* [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related)
@ 2010-05-22 21:36 Rafael J. Wysocki
2010-05-22 20:30 ` Andrew Morton
0 siblings, 1 reply; 6+ messages in thread
From: Rafael J. Wysocki @ 2010-05-22 21:36 UTC (permalink / raw)
To: LKML; +Cc: Al Viro, Linus Torvalds, Andrew Morton, Eric Paris
Hi,
I get this every time on boot with current -git:
[ 6.906133] EXT4-fs (sda7): mounted filesystem with ordered data mode
[ 7.014359] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
[ 7.020570] caller is dqstats_inc+0x19/0x2c
[ 7.026658] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
[ 7.032792] Call Trace:
[ 7.038859] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
[ 7.045025] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
[ 7.051201] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
[ 7.057349] [<ffffffff810eccfa>] ? __shrink_dcache_sb+0x284/0x293
[ 7.063574] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
[ 7.069730] [<ffffffff810fc552>] sync_filesystem+0x36/0x4c
[ 7.075867] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
[ 7.081960] [<ffffffff810f4359>] do_mount+0x251/0x78a
[ 7.088039] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
[ 7.094086] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
[ 7.100085] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
[ 7.124208] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
[ 7.130307] caller is dqstats_inc+0x19/0x2c
[ 7.136386] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
[ 7.142512] Call Trace:
[ 7.148629] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
[ 7.154846] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
[ 7.161019] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
[ 7.167171] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
[ 7.173364] [<ffffffff810fc563>] sync_filesystem+0x47/0x4c
[ 7.179522] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
[ 7.185616] [<ffffffff810f4359>] do_mount+0x251/0x78a
[ 7.191663] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
[ 7.197626] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
[ 7.203493] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
[ 11.643596] udev: starting version 153
This is after reverting commit a7cf4145b (anon_inode: set S_IFREG on the
anon_inode) that the system is not really useable with.
Thanks,
Rafael
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related)
2010-05-22 21:36 [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related) Rafael J. Wysocki
@ 2010-05-22 20:30 ` Andrew Morton
2010-05-23 13:21 ` Rafael J. Wysocki
2010-05-24 14:00 ` Jan Kara
0 siblings, 2 replies; 6+ messages in thread
From: Andrew Morton @ 2010-05-22 20:30 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: LKML, Al Viro, Linus Torvalds, Eric Paris, Dmitry Monakhov,
Jan Kara
On Sat, 22 May 2010 23:36:59 +0200 "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
> Hi,
>
> I get this every time on boot with current -git:
>
> [ 6.906133] EXT4-fs (sda7): mounted filesystem with ordered data mode
> [ 7.014359] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
> [ 7.020570] caller is dqstats_inc+0x19/0x2c
> [ 7.026658] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
> [ 7.032792] Call Trace:
> [ 7.038859] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
> [ 7.045025] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
> [ 7.051201] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
> [ 7.057349] [<ffffffff810eccfa>] ? __shrink_dcache_sb+0x284/0x293
> [ 7.063574] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
> [ 7.069730] [<ffffffff810fc552>] sync_filesystem+0x36/0x4c
> [ 7.075867] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
> [ 7.081960] [<ffffffff810f4359>] do_mount+0x251/0x78a
> [ 7.088039] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
> [ 7.094086] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
> [ 7.100085] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
> [ 7.124208] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
> [ 7.130307] caller is dqstats_inc+0x19/0x2c
> [ 7.136386] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
> [ 7.142512] Call Trace:
> [ 7.148629] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
> [ 7.154846] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
> [ 7.161019] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
> [ 7.167171] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
> [ 7.173364] [<ffffffff810fc563>] sync_filesystem+0x47/0x4c
> [ 7.179522] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
> [ 7.185616] [<ffffffff810f4359>] do_mount+0x251/0x78a
> [ 7.191663] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
> [ 7.197626] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
> [ 7.203493] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
> [ 11.643596] udev: starting version 153
>
> This is after reverting commit a7cf4145b (anon_inode: set S_IFREG on the
> anon_inode) that the system is not really useable with.
Caused by "quota: Make quota stat accounting lockless".
Guys, the code this patch adds utterly duplicates the interface
provided by include/linux/percpu_counter.h, only the quota code does it
wrongly and badly. Please, can we use the nice library code?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related)
2010-05-22 20:30 ` Andrew Morton
@ 2010-05-23 13:21 ` Rafael J. Wysocki
2010-05-24 14:00 ` Jan Kara
1 sibling, 0 replies; 6+ messages in thread
From: Rafael J. Wysocki @ 2010-05-23 13:21 UTC (permalink / raw)
To: Andrew Morton
Cc: LKML, Al Viro, Linus Torvalds, Eric Paris, Dmitry Monakhov,
Jan Kara
On Saturday 22 May 2010, Andrew Morton wrote:
> On Sat, 22 May 2010 23:36:59 +0200 "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
>
> > Hi,
> >
> > I get this every time on boot with current -git:
> >
> > [ 6.906133] EXT4-fs (sda7): mounted filesystem with ordered data mode
> > [ 7.014359] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
> > [ 7.020570] caller is dqstats_inc+0x19/0x2c
> > [ 7.026658] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
> > [ 7.032792] Call Trace:
> > [ 7.038859] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
> > [ 7.045025] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
> > [ 7.051201] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
> > [ 7.057349] [<ffffffff810eccfa>] ? __shrink_dcache_sb+0x284/0x293
> > [ 7.063574] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
> > [ 7.069730] [<ffffffff810fc552>] sync_filesystem+0x36/0x4c
> > [ 7.075867] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
> > [ 7.081960] [<ffffffff810f4359>] do_mount+0x251/0x78a
> > [ 7.088039] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
> > [ 7.094086] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
> > [ 7.100085] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
> > [ 7.124208] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
> > [ 7.130307] caller is dqstats_inc+0x19/0x2c
> > [ 7.136386] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
> > [ 7.142512] Call Trace:
> > [ 7.148629] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
> > [ 7.154846] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
> > [ 7.161019] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
> > [ 7.167171] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
> > [ 7.173364] [<ffffffff810fc563>] sync_filesystem+0x47/0x4c
> > [ 7.179522] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
> > [ 7.185616] [<ffffffff810f4359>] do_mount+0x251/0x78a
> > [ 7.191663] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
> > [ 7.197626] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
> > [ 7.203493] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
> > [ 11.643596] udev: starting version 153
> >
> > This is after reverting commit a7cf4145b (anon_inode: set S_IFREG on the
> > anon_inode) that the system is not really useable with.
>
> Caused by "quota: Make quota stat accounting lockless".
FWIW, reverting that commit fixes the issue.
Thanks,
Rafael
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related)
2010-05-22 20:30 ` Andrew Morton
2010-05-23 13:21 ` Rafael J. Wysocki
@ 2010-05-24 14:00 ` Jan Kara
2010-05-24 14:18 ` Dmitry Monakhov
1 sibling, 1 reply; 6+ messages in thread
From: Jan Kara @ 2010-05-24 14:00 UTC (permalink / raw)
To: Andrew Morton
Cc: Rafael J. Wysocki, LKML, Al Viro, Linus Torvalds, Eric Paris,
Dmitry Monakhov, Jan Kara
Hi,
> On Sat, 22 May 2010 23:36:59 +0200 "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
> > [ 6.906133] EXT4-fs (sda7): mounted filesystem with ordered data mode
> > [ 7.014359] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
> > [ 7.020570] caller is dqstats_inc+0x19/0x2c
> > [ 7.026658] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
> > [ 7.032792] Call Trace:
> > [ 7.038859] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
> > [ 7.045025] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
> > [ 7.051201] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
> > [ 7.057349] [<ffffffff810eccfa>] ? __shrink_dcache_sb+0x284/0x293
> > [ 7.063574] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
> > [ 7.069730] [<ffffffff810fc552>] sync_filesystem+0x36/0x4c
> > [ 7.075867] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
> > [ 7.081960] [<ffffffff810f4359>] do_mount+0x251/0x78a
> > [ 7.088039] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
> > [ 7.094086] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
> > [ 7.100085] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
> > [ 7.124208] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
> > [ 7.130307] caller is dqstats_inc+0x19/0x2c
> > [ 7.136386] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
> > [ 7.142512] Call Trace:
> > [ 7.148629] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
> > [ 7.154846] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
> > [ 7.161019] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
> > [ 7.167171] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
> > [ 7.173364] [<ffffffff810fc563>] sync_filesystem+0x47/0x4c
> > [ 7.179522] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
> > [ 7.185616] [<ffffffff810f4359>] do_mount+0x251/0x78a
> > [ 7.191663] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
> > [ 7.197626] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
> > [ 7.203493] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
> > [ 11.643596] udev: starting version 153
> >
> > This is after reverting commit a7cf4145b (anon_inode: set S_IFREG on the
> > anon_inode) that the system is not really useable with.
>
> Caused by "quota: Make quota stat accounting lockless".
>
> Guys, the code this patch adds utterly duplicates the interface
> provided by include/linux/percpu_counter.h, only the quota code does it
> wrongly and badly. Please, can we use the nice library code?
I was thinking about this when merging the code and I thought that I'll save
some memory (~200 bytes) because stats are fine with 32-bit counters (instead of
64-bit ones) and I'm interested only in rough counts, not exact ones. Since the
code Dmitry added was quite simple, I thought the duplication won't be so bad.
But the code is probably more subtle than I thought so those 200 bytes aren't
worth it. So let's convert it to generic per-cpu counters. Dmitry, will you do it?
Hmm, I'm also wondering why I didn't see the warning Rafael was hitting in my
test runs... Ah, my kernel config has CONFIG_PREEMPT_NONE! I guess using
CONFIG_PREEMPT is likely to give a better test coverage, right?
Honza
--
Jan Kara <jack@suse.cz>
SuSE CR Labs
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related)
2010-05-24 14:00 ` Jan Kara
@ 2010-05-24 14:18 ` Dmitry Monakhov
0 siblings, 0 replies; 6+ messages in thread
From: Dmitry Monakhov @ 2010-05-24 14:18 UTC (permalink / raw)
To: Jan Kara
Cc: Andrew Morton, Rafael J. Wysocki, LKML, Al Viro, Linus Torvalds,
Eric Paris, Jan Kara
Jan Kara <jack@suse.cz> writes:
> Hi,
>
>> On Sat, 22 May 2010 23:36:59 +0200 "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
>> > [ 6.906133] EXT4-fs (sda7): mounted filesystem with ordered data mode
>> > [ 7.014359] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
>> > [ 7.020570] caller is dqstats_inc+0x19/0x2c
>> > [ 7.026658] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
>> > [ 7.032792] Call Trace:
>> > [ 7.038859] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
>> > [ 7.045025] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
>> > [ 7.051201] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
>> > [ 7.057349] [<ffffffff810eccfa>] ? __shrink_dcache_sb+0x284/0x293
>> > [ 7.063574] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
>> > [ 7.069730] [<ffffffff810fc552>] sync_filesystem+0x36/0x4c
>> > [ 7.075867] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
>> > [ 7.081960] [<ffffffff810f4359>] do_mount+0x251/0x78a
>> > [ 7.088039] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
>> > [ 7.094086] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
>> > [ 7.100085] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
>> > [ 7.124208] BUG: using smp_processor_id() in preemptible [00000000] code: mount/1501
>> > [ 7.130307] caller is dqstats_inc+0x19/0x2c
>> > [ 7.136386] Pid: 1501, comm: mount Not tainted 2.6.34-tst #25
>> > [ 7.142512] Call Trace:
>> > [ 7.148629] [<ffffffff8117c12b>] debug_smp_processor_id+0xcb/0xdc
>> > [ 7.154846] [<ffffffff8111dfb5>] dqstats_inc+0x19/0x2c
>> > [ 7.161019] [<ffffffff81120fac>] vfs_quota_sync+0x144/0x210
>> > [ 7.167171] [<ffffffff810fc48d>] __sync_filesystem+0x3a/0x7e
>> > [ 7.173364] [<ffffffff810fc563>] sync_filesystem+0x47/0x4c
>> > [ 7.179522] [<ffffffff810deef0>] do_remount_sb+0x65/0x13c
>> > [ 7.185616] [<ffffffff810f4359>] do_mount+0x251/0x78a
>> > [ 7.191663] [<ffffffff810f2c3e>] ? copy_mount_options+0xda/0x146
>> > [ 7.197626] [<ffffffff810f4911>] sys_mount+0x7f/0xb8
>> > [ 7.203493] [<ffffffff81002aeb>] system_call_fastpath+0x16/0x1b
>> > [ 11.643596] udev: starting version 153
>> >
>> > This is after reverting commit a7cf4145b (anon_inode: set S_IFREG on the
>> > anon_inode) that the system is not really useable with.
>>
>> Caused by "quota: Make quota stat accounting lockless".
>>
>> Guys, the code this patch adds utterly duplicates the interface
>> provided by include/linux/percpu_counter.h, only the quota code does it
>> wrongly and badly. Please, can we use the nice library code?
> I was thinking about this when merging the code and I thought that I'll save
> some memory (~200 bytes) because stats are fine with 32-bit counters (instead of
> 64-bit ones) and I'm interested only in rough counts, not exact ones. Since the
> code Dmitry added was quite simple, I thought the duplication won't be so bad.
> But the code is probably more subtle than I thought so those 200 bytes aren't
> worth it. So let's convert it to generic per-cpu counters. Dmitry, will you do it?
Yes. I will.
BTW we are working on generic scalable resource counter which is
based on percpu counters and lockless on fast-paths.
Resource counter examples: quota limits, bean-counters, etc.
The core idea in most situations resource has three main points:
zero, soft-barrier, hard-barrier where exact accuracy is required.
> Hmm, I'm also wondering why I didn't see the warning Rafael was hitting in my
> test runs... Ah, my kernel config has CONFIG_PREEMPT_NONE! I guess using
> CONFIG_PREEMPT is likely to give a better test coverage, right?
Unfortunately preempt_debug was disabled on my testing hosts too.
>
> Honza
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related)
@ 2010-05-29 16:46 Sedat Dilek
0 siblings, 0 replies; 6+ messages in thread
From: Sedat Dilek @ 2010-05-29 16:46 UTC (permalink / raw)
To: LKML; +Cc: Rafael J. Wysocki, Andrew Morton, Jan Kara, dmonakhov
Regression should be fixed by (see pull-request in [1]):
commit f32764bd2bbb6ea003c158b1d276b4dc9f900348
"quota: Convert quota statistics to generic percpu_counter"
The patch is still pending in linux-fs-2.6/for_linus GIT tree and it's
not accepted in upstream, yet.
- Sedat -
[1] http://lkml.org/lkml/2010/5/27/499
[2] http://git.kernel.org/?p=linux/kernel/git/jack/linux-fs-2.6.git;a=commit;h=f32764bd2bbb6ea003c158b1d276b4dc9f900348
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-05-29 16:47 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-05-22 21:36 [git head f4b87dee9] BUG: using smp_processor_id() in preemptible (VFS-related) Rafael J. Wysocki
2010-05-22 20:30 ` Andrew Morton
2010-05-23 13:21 ` Rafael J. Wysocki
2010-05-24 14:00 ` Jan Kara
2010-05-24 14:18 ` Dmitry Monakhov
-- strict thread matches above, loose matches on Subject: below --
2010-05-29 16:46 Sedat Dilek
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox