Commits
Guoqing Jiang committed 9e1b0211c5d
dlm: recheck kthread_should_stop() before schedule() Call schedule() here could make the thread miss wake up from kthread_stop(), so it is better to recheck kthread_should_stop() before call schedule(), a symptom happened when I run indefinite test (which mostly created clustered raid1, assemble it in other nodes, then stop them) of clustered raid. $ ps aux|grep md|grep D root 4211 0.0 0.0 19760 2220 ? Ds 02:58 0:00 mdadm -Ssq $ cat /proc/4211/stack kthread_stop+0x4d/0x150 dlm_recoverd_stop+0x15/0x20 [dlm] dlm_release_lockspace+0x2ab/0x460 [dlm] leave+0xbf/0x150 [md_cluster] md_cluster_stop+0x18/0x30 [md_mod] bitmap_free+0x12e/0x140 [md_mod] bitmap_destroy+0x7f/0x90 [md_mod] __md_stop+0x21/0xa0 [md_mod] do_md_stop+0x15f/0x5c0 [md_mod] md_ioctl+0xa65/0x18a0 [md_mod] blkdev_ioctl+0x49e/0x8d0 block_ioctl+0x41/0x50 do_vfs_ioctl+0x96/0x5b0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x1e/0xad This maybe not resolve the issue completely since the KTHREAD_SHOULD_STOP flag could be set between "break" and "schedule", but at least the chance for the symptom happen could be reduce a lot (The indefinite test runs more than 20 hours without problem and it happens easily without the change). Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: David Teigland <teigland@redhat.com>