dmapool: speedup DMAPOOL_DEBUG with init_on_alloc

abattersby · akpm00 · commit 290911c56f98 · 2023-05-06T10:33:36.000-07:00
Avoid double-memset of the same allocated memory in dma_pool_alloc() when both DMAPOOL_DEBUG is enabled and init_on_alloc=1. Link: https://lkml.kernel.org/r/20230126215125.4069751-6-kbusch@meta.com Fixes: 2d55c16 ("dmapool: create/destroy cleanup") Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
diff --git a/mm/dmapool.c b/mm/dmapool.c
@@ -356,7 +356,7 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
 			break;
 		}
 	}
-	if (!(mem_flags & __GFP_ZERO))
+	if (!want_init_on_alloc(mem_flags))
 		memset(retval, POOL_POISON_ALLOCATED, pool->size);
 #endif
 	spin_unlock_irqrestore(&pool->lock, flags);

Original file line number	Diff line number	Diff line change
`@@ -356,7 +356,7 @@ void dma_pool_alloc(struct dma_pool pool, gfp_t mem_flags,`
`356`	`356`	`break;`
`357`	`357`	`}`
`358`	`358`	`}`
`359`		`- if (!(mem_flags & __GFP_ZERO))`
	`359`	`+ if (!want_init_on_alloc(mem_flags))`
`360`	`360`	`memset(retval, POOL_POISON_ALLOCATED, pool->size);`
`361`	`361`	`#endif`
`362`	`362`	`spin_unlock_irqrestore(&pool->lock, flags);`