Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1211709

Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers

Show all headers | View raw

On Sun, Aug 23, 2015 at 09:01:01AM -0700, Paul E. McKenney wrote:
> The boot CPU is excluded from tick_nohz_full_mask in tick_nohz_init(),
> which is called from tick_init() which is called from start_kernel()
> shortly after rcu_init():
> 
> 	cpu = smp_processor_id();
> 
> 	if (cpumask_test_cpu(cpu, tick_nohz_full_mask)) {
> 		pr_warning("NO_HZ: Clearing %d from nohz_full range for timekeeping\n", cpu);
> 		cpumask_clear_cpu(cpu, tick_nohz_full_mask);
> 	}
> 
> This happens after the call to tick_nohz_init_all() that does the
> cpumask_setall() that you called out above.
> 
> Or is a recent patch that I missed changing this?

Exactly, this happens right after tick_nohz_full_mask is filled and
makes sure that at least the boot CPU runs as a housekeeper. We
also make sure that it can't become offline later.

Thanks.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Ingo Molnar <mingo@kernel.org> - 2015-08-23 07:50 +0200
  Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2015-08-23 18:10 +0200
    Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Frederic Weisbecker <fweisbec@gmail.com> - 2015-08-24 03:30 +0200
    Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Ingo Molnar <mingo@kernel.org> - 2015-08-24 08:50 +0200
      Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to  housekeepers Mike Galbraith <umgwanakikbuti@gmail.com> - 2015-08-24 09:30 +0200
        Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Ingo Molnar <mingo@kernel.org> - 2015-08-24 09:50 +0200
          Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to  housekeepers Mike Galbraith <umgwanakikbuti@gmail.com> - 2015-08-24 10:00 +0200
            Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Ingo Molnar <mingo@kernel.org> - 2015-08-24 10:10 +0200
      Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Frederic Weisbecker <fweisbec@gmail.com> - 2015-08-24 15:40 +0200
        Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to  housekeepers Mike Galbraith <umgwanakikbuti@gmail.com> - 2015-08-24 16:10 +0200
        Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Ingo Molnar <mingo@kernel.org> - 2015-08-25 10:30 +0200
          Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Frederic Weisbecker <fweisbec@gmail.com> - 2015-08-25 15:50 +0200
            Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Ingo Molnar <mingo@kernel.org> - 2015-08-28 10:40 +0200
              Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Frederic Weisbecker <fweisbec@gmail.com> - 2015-08-28 14:40 +0200
      Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2015-08-24 16:00 +0200
        Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Frederic Weisbecker <fweisbec@gmail.com> - 2015-08-24 16:10 +0200
          Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> - 2015-08-24 17:50 +0200
  Re: [PATCH RESEND] sched/nohz: Affine unpinned timers to housekeepers Frederic Weisbecker <fweisbec@gmail.com> - 2015-08-24 03:50 +0200

csiph-web