From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3tXrmC51p6zDvxT for ; Tue, 6 Dec 2016 17:08:43 +1100 (AEDT) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id uB663cbx098418 for ; Tue, 6 Dec 2016 01:08:41 -0500 Received: from e32.co.us.ibm.com (e32.co.us.ibm.com [32.97.110.150]) by mx0b-001b2d01.pphosted.com with ESMTP id 275pymb282-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 06 Dec 2016 01:08:40 -0500 Received: from localhost by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 5 Dec 2016 23:08:40 -0700 Subject: Re: [PATCH v8 2/3] perf annotate: Support jump instruction with target as second operand To: acme@kernel.org, kim.phillips@arm.com References: <1480953407-7605-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com> <1480953407-7605-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com> Cc: peterz@infradead.org, mingo@redhat.com, alexander.shishkin@linux.intel.com, chris.ryder@arm.com, mhiramat@kernel.org, treeze.taeung@gmail.com, markus@trippelsdorf.de, naveen.n.rao@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Ravi Bangoria From: Ravi Bangoria Date: Tue, 6 Dec 2016 11:38:28 +0530 MIME-Version: 1.0 In-Reply-To: <1480953407-7605-2-git-send-email-ravi.bangoria@linux.vnet.ibm.com> Content-Type: text/plain; charset=UTF-8 Message-Id: <584655DC.5030502@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Arnaldo, Hmm, so it's difficult to find example of this when we use debuginfo. Because... Jump__parse tries to look for two things 'offset' and 'target address'. objdump with debuginfo will include offset in assembly f.e. annotate of 'smp_call_function_single' with perf.data and vmlinux I shared. │c00000000016d6ac: cmpwi cr7,r9,0 ▒ │c00000000016d6b0: ↑ bne cr7,c00000000016d59c <.smp_call_function_single+0x8c> ▒ │c00000000016d6b4: addis r10,r2,-15 ▒ objdump of same function with kcore. │c00000000016d6ac: cmpwi cr7,r9,0 ▒ │c00000000016d6b0: ↓ bne cr7,0xc00000000016d59c ▒ │c00000000016d6b4: addis r10,r2,-15 ▒ Annotating in first case won't show any issue because we directly get offset. But in this case as well, we are parsing wrong target address in ops->target.addr While we don't have offset in second case, we use target address to find it. And thus it shows wrong o/p something like: │ cmpwi cr7,r9,0 ▒ │ ↓ bne 3fffffffffe92afc ▒ │ addis r10,r2,-15 ▒ BTW, we have lot of such instructions in kernel. Thanks, -Ravi On Monday 05 December 2016 09:26 PM, Ravi Bangoria wrote: > Arch like powerpc has jump instructions that includes target address > as second operand. For example, 'bne cr7,0xc0000000000f6154'. Add > support for such instruction in perf annotate. > > objdump o/p: > c0000000000f6140: ld r9,1032(r31) > c0000000000f6144: cmpdi cr7,r9,0 > c0000000000f6148: bne cr7,0xc0000000000f6154 > c0000000000f614c: ld r9,2312(r30) > c0000000000f6150: std r9,1032(r31) > c0000000000f6154: ld r9,88(r31) > > Corresponding perf annotate o/p: > > Before patch: > ld r9,1032(r31) > cmpdi cr7,r9,0 > v bne 3ffffffffff09f2c > ld r9,2312(r30) > std r9,1032(r31) > 74: ld r9,88(r31) > > After patch: > ld r9,1032(r31) > cmpdi cr7,r9,0 > v bne 74 > ld r9,2312(r30) > std r9,1032(r31) > 74: ld r9,88(r31) > > Signed-off-by: Ravi Bangoria > --- > Changes in v8: > - v7: https://lkml.org/lkml/2016/9/21/436 > - Rebase to acme/perf/core > - Little change in patch description. > - No logical changes. (Cross arch annotate patches are in. This patch > is for hardening annotate for powerpc.) > > tools/perf/util/annotate.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c > index ea7e0de..590244e 100644 > --- a/tools/perf/util/annotate.c > +++ b/tools/perf/util/annotate.c > @@ -223,8 +223,12 @@ bool ins__is_call(const struct ins *ins) > static int jump__parse(struct arch *arch __maybe_unused, struct ins_operands *ops, struct map *map __maybe_unused) > { > const char *s = strchr(ops->raw, '+'); > + const char *c = strchr(ops->raw, ','); > > - ops->target.addr = strtoull(ops->raw, NULL, 16); > + if (c++ != NULL) > + ops->target.addr = strtoull(c, NULL, 16); > + else > + ops->target.addr = strtoull(ops->raw, NULL, 16); > > if (s++ != NULL) > ops->target.offset = strtoull(s, NULL, 16);