From mboxrd@z Thu Jan 1 00:00:00 1970 From: xiakaixu Subject: Re: Does perf support different length of user-space hw_breakpoint? Date: Wed, 14 May 2014 10:55:09 +0800 Message-ID: <5372DB0D.5070206@huawei.com> References: <53707DD6.2000108@huawei.com> <20140513120046.GB1138@krava.brq.redhat.com> <20140513150613.GC13828@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20140513150613.GC13828@localhost.localdomain> Sender: linux-kernel-owner@vger.kernel.org To: Frederic Weisbecker Cc: Jiri Olsa , Suravee Suthikulpanit , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, paulus@samba.org, Ingo Molnar , a.p.zijlstra@chello.nl, Arnaldo Carvalho de Melo , Borislav Petkov , Namhyung Kim , Huxinwei , peifeiyue@huawei.com List-Id: linux-perf-users.vger.kernel.org =E4=BA=8E 2014/5/13 23:06, Frederic Weisbecker =E5=86=99=E9=81=93: > On Tue, May 13, 2014 at 02:00:46PM +0200, Jiri Olsa wrote: >> On Mon, May 12, 2014 at 03:52:54PM +0800, xiakaixu wrote: >>> Hi guys, >>> >>> Does perf support different length of user-space hw_breakpoint, >>> such as HW_BREAKPOINT_LEN_1/HW_BREAKPOINT_LEN_2/HW_BREAKPOINT_LEN_= 4/ >>> HW_BREAKPOINT_LEN_8? >>> >>> Seems perf only support HW_BREAKPOINT_LEN_4/sizeof(long) >>> by default from the source code and simple test. >> >> right.. >> >> /* >> * We should find a nice way to override the access length >> * Provide some defaults for now >> */ >> if (attr.bp_type =3D=3D HW_BREAKPOINT_X) >> attr.bp_len =3D sizeof(long); >> else >> attr.bp_len =3D HW_BREAKPOINT_LEN_4; >> >>> >>> May I have your opinions if I want to trace different bytes of >>> hw_breakpoint addr? >> >> I guess that depends on what you want to do ;-) >=20 > Ah, I have a patchset from Jacob Shin and Suravee Suthikulpanit that = does > that. Also it has been hanging around for too long by my fault. I'm p= osting > it now. Thanks for your reply! Hopefully I can get it ASAP. > . >=20