From d3694f30732fd2a334b93f087033c5a5836f7aba Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 30 Oct 2019 12:32:04 -0700 Subject: [PATCH] dma-debug: reorder struct dma_debug_entry fields Move all fields used during exact match lookups to the first cache line. This makes debug_dma_mapping_error() and friends about 50% faster. Since it removes two 32bit holes, force a cacheline alignment on struct dma_debug_entry. Signed-off-by: Eric Dumazet Signed-off-by: Christoph Hellwig --- kernel/dma/debug.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 4ad74f5987ea..a5b85dabfb8c 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -54,33 +54,33 @@ enum map_err_types { * struct dma_debug_entry - track a dma_map* or dma_alloc_coherent mapping * @list: node on pre-allocated free_entries list * @dev: 'dev' argument to dma_map_{page|single|sg} or dma_alloc_coherent - * @type: single, page, sg, coherent - * @pfn: page frame of the start address - * @offset: offset of mapping relative to pfn * @size: length of the mapping + * @type: single, page, sg, coherent * @direction: enum dma_data_direction * @sg_call_ents: 'nents' from dma_map_sg * @sg_mapped_ents: 'mapped_ents' from dma_map_sg + * @pfn: page frame of the start address + * @offset: offset of mapping relative to pfn * @map_err_type: track whether dma_mapping_error() was checked * @stacktrace: support backtraces when a violation is detected */ struct dma_debug_entry { struct list_head list; struct device *dev; - int type; - unsigned long pfn; - size_t offset; u64 dev_addr; u64 size; + int type; int direction; int sg_call_ents; int sg_mapped_ents; + unsigned long pfn; + size_t offset; enum map_err_types map_err_type; #ifdef CONFIG_STACKTRACE unsigned int stack_len; unsigned long stack_entries[DMA_DEBUG_STACKTRACE_ENTRIES]; #endif -}; +} ____cacheline_aligned_in_smp; typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *);