diff options
Diffstat (limited to 'net/core/page_pool.c')
| -rw-r--r-- | net/core/page_pool.c | 50 |
1 files changed, 40 insertions, 10 deletions
diff --git a/net/core/page_pool.c b/net/core/page_pool.c index dd364d738c00..8bcc7014a61a 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -5,6 +5,7 @@ * Copyright (C) 2016 Red Hat, Inc. */ +#include <linux/error-injection.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/slab.h> @@ -123,9 +124,9 @@ int page_pool_ethtool_stats_get_count(void) } EXPORT_SYMBOL(page_pool_ethtool_stats_get_count); -u64 *page_pool_ethtool_stats_get(u64 *data, void *stats) +u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats) { - struct page_pool_stats *pool_stats = stats; + const struct page_pool_stats *pool_stats = stats; *data++ = pool_stats->alloc_stats.fast; *data++ = pool_stats->alloc_stats.slow; @@ -383,8 +384,8 @@ static struct page *__page_pool_get_cached(struct page_pool *pool) return page; } -static void page_pool_dma_sync_for_device(struct page_pool *pool, - struct page *page, +static void page_pool_dma_sync_for_device(const struct page_pool *pool, + const struct page *page, unsigned int dma_sync_size) { dma_addr_t dma_addr = page_pool_get_dma_addr(page); @@ -550,6 +551,7 @@ struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp) return page; } EXPORT_SYMBOL(page_pool_alloc_pages); +ALLOW_ERROR_INJECTION(page_pool_alloc_pages, NULL); /* Calculate distance between two u32 values, valid if distance is below 2^(31) * https://en.wikipedia.org/wiki/Serial_number_arithmetic#General_Solution @@ -690,8 +692,7 @@ __page_pool_put_page(struct page_pool *pool, struct page *page, page_pool_dma_sync_for_device(pool, page, dma_sync_size); - if (allow_direct && in_softirq() && - page_pool_recycle_in_cache(page, pool)) + if (allow_direct && page_pool_recycle_in_cache(page, pool)) return NULL; /* Page found as candidate for recycling */ @@ -716,9 +717,35 @@ __page_pool_put_page(struct page_pool *pool, struct page *page, return NULL; } +static bool page_pool_napi_local(const struct page_pool *pool) +{ + const struct napi_struct *napi; + u32 cpuid; + + if (unlikely(!in_softirq())) + return false; + + /* Allow direct recycle if we have reasons to believe that we are + * in the same context as the consumer would run, so there's + * no possible race. + * __page_pool_put_page() makes sure we're not in hardirq context + * and interrupts are enabled prior to accessing the cache. + */ + cpuid = smp_processor_id(); + if (READ_ONCE(pool->cpuid) == cpuid) + return true; + + napi = READ_ONCE(pool->p.napi); + + return napi && READ_ONCE(napi->list_owner) == cpuid; +} + void page_pool_put_unrefed_page(struct page_pool *pool, struct page *page, unsigned int dma_sync_size, bool allow_direct) { + if (!allow_direct) + allow_direct = page_pool_napi_local(pool); + page = __page_pool_put_page(pool, page, dma_sync_size, allow_direct); if (page && !page_pool_recycle_in_ring(pool, page)) { /* Cache full, fallback to free pages */ @@ -747,8 +774,11 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data, int count) { int i, bulk_len = 0; + bool allow_direct; bool in_softirq; + allow_direct = page_pool_napi_local(pool); + for (i = 0; i < count; i++) { struct page *page = virt_to_head_page(data[i]); @@ -756,13 +786,13 @@ void page_pool_put_page_bulk(struct page_pool *pool, void **data, if (!page_pool_is_last_ref(page)) continue; - page = __page_pool_put_page(pool, page, -1, false); + page = __page_pool_put_page(pool, page, -1, allow_direct); /* Approved for bulk recycling in ptr_ring cache */ if (page) data[bulk_len++] = page; } - if (unlikely(!bulk_len)) + if (!bulk_len) return; /* Bulk producer into ptr_ring page_pool cache */ @@ -959,7 +989,7 @@ static void page_pool_release_retry(struct work_struct *wq) } void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *), - struct xdp_mem_info *mem) + const struct xdp_mem_info *mem) { refcount_inc(&pool->user_cnt); pool->disconnect = disconnect; @@ -969,7 +999,7 @@ void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *), static void page_pool_disable_direct_recycling(struct page_pool *pool) { /* Disable direct recycling based on pool->cpuid. - * Paired with READ_ONCE() in napi_pp_put_page(). + * Paired with READ_ONCE() in page_pool_napi_local(). */ WRITE_ONCE(pool->cpuid, -1); |