atomic: fix atomic_add_unless() fallback's return value

According to the kernel documentation:
  Returns non-zero if @v was not @u, and zero otherwise.

Fixes: 63fc571863 ("atomic: add atomic_add_unless()")
Closes: https://gitlab.freedesktop.org/mesa/drm/issues/17
Signed-off-by: David Shao <davshao@gmail.com>
Reviewed-by: Eric Engestrom <eric@engestrom.ch>

[Eric: fix its callers to maintain current behaviour]
Signed-off-by: Eric Engestrom <eric@engestrom.ch>
main
Eric Engestrom 2017-03-15 23:27:25 +00:00 committed by Matt Turner
parent cf54ebf6cf
commit 3ff3d59ed9
2 changed files with 21 additions and 19 deletions

View File

@ -1382,22 +1382,23 @@ static void drm_intel_gem_bo_unreference(drm_intel_bo *bo)
assert(atomic_read(&bo_gem->refcount) > 0); assert(atomic_read(&bo_gem->refcount) > 0);
if (atomic_add_unless(&bo_gem->refcount, -1, 1)) { if (atomic_add_unless(&bo_gem->refcount, -1, 1))
drm_intel_bufmgr_gem *bufmgr_gem = return;
(drm_intel_bufmgr_gem *) bo->bufmgr;
struct timespec time;
clock_gettime(CLOCK_MONOTONIC, &time); drm_intel_bufmgr_gem *bufmgr_gem =
(drm_intel_bufmgr_gem *) bo->bufmgr;
struct timespec time;
pthread_mutex_lock(&bufmgr_gem->lock); clock_gettime(CLOCK_MONOTONIC, &time);
if (atomic_dec_and_test(&bo_gem->refcount)) { pthread_mutex_lock(&bufmgr_gem->lock);
drm_intel_gem_bo_unreference_final(bo, time.tv_sec);
drm_intel_gem_cleanup_bo_cache(bufmgr_gem, time.tv_sec);
}
pthread_mutex_unlock(&bufmgr_gem->lock); if (atomic_dec_and_test(&bo_gem->refcount)) {
drm_intel_gem_bo_unreference_final(bo, time.tv_sec);
drm_intel_gem_cleanup_bo_cache(bufmgr_gem, time.tv_sec);
} }
pthread_mutex_unlock(&bufmgr_gem->lock);
} }
static int drm_intel_gem_bo_map(drm_intel_bo *bo, int write_enable) static int drm_intel_gem_bo_map(drm_intel_bo *bo, int write_enable)
@ -3377,16 +3378,17 @@ drm_intel_bufmgr_gem_unref(drm_intel_bufmgr *bufmgr)
{ {
drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *)bufmgr; drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *)bufmgr;
if (atomic_add_unless(&bufmgr_gem->refcount, -1, 1)) { if (atomic_add_unless(&bufmgr_gem->refcount, -1, 1))
pthread_mutex_lock(&bufmgr_list_mutex); return;
if (atomic_dec_and_test(&bufmgr_gem->refcount)) { pthread_mutex_lock(&bufmgr_list_mutex);
DRMLISTDEL(&bufmgr_gem->managers);
drm_intel_bufmgr_gem_destroy(bufmgr);
}
pthread_mutex_unlock(&bufmgr_list_mutex); if (atomic_dec_and_test(&bufmgr_gem->refcount)) {
DRMLISTDEL(&bufmgr_gem->managers);
drm_intel_bufmgr_gem_destroy(bufmgr);
} }
pthread_mutex_unlock(&bufmgr_list_mutex);
} }
drm_public void *drm_intel_gem_bo_map__gtt(drm_intel_bo *bo) drm_public void *drm_intel_gem_bo_map__gtt(drm_intel_bo *bo)

View File

@ -108,7 +108,7 @@ static inline int atomic_add_unless(atomic_t *v, int add, int unless)
c = atomic_read(v); c = atomic_read(v);
while (c != unless && (old = atomic_cmpxchg(v, c, c + add)) != c) while (c != unless && (old = atomic_cmpxchg(v, c, c + add)) != c)
c = old; c = old;
return c == unless; return c != unless;
} }
#endif #endif