From 0e21990ae7ee11af94f44f240b06e520cf1505d4 Mon Sep 17 00:00:00 2001
From: Mike Travis <travis@sgi.com>
Date: Sat, 10 Jan 2009 21:58:10 -0800
Subject: [PATCH] SGI UV cpumask: use static temp cpumask in flush_tlb
Impact: Improve tlb flush performance for UV
Calling alloc_cpumask_var a zillion times a second does affect
performance. Replace with static cpumask.
Note: when CONFIG_X86_UV is defined, this extra PER_CPU memory
will be optimized out for non-UV configs as is_uv_system() will
then return a constant 0.
Signed-off-by: Mike Travis <travis@sgi.com>
---
arch/x86/kernel/tlb_64.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/tlb_64.c b/arch/x86/kernel/tlb_64.c
index 38836aef51b4..7a3f9891302d 100644
--- a/arch/x86/kernel/tlb_64.c
+++ b/arch/x86/kernel/tlb_64.c
@@ -202,16 +202,17 @@ void native_flush_tlb_others(const struct cpumask *cpumask,
struct mm_struct *mm, unsigned long va)
{
if (is_uv_system()) {
- cpumask_var_t after_uv_flush;
+ /* FIXME: could be an percpu_alloc'd thing */
+ static DEFINE_PER_CPU(cpumask_t, flush_tlb_mask);
+ struct cpumask *after_uv_flush = &get_cpu_var(flush_tlb_mask);
- if (alloc_cpumask_var(&after_uv_flush, GFP_ATOMIC)) {
- cpumask_andnot(after_uv_flush,
- cpumask, cpumask_of(smp_processor_id()));
- if (!uv_flush_tlb_others(after_uv_flush, mm, va))
- flush_tlb_others_ipi(after_uv_flush, mm, va);
- free_cpumask_var(after_uv_flush);
- return;
- }
+ cpumask_andnot(after_uv_flush, cpumask,
+ cpumask_of(smp_processor_id()));
+ if (!uv_flush_tlb_others(after_uv_flush, mm, va))
+ flush_tlb_others_ipi(after_uv_flush, mm, va);
+
+ put_cpu_var(flush_tlb_uv_cpumask);
+ return;
}
flush_tlb_others_ipi(cpumask, mm, va);
}