Blame SOURCES/0001-libnuma-make-numa_police_memory-free-of-race.patch
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From 93867c59b0bb29470873a427dc7f06ebaf305221 Mon Sep 17 00:00:00 2001
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From: Pingfan Liu <piliu@redhat.com>
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Date: Mon, 29 Mar 2021 17:33:06 +0800
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Subject: [PATCH] libnuma: make numa_police_memory() free of race
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When numa_police_memory() read-write to memory, it can risk the race of
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another thread write to the same area.
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Using atomic function to protect the read-write operation
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Signed-off-by: Pingfan Liu <piliu@redhat.com>
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---
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libnuma.c | 6 ++++--
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1 file changed, 4 insertions(+), 2 deletions(-)
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diff --git a/libnuma.c b/libnuma.c
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index f073c50..7b8290c 100644
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--- a/libnuma.c
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+++ b/libnuma.c
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@@ -864,8 +864,10 @@ void numa_police_memory(void *mem, size_t size)
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{
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int pagesize = numa_pagesize_int();
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unsigned long i;
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- for (i = 0; i < size; i += pagesize)
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- ((volatile char*)mem)[i] = ((volatile char*)mem)[i];
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+ char *p = mem;
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+ for (i = 0; i < size; i += pagesize, p += pagesize)
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+ __atomic_and_fetch(p, 0xff, __ATOMIC_RELAXED);
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+
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}
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make_internal_alias(numa_police_memory);
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--
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2.29.2
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