summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/tlbflush.h
diff options
context:
space:
mode:
authorAndy Lutomirski <luto@kernel.org>2016-01-29 22:42:59 +0300
committerBen Hutchings <ben@decadent.org.uk>2018-01-09 03:35:08 +0300
commit11bf931565496d63bbdda6ac197f3e72d2e38800 (patch)
tree3f1f6e34594806b52649be995a56f3e7d6387c99 /arch/x86/include/asm/tlbflush.h
parent9372713cde0513cf07f413660c734a9622e7543a (diff)
downloadlinux-11bf931565496d63bbdda6ac197f3e72d2e38800.tar.xz
x86/mm: If INVPCID is available, use it to flush global mappings
commit d8bced79af1db6734f66b42064cc773cada2ce99 upstream. On my Skylake laptop, INVPCID function 2 (flush absolutely everything) takes about 376ns, whereas saving flags, twiddling CR4.PGE to flush global mappings, and restoring flags takes about 539ns. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/ed0ef62581c0ea9c99b9bf6df726015e96d44743.1454096309.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'arch/x86/include/asm/tlbflush.h')
-rw-r--r--arch/x86/include/asm/tlbflush.h9
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index deea3edc3d85..5683dd017a41 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -127,6 +127,15 @@ static inline void __native_flush_tlb_global(void)
{
unsigned long flags;
+ if (static_cpu_has(X86_FEATURE_INVPCID)) {
+ /*
+ * Using INVPCID is considerably faster than a pair of writes
+ * to CR4 sandwiched inside an IRQ flag save/restore.
+ */
+ invpcid_flush_all();
+ return;
+ }
+
/*
* Read-modify-write to CR4 - protect it from preemption and
* from interrupts. (Use the raw variant because this code can