mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set

H. Peter Anvin · H. Peter Anvin · commit a269cca9926f · 2009-08-31T11:17:44.000-07:00
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 &lt;hpa@zytor.com&gt;
LKML-Reference: &lt;4A9828F4.4040905@zytor.com&gt;
Cc: Venkatesh Pallipadi &lt;venkatesh.pallipadi@intel.com&gt;
Cc: Suresh Siddha &lt;suresh.siddha@intel.com&gt;
diff --git 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

Original file line number	Diff line number	Diff line change
`@@ -153,7 +153,7 @@ config MEMORY_HOTREMOVE`
`153`	`153`	`#`
`154`	`154`	`config PAGEFLAGS_EXTENDED`
`155`	`155`	`def_bool y`
`156`		`- depends on 64BIT \|\| SPARSEMEM_VMEMMAP \|\| !NUMA \|\| !SPARSEMEM`
	`156`	`+ depends on 64BIT \|\| SPARSEMEM_VMEMMAP \|\| !SPARSEMEM`
`157`	`157`
`158`	`158`	`# Heavily threaded applications may benefit from splitting the mm-wide`
`159`	`159`	`# page_table_lock, so that faults on different parts of the user address`