forked from Minki/linux
9629d04ae0
The inode_free_security() function just took the superblock's isec_lock before checking and trying to remove the inode security struct from the linked list. In many cases, the list was empty and so the lock taking is wasteful as no useful work is done. On multi-socket systems with a large number of CPUs, there can also be a fair amount of spinlock contention on the isec_lock if many tasks are exiting at the same time. This patch changes the code to check the state of the list first before taking the lock and attempting to dequeue it. The list_del_init() can be called more than once on the same list with no harm as long as they are properly serialized. It should not be possible to have inode_free_security() called concurrently with list_add(). For better safety, however, we use list_empty_careful() here even though it is still not completely safe in case that happens. Signed-off-by: Waiman Long <Waiman.Long@hp.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <pmoore@redhat.com> |
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.. | ||
include | ||
ss | ||
.gitignore | ||
avc.c | ||
exports.c | ||
hooks.c | ||
Kconfig | ||
Makefile | ||
netif.c | ||
netlabel.c | ||
netlink.c | ||
netnode.c | ||
netport.c | ||
nlmsgtab.c | ||
selinuxfs.c | ||
xfrm.c |