39e3ac2599
This fixes a hang seen in jbd2_journal_release_jbd_inode on a lot of Power 6 systems running with ext4. When we get in the hung state, all I/O to the disk in question gets blocked where we stay indefinitely. Looking at the task list, I can see we are stuck in jbd2_journal_release_jbd_inode waiting on a wake up. I added some debug code to detect this scenario and dump additional data if we were stuck in jbd2_journal_release_jbd_inode for longer than 30 minutes. When it hit, I was able to see that i_flags was 0, suggesting we missed the wake up. This patch changes i_flags to be an unsigned long, uses bit operators to access it, and adds barriers around the accesses. Prior to applying this patch, we were regularly hitting this hang on numerous systems in our test environment. After applying the patch, the hangs no longer occur. Signed-off-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> |
||
|---|---|---|
| .. | ||
| checkpoint.c | ||
| commit.c | ||
| journal.c | ||
| Kconfig | ||
| Makefile | ||
| recovery.c | ||
| revoke.c | ||
| transaction.c | ||