diff options
| author | Jan Kara <[email protected]> | 2011-06-23 22:51:47 +0200 |
|---|---|---|
| committer | Joel Becker <[email protected]> | 2011-07-28 02:07:19 -0700 |
| commit | c7e25e6e0b0486492c5faaf6312b37413642c48e (patch) | |
| tree | c097a213a8eb2ad336fb2ef8046d2e71f0fa1f4a /tools/perf/util/scripting-engines/trace-event-python.c | |
| parent | a11f7e63c59810a81494d4c4b028af707d4c7ca4 (diff) | |
ocfs2: Avoid livelock in ocfs2_readpage()
When someone writes to an inode, readers accessing the same inode via
ocfs2_readpage() just busyloop trying to get ip_alloc_sem because
do_generic_file_read() looks up the page again and retries ->readpage()
when previous attempt failed with AOP_TRUNCATED_PAGE. When there are enough
readers, they can occupy all CPUs and in non-preempt kernel the system is
deadlocked because writer holding ip_alloc_sem is never run to release the
semaphore. Fix the problem by making reader block on ip_alloc_sem to break
the busy loop.
Signed-off-by: Jan Kara <[email protected]>
Signed-off-by: Joel Becker <[email protected]>
Diffstat (limited to 'tools/perf/util/scripting-engines/trace-event-python.c')
0 files changed, 0 insertions, 0 deletions