This patch moves 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 <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Marek Szyprowski <[email protected]>
---
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 35e2a853bff9c482d789ab331d79aaee07753a97..004496654aaa543a52fdd6684af5a87ef02ff054 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 *);
--
2.24.0.rc0.303.g954a862665-goog
Thanks,
applied to the dma-mapping tree for 5.5.