[tip:x86/pat] mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set

From: tip-bot for H. Peter Anvin
Date: Mon Aug 31 2009 - 14:25:15 EST


Commit-ID: a269cca9926faf8e44b340b017be0d884203141b
Gitweb: http://git.kernel.org/tip/a269cca9926faf8e44b340b017be0d884203141b
Author: H. Peter Anvin <hpa@xxxxxxxxx>
AuthorDate: Mon, 31 Aug 2009 11:17:44 -0700
Committer: H. Peter Anvin <hpa@xxxxxxxxx>
CommitDate: Mon, 31 Aug 2009 11:17:44 -0700

mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set

CONFIG_PAGEFLAGS_EXTENDED disables a trick to conserve pageflags.
This trick is indended to be enabled when the pressure on page flags
is very high.

The previous condition was:

- depends on 64BIT || SPARSEMEM_VMEMMAP || !NUMA || !SPARSEMEM

... however, the sparsemem code already has a way to crowd out the
node number from the pageflags, which means that !NUMA actually
doesn't contribute to hard pageflags exhaustion.

This is required for the new PG_uncached flag to not cause pageflags
exhaustion on x86_32 + PAE + SPARSEMEM + !NUMA.

Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxx>
LKML-Reference: <4A9828F4.4040905@xxxxxxxxx>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
Cc: Suresh Siddha <suresh.siddha@xxxxxxxxx>


---
mm/Kconfig | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/mm/Kconfig b/mm/Kconfig
index c948d4c..fe221c7 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -153,7 +153,7 @@ config MEMORY_HOTREMOVE
#
config PAGEFLAGS_EXTENDED
def_bool y
- depends on 64BIT || SPARSEMEM_VMEMMAP || !NUMA || !SPARSEMEM
+ depends on 64BIT || SPARSEMEM_VMEMMAP || !SPARSEMEM

# Heavily threaded applications may benefit from splitting the mm-wide
# page_table_lock, so that faults on different parts of the user address
--
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