diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-13 10:27:28 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-04-13 10:27:28 -0700 |
commit | cc76ee75a9d3201eeacc576d17fbc1511f673010 (patch) | |
tree | 9505405c270718c491840ae7d0da0521386ce939 /include | |
parent | 9c65e12a55fea2da50f4069ec0dc47c50b7bd2bb (diff) | |
parent | 58995a9a5b292458f94a2356b8c878230fa56fe0 (diff) |
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core locking changes from Ingo Molnar:
"Main changes:
- jump label asm preparatory work for PowerPC (Anton Blanchard)
- rwsem optimizations and cleanups (Davidlohr Bueso)
- mutex optimizations and cleanups (Jason Low)
- futex fix (Oleg Nesterov)
- remove broken atomicity checks from {READ,WRITE}_ONCE() (Peter
Zijlstra)"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
powerpc, jump_label: Include linux/jump_label.h to get HAVE_JUMP_LABEL define
jump_label: Allow jump labels to be used in assembly
jump_label: Allow asm/jump_label.h to be included in assembly
locking/mutex: Further simplify mutex_spin_on_owner()
locking: Remove atomicy checks from {READ,WRITE}_ONCE
locking/rtmutex: Rename argument in the rt_mutex_adjust_prio_chain() documentation as well
locking/rwsem: Fix lock optimistic spinning when owner is not running
locking: Remove ACCESS_ONCE() usage
locking/rwsem: Check for active lock before bailing on spinning
locking/rwsem: Avoid deceiving lock spinners
locking/rwsem: Set lock ownership ASAP
locking/rwsem: Document barrier need when waking tasks
locking/futex: Check PF_KTHREAD rather than !p->mm to filter out kthreads
locking/mutex: Refactor mutex_spin_on_owner()
locking/mutex: In mutex_spin_on_owner(), return true when owner changes
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/compiler.h | 16 | ||||
-rw-r--r-- | include/linux/jump_label.h | 21 | ||||
-rw-r--r-- | include/linux/seqlock.h | 6 |
3 files changed, 20 insertions, 23 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h index 1b45e4a0519b..0e41ca0e5927 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -192,29 +192,16 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect); #include <uapi/linux/types.h> -static __always_inline void data_access_exceeds_word_size(void) -#ifdef __compiletime_warning -__compiletime_warning("data access exceeds word size and won't be atomic") -#endif -; - -static __always_inline void data_access_exceeds_word_size(void) -{ -} - static __always_inline void __read_once_size(const volatile void *p, void *res, int size) { switch (size) { case 1: *(__u8 *)res = *(volatile __u8 *)p; break; case 2: *(__u16 *)res = *(volatile __u16 *)p; break; case 4: *(__u32 *)res = *(volatile __u32 *)p; break; -#ifdef CONFIG_64BIT case 8: *(__u64 *)res = *(volatile __u64 *)p; break; -#endif default: barrier(); __builtin_memcpy((void *)res, (const void *)p, size); - data_access_exceeds_word_size(); barrier(); } } @@ -225,13 +212,10 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s case 1: *(volatile __u8 *)p = *(__u8 *)res; break; case 2: *(volatile __u16 *)p = *(__u16 *)res; break; case 4: *(volatile __u32 *)p = *(__u32 *)res; break; -#ifdef CONFIG_64BIT case 8: *(volatile __u64 *)p = *(__u64 *)res; break; -#endif default: barrier(); __builtin_memcpy((void *)p, (const void *)res, size); - data_access_exceeds_word_size(); barrier(); } } diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 98f923b6a0ea..f4de473f226b 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -45,6 +45,12 @@ * same as using STATIC_KEY_INIT_FALSE. */ +#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) +# define HAVE_JUMP_LABEL +#endif + +#ifndef __ASSEMBLY__ + #include <linux/types.h> #include <linux/compiler.h> #include <linux/bug.h> @@ -55,7 +61,7 @@ extern bool static_key_initialized; "%s used before call to jump_label_init", \ __func__) -#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) +#ifdef HAVE_JUMP_LABEL struct static_key { atomic_t enabled; @@ -66,13 +72,18 @@ struct static_key { #endif }; -# include <asm/jump_label.h> -# define HAVE_JUMP_LABEL #else struct static_key { atomic_t enabled; }; -#endif /* CC_HAVE_ASM_GOTO && CONFIG_JUMP_LABEL */ +#endif /* HAVE_JUMP_LABEL */ +#endif /* __ASSEMBLY__ */ + +#ifdef HAVE_JUMP_LABEL +#include <asm/jump_label.h> +#endif + +#ifndef __ASSEMBLY__ enum jump_label_type { JUMP_LABEL_DISABLE = 0, @@ -203,3 +214,5 @@ static inline bool static_key_enabled(struct static_key *key) } #endif /* _LINUX_JUMP_LABEL_H */ + +#endif /* __ASSEMBLY__ */ diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index f5df8f687b4d..5f68d0a391ce 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -108,7 +108,7 @@ static inline unsigned __read_seqcount_begin(const seqcount_t *s) unsigned ret; repeat: - ret = ACCESS_ONCE(s->sequence); + ret = READ_ONCE(s->sequence); if (unlikely(ret & 1)) { cpu_relax(); goto repeat; @@ -127,7 +127,7 @@ repeat: */ static inline unsigned raw_read_seqcount(const seqcount_t *s) { - unsigned ret = ACCESS_ONCE(s->sequence); + unsigned ret = READ_ONCE(s->sequence); smp_rmb(); return ret; } @@ -179,7 +179,7 @@ static inline unsigned read_seqcount_begin(const seqcount_t *s) */ static inline unsigned raw_seqcount_begin(const seqcount_t *s) { - unsigned ret = ACCESS_ONCE(s->sequence); + unsigned ret = READ_ONCE(s->sequence); smp_rmb(); return ret & ~1; } |