From: Tetsuo Handa Date: Sun, 3 Aug 2014 11:00:40 +0000 (+0900) Subject: drm/ttm: Choose a pool to shrink correctly in ttm_dma_pool_shrink_scan(). X-Git-Tag: firefly_0821_release~3679^2~1538 X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=a0fe26d09596ccb84f68603f02c4c78a6394e9f9;p=firefly-linux-kernel-4.4.55.git drm/ttm: Choose a pool to shrink correctly in ttm_dma_pool_shrink_scan(). commit 46c2df68f03a236b30808bba361f10900c88d95e upstream. We can use "unsigned int" instead of "atomic_t" by updating start_pool variable under _manager->lock. This patch will make it possible to avoid skipping when choosing a pool to shrink in round-robin style, after next patch changes mutex_lock(_manager->lock) to !mutex_trylock(_manager->lork). Signed-off-by: Tetsuo Handa Signed-off-by: Dave Airlie Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c index e9f65ad2a0eb..de1a753b1d56 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc_dma.c @@ -1006,9 +1006,9 @@ EXPORT_SYMBOL_GPL(ttm_dma_unpopulate); static int ttm_dma_pool_mm_shrink(struct shrinker *shrink, struct shrink_control *sc) { - static atomic_t start_pool = ATOMIC_INIT(0); + static unsigned start_pool; unsigned idx = 0; - unsigned pool_offset = atomic_add_return(1, &start_pool); + unsigned pool_offset; unsigned shrink_pages = sc->nr_to_scan; struct device_pools *p; @@ -1018,7 +1018,7 @@ static int ttm_dma_pool_mm_shrink(struct shrinker *shrink, mutex_lock(&_manager->lock); if (!_manager->npools) goto out; - pool_offset = pool_offset % _manager->npools; + pool_offset = ++start_pool % _manager->npools; list_for_each_entry(p, &_manager->pools, pools) { unsigned nr_free;