Re: [PATCH] mm: cma: fix alignment requirements for contiguous regions
From: Michal Nazarewicz <hidden>
Date: 2012-08-24 16:46:49
Also in:
lkml
Marek Szyprowski [off-list ref] writes:
Contiguous Memory Allocator requires each of its regions to be aligned in such a way that it is possible to change migration type for all pageblocks holding it and then isolate page of largest possible order from the buddy allocator (which is MAX_ORDER-1). This patch relaxes alignment requirements by one order, because MAX_ORDER alignment is not really needed. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> CC: Michal Nazarewicz <redacted>
Acked-by: Michal Nazarewicz <redacted>
quoted hunk ↗ jump to hunk
--- drivers/base/dma-contiguous.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 78efb03..34d94c7 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c@@ -250,7 +250,7 @@ int __init dma_declare_contiguous(struct device *dev, unsigned long size, return -EINVAL; /* Sanitise input arguments */ - alignment = PAGE_SIZE << max(MAX_ORDER, pageblock_order); + alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); base = ALIGN(base, alignment); size = ALIGN(size, alignment); limit &= ~(alignment - 1);
-- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +----<email/xmpp: mpn@google.com>--------------ooO--(_)--Ooo--