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MIPS: perf: Mark pmu interupt IRQF_NO_THREAD

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In RT kernel, I ran into the following calltrace, so PMU interrupts cannot
be threaded

in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/0
INFO: lockdep is turned off.
Call Trace:
[<ffffffff8088595c>] dump_stack+0x1c/0x50
[<ffffffff801a958c>] __might_sleep+0x13c/0x148
[<ffffffff80891c54>] rt_spin_lock+0x3c/0xb0
[<ffffffff801ad29c>] __wake_up+0x3c/0x80
[<ffffffff80243ba4>] perf_event_wakeup+0x8c/0xf8
[<ffffffff80243c50>] perf_pending_event+0x40/0x78
[<ffffffff8023d88c>] irq_work_run+0x74/0xc0
[<ffffffff80152640>] mipsxx_pmu_handle_shared_irq+0x110/0x228
[<ffffffff8015276c>] mipsxx_pmu_handle_irq+0x14/0x30
[<ffffffff801ffda4>] handle_irq_event_percpu+0xbc/0x470
[<ffffffff80204478>] handle_percpu_irq+0x98/0xc8
[<ffffffff801ff284>] generic_handle_irq+0x4c/0x68
[<ffffffff8089748c>] do_IRQ+0x2c/0x48
[<ffffffff80105864>] plat_irq_dispatch+0x64/0xd0

[ralf@linux-mips.org: I don't see why based on this register dump the
handler should be marked IRQF_NO_THREAD - but the handler is manipulating
per-CPU resources so we don't want it to be rescheduled to another CPU.]

Signed-off-by: Yang Wei <Wei.Yang@windriver.com>
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Cc: mingo@redhat.com
Cc: acme@kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7506/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Yang Wei 2014-08-05 13:37:47 +08:00 committed by Ralf Baechle
parent 7d1311b93e
commit ec756d45b7
1 changed files with 1 additions and 1 deletions
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2
arch/mips/kernel/perf_event_mipsxx.c
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@ -558,7 +558,7 @@ static int mipspmu_get_irq(void)
if (mipspmu.irq >= 0) {
/* Request my own irq handler. */
err = request_irq(mipspmu.irq, mipsxx_pmu_handle_irq,
IRQF_PERCPU | IRQF_NOBALANCING,
IRQF_PERCPU | IRQF_NOBALANCING | IRQF_NO_THREAD,
"mips_perf_pmu", NULL);
if (err) {
pr_warning("Unable to request IRQ%d for MIPS "