From: Zhang Zhen <zhenzhang.zhang@huawei.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: wangnan0@huawei.com,
Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>,
Linux MM <linux-mm@kvack.org>,
David Rientjes <rientjes@google.com>,
Dave Hansen <dave.hansen@intel.com>
Subject: [PATCH v2] memory-hotplug: remove redundant call of page_to_pfn
Date: Wed, 12 Nov 2014 11:56:02 +0800 [thread overview]
Message-ID: <5462DA52.7040100@huawei.com> (raw)
In-Reply-To: <1415764673-32152-1-git-send-email-zhenzhang.zhang@huawei.com>
This is just a small optimization. The start_pfn can be
obtained directly by phys_index << PFN_SECTION_SHIFT.
So the call of page_to_pfn() is redundant and remove it.
v2:
added the purpose of the patch to the description.
Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
---
drivers/base/memory.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 7c5d871..85be040 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -228,8 +228,8 @@ memory_block_action(unsigned long phys_index, unsigned long action, int online_t
struct page *first_page;
int ret;
- first_page = pfn_to_page(phys_index << PFN_SECTION_SHIFT);
- start_pfn = page_to_pfn(first_page);
+ start_pfn = phys_index << PFN_SECTION_SHIFT;
+ first_page = pfn_to_page(start_pfn);
switch (action) {
case MEM_ONLINE:
--
1.8.1.4
.
--
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parent reply other threads:[~2014-11-12 3:56 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <1415764673-32152-1-git-send-email-zhenzhang.zhang@huawei.com>]
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