From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A668C0044C for ; Wed, 31 Oct 2018 14:17:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD3C52081B for ; Wed, 31 Oct 2018 14:17:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CD3C52081B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729492AbeJaXPZ (ORCPT ); Wed, 31 Oct 2018 19:15:25 -0400 Received: from mga09.intel.com ([134.134.136.24]:38183 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729385AbeJaXPZ (ORCPT ); Wed, 31 Oct 2018 19:15:25 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 31 Oct 2018 07:17:12 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,447,1534834800"; d="scan'208";a="277206257" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.130]) ([10.237.72.130]) by fmsmga006.fm.intel.com with ESMTP; 31 Oct 2018 07:17:10 -0700 Subject: Re: [PATCH 4/5] perf intel-pt: Insert callchain context into synthesized callchains To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Andi Kleen , linux-kernel@vger.kernel.org, leo.yan@linaro.org, David Miller , Mathieu Poirier References: <20181031091043.23465-1-adrian.hunter@intel.com> <20181031091043.23465-5-adrian.hunter@intel.com> <20181031132803.GG10660@kernel.org> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: <850eed86-fb8f-e328-316c-378890d4f15f@intel.com> Date: Wed, 31 Oct 2018 16:15:26 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181031132803.GG10660@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 31/10/18 3:28 PM, Arnaldo Carvalho de Melo wrote: > Em Wed, Oct 31, 2018 at 11:10:42AM +0200, Adrian Hunter escreveu: >> In the absence of a fallback, callchains must encode also the callchain >> context. Do that now there is no fallback. > > So, this one is independent of the first 3 patches, right? Yes. I was just going to test it separately when I noticed I had screwed up my earlier testing. When I re-tested I discovered this patch has an off-by-one error: diff --git a/tools/perf/util/thread-stack.c b/tools/perf/util/thread-stack.c index afdf36852ac8..61a4286a74dc 100644 --- a/tools/perf/util/thread-stack.c +++ b/tools/perf/util/thread-stack.c @@ -337,7 +337,7 @@ void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, last_context = context; - for (i = 2, j = 0; i < sz && j < thread->ts->cnt; i++, j++) { + for (i = 2, j = 1; i < sz && j <= thread->ts->cnt; i++, j++) { ip = thread->ts->stack[thread->ts->cnt - j].ret_addr; context = callchain_context(ip, kernel_start); if (context != last_context) { Shall I send V2? > So, this one is independent of the first 3 patches, right? Ok, applying > it first, I'll relook the first ones next. > > - Arnaldo > >> Signed-off-by: Adrian Hunter >> Cc: stable@vger.kernel.org # 4.19 >> --- >> tools/perf/util/intel-pt.c | 6 +++-- >> tools/perf/util/thread-stack.c | 44 +++++++++++++++++++++++++++------- >> tools/perf/util/thread-stack.h | 2 +- >> 3 files changed, 40 insertions(+), 12 deletions(-) >> >> diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c >> index ffa385a029b3..60732213d16a 100644 >> --- a/tools/perf/util/intel-pt.c >> +++ b/tools/perf/util/intel-pt.c >> @@ -759,7 +759,8 @@ static struct intel_pt_queue *intel_pt_alloc_queue(struct intel_pt *pt, >> if (pt->synth_opts.callchain) { >> size_t sz = sizeof(struct ip_callchain); >> >> - sz += pt->synth_opts.callchain_sz * sizeof(u64); >> + /* Add 1 to callchain_sz for callchain context */ >> + sz += (pt->synth_opts.callchain_sz + 1) * sizeof(u64); >> ptq->chain = zalloc(sz); >> if (!ptq->chain) >> goto out_free; >> @@ -1160,7 +1161,8 @@ static void intel_pt_prep_sample(struct intel_pt *pt, >> >> if (pt->synth_opts.callchain) { >> thread_stack__sample(ptq->thread, ptq->chain, >> - pt->synth_opts.callchain_sz, sample->ip); >> + pt->synth_opts.callchain_sz + 1, >> + sample->ip, pt->kernel_start); >> sample->callchain = ptq->chain; >> } >> >> diff --git a/tools/perf/util/thread-stack.c b/tools/perf/util/thread-stack.c >> index c091635bf7dc..afdf36852ac8 100644 >> --- a/tools/perf/util/thread-stack.c >> +++ b/tools/perf/util/thread-stack.c >> @@ -310,20 +310,46 @@ void thread_stack__free(struct thread *thread) >> } >> } >> >> +static inline u64 callchain_context(u64 ip, u64 kernel_start) >> +{ >> + return ip < kernel_start ? PERF_CONTEXT_USER : PERF_CONTEXT_KERNEL; >> +} >> + >> void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, >> - size_t sz, u64 ip) >> + size_t sz, u64 ip, u64 kernel_start) >> { >> - size_t i; >> + u64 context = callchain_context(ip, kernel_start); >> + u64 last_context; >> + size_t i, j; >> >> - if (!thread || !thread->ts) >> - chain->nr = 1; >> - else >> - chain->nr = min(sz, thread->ts->cnt + 1); >> + if (sz < 2) { >> + chain->nr = 0; >> + return; >> + } >> >> - chain->ips[0] = ip; >> + chain->ips[0] = context; >> + chain->ips[1] = ip; >> + >> + if (!thread || !thread->ts) { >> + chain->nr = 2; >> + return; >> + } >> + >> + last_context = context; >> + >> + for (i = 2, j = 0; i < sz && j < thread->ts->cnt; i++, j++) { >> + ip = thread->ts->stack[thread->ts->cnt - j].ret_addr; >> + context = callchain_context(ip, kernel_start); >> + if (context != last_context) { >> + if (i >= sz - 1) >> + break; >> + chain->ips[i++] = context; >> + last_context = context; >> + } >> + chain->ips[i] = ip; >> + } >> >> - for (i = 1; i < chain->nr; i++) >> - chain->ips[i] = thread->ts->stack[thread->ts->cnt - i].ret_addr; >> + chain->nr = i; >> } >> >> struct call_return_processor * >> diff --git a/tools/perf/util/thread-stack.h b/tools/perf/util/thread-stack.h >> index b7e41c4ebfdd..f97c00a8c251 100644 >> --- a/tools/perf/util/thread-stack.h >> +++ b/tools/perf/util/thread-stack.h >> @@ -84,7 +84,7 @@ int thread_stack__event(struct thread *thread, u32 flags, u64 from_ip, >> u64 to_ip, u16 insn_len, u64 trace_nr); >> void thread_stack__set_trace_nr(struct thread *thread, u64 trace_nr); >> void thread_stack__sample(struct thread *thread, struct ip_callchain *chain, >> - size_t sz, u64 ip); >> + size_t sz, u64 ip, u64 kernel_start); >> int thread_stack__flush(struct thread *thread); >> void thread_stack__free(struct thread *thread); >> size_t thread_stack__depth(struct thread *thread); >> -- >> 2.17.1 >