We need the top trace array to have a working set of trace |
|
* points at early init, before the debug files and directories |
|
* are created. Create the file entries now, and attach them |
|
* to the actual file dentries later. |
|
*/ |
|
__trace_early_add_events(tr); |
|
|
|
early_enable_events(tr, false); |
|
|
|
trace_printk_start_comm(); |
|
|
|
register_event_cmds(); |
|
|
|
register_trigger_cmds(); |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* event_trace_enable() is called from trace_event_init() first to |
|
* initialize events and perhaps start any events that are on the |
|
* command line. Unfortunately, there are some events that will not |
|
* start this early, like the system call tracepoints that need |
|
* to set the %SYSCALL_WORK_SYSCALL_TRACEPOINT flag of pid 1. But |
|
* event_trace_enable() is called before pid 1 starts, and this flag |
|
* is never set, making the syscall tracepoint never get reached, but |
|
* the event is enabled regardless (and not doing anything). |
|
*/ |
|
static __init int event_trace_enable_again(void) |
|
{ |
|
struct trace_array *tr; |
|
|
|
tr = top_trace_array(); |
|
if (!tr) |
|
return -ENODEV; |
|
|
|
early_enable_events(tr, true); |
|
|
|
return 0; |
|
} |
|
|
|
early_initcall(event_trace_enable_again); |
|
|
|
/* Init fields which doesn't related to the tracefs */ |
|
static __init int event_trace_init_fields(void) |
|
{ |
|
if (trace_define_generic_fields()) |
|
pr_warn("tracing: Failed to allocated generic fields"); |
|
|
|
if (trace_define_common_fields()) |
|
pr_warn("tracing: Failed to allocate common fields"); |
|
|
|
return 0; |
|
} |
|
|
|
__init int event_trace_init(void) |
|
{ |
|
struct trace_array *tr; |
|
struct dentry *entry; |
|
int ret; |
|
|
|
tr = top_trace_array(); |
|
if (!tr) |
|
return -ENODEV; |
|
|
|
entry = tracefs_create_file("available_events", 0444, NULL, |
|
tr, &ftrace_avail_fops); |
|
if (!entry) |
|
pr_warn("Could not create tracefs 'available_events' entry\n"); |
|
|
|
ret = early_event_add_tracer(NULL, tr); |
|
if (ret) |
|
return ret; |
|
|
|
#ifdef CONFIG_MODULES |
|
ret = register_module_notifier(&trace_module_nb); |
|
if (ret) |
|
pr_warn("Failed to register trace events module notifier\n"); |
|
#endif |
|
|
|
eventdir_initialized = true; |
|
|
|
return 0; |
|
} |
|
|
|
void __init trace_event_init(void) |
|
{ |
|
event_trace_memsetup(); |
|
init_ftrace_syscalls(); |
|
event_trace_enable(); |
|
event_trace_init_fields(); |
|
} |
|
|
|
#ifdef CONFIG_EVENT_TRACE_STARTUP_TEST |
|
|
|
static DEFINE_SPINLOCK(test_spinlock); |
|
static DEFINE_SPINLOCK(test_spinlock_irq); |
|
static DEFINE_MUTEX(test_mutex); |
|
|
|
static __init void test_work(struct work_struct *dummy) |
|
{ |
|
spin_lock(&test_spinlock); |
|
spin_lock_irq(&test_spinlock_irq); |
|
udelay(1); |
|
spin_unlock_irq(&test_spinlock_irq); |
|
spin_unlock(&test_spinlock); |
|
|
|
mutex_lock(&test_mutex); |
|
msleep(1); |
|
mutex_unlock(&test_mutex); |
|
} |
|
|
|
static __init int event_test_thread(void *unused) |
|
{ |
|
void *test_malloc; |
|
|
|
test_malloc = kmalloc(1234, GFP_KERNEL); |
|
if (!test_malloc) |
|
pr_info("failed to kmalloc\n"); |
|
|
|
schedule_on_each_cpu(test_work); |
|
|
|
kfree(test_malloc); |
|
|
|
set_current_state(TASK_INTERRUPTIBLE); |
|
while (!kthread_should_stop()) { |
|
schedule(); |
|
set_current_state(TASK_INTERRUPTIBLE); |
|
} |
|
__set_current_state(TASK_RUNNING); |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Do various things that may trigger events. |
|
*/ |
|
static __init void event_test_stuff(void) |
|
{ |
|
struct task_struct *test_thread; |
|
|
|
test_thread = kthread_run(event_test_thread, NULL, "test-events"); |
|
msleep(1); |
|
kthread_stop(test_thread); |
|
} |
|
|
|
/* |
|
* For every trace event defined, we will test each trace point separately, |
|
* and then by groups, and finally all trace points. |
|
*/ |
|
static __init void event_trace_self_tests(void) |
|
{ |
|
struct trace_subsystem_dir *dir; |
|
struct trace_event_file *file; |
|
struct trace_event_call *call; |
|
struct event_subsystem *system; |
|
struct trace_array *tr; |
|
int ret; |
|
|
|
tr = top_trace_array(); |
|
if (!tr) |
|
return; |
|
|
|
pr_info("Running tests on trace events:\n"); |
|
|
|
list_for_each_entry(file, &tr->events, list) { |
|
|
|
call = file->event_call; |
|
|
|
/* Only test those that have a probe */ |
|
if (!call->class || !call->class->probe) |
|
continue; |
|
|
|
/* |
|
* Testing syscall events here is pretty useless, but |
|
* we still do it if configured. But this is time consuming. |
|
* What we really need is a user thread to perform the |
|
* syscalls as we test. |
|
*/ |
|
#ifndef CONFIG_EVENT_TRACE_TEST_SYSCALLS |
|
if (call->class->system && |
|
strcmp(call->class->system, "syscalls") == 0) |
|
continue; |
|
#endif |
|
|
|
pr_info("Testing event %s: ", trace_event_name(call)); |
|
|
|
/* |
|
* If an event is already enabled, someone is using |
|
* it and the self test should not be on. |
|
*/ |
|
if (file->flags & EVENT_FILE_FL_ENABLED) { |
|
pr_warn("Enabled event during self test!\n"); |
|
WARN_ON_ONCE(1); |
|
continue; |
|
} |
|
|
|
ftrace_event_enable_disable(file, 1); |
|
event_test_stuff(); |
|
ftrace_event_enable_disable(file, 0); |
|
|
|
pr_cont("OK\n"); |
|
} |
|
|
|
/* Now test at the sub system level */ |
|
|
|
pr_info("Running tests on trace event systems:\n"); |
|
|
|
list_for_each_entry(dir, &tr->systems, list) { |
|
|
|
system = dir->subsystem; |
|
|
|
/* the ftrace system is special, skip it */ |
|
if (strcmp(system->name, "ftrace") == 0) |
|
continue; |
|
|
|
pr_info("Testing event system %s: ", system->name); |
|
|
|
ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 1); |
|
if (WARN_ON_ONCE(ret)) { |
|
pr_warn("error enabling system %s\n", |
|
system->name); |
|
continue; |
|
} |
|
|
|
event_test_stuff(); |
|
|
|
ret = __ftrace_set_clr_event(tr, NULL, system->name, NULL, 0); |
|
if (WARN_ON_ONCE(ret)) { |
|
pr_warn("error disabling system %s\n", |
|
system->name); |
|
continue; |
|
} |
|
|
|
pr_cont("OK\n"); |
|
} |
|
|
|
/* Test with all events enabled */ |
|
|
|
pr_info("Running tests on all trace events:\n"); |
|
pr_info("Testing all events: "); |
|
|
|
ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 1); |
|
if (WARN_ON_ONCE(ret)) { |
|
pr_warn("error enabling all events\n"); |
|
return; |
|
} |
|
|
|
event_test_stuff(); |
|
|
|
/* reset sysname */ |
|
ret = __ftrace_set_clr_event(tr, NULL, NULL, NULL, 0); |
|
if (WARN_ON_ONCE(ret)) { |
|
pr_warn("error disabling all events\n"); |
|
return; |
|
} |
|
|
|
pr_cont("OK\n"); |
|
} |
|
|
|
#ifdef CONFIG_FUNCTION_TRACER |
|
|
|
static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable); |
|
|
|
static struct trace_event_file event_trace_file __initdata; |
|
|
|
static void __init |
|
function_test_events_call(unsigned long ip, unsigned long parent_ip, |
|
struct ftrace_ops *op, struct ftrace_regs *regs) |
|
{ |
|
struct trace_buffer *buffer; |
|
struct ring_buffer_event *event; |
|
struct ftrace_entry *entry; |
|
unsigned int trace_ctx; |
|
long disabled; |
|
int cpu; |
|
|
|
trace_ctx = tracing_gen_ctx(); |
|
preempt_disable_notrace(); |
|
cpu = raw_smp_processor_id(); |
|
disabled = atomic_inc_return(&per_cpu(ftrace_test_event_disable, cpu)); |
|
|
|
if (disabled != 1) |
|
goto out; |
|
|
|
event = trace_event_buffer_lock_reserve(&buffer, &event_trace_file, |
|
TRACE_FN, sizeof(*entry), |
|
trace_ctx); |
|
if (!event) |
|
goto out; |
|
entry = ring_buffer_event_data(event); |
|
entry->ip = ip; |
|
entry->parent_ip = parent_ip; |
|
|
|
event_trigger_unlock_commit(&event_trace_file, buffer, event, |
|
entry, trace_ctx); |
|
out: |
|
atomic_dec(&per_cpu(ftrace_test_event_disable, cpu)); |
|
preempt_enable_notrace(); |
|
} |
|
|
|
static struct ftrace_ops trace_ops __initdata = |
|
{ |
|
.func = function_test_events_call, |
|
}; |
|
|
|
static __init void event_trace_self_test_with_function(void) |
|
{ |
|
int ret; |
|
|
|
event_trace_file.tr = top_trace_array(); |
|
if (WARN_ON(!event_trace_file.tr)) |
|
return; |
|
|
|
ret = register_ftrace_function(&trace_ops); |
|
if (WARN_ON(ret < 0)) { |
|
pr_info("Failed to enable function tracer for event tests\n"); |
|
return; |
|
} |
|
pr_info("Running tests again, along with the function tracer\n"); |
|
event_trace_self_tests(); |
|
unregister_ftrace_function(&trace_ops); |
|
} |
|
#else |
|
static __init void event_trace_self_test_with_function(void) |
|
{ |
|
} |
|
#endif |
|
|
|
static __init int event_trace_self_tests_init(void) |
|
{ |
|
if (!tracing_selftest_disabled) { |
|
event_trace_self_tests(); |
|
event_trace_self_test_with_function(); |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
late_initcall(event_trace_self_tests_init); |
|
|
|
#endif
|
|
|