Hello Peter,
On (08/30/17 10:47), Peter Zijlstra wrote:
[..]
> On Wed, Aug 30, 2017 at 10:42:07AM +0200, Peter Zijlstra wrote:
> >
> > So the overhead looks to be spread out over all sorts, which makes it
> > harder to find and fix.
> >
> > stack unwinding is done lots and is fairly expensive, I
m; ax...@kernel.dk; linux-
> s...@vger.kernel.org; s...@canb.auug.org.au; linux-n...@vger.kernel.org;
> kernel-t...@lge.com
> Subject: Re: possible circular locking dependency detected [was: linux-
> next: Tree for Aug 22]
>
> On Wed, Aug 30, 2017 at 10:42:07AM +0200, Peter Zijlstra
On Wed, Aug 30, 2017 at 10:42:07AM +0200, Peter Zijlstra wrote:
>
> So the overhead looks to be spread out over all sorts, which makes it
> harder to find and fix.
>
> stack unwinding is done lots and is fairly expensive, I've not yet
> checked if crossrelease does too much of that.
Aah, we do a
On Wed, Aug 30, 2017 at 03:15:11PM +0900, Sergey Senozhatsky wrote:
> Hi,
>
> On (08/30/17 14:43), Byungchul Park wrote:
> [..]
> > > notably slower than earlier 4.13 linux-next. (e.g. scrolling in vim
> > > is irritatingly slow)
> >
> > To Ingo,
> >
> > I cannot decide if we have to roll back C
Hi,
On (08/30/17 14:43), Byungchul Park wrote:
[..]
> > notably slower than earlier 4.13 linux-next. (e.g. scrolling in vim
> > is irritatingly slow)
>
> To Ingo,
>
> I cannot decide if we have to roll back CONFIG_LOCKDEP_CROSSRELEASE
> dependency on CONFIG_PROVE_LOCKING in Kconfig. With them en
On Wed, Aug 30, 2017 at 02:20:37PM +0900, Sergey Senozhatsky wrote:
> Byungchul, a quick question.
Hello Sergey,
> have you measured the performance impact? somehow my linux-next is
Yeah, it might have performance impact inevitably.
> notably slower than earlier 4.13 linux-next. (e.g. scrolling
On (08/23/17 09:03), Byungchul Park wrote:
[..]
> > Byungchul, did you add the crosslock checks to lockdep? Can you have a look
> > at
> > the above report? That report namely doesn't make sense to me.
>
> The report is talking about the following lockup:
>
> A work in a worker
Hi,
On (08/24/17 12:39), Boqun Feng wrote:
> On Wed, Aug 23, 2017 at 02:55:17PM +0900, Sergey Senozhatsky wrote:
> > On (08/23/17 13:35), Boqun Feng wrote:
> > > > KERN_CONT and "\n" should not be together. "\n" flushes the cont
> > > > buffer immediately.
> > > >
> > >
> > > Hmm.. Not quite fam
On Wed, Aug 23, 2017 at 02:55:17PM +0900, Sergey Senozhatsky wrote:
> On (08/23/17 13:35), Boqun Feng wrote:
> > > KERN_CONT and "\n" should not be together. "\n" flushes the cont
> > > buffer immediately.
> > >
> >
> > Hmm.. Not quite familiar with printk() stuffs, but I could see several
> > us
On Wed, Aug 23, 2017 at 09:03:04AM +0900, Byungchul Park wrote:
> On Tue, Aug 22, 2017 at 09:43:56PM +, Bart Van Assche wrote:
> The report is talking about the following lockup:
>
> A work in a worker A task work on exit to user
> -- --
On (08/23/17 13:35), Boqun Feng wrote:
> > KERN_CONT and "\n" should not be together. "\n" flushes the cont
> > buffer immediately.
> >
>
> Hmm.. Not quite familiar with printk() stuffs, but I could see several
> usages of printk(KERN_CONT "...\n") in kernel.
>
> Did a bit research myself, and I
On (08/23/17 13:35), Boqun Feng wrote:
[..]
> > > printk(KERN_CONT ");\n");
> >
> > KERN_CONT and "\n" should not be together. "\n" flushes the cont
> > buffer immediately.
> >
>
> Hmm.. Not quite familiar with printk() stuffs, but I could see several
> usages of printk(KERN_CONT "...\
On Wed, Aug 23, 2017 at 12:38:13PM +0800, Boqun Feng wrote:
> From: Boqun Feng
> Date: Wed, 23 Aug 2017 12:12:16 +0800
> Subject: [PATCH] lockdep: Print proper scenario if cross deadlock detected at
> acquisition time
>
> For a potential deadlock about CROSSRELEASE as follow:
>
> P1
On Wed, Aug 23, 2017 at 01:46:48PM +0900, Sergey Senozhatsky wrote:
> On (08/23/17 12:38), Boqun Feng wrote:
> [..]
> > diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
> > index 642fb5362507..a3709e15f609 100644
> > --- a/kernel/locking/lockdep.c
> > +++ b/kernel/locking/lockdep.c
On Wed, Aug 23, 2017 at 01:46:17PM +0900, Byungchul Park wrote:
> On Wed, Aug 23, 2017 at 11:49:51AM +0800, Boqun Feng wrote:
> > Hi Byungchul,
> >
> > On Wed, Aug 23, 2017 at 09:03:04AM +0900, Byungchul Park wrote:
> > > On Tue, Aug 22, 2017 at 09:43:56PM +, Bart Van Assche wrote:
> > > > On
On (08/23/17 12:38), Boqun Feng wrote:
[..]
> diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
> index 642fb5362507..a3709e15f609 100644
> --- a/kernel/locking/lockdep.c
> +++ b/kernel/locking/lockdep.c
> @@ -1156,6 +1156,23 @@ print_circular_lock_scenario(struct held_lock *src,
>
On Wed, Aug 23, 2017 at 11:49:51AM +0800, Boqun Feng wrote:
> Hi Byungchul,
>
> On Wed, Aug 23, 2017 at 09:03:04AM +0900, Byungchul Park wrote:
> > On Tue, Aug 22, 2017 at 09:43:56PM +, Bart Van Assche wrote:
> > > On Tue, 2017-08-22 at 19:47 +0900, Sergey Senozhatsky wrote:
> > > > ==
On Wed, Aug 23, 2017 at 11:49:51AM +0800, Boqun Feng wrote:
> Hi Byungchul,
>
> On Wed, Aug 23, 2017 at 09:03:04AM +0900, Byungchul Park wrote:
> > On Tue, Aug 22, 2017 at 09:43:56PM +, Bart Van Assche wrote:
> > > On Tue, 2017-08-22 at 19:47 +0900, Sergey Senozhatsky wrote:
> > > > ==
Hi Byungchul,
On Wed, Aug 23, 2017 at 09:03:04AM +0900, Byungchul Park wrote:
> On Tue, Aug 22, 2017 at 09:43:56PM +, Bart Van Assche wrote:
> > On Tue, 2017-08-22 at 19:47 +0900, Sergey Senozhatsky wrote:
> > > ==
> > > WARNING: possible cir
On Wed, Aug 23, 2017 at 11:36:49AM +0900, Sergey Senozhatsky wrote:
> On (08/23/17 09:03), Byungchul Park wrote:
> [..]
>
> aha, ok
>
> > The report is talking about the following lockup:
> >
> > A work in a worker A task work on exit to user
> > --
On (08/23/17 09:03), Byungchul Park wrote:
[..]
aha, ok
> The report is talking about the following lockup:
>
> A work in a worker A task work on exit to user
> -- ---
> mutex_lock(&bdev->bd_mutex)
>
On Tue, Aug 22, 2017 at 09:43:56PM +, Bart Van Assche wrote:
> On Tue, 2017-08-22 at 19:47 +0900, Sergey Senozhatsky wrote:
> > ==
> > WARNING: possible circular locking dependency detected
> > 4.13.0-rc6-next-20170822-dbg-00020-g39758ed8aae0-
On Tue, 2017-08-22 at 19:47 +0900, Sergey Senozhatsky wrote:
> ==
> WARNING: possible circular locking dependency detected
> 4.13.0-rc6-next-20170822-dbg-00020-g39758ed8aae0-dirty #1746 Not tainted
> ---
23 matches
Mail list logo
