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Commit 971ada0f authored by Lee Schermerhorn's avatar Lee Schermerhorn Committed by Linus Torvalds
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mempolicy: document cpuset interaction with tmpfs mpol mount option 



Update Documentation/filesystems/tmpfs.txt to describe the interaction of
tmpfs mount option memory policy with tasks' cpuset mems_allowed.

Note: the mount(8) man page [in the util-linux-ng package] requires
similiar updates.

Signed-off-by: default avatarLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 15d77835

Documentation/filesystems/tmpfs.txt

+9 −1
Original line number Diff line number Diff line
@@ -94,11 +94,19 @@ NodeList format is a comma-separated list of decimal numbers and ranges, 
a range being two hyphen-separated decimal numbers, the smallest and

largest node numbers in the range.  For example, mpol=bind:0-3,5,7,9-15



A memory policy with a valid NodeList will be saved, as specified, for

use at file creation time.  When a task allocates a file in the file

system, the mount option memory policy will be applied with a NodeList,

if any, modified by the calling task's cpuset constraints

[See Documentation/cgroups/cpusets.txt] and any optional flags, listed

below.  If the resulting NodeLists is the empty set, the effective memory

policy for the file will revert to "default" policy.



NUMA memory allocation policies have optional flags that can be used in

conjunction with their modes.  These optional flags can be specified

when tmpfs is mounted by appending them to the mode before the NodeList.

See Documentation/vm/numa_memory_policy.txt for a list of all available

memory allocation policy mode flags.

memory allocation policy mode flags and their effect on memory policy.



	=static		is equivalent to	MPOL_F_STATIC_NODES

	=relative	is equivalent to	MPOL_F_RELATIVE_NODES