From: Vladimir Davydov Date: Mon, 20 Oct 2014 11:50:29 +0000 (+0400) Subject: cpuset: convert callback_mutex to a spinlock X-Git-Tag: omap-for-v3.20/drop-legacy-3517~114^2~8 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8447a0fee974433f7e0035fd30e1edecf00e014f;p=pandora-kernel.git cpuset: convert callback_mutex to a spinlock The callback_mutex is only used to synchronize reads/updates of cpusets' flags and cpu/node masks. These operations should always proceed fast so there's no reason why we can't use a spinlock instead of the mutex. Converting the callback_mutex into a spinlock will let us call cpuset_zone_allowed_softwall from atomic context. This, in turn, makes it possible to simplify the code by merging the hardwall and asoftwall checks into the same function, which is the business of the next patch. Suggested-by: Zefan Li Signed-off-by: Vladimir Davydov Acked-by: Christoph Lameter Acked-by: Zefan Li Signed-off-by: Tejun Heo --- Reading git-diff-tree failed