mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 04:34:11 +08:00
da6d856751
Uses the arch/x86/ kernel code for x86_64/i386, fallbacking to a gcc intrinsics implementation that has been tested in at least sparc64. Will be used for reference counting in tools/perf. Acked-by: David Ahern <dsahern@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-knfpjowhgyh6x4z0kfuk389j@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
64 lines
1.3 KiB
C
64 lines
1.3 KiB
C
#ifndef __TOOLS_ASM_GENERIC_ATOMIC_H
|
|
#define __TOOLS_ASM_GENERIC_ATOMIC_H
|
|
|
|
#include <linux/compiler.h>
|
|
#include <linux/types.h>
|
|
|
|
/*
|
|
* Atomic operations that C can't guarantee us. Useful for
|
|
* resource counting etc..
|
|
*
|
|
* Excerpts obtained from the Linux kernel sources.
|
|
*/
|
|
|
|
#define ATOMIC_INIT(i) { (i) }
|
|
|
|
/**
|
|
* atomic_read - read atomic variable
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically reads the value of @v.
|
|
*/
|
|
static inline int atomic_read(const atomic_t *v)
|
|
{
|
|
return ACCESS_ONCE((v)->counter);
|
|
}
|
|
|
|
/**
|
|
* atomic_set - set atomic variable
|
|
* @v: pointer of type atomic_t
|
|
* @i: required value
|
|
*
|
|
* Atomically sets the value of @v to @i.
|
|
*/
|
|
static inline void atomic_set(atomic_t *v, int i)
|
|
{
|
|
v->counter = i;
|
|
}
|
|
|
|
/**
|
|
* atomic_inc - increment atomic variable
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically increments @v by 1.
|
|
*/
|
|
static inline void atomic_inc(atomic_t *v)
|
|
{
|
|
__sync_add_and_fetch(&v->counter, 1);
|
|
}
|
|
|
|
/**
|
|
* atomic_dec_and_test - decrement and test
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically decrements @v by 1 and
|
|
* returns true if the result is 0, or false for all other
|
|
* cases.
|
|
*/
|
|
static inline int atomic_dec_and_test(atomic_t *v)
|
|
{
|
|
return __sync_sub_and_fetch(&v->counter, 1) == 0;
|
|
}
|
|
|
|
#endif /* __TOOLS_ASM_GENERIC_ATOMIC_H */
|