From: tip-bot for Thomas Gleixner <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org, namit@vmware.com,
peterz@infradead.org, hpa@zytor.com, tglx@linutronix.de
Subject: [tip:x86/apic] x86/smp: Enhance native_send_call_func_ipi()
Date: Thu, 25 Jul 2019 07:34:08 -0700 [thread overview]
Message-ID: <tip-832df3d47badcbc860aef617105b6bc1c9459304@git.kernel.org> (raw)
In-Reply-To: <20190722105220.768238809@linutronix.de>
Commit-ID: 832df3d47badcbc860aef617105b6bc1c9459304
Gitweb: https://git.kernel.org/tip/832df3d47badcbc860aef617105b6bc1c9459304
Author: Thomas Gleixner <tglx@linutronix.de>
AuthorDate: Mon, 22 Jul 2019 20:47:26 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 25 Jul 2019 16:12:01 +0200
x86/smp: Enhance native_send_call_func_ipi()
Nadav noticed that the cpumask allocations in native_send_call_func_ipi()
are noticeable in microbenchmarks.
Use the new cpumask_or_equal() function to simplify the decision whether
the supplied target CPU mask is either equal to cpu_online_mask or equal to
cpu_online_mask except for the CPU on which the function is invoked.
cpumask_or_equal() or's the target mask and the cpumask of the current CPU
together and compares it to cpu_online_mask.
If the result is false, use the mask based IPI function, otherwise check
whether the current CPU is set in the target mask and invoke either the
send_IPI_all() or the send_IPI_allbutselt() APIC callback.
Make the shorthand decision also depend on the static key which enables
shorthand mode. That allows to remove the extra cpumask comparison with
cpu_callout_mask.
Reported-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105220.768238809@linutronix.de
---
arch/x86/kernel/apic/ipi.c | 24 +++++++++++-------------
1 file changed, 11 insertions(+), 13 deletions(-)
diff --git a/arch/x86/kernel/apic/ipi.c b/arch/x86/kernel/apic/ipi.c
index eaac65bf58f0..117ee2323f59 100644
--- a/arch/x86/kernel/apic/ipi.c
+++ b/arch/x86/kernel/apic/ipi.c
@@ -83,23 +83,21 @@ void native_send_call_func_single_ipi(int cpu)
void native_send_call_func_ipi(const struct cpumask *mask)
{
- cpumask_var_t allbutself;
+ if (static_branch_likely(&apic_use_ipi_shorthand)) {
+ unsigned int cpu = smp_processor_id();
- if (!alloc_cpumask_var(&allbutself, GFP_ATOMIC)) {
- apic->send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
+ if (!cpumask_or_equal(mask, cpumask_of(cpu), cpu_online_mask))
+ goto sendmask;
+
+ if (cpumask_test_cpu(cpu, mask))
+ apic->send_IPI_all(CALL_FUNCTION_VECTOR);
+ else if (num_online_cpus() > 1)
+ apic->send_IPI_allbutself(CALL_FUNCTION_VECTOR);
return;
}
- cpumask_copy(allbutself, cpu_online_mask);
- __cpumask_clear_cpu(smp_processor_id(), allbutself);
-
- if (cpumask_equal(mask, allbutself) &&
- cpumask_equal(cpu_online_mask, cpu_callout_mask))
- apic->send_IPI_allbutself(CALL_FUNCTION_VECTOR);
- else
- apic->send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
-
- free_cpumask_var(allbutself);
+sendmask:
+ apic->send_IPI_mask(mask, CALL_FUNCTION_VECTOR);
}
#endif /* CONFIG_SMP */
next prev parent reply other threads:[~2019-07-25 14:34 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-22 18:47 [patch V3 00/25] x86/apic: Support for IPI shorthands Thomas Gleixner
2019-07-22 18:47 ` [patch V3 01/25] x86/kgbd: Use NMI_VECTOR not APIC_DM_NMI Thomas Gleixner
2019-07-25 14:20 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 02/25] x86/apic: Invoke perf_events_lapic_init() after enabling APIC Thomas Gleixner
2019-07-25 14:21 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 03/25] x86/apic: Soft disable APIC before initializing it Thomas Gleixner
2019-07-25 14:22 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 04/25] x86/apic: Make apic_pending_intr_clear() more robust Thomas Gleixner
2019-07-25 14:22 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 05/25] x86/apic: Move IPI inlines into ipi.c Thomas Gleixner
2019-07-25 14:23 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 06/25] x86/apic: Cleanup the include maze Thomas Gleixner
2019-07-25 14:24 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 07/25] x86/apic: Move ipi header into apic directory Thomas Gleixner
2019-07-25 14:25 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 08/25] x86/apic: Move apic_flat_64 " Thomas Gleixner
2019-07-25 14:25 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 09/25] x86/apic: Consolidate the apic local headers Thomas Gleixner
2019-07-25 14:26 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 10/25] x86/apic/uv: Make x2apic_extra_bits static Thomas Gleixner
2019-07-25 14:27 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 11/25] smp/hotplug: Track booted once CPUs in a cpumask Thomas Gleixner
2019-07-25 14:10 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 12/25] x86/cpu: Move arch_smt_update() to a neutral place Thomas Gleixner
2019-07-25 14:28 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 13/25] x86/hotplug: Silence APIC and NMI when CPU is dead Thomas Gleixner
2019-07-24 15:25 ` [patch V4 " Thomas Gleixner
2019-07-25 14:29 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 14/25] x86/apic: Remove dest argument from __default_send_IPI_shortcut() Thomas Gleixner
2019-07-25 14:29 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 15/25] x86/apic: Add NMI_VECTOR wait to IPI shorthand Thomas Gleixner
2019-07-25 14:30 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 16/25] x86/apic: Move no_ipi_broadcast() out of 32bit Thomas Gleixner
2019-07-25 14:31 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 17/25] x86/apic: Add static key to Control IPI shorthands Thomas Gleixner
2019-07-25 14:31 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 18/25] x86/apic: Provide and use helper for send_IPI_allbutself() Thomas Gleixner
2019-07-25 14:32 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 19/25] cpumask: Implement cpumask_or_equal() Thomas Gleixner
2019-07-25 14:10 ` [tip:smp/hotplug] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 20/25] x86/smp: Move smp_function_call implementations into IPI code Thomas Gleixner
2019-07-25 14:33 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 21/25] x86/smp: Enhance native_send_call_func_ipi() Thomas Gleixner
2019-07-25 14:34 ` tip-bot for Thomas Gleixner [this message]
2019-07-22 18:47 ` [patch V3 22/25] x86/apic: Remove the shorthand decision logic Thomas Gleixner
2019-07-25 14:34 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 23/25] x86/apic: Share common IPI helpers Thomas Gleixner
2019-07-25 14:35 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 24/25] x86/apic/flat64: Remove the IPI shorthand decision logic Thomas Gleixner
2019-07-25 14:36 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-22 18:47 ` [patch V3 25/25] x86/apic/x2apic: Implement IPI shorthands support Thomas Gleixner
2019-07-25 14:37 ` [tip:x86/apic] " tip-bot for Thomas Gleixner
2019-07-25 13:17 ` [patch V3 00/25] x86/apic: Support for IPI shorthands Peter Zijlstra
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