A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-30 03:27:44 -04:00
Code Issues Projects Releases Packages Wiki Activity

jbd: use a single printk for jbd_debug()

Browse source 
Backport of jbd2 commit 169f1a2a87
("jbd2: use a single printk for jbd_debug()")

Since the jbd_debug() is implemented with two separate printk()
calls, it can lead to corrupted and misleading debug output like
the following (see lines marked with "*"):

[  290.339362] (fs/jbd2/journal.c, 203): kjournald2: kjournald2 wakes
[  290.339365] (fs/jbd2/journal.c, 155): kjournald2: commit_sequence=42103, commit_request=42104
[  290.339369] (fs/jbd2/journal.c, 158): kjournald2: OK, requests differ
[* 290.339376] (fs/jbd2/journal.c, 648): jbd2_log_wait_commit:
[* 290.339379] (fs/jbd2/commit.c, 370): jbd2_journal_commit_transaction: JBD2: want 42104, j_commit_sequence=42103
[* 290.339382] JBD2: starting commit of transaction 42104
[  290.339410] (fs/jbd2/revoke.c, 566): jbd2_journal_write_revoke_records: Wrote 0 revoke records
[  290.376555] (fs/jbd2/commit.c, 1088): jbd2_journal_commit_transaction: JBD2: commit 42104 complete, head 42079

i.e. the debug output from log_wait_commit and journal_commit_transaction
have become interleaved.  The output should have been:

(fs/jbd2/journal.c, 648): jbd2_log_wait_commit: JBD2: want 42104, j_commit_sequence=42103
(fs/jbd2/commit.c, 370): jbd2_journal_commit_transaction: JBD2: starting commit of transaction 42104

It is expected that this is not easy to replicate -- I was only able
to cause it on preempt-rt kernels, and even then only under heavy
I/O load.

Signed-off-by: Paul Gortmaker <[email protected]>
Signed-off-by: Jan Kara <[email protected]>
This commit is contained in:
Paul Gortmaker 2013-08-01 15:01:08 -04:00 • committed by Jan Kara
commit e99a03c6f5
2 changed files with 24 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

18
fs/jbd/journal.c
View file

@ -90,6 +90,24 @@ static int journal_convert_superblock_v1(journal_t *, journal_superblock_t *);
static void __journal_abort_soft (journal_t *journal, int errno);
static const char *journal_dev_name(journal_t *journal, char *buffer);
#ifdef CONFIG_JBD_DEBUG
void __jbd_debug(int level, const char *file, const char *func,
unsigned int line, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
if (level > journal_enable_debug)
return;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
printk(KERN_DEBUG "%s: (%s, %u): %pV\n", file, func, line, &vaf);
va_end(args);
}
EXPORT_SYMBOL(__jbd_debug);
#endif
/*
* Helper function used to manage commit timeouts
*/