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| author | Dimitri Sivanich <sivanich@sgi.com> | 2009-04-15 10:56:25 -0500 |
|---|---|---|
| committer | Tony Luck <tony.luck@intel.com> | 2009-04-16 11:51:35 -0700 |
| commit | edb91dc01a216e84b78721b71a06db1e0db141b7 (patch) | |
| tree | 9e030d23e6ccac225bce132d4bd5017720d8cfc8 | |
| parent | c4cb768f027706b3a0190309416b13f07114fe56 (diff) | |
| download | op-kernel-dev-edb91dc01a216e84b78721b71a06db1e0db141b7.zip op-kernel-dev-edb91dc01a216e84b78721b71a06db1e0db141b7.tar.gz | |
[IA64] smp_flush_tlb_mm() should only send IPI's to cpus in cpu_vm_mask
Having flush_tlb_mm->smp_flush_tlb_mm() send an IPI to every cpu
on the system is occasionally triggering spin_lock contention in
generic_smp_call_function_interrupt().
Follow x86 arch's lead and only sends IPIs to the cpus in mm->cpu_vm_mask.
Experiments with this change have shown significant improvement in this
contention issue.
Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
| -rw-r--r-- | arch/ia64/kernel/smp.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c index c2d9823..5230eaa 100644 --- a/arch/ia64/kernel/smp.c +++ b/arch/ia64/kernel/smp.c @@ -301,15 +301,12 @@ smp_flush_tlb_mm (struct mm_struct *mm) return; } + smp_call_function_mask(mm->cpu_vm_mask, + (void (*)(void *))local_finish_flush_tlb_mm, mm, 1); + local_irq_disable(); + local_finish_flush_tlb_mm(mm); + local_irq_enable(); preempt_enable(); - /* - * We could optimize this further by using mm->cpu_vm_mask to track which CPUs - * have been running in the address space. It's not clear that this is worth the - * trouble though: to avoid races, we have to raise the IPI on the target CPU - * anyhow, and once a CPU is interrupted, the cost of local_flush_tlb_all() is - * rather trivial. - */ - on_each_cpu((void (*)(void *))local_finish_flush_tlb_mm, mm, 1); } void arch_send_call_function_single_ipi(int cpu) |
