From 7dba339faae991a23c54f7b93a58798c58f8c16f Mon Sep 17 00:00:00 2001 From: Mina Almasry Date: Wed, 11 Dec 2024 21:20:31 +0000 Subject: page_pool: disable sync for cpu for dmabuf memory provider dmabuf dma-addresses should not be dma_sync'd for CPU/device. Typically its the driver responsibility to dma_sync for CPU, but the driver should not dma_sync for CPU if the netmem is actually coming from a dmabuf memory provider. The page_pool already exposes a helper for dma_sync_for_cpu: page_pool_dma_sync_for_cpu. Upgrade this existing helper to handle netmem, and have it skip dma_sync if the memory is from a dmabuf memory provider. Drivers should migrate to using this helper when adding support for netmem. Also minimize the impact on the dma syncing performance for pages. Special case the dma-sync path for pages to not go through the overhead checks for dma-syncing and conversion to netmem. Cc: Alexander Lobakin Cc: Jason Gunthorpe Signed-off-by: Mina Almasry Link: https://patch.msgid.link/20241211212033.1684197-5-almasrymina@google.com Signed-off-by: Jakub Kicinski --- net/core/page_pool.c | 1 + 1 file changed, 1 insertion(+) (limited to 'net/core/page_pool.c') diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 275a7fd209d7..e07ad7315955 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -201,6 +201,7 @@ static int page_pool_init(struct page_pool *pool, memcpy(&pool->slow, ¶ms->slow, sizeof(pool->slow)); pool->cpuid = cpuid; + pool->dma_sync_for_cpu = true; /* Validate only known flags were used */ if (pool->slow.flags & ~PP_FLAG_ALL) -- cgit