From: Michael Ellerman <michael@ellerman.id.au>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@ozlabs.org
Subject: Re: [PATCH 01/18] powerpc: Make decrementer interrupt robust against offlined CPUs
Date: Thu, 10 Mar 2011 19:01:08 +1100 [thread overview]
Message-ID: <1299744068.6272.186.camel@concordia> (raw)
In-Reply-To: <1299566250-10516-2-git-send-email-benh@kernel.crashing.org>
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On Tue, 2011-03-08 at 17:37 +1100, Benjamin Herrenschmidt wrote:
> With some implementations, it is possible that a timer interrupt
> occurs every few seconds on an offline CPU. In this case, just
> re-arm the decrementer and return immediately
>
> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---
> arch/powerpc/kernel/time.c | 15 +++++++++++----
> 1 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
> index 09d31db..ecebc7c 100644
> --- a/arch/powerpc/kernel/time.c
> +++ b/arch/powerpc/kernel/time.c
> @@ -577,14 +577,21 @@ void timer_interrupt(struct pt_regs * regs)
> struct clock_event_device *evt = &decrementer->event;
> u64 now;
>
> + /* Ensure a positive value is written to the decrementer, or else
> + * some CPUs will continuue to take decrementer exceptions
^
Seeing as you're moving it anyway, and maybe a full-stop.
cheers
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next prev parent reply other threads:[~2011-03-10 8:01 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-08 6:37 [PATCHES] powerpc: Cleanup and fix CPU hotplug Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 01/18] powerpc: Make decrementer interrupt robust against offlined CPUs Benjamin Herrenschmidt
2011-03-10 8:01 ` Michael Ellerman [this message]
2011-03-08 6:37 ` [PATCH 02/18] powerpc/smp: soft-replugged CPUs must go back to start_secondary Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 03/18] powerpc/smp: Fix generic_mach_cpu_die() Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 04/18] powerpc/smp: Remove unused generic_cpu_enable() Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 05/18] powerpc/smp: Remove unused smp_ops->cpu_enable() Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 06/18] powerpc/pmac/smp: Fix 32-bit PowerMac cpu_die Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 07/18] powerpc/pmac/smp: Rename fixup_irqs() to migrate_irqs() and use it on ppc32 Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 08/18] powerpc/pmac/smp: Fixup smp_core99_cpu_disable() and use it on 64-bit Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 09/18] powerpc/pmac/smp: Consolidate 32-bit and 64-bit PowerMac cpu_die in one file Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 10/18] powerpc/pmac/smp: Remove HMT changes for PowerMac offline code Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 11/18] powerpc/pmac/smp: Properly NAP offlined CPU on G5 Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 12/18] powerpc/pmac: Rename cpu_state in therm_pm72 to avoid collision Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 13/18] powerpc/smp: Add a smp_ops->bringup_up() done callback Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 14/18] powerpc/pmac/smp: Fix CPU hotplug crashes on some machines Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 15/18] powerpc/smp: Don't expose per-cpu "cpu_state" array Benjamin Herrenschmidt
2011-03-29 5:37 ` Michael Ellerman
2011-03-29 8:13 ` Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 16/18] powerpc/smp: Create idle threads on demand and properly reset them Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 17/18] powerpc/smp: Increase vdso_data->processorCount, not just decrease it Benjamin Herrenschmidt
2011-03-10 3:41 ` Michael Ellerman
2011-03-10 3:46 ` Benjamin Herrenschmidt
2011-03-08 6:37 ` [PATCH 18/18] powerpc/pmac/smp: Remove no-longer needed preempt workaround Benjamin Herrenschmidt
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