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author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-25 22:41:29 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-07-25 22:41:29 +0300 |
commit | c86ad14d305d2429c3da19462440bac50c183def (patch) | |
tree | bd794cd72476661faf82c440063c217bb978ce44 /arch/xtensa | |
parent | a2303849a6b4b7ba59667091e00d6bb194071d9a (diff) | |
parent | f06628638cf6e75f179742b6c1b35076965b9fdd (diff) | |
download | linux-c86ad14d305d2429c3da19462440bac50c183def.tar.xz |
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
"The locking tree was busier in this cycle than the usual pattern - a
couple of major projects happened to coincide.
The main changes are:
- implement the atomic_fetch_{add,sub,and,or,xor}() API natively
across all SMP architectures (Peter Zijlstra)
- add atomic_fetch_{inc/dec}() as well, using the generic primitives
(Davidlohr Bueso)
- optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
Waiman Long)
- optimize smp_cond_load_acquire() on arm64 and implement LSE based
atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
on arm64 (Will Deacon)
- introduce smp_acquire__after_ctrl_dep() and fix various barrier
mis-uses and bugs (Peter Zijlstra)
- after discovering ancient spin_unlock_wait() barrier bugs in its
implementation and usage, strengthen its semantics and update/fix
usage sites (Peter Zijlstra)
- optimize mutex_trylock() fastpath (Peter Zijlstra)
- ... misc fixes and cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
locking/static_keys: Fix non static symbol Sparse warning
locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
locking/atomic, arch/tile: Fix tilepro build
locking/atomic, arch/m68k: Remove comment
locking/atomic, arch/arc: Fix build
locking/Documentation: Clarify limited control-dependency scope
locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
locking/atomic, arch/mips: Convert to _relaxed atomics
locking/atomic, arch/alpha: Convert to _relaxed atomics
locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
locking/atomic: Fix atomic64_relaxed() bits
locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
...
Diffstat (limited to 'arch/xtensa')
-rw-r--r-- | arch/xtensa/include/asm/atomic.h | 52 | ||||
-rw-r--r-- | arch/xtensa/include/asm/spinlock.h | 10 |
2 files changed, 56 insertions, 6 deletions
diff --git a/arch/xtensa/include/asm/atomic.h b/arch/xtensa/include/asm/atomic.h index fd8017ce298a..e7a23f2a519a 100644 --- a/arch/xtensa/include/asm/atomic.h +++ b/arch/xtensa/include/asm/atomic.h @@ -98,6 +98,26 @@ static inline int atomic_##op##_return(int i, atomic_t * v) \ return result; \ } +#define ATOMIC_FETCH_OP(op) \ +static inline int atomic_fetch_##op(int i, atomic_t * v) \ +{ \ + unsigned long tmp; \ + int result; \ + \ + __asm__ __volatile__( \ + "1: l32i %1, %3, 0\n" \ + " wsr %1, scompare1\n" \ + " " #op " %0, %1, %2\n" \ + " s32c1i %0, %3, 0\n" \ + " bne %0, %1, 1b\n" \ + : "=&a" (result), "=&a" (tmp) \ + : "a" (i), "a" (v) \ + : "memory" \ + ); \ + \ + return result; \ +} + #else /* XCHAL_HAVE_S32C1I */ #define ATOMIC_OP(op) \ @@ -138,18 +158,42 @@ static inline int atomic_##op##_return(int i, atomic_t * v) \ return vval; \ } +#define ATOMIC_FETCH_OP(op) \ +static inline int atomic_fetch_##op(int i, atomic_t * v) \ +{ \ + unsigned int tmp, vval; \ + \ + __asm__ __volatile__( \ + " rsil a15,"__stringify(TOPLEVEL)"\n" \ + " l32i %0, %3, 0\n" \ + " " #op " %1, %0, %2\n" \ + " s32i %1, %3, 0\n" \ + " wsr a15, ps\n" \ + " rsync\n" \ + : "=&a" (vval), "=&a" (tmp) \ + : "a" (i), "a" (v) \ + : "a15", "memory" \ + ); \ + \ + return vval; \ +} + #endif /* XCHAL_HAVE_S32C1I */ -#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_OPS(add) ATOMIC_OPS(sub) -ATOMIC_OP(and) -ATOMIC_OP(or) -ATOMIC_OP(xor) +#undef ATOMIC_OPS +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) + +ATOMIC_OPS(and) +ATOMIC_OPS(or) +ATOMIC_OPS(xor) #undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP diff --git a/arch/xtensa/include/asm/spinlock.h b/arch/xtensa/include/asm/spinlock.h index 1d95fa5dcd10..a36221cf6363 100644 --- a/arch/xtensa/include/asm/spinlock.h +++ b/arch/xtensa/include/asm/spinlock.h @@ -11,6 +11,9 @@ #ifndef _XTENSA_SPINLOCK_H #define _XTENSA_SPINLOCK_H +#include <asm/barrier.h> +#include <asm/processor.h> + /* * spinlock * @@ -29,8 +32,11 @@ */ #define arch_spin_is_locked(x) ((x)->slock != 0) -#define arch_spin_unlock_wait(lock) \ - do { while (arch_spin_is_locked(lock)) cpu_relax(); } while (0) + +static inline void arch_spin_unlock_wait(arch_spinlock_t *lock) +{ + smp_cond_load_acquire(&lock->slock, !VAL); +} #define arch_spin_lock_flags(lock, flags) arch_spin_lock(lock) |