diff options
Diffstat (limited to 'drivers/gpu/drm/ttm/ttm_page_alloc.c')
-rw-r--r-- | drivers/gpu/drm/ttm/ttm_page_alloc.c | 37 |
1 files changed, 23 insertions, 14 deletions
diff --git a/drivers/gpu/drm/ttm/ttm_page_alloc.c b/drivers/gpu/drm/ttm/ttm_page_alloc.c index 863bef9..76329d2 100644 --- a/drivers/gpu/drm/ttm/ttm_page_alloc.c +++ b/drivers/gpu/drm/ttm/ttm_page_alloc.c @@ -297,9 +297,12 @@ static void ttm_pool_update_free_locked(struct ttm_page_pool *pool, * * @pool: to free the pages from * @free_all: If set to true will free all pages in pool + * @use_static: Safe to use static buffer **/ -static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free) +static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free, + bool use_static) { + static struct page *static_buf[NUM_PAGES_TO_ALLOC]; unsigned long irq_flags; struct page *p; struct page **pages_to_free; @@ -309,8 +312,11 @@ static int ttm_page_pool_free(struct ttm_page_pool *pool, unsigned nr_free) if (NUM_PAGES_TO_ALLOC < nr_free) npages_to_free = NUM_PAGES_TO_ALLOC; - pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), - GFP_KERNEL); + if (use_static) + pages_to_free = static_buf; + else + pages_to_free = kmalloc(npages_to_free * sizeof(struct page *), + GFP_KERNEL); if (!pages_to_free) { pr_err("Failed to allocate memory for pool free operation\n"); return 0; @@ -373,7 +379,8 @@ restart: if (freed_pages) ttm_pages_put(pages_to_free, freed_pages); out: - kfree(pages_to_free); + if (pages_to_free != static_buf) + kfree(pages_to_free); return nr_free; } @@ -382,32 +389,33 @@ out: * * XXX: (dchinner) Deadlock warning! * - * ttm_page_pool_free() does memory allocation using GFP_KERNEL. that means - * this can deadlock when called a sc->gfp_mask that is not equal to - * GFP_KERNEL. - * * This code is crying out for a shrinker per pool.... */ static unsigned long ttm_pool_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) { - static atomic_t start_pool = ATOMIC_INIT(0); + static DEFINE_MUTEX(lock); + static unsigned start_pool; unsigned i; - unsigned pool_offset = atomic_add_return(1, &start_pool); + unsigned pool_offset; struct ttm_page_pool *pool; int shrink_pages = sc->nr_to_scan; unsigned long freed = 0; - pool_offset = pool_offset % NUM_POOLS; + if (!mutex_trylock(&lock)) + return SHRINK_STOP; + pool_offset = ++start_pool % NUM_POOLS; /* select start pool in round robin fashion */ for (i = 0; i < NUM_POOLS; ++i) { unsigned nr_free = shrink_pages; if (shrink_pages == 0) break; pool = &_manager->pools[(i + pool_offset)%NUM_POOLS]; - shrink_pages = ttm_page_pool_free(pool, nr_free); + /* OK to use static buffer since global mutex is held. */ + shrink_pages = ttm_page_pool_free(pool, nr_free, true); freed += nr_free - shrink_pages; } + mutex_unlock(&lock); return freed; } @@ -706,7 +714,7 @@ static void ttm_put_pages(struct page **pages, unsigned npages, int flags, } spin_unlock_irqrestore(&pool->lock, irq_flags); if (npages) - ttm_page_pool_free(pool, npages); + ttm_page_pool_free(pool, npages, false); } /* @@ -845,8 +853,9 @@ void ttm_page_alloc_fini(void) pr_info("Finalizing pool allocator\n"); ttm_pool_mm_shrink_fini(_manager); + /* OK to use static buffer since global mutex is no longer used. */ for (i = 0; i < NUM_POOLS; ++i) - ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES); + ttm_page_pool_free(&_manager->pools[i], FREE_ALL_PAGES, true); kobject_put(&_manager->kobj); _manager = NULL; |