* Jens Axboe <jaxboe@xxxxxxxxxxxx> wrote: > On 2010-06-09 03:53, Linus Torvalds wrote: > >> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=16129 > >> Subject : BUG: using smp_processor_id() in preemptible [00000000] code: jbd2/sda2 > >> Submitter : Jan Kreuzer <kontrollator@xxxxxx> > >> Date : 2010-06-05 06:15 (4 days old) > > > > This seems to have been introduced by > > > > commit 7cbaef9c83e58bbd4bdd534b09052b6c5ec457d5 > > Author: Ingo Molnar <mingo@xxxxxxx> > > Date: Sat Nov 8 17:05:38 2008 +0100 > > > > sched: optimize sched_clock() a bit > > > > sched_clock() uses cycles_2_ns() needlessly - which is an irq-disabling > > variant of __cycles_2_ns(). > > > > Most of the time sched_clock() is called with irqs disabled already. > > The few places that call it with irqs enabled need to be updated. > > > > Signed-off-by: Ingo Molnar <mingo@xxxxxxx> > > > > and this seems to be one of those calling cases that need to be updated. > > > > Ingo? The call trace is: > > > > BUG: using smp_processor_id() in preemptible [00000000] code: jbd2/sda2-8/337 > > caller is native_sched_clock+0x3c/0x68 > > Pid: 337, comm: jbd2/sda2-8 Not tainted 2.6.35-rc1jan+ #4 > > Call Trace: > > [<ffffffff812362c5>] debug_smp_processor_id+0xc9/0xe4 > > [<ffffffff8101059d>] native_sched_clock+0x3c/0x68 > > [<ffffffff8101043d>] sched_clock+0x9/0xd > > [<ffffffff81212d7a>] blk_rq_init+0x97/0xa3 > > [<ffffffff81214d71>] get_request+0x1c4/0x2d0 > > [<ffffffff81214ea6>] get_request_wait+0x29/0x1a6 > > [<ffffffff81215537>] __make_request+0x338/0x45b > > [<ffffffff812147c2>] generic_make_request+0x2bb/0x330 > > [<ffffffff81214909>] submit_bio+0xd2/0xef > > [<ffffffff811413cb>] submit_bh+0xf4/0x116 > > [<ffffffff81144853>] block_write_full_page_endio+0x89/0x96 > > [<ffffffff81144875>] block_write_full_page+0x15/0x17 > > [<ffffffff8119b00a>] ext4_writepage+0x356/0x36b > > [<ffffffff810e1f91>] __writepage+0x1a/0x39 > > [<ffffffff810e32a6>] write_cache_pages+0x20d/0x346 > > [<ffffffff810e3406>] generic_writepages+0x27/0x29 > > [<ffffffff811ca279>] journal_submit_data_buffers+0x110/0x17d > > [<ffffffff811ca986>] jbd2_journal_commit_transaction+0x4cb/0x156d > > [<ffffffff811d0cba>] kjournald2+0x147/0x37a > > > > (from the bugzilla thing) > > This should be fixed by commit 28f4197e which was merged on friday. The scheduler commit adding local_clock() (for .36) is: c676329: sched_clock: Add local_clock() API and improve documentation So once that is upstream the block IO statistics code can use that. Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe kernel-testers" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
