https://github.com/torvalds/linux
Revision 7b2b55da1db10a5525460633ae4b6fb0be060c41 authored by Jason Xing on 25 August 2019, 00:54:53 UTC, committed by Linus Torvalds on 25 August 2019, 02:48:42 UTC
Only when calling the poll syscall the first time can user receive POLLPRI correctly. After that, user always fails to acquire the event signal. Reproduce case: 1. Get the monitor code in Documentation/accounting/psi.txt 2. Run it, and wait for the event triggered. 3. Kill and restart the process. The question is why we can end up with poll_scheduled = 1 but the work not running (which would reset it to 0). And the answer is because the scheduling side sees group->poll_kworker under RCU protection and then schedules it, but here we cancel the work and destroy the worker. The cancel needs to pair with resetting the poll_scheduled flag. Link: http://lkml.kernel.org/r/1566357985-97781-1-git-send-email-joseph.qi@linux.alibaba.com Signed-off-by: Jason Xing <kerneljasonxing@linux.alibaba.com> Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Caspar Zhang <caspar@linux.alibaba.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent bb65f89
Tip revision: 7b2b55da1db10a5525460633ae4b6fb0be060c41 authored by Jason Xing on 25 August 2019, 00:54:53 UTC
psi: get poll_work to run when calling poll syscall next time
psi: get poll_work to run when calling poll syscall next time
Tip revision: 7b2b55d
| File | Mode | Size |
|---|---|---|
| Kconfig | -rw-r--r-- | 3.2 KB |
| Makefile | -rw-r--r-- | 701 bytes |
| README | -rw-r--r-- | 7.9 KB |
| acl.h | -rw-r--r-- | 1.8 KB |
| bitmap.c | -rw-r--r-- | 39.6 KB |
| dir.c | -rw-r--r-- | 9.0 KB |
| do_balan.c | -rw-r--r-- | 54.3 KB |
| file.c | -rw-r--r-- | 7.5 KB |
| fix_node.c | -rw-r--r-- | 77.4 KB |
| hashes.c | -rw-r--r-- | 3.5 KB |
| ibalance.c | -rw-r--r-- | 34.3 KB |
| inode.c | -rw-r--r-- | 92.3 KB |
| ioctl.c | -rw-r--r-- | 5.3 KB |
| item_ops.c | -rw-r--r-- | 18.1 KB |
| journal.c | -rw-r--r-- | 120.4 KB |
| lbalance.c | -rw-r--r-- | 41.3 KB |
| lock.c | -rw-r--r-- | 2.6 KB |
| namei.c | -rw-r--r-- | 43.8 KB |
| objectid.c | -rw-r--r-- | 6.8 KB |
| prints.c | -rw-r--r-- | 21.4 KB |
| procfs.c | -rw-r--r-- | 13.2 KB |
| reiserfs.h | -rw-r--r-- | 116.6 KB |
| resize.c | -rw-r--r-- | 6.3 KB |
| stree.c | -rw-r--r-- | 64.0 KB |
| super.c | -rw-r--r-- | 69.8 KB |
| tail_conversion.c | -rw-r--r-- | 9.2 KB |
| xattr.c | -rw-r--r-- | 24.8 KB |
| xattr.h | -rw-r--r-- | 3.7 KB |
| xattr_acl.c | -rw-r--r-- | 9.6 KB |
| xattr_security.c | -rw-r--r-- | 2.7 KB |
| xattr_trusted.c | -rw-r--r-- | 1.2 KB |
| xattr_user.c | -rw-r--r-- | 1.1 KB |
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