Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754071Ab3DVV54 (ORCPT ); Mon, 22 Apr 2013 17:57:56 -0400 Received: from co9ehsobe004.messaging.microsoft.com ([207.46.163.27]:33008 "EHLO co9outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753556Ab3DVV5y (ORCPT ); Mon, 22 Apr 2013 17:57:54 -0400 X-Forefront-Antispam-Report: CIP:163.181.249.108;KIP:(null);UIP:(null);IPV:NLI;H:ausb3twp01.amd.com;RD:none;EFVD:NLI X-SpamScore: -10 X-BigFish: VPS-10(zz98dI1432I4015I111aI179dNzz1f42h1fc6h1ee6h1de0h1fdah1202h1e76h1d1ah1d2ahzzz2dh668h839h944hd25hd2bhf0ah1220h1288h12a5h12a9h12bdh137ah13b6h1441h1504h1537h153bh162dh1631h1758h18e1h1946h19b5h1ad9h1b0ah1155h) X-WSS-ID: 0MLOFOA-01-288-02 X-M-MSG: Date: Mon, 22 Apr 2013 16:57:44 -0500 From: Jacob Shin To: Oleg Nesterov CC: Ingo Molnar , Peter Zijlstra , Arnaldo Carvalho de Melo , "H. Peter Anvin" , Thomas Gleixner , "x86@kernel.org" , Stephane Eranian , Jiri Olsa , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 1/5] perf: Add hardware breakpoint address mask Message-ID: <20130422215744.GA26823@jshin-Toonie> References: <1365528113-5458-1-git-send-email-jacob.shin@amd.com> <20130420165334.GA14814@redhat.com> <20130420224757.GB6155@jshin-Toonie> <20130421170202.GA5358@redhat.com> <20130422213715.GA24256@jshin-Toonie> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20130422213715.GA24256@jshin-Toonie> User-Agent: Mutt/1.5.21 (2010-09-15) X-OriginatorOrg: amd.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1995 Lines: 67 On Mon, Apr 22, 2013 at 04:37:15PM -0500, Jacob Shin wrote: > On Sun, Apr 21, 2013 at 07:02:02PM +0200, Oleg Nesterov wrote: > > On 04/20, Jacob Shin wrote: > > > > > > On Sat, Apr 20, 2013 at 06:53:34PM +0200, Oleg Nesterov wrote: > > > > > > > > And does attr.bp_len "contribute" to the mask? > > > > > > > > I mean, if bp_len == X86_BREAKPOINT_LEN_8, does this mean that > > > > bp_bp_addr_mask and (bp_bp_addr_mask | 7) have the same effect? > > > > > > Yes it has the same effect. > > > > OK, thanks... > > > > So this is the "natural" extension. Given that currently bp_addr > > should be aligned, bp_len could be already bp_mask but I guess it > > is too late to change this, so we need another field. > > > > Hmm. Perhaps arch_has_hw_breakpoint_addr_mask(void) should be turned > > into arch_validate_hw_breakpoint_addr_mask(bp) which should also > > check that (bp_addr & bp_addr_mask) == 0. But I won't insist. > > Yes I can do that .. in that case should the Kconfig > CONFIG_HAVE_HW_BREAKPOINT_ADDR_MASK go away, and in every non-x86 > hw_breakpoint.c do: > > bool arch_validate_hw_breakpoint_addr_mask(struct perf_event *bp) > { > return false; Sorry, of course what I meant was, return bp->attr.bp_addr_mask == 0; > } > > ? > > Or keep CONFIG_HAVE_HW_BREAKPOINT_ADDR_MASK and in > include/linux/hw_breakpoint.h do: > > #ifndef CONFIG_HAVE_HW_BREAKPOINT_ADDR_MASK > static inline bool arch_validate_hw_breakpoint_addr_mask(struct perf_event *bp) > { > return falase; here too. > } > #endif > > ? > > Thanks, Just reading your other email, you said a __weak function would suffice. So I'll do that .. sorry for answering my own question. I'll send out a revised patchset sometime later tonight .. Thanks again! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/