ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 04:33:26 +02:00
Code Issues Packages Projects Releases Wiki Activity

Merge tag 'locking-core-2023-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Browse Source 
Pull locking updates from Ingo Molnar:

 - Introduce local{,64}_try_cmpxchg() - a slightly more optimal
   primitive, which will be used in perf events ring-buffer code

 - Simplify/modify rwsems on PREEMPT_RT, to address writer starvation

 - Misc cleanups/fixes

* tag 'locking-core-2023-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/atomic: Correct (cmp)xchg() instrumentation
  locking/x86: Define arch_try_cmpxchg_local()
  locking/arch: Wire up local_try_cmpxchg()
  locking/generic: Wire up local{,64}_try_cmpxchg()
  locking/atomic: Add generic try_cmpxchg{,64}_local() support
  locking/rwbase: Mitigate indefinite writer starvation
  locking/arch: Rename all internal __xchg() names to __arch_xchg()
This commit is contained in:
Linus Torvalds
2023-05-05 12:56:55 -07:00
parent d5ed10bb80 ec570320b0
commit b115d85a95
33 changed files with 209 additions and 111 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
arch/alpha/include/asm/cmpxchg.h
View File

@@ -6,15 +6,15 @@
* Atomic exchange routines.
*/
#define ____xchg(type, args...) __xchg ## type ## _local(args)
#define ____xchg(type, args...) __arch_xchg ## type ## _local(args)
#define ____cmpxchg(type, args...) __cmpxchg ## type ## _local(args)
#include <asm/xchg.h>
#define xchg_local(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg_local((ptr), (unsigned long)_x_, \
sizeof(*(ptr))); \
(__typeof__(*(ptr))) __arch_xchg_local((ptr), (unsigned long)_x_,\
sizeof(*(ptr))); \
})
#define arch_cmpxchg_local(ptr, o, n) \
@@ -34,7 +34,7 @@
#undef ____xchg
#undef ____cmpxchg
#define ____xchg(type, args...) __xchg ##type(args)
#define ____xchg(type, args...) __arch_xchg ##type(args)
#define ____cmpxchg(type, args...) __cmpxchg ##type(args)
#include <asm/xchg.h>
@@ -48,7 +48,7 @@
__typeof__(*(ptr)) _x_ = (x); \
smp_mb(); \
__ret = (__typeof__(*(ptr))) \
__xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
__arch_xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
smp_mb(); \
__ret; \
})

12
arch/alpha/include/asm/local.h
View File

@@ -52,8 +52,16 @@ static __inline__ long local_sub_return(long i, local_t * l)
return result;
}
#define local_cmpxchg(l, o, n) \
(cmpxchg_local(&((l)->a.counter), (o), (n)))
static __inline__ long local_cmpxchg(local_t *l, long old, long new)
{
return cmpxchg_local(&l->a.counter, old, new);
}
static __inline__ bool local_try_cmpxchg(local_t *l, long *old, long new)
{
return try_cmpxchg_local(&l->a.counter, (s64 *)old, new);
}
#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
/**