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.
51 lines
1.2 KiB
51 lines
1.2 KiB
/* SPDX-License-Identifier: GPL-2.0 */ |
|
#ifndef __LINUX_COOKIE_H |
|
#define __LINUX_COOKIE_H |
|
|
|
#include <linux/atomic.h> |
|
#include <linux/percpu.h> |
|
#include <asm/local.h> |
|
|
|
struct pcpu_gen_cookie { |
|
local_t nesting; |
|
u64 last; |
|
} __aligned(16); |
|
|
|
struct gen_cookie { |
|
struct pcpu_gen_cookie __percpu *local; |
|
atomic64_t forward_last ____cacheline_aligned_in_smp; |
|
atomic64_t reverse_last; |
|
}; |
|
|
|
#define COOKIE_LOCAL_BATCH 4096 |
|
|
|
#define DEFINE_COOKIE(name) \ |
|
static DEFINE_PER_CPU(struct pcpu_gen_cookie, __##name); \ |
|
static struct gen_cookie name = { \ |
|
.local = &__##name, \ |
|
.forward_last = ATOMIC64_INIT(0), \ |
|
.reverse_last = ATOMIC64_INIT(0), \ |
|
} |
|
|
|
static __always_inline u64 gen_cookie_next(struct gen_cookie *gc) |
|
{ |
|
struct pcpu_gen_cookie *local = this_cpu_ptr(gc->local); |
|
u64 val; |
|
|
|
if (likely(local_inc_return(&local->nesting) == 1)) { |
|
val = local->last; |
|
if (__is_defined(CONFIG_SMP) && |
|
unlikely((val & (COOKIE_LOCAL_BATCH - 1)) == 0)) { |
|
s64 next = atomic64_add_return(COOKIE_LOCAL_BATCH, |
|
&gc->forward_last); |
|
val = next - COOKIE_LOCAL_BATCH; |
|
} |
|
local->last = ++val; |
|
} else { |
|
val = atomic64_dec_return(&gc->reverse_last); |
|
} |
|
local_dec(&local->nesting); |
|
return val; |
|
} |
|
|
|
#endif /* __LINUX_COOKIE_H */
|
|
|