From: Paul Jackson Mark cpuset global 'number_of_cpusets' as __read_mostly. This global is accessed everytime a zone is considered in the zonelist loops beneath __alloc_pages, looking for a free memory page. If number_of_cpusets is just one, then we can short circuit the mems_allowed check. Since this global is read alot on a hot path, and written rarely, it is an excellent candidate for __read_mostly. Thanks to Christoph Lameter for the suggestion. Signed-off-by: Paul Jackson Signed-off-by: Andrew Morton --- kernel/cpuset.c | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff -puN kernel/cpuset.c~cpuset-mark-number_of_cpusets-read_mostly kernel/cpuset.c --- devel/kernel/cpuset.c~cpuset-mark-number_of_cpusets-read_mostly 2005-12-14 02:48:42.000000000 -0800 +++ devel-akpm/kernel/cpuset.c 2005-12-14 02:48:42.000000000 -0800 @@ -62,7 +62,7 @@ * When there is only one cpuset (the root cpuset) we can * short circuit some hooks. */ -int number_of_cpusets; +int number_of_cpusets __read_mostly; /* See "Frequency meter" comments, below. */ _