mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
98 lines
2.2 KiB
98 lines
2.2 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
// Copyright (c) 2019 Facebook |
|
#include "vmlinux.h" |
|
#include <bpf/bpf_helpers.h> |
|
#include "runqslower.h" |
|
|
|
#define TASK_RUNNING 0 |
|
#define BPF_F_CURRENT_CPU 0xffffffffULL |
|
|
|
const volatile __u64 min_us = 0; |
|
const volatile pid_t targ_pid = 0; |
|
|
|
struct { |
|
__uint(type, BPF_MAP_TYPE_HASH); |
|
__uint(max_entries, 10240); |
|
__type(key, u32); |
|
__type(value, u64); |
|
} start SEC(".maps"); |
|
|
|
struct { |
|
__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); |
|
__uint(key_size, sizeof(u32)); |
|
__uint(value_size, sizeof(u32)); |
|
} events SEC(".maps"); |
|
|
|
/* record enqueue timestamp */ |
|
__always_inline |
|
static int trace_enqueue(u32 tgid, u32 pid) |
|
{ |
|
u64 ts; |
|
|
|
if (!pid || (targ_pid && targ_pid != pid)) |
|
return 0; |
|
|
|
ts = bpf_ktime_get_ns(); |
|
bpf_map_update_elem(&start, &pid, &ts, 0); |
|
return 0; |
|
} |
|
|
|
SEC("tp_btf/sched_wakeup") |
|
int handle__sched_wakeup(u64 *ctx) |
|
{ |
|
/* TP_PROTO(struct task_struct *p) */ |
|
struct task_struct *p = (void *)ctx[0]; |
|
|
|
return trace_enqueue(p->tgid, p->pid); |
|
} |
|
|
|
SEC("tp_btf/sched_wakeup_new") |
|
int handle__sched_wakeup_new(u64 *ctx) |
|
{ |
|
/* TP_PROTO(struct task_struct *p) */ |
|
struct task_struct *p = (void *)ctx[0]; |
|
|
|
return trace_enqueue(p->tgid, p->pid); |
|
} |
|
|
|
SEC("tp_btf/sched_switch") |
|
int handle__sched_switch(u64 *ctx) |
|
{ |
|
/* TP_PROTO(bool preempt, struct task_struct *prev, |
|
* struct task_struct *next) |
|
*/ |
|
struct task_struct *prev = (struct task_struct *)ctx[1]; |
|
struct task_struct *next = (struct task_struct *)ctx[2]; |
|
struct event event = {}; |
|
u64 *tsp, delta_us; |
|
long state; |
|
u32 pid; |
|
|
|
/* ivcsw: treat like an enqueue event and store timestamp */ |
|
if (prev->state == TASK_RUNNING) |
|
trace_enqueue(prev->tgid, prev->pid); |
|
|
|
pid = next->pid; |
|
|
|
/* fetch timestamp and calculate delta */ |
|
tsp = bpf_map_lookup_elem(&start, &pid); |
|
if (!tsp) |
|
return 0; /* missed enqueue */ |
|
|
|
delta_us = (bpf_ktime_get_ns() - *tsp) / 1000; |
|
if (min_us && delta_us <= min_us) |
|
return 0; |
|
|
|
event.pid = pid; |
|
event.delta_us = delta_us; |
|
bpf_get_current_comm(&event.task, sizeof(event.task)); |
|
|
|
/* output */ |
|
bpf_perf_event_output(ctx, &events, BPF_F_CURRENT_CPU, |
|
&event, sizeof(event)); |
|
|
|
bpf_map_delete_elem(&start, &pid); |
|
return 0; |
|
} |
|
|
|
char LICENSE[] SEC("license") = "GPL";
|
|
|