From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756886AbZDWSEU (ORCPT ); Thu, 23 Apr 2009 14:04:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753816AbZDWSEC (ORCPT ); Thu, 23 Apr 2009 14:04:02 -0400 Received: from sous-sol.org ([216.99.217.87]:57786 "EHLO sequoia.sous-sol.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753301AbZDWSEA (ORCPT ); Thu, 23 Apr 2009 14:04:00 -0400 Date: Thu, 23 Apr 2009 11:02:38 -0700 From: Chris Wright To: Chris Wright Cc: Jeremy Fitzhardinge , Steven Rostedt , Ingo Molnar , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , LKML , Andrew Morton , Glauber de Oliveira Costa , Rusty Russell , Pekka Enberg Subject: Re: [PATCH 0/2] [GIT PULL] tracing: various bug fixes Message-ID: <20090423180238.GS3036@sequoia.sous-sol.org> References: <20090421082354.GC12512@elte.hu> <20090421094616.GA14561@elte.hu> <20090423082031.GA599@elte.hu> <49F09C35.1080006@goop.org> <20090423172138.GR3036@sequoia.sous-sol.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090423172138.GR3036@sequoia.sous-sol.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Chris Wright (chrisw@sous-sol.org) wrote: > * Jeremy Fitzhardinge (jeremy@goop.org) wrote: > > OK, the good news is that its not a callee-save calling convention > > problem, which is what I feared. But it does sound pretty awkward to > > fix. Does __native_flush_tlb_global() have to use > > raw_local_irq_save/restore? > > Vaguely related...makes sense to do native_(read/write)_cr4 since it's > the native tlb flushing implementation, no? > > looks ok from inspection, not tested yet... BTW, Steve, does that fix it for you? Sure makes the code cleaner: 410: 0f 20 e2 mov %cr4,%rdx 413: 48 89 d0 mov %rdx,%rax 416: 24 7f and $0x7f,%al 418: 0f 22 e0 mov %rax,%cr4 41b: 0f 22 e2 mov %rdx,%cr4 thanks, -chris > Subject: [PATCH] x86: use native register access for native tlb flushing > > currently these are paravirtulaized, doesn't appear any callers rely on > this (no pv_ops backends are using native_tlb and overriding cr3/4 > access). > > Signed-off-by: Chris Wright > --- > arch/x86/include/asm/tlbflush.h | 8 ++++---- > 1 files changed, 4 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h > index 16a5c84..a5ecc9c 100644 > --- a/arch/x86/include/asm/tlbflush.h > +++ b/arch/x86/include/asm/tlbflush.h > @@ -17,7 +17,7 @@ > > static inline void __native_flush_tlb(void) > { > - write_cr3(read_cr3()); > + native_write_cr3(native_read_cr3()); > } > > static inline void __native_flush_tlb_global(void) > @@ -32,11 +32,11 @@ static inline void __native_flush_tlb_global(void) > */ > raw_local_irq_save(flags); > > - cr4 = read_cr4(); > + cr4 = native_read_cr4(); > /* clear PGE */ > - write_cr4(cr4 & ~X86_CR4_PGE); > + native_write_cr4(cr4 & ~X86_CR4_PGE); > /* write old PGE again and flush TLBs */ > - write_cr4(cr4); > + native_write_cr4(cr4); > > raw_local_irq_restore(flags); > }