Re: [PATCH v4 1/2] timers: Don't wake ktimersoftd on every tick

[Haris Okanovic]

Hi Daniel,

I didn't have time to look at it yet, aside from confirming Mike's issue 
reproduces on my machine. It's still on my backlog to investigate.

-- Haris


On 06/19/2018 07:43 AM, Daniel Bristot de Oliveira wrote:
> On 04/12/2018 05:00 PM, Haris Okanovic wrote:
> > Hi Mike,
> >
> > I haven't tested the patch with wireshark until now. My system also
> > hangs shortly after it starts. I'm pretty sure I hit workqueues in my
> > earlier tests via the block driver, but it's clearly not whatever
> > wireshark is using. I'll look at it and try to post a fix. CCing the
> > list to avoid this patch until then.
>
> Hi Haris,
>
> Do we have any update regarding a newer version of this patch?
>
> -- Daniel
>
> > Thanks,
> > Haris
> >
> >
> > On 04/09/2018 11:02 PM, Mike Galbraith wrote:
> > > Hi,
> > >
> > > Are these patches dead, or are you planning another submission?  I ask
> > > because I discovered that with them applied, firing up wireshark hangs
> > > the box 100% repeatably, with wireshark never fully initializing.
> > >
> > > Applying them to an otherwise virgin 4.14.20-rt17 to be sure...
> > >
> > > crash> bt 6016PID: 6016   TASK: ffff95dd68572180  CPU: 2   COMMAND:
> > > "dumpcap"
> > >    #0 [ffffb490094f3bc0] __schedule at ffffffffa56d55b9
> > >    #1 [ffffb490094f3c40] schedule at ffffffffa56d5a03
> > >    #2 [ffffb490094f3c58] schedule_timeout at ffffffffa56d8467
> > >    #3 [ffffb490094f3cd8] wait_for_completion at ffffffffa56d6e34
> > >    #4 [ffffb490094f3d18] __wait_rcu_gp at ffffffffa50e59cd
> > >    #5 [ffffb490094f3d58] synchronize_rcu at ffffffffa50ec14e
> > >    #6 [ffffb490094f3d98] packet_set_ring at ffffffffc0c74da0 [af_packet]
> > >    #7 [ffffb490094f3e50] packet_setsockopt at ffffffffc0c75d23 [af_packet]
> > >    #8 [ffffb490094f3ef8] sys_setsockopt at ffffffffa558a5e2
> > >    #9 [ffffb490094f3f30] do_syscall_64 at ffffffffa5001b05
> > > #10 [ffffb490094f3f50] entry_SYSCALL_64_after_hwframe at ffffffffa5800065
> > >       RIP: 00007f3107a1cfaa  RSP: 00007ffc9745c2e8  RFLAGS: 00000246
> > >       RAX: ffffffffffffffda  RBX: 0000000000000001  RCX: 00007f3107a1cfaa
> > >       RDX: 0000000000000005  RSI: 0000000000000107  RDI: 0000000000000003
> > >       RBP: 000055ae1d8eb470   R8: 000000000000001c   R9: 0000000000000002
> > >       R10: 00007ffc9745c350  R11: 0000000000000246  R12: 00007ffc9745c350
> > >       R13: 0000000000000000  R14: 000055ae1d8eb200  R15: 000055ae1d8eb2d0
> > >       ORIG_RAX: 0000000000000036  CS: 0033  SS: 002b
> > > crash> dmesg
> > > ...
> > > [  483.808197] BUG: workqueue lockup - pool cpus=2 node=0 flags=0x0
> > > nice=0 stuck for 52s!
> > > [  483.808204] Showing busy workqueues and worker pools:
> > > [  483.808206] workqueue events: flags=0x0
> > > [  483.808208]   pwq 4: cpus=2 node=0 flags=0x0 nice=0 active=1/256
> > > [  483.808211]     pending: check_corruption
> > > [  492.695124] sysrq: SysRq : Trigger a crash
> > --
> > To unsubscribe from this list: send the line "unsubscribe
> > linux-rt-users" in
> > the body of a message to majordomo@xxxxxxxxxxxxxxx
> > More majordomo info at  https://urldefense.proofpoint.com/v2/url?u=http-3A__vger.kernel.org_majordomo-2Dinfo.html&d=DwIDbA&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=8Bziuw3IaCGjyrSAphuGwHmVdHcVwza-srUYwL9U_Ms&m=FlO5SC4s2pRHcS-IG9Y02aEEXYqou1_HtmZakuldqlY&s=JJ8LrCcEF4YKcLbUey5JTreyXV0p1sJ1wqic9LQ1PCE&e=