summaryrefslogtreecommitdiff
path: root/arch/x86/xen/mmu.c
diff options
context:
space:
mode:
authorBoris Ostrovsky <boris.ostrovsky@oracle.com>2013-03-23 09:36:36 -0400
committerH. Peter Anvin <hpa@linux.intel.com>2013-04-10 11:25:10 -0700
commit511ba86e1d386f671084b5d0e6f110bb30b8eeb2 (patch)
tree1fe3621ebaf43ad5fb5ab644500676f2f158153f /arch/x86/xen/mmu.c
parent1160c2779b826c6f5c08e5cc542de58fd1f667d5 (diff)
x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metal
Invoking arch_flush_lazy_mmu_mode() results in calls to preempt_enable()/disable() which may have performance impact. Since lazy MMU is not used on bare metal we can patch away arch_flush_lazy_mmu_mode() so that it is never called in such environment. [ hpa: the previous patch "Fix vmalloc_fault oops during lazy MMU updates" may cause a minor performance regression on bare metal. This patch resolves that performance regression. It is somewhat unclear to me if this is a good -stable candidate. ] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: http://lkml.kernel.org/r/1364045796-10720-2-git-send-email-konrad.wilk@oracle.com Tested-by: Josh Boyer <jwboyer@redhat.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> SEE NOTE ABOVE
Diffstat (limited to 'arch/x86/xen/mmu.c')
-rw-r--r--arch/x86/xen/mmu.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 6afbb2ca9a0a..2f5d6875555e 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -2196,6 +2196,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
.lazy_mode = {
.enter = paravirt_enter_lazy_mmu,
.leave = xen_leave_lazy_mmu,
+ .flush = paravirt_flush_lazy_mmu,
},
.set_fixmap = xen_set_fixmap,