X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvppinfra%2Flock.h;h=c1f0b87dfc6321307dcb4c5730c7a8814dbddca1;hb=67d09e05d0400c62ae3ee654efbbc8cee5806f4f;hp=4645378360db48d1f0be79cee1039b9d023a3c85;hpb=2f6d7bb93c157b874efb79a2d1583a4c368bf89a;p=vpp.git diff --git a/src/vppinfra/lock.h b/src/vppinfra/lock.h index 4645378360d..c1f0b87dfc6 100644 --- a/src/vppinfra/lock.h +++ b/src/vppinfra/lock.h @@ -17,6 +17,7 @@ #define included_clib_lock_h #include +#include #if __x86_64__ #define CLIB_PAUSE() __builtin_ia32_pause () @@ -42,6 +43,9 @@ do { \ #define CLIB_LOCK_DBG_CLEAR(_p) #endif +#define CLIB_SPINLOCK_IS_LOCKED(_p) (*(_p))->lock +#define CLIB_SPINLOCK_ASSERT_LOCKED(_p) ASSERT(CLIB_SPINLOCK_IS_LOCKED((_p))) + typedef struct { CLIB_CACHE_LINE_ALIGN_MARK (cacheline0); @@ -57,7 +61,7 @@ static inline void clib_spinlock_init (clib_spinlock_t * p) { *p = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES, CLIB_CACHE_LINE_BYTES); - memset ((void *) *p, 0, CLIB_CACHE_LINE_BYTES); + clib_memset ((void *) *p, 0, CLIB_CACHE_LINE_BYTES); } static inline void @@ -73,8 +77,15 @@ clib_spinlock_free (clib_spinlock_t * p) static_always_inline void clib_spinlock_lock (clib_spinlock_t * p) { - while (clib_atomic_test_and_set (&(*p)->lock)) - CLIB_PAUSE (); + u32 free = 0; + while (!clib_atomic_cmp_and_swap_acq_relax_n (&(*p)->lock, &free, 1, 0)) + { + /* atomic load limits number of compare_exchange executions */ + while (clib_atomic_load_relax_n (&(*p)->lock)) + CLIB_PAUSE (); + /* on failure, compare_exchange writes (*p)->lock into free */ + free = 0; + } CLIB_LOCK_DBG (p); } @@ -89,9 +100,8 @@ static_always_inline void clib_spinlock_unlock (clib_spinlock_t * p) { CLIB_LOCK_DBG_CLEAR (p); - /* Make sure all writes are complete before releasing the lock */ - CLIB_MEMORY_BARRIER (); - (*p)->lock = 0; + /* Make sure all reads/writes are complete before releasing the lock */ + clib_atomic_release (&(*p)->lock); } static_always_inline void @@ -122,7 +132,7 @@ always_inline void clib_rwlock_init (clib_rwlock_t * p) { *p = clib_mem_alloc_aligned (CLIB_CACHE_LINE_BYTES, CLIB_CACHE_LINE_BYTES); - memset ((void *) *p, 0, CLIB_CACHE_LINE_BYTES); + clib_memset ((void *) *p, 0, CLIB_CACHE_LINE_BYTES); } always_inline void @@ -147,9 +157,7 @@ clib_rwlock_reader_lock (clib_rwlock_t * p) while (clib_atomic_test_and_set (&(*p)->writer_lock)) CLIB_PAUSE (); } - CLIB_MEMORY_BARRIER (); - (*p)->n_readers_lock = 0; - + clib_atomic_release (&(*p)->n_readers_lock); CLIB_LOCK_DBG (p); } @@ -165,12 +173,9 @@ clib_rwlock_reader_unlock (clib_rwlock_t * p) (*p)->n_readers -= 1; if ((*p)->n_readers == 0) { - CLIB_MEMORY_BARRIER (); - (*p)->writer_lock = 0; + clib_atomic_release (&(*p)->writer_lock); } - - CLIB_MEMORY_BARRIER (); - (*p)->n_readers_lock = 0; + clib_atomic_release (&(*p)->n_readers_lock); } always_inline void @@ -185,8 +190,7 @@ always_inline void clib_rwlock_writer_unlock (clib_rwlock_t * p) { CLIB_LOCK_DBG_CLEAR (p); - CLIB_MEMORY_BARRIER (); - (*p)->writer_lock = 0; + clib_atomic_release (&(*p)->writer_lock); } #endif