From: Boris Ostrovsky Date: Sat, 23 Mar 2013 13:36:36 +0000 (-0400) Subject: x86, mm: Patch out arch_flush_lazy_mmu_mode() when running on bare metal X-Git-Tag: v3.9-rc7~1^2~3 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=511ba86e1d386f671084b5d0e6f110bb30b8eeb2;p=pandora-kernel.git 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 Link: http://lkml.kernel.org/r/1364045796-10720-2-git-send-email-konrad.wilk@oracle.com Tested-by: Josh Boyer Tested-by: Konrad Rzeszutek Wilk Acked-by: Borislav Petkov Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: H. Peter Anvin Cc: SEE NOTE ABOVE --- Reading git-diff-tree failed