Commit-ID: 57d9b1b43433a6ba7267c80b87d8e8f6e86edceb Gitweb: http://git.kernel.org/tip/57d9b1b43433a6ba7267c80b87d8e8f6e86edceb Author: Michael S. Tsirkin <mst@xxxxxxxxxx> AuthorDate: Thu, 28 Jan 2016 19:02:44 +0200 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Fri, 29 Jan 2016 09:40:10 +0100 locking/x86: Tweak the comment about use of wmb() for IO On x86, we *do* still use the non-NOP rmb()/wmb() for IO barriers, but even that is generally questionable. Leave them around as historial unless somebody can point to a case where they care about the performance, but tweak the comment so people don't think they are strictly required in all cases. Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Cc: Davidlohr Bueso <dbueso@xxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: virtualization <virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/1453921746-16178-4-git-send-email-mst@xxxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/include/asm/barrier.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h index a291745..bfb28ca 100644 --- a/arch/x86/include/asm/barrier.h +++ b/arch/x86/include/asm/barrier.h @@ -6,7 +6,7 @@ /* * Force strict CPU ordering. - * And yes, this is required on UP too when we're talking + * And yes, this might be required on UP too when we're talking * to devices. */ _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
