+ dmapool-speedup-dmapool_debug-with-init_on_alloc.patch added to mm-unstable branch

+ dmapool-speedup-dmapool_debug-with-init_on_alloc.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: dmapool: speedup DMAPOOL_DEBUG with init_on_alloc
has been added to the -mm mm-unstable branch.  Its filename is
     dmapool-speedup-dmapool_debug-with-init_on_alloc.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/dmapool-speedup-dmapool_debug-with-init_on_alloc.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Tony Battersby <tonyb@cybernetics.com>
Subject: dmapool: speedup DMAPOOL_DEBUG with init_on_alloc
Date: Thu, 26 Jan 2023 13:51:18 -0800

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
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>
---

 mm/dmapool.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/dmapool.c~dmapool-speedup-dmapool_debug-with-init_on_alloc
+++ a/mm/dmapool.c
@@ -356,7 +356,7 @@ void *dma_pool_alloc(struct dma_pool *po
 			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);
_

Patches currently in -mm which might be from tonyb@cybernetics.com are

dmapool-remove-checks-for-dev-==-null.patch
dmapool-use-sysfs_emit-instead-of-scnprintf.patch
dmapool-cleanup-integer-types.patch
dmapool-speedup-dmapool_debug-with-init_on_alloc.patch