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=-15.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 2B34DCA9EAF for ; Mon, 21 Oct 2019 13:39:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F31032173B for ; Mon, 21 Oct 2019 13:39:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571665186; bh=Rwj/0TzeTdBBfSeXoLYRN52d0cGcmDv2pCCuwnyyM+k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1X1dON+hITAnmFmTBxDM0c2/+KbLrXZaP69j+J0SOeA9jwZtBZLAogzUqqtkm4IyE 8Fg0UHjs75asc0LqIqMcNQKJNFANUg+e3BdpoksABHqtRSY03UILaWgXEGL0Mlkqhs oVMmcDvkC/vDg6bGOE6YkASPLk05iwlNZECI99ek= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729325AbfJUNjo (ORCPT ); Mon, 21 Oct 2019 09:39:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:41284 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729312AbfJUNjm (ORCPT ); Mon, 21 Oct 2019 09:39:42 -0400 Received: from quaco.ghostprotocols.net (unknown [179.97.35.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 56D6D21929; Mon, 21 Oct 2019 13:39:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571665180; bh=Rwj/0TzeTdBBfSeXoLYRN52d0cGcmDv2pCCuwnyyM+k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=s2OQGTV/swRWJ8OOyeJUcC/VjsWOlFdarifeCBQoKkcR9b4ryeCTtoXWAOSmnNY10 HbIT4qD5RvbH88m6i551OSoxvwj/V9qFFOR7ou6ubL3G/PptOQTkK2OMdd2LdEu6es cnkah6NXNXy7d/MsN8IFlUz7IMvTRqJ1IkrWdQdM= From: Arnaldo Carvalho de Melo To: Ingo Molnar , Thomas Gleixner Cc: Jiri Olsa , Namhyung Kim , Clark Williams , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Arnaldo Carvalho de Melo , Adrian Hunter , Andi Kleen , David Ahern , =?UTF-8?q?Luis=20Cl=C3=A1udio=20Gon=C3=A7alves?= Subject: [PATCH 18/57] perf trace: Support tracepoint dynamic char arrays Date: Mon, 21 Oct 2019 10:37:55 -0300 Message-Id: <20191021133834.25998-19-acme@kernel.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191021133834.25998-1-acme@kernel.org> References: <20191021133834.25998-1-acme@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnaldo Carvalho de Melo Things like: # grep __data_loc /sys/kernel/debug/tracing/events/sched/sched_process_exec/format field:__data_loc char[] filename; offset:8; size:4; signed:1; # That, at that offset (8) and with that size(8) have an integer that contains the real length and offset for the contents of that array. Now this works: # perf trace --max-events 1 -e sched:*exec -a 0.000 sed/19441 sched:sched_process_exec(filename: "/usr/bin/sync", pid: 19441 (sync), old_pid: 19441 (sync)) # As when using the libtraceevent based beautifier: # perf trace --libtraceevent --max-events 1 -e sched:*exec -a 0.000 sync/19463 sched:sched_process_exec(filename=/usr/bin/sync pid=19463 old_pid=19463) # I.e. that 'filename' is implemented as a dynamic char array. Cc: Adrian Hunter Cc: Andi Kleen Cc: David Ahern Cc: Jiri Olsa Cc: Luis Cláudio Gonçalves Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-950p0m842fe6n7sxsdwqj5i2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 19 ++++++++++++++----- tools/perf/trace/beauty/beauty.h | 2 ++ 2 files changed, 16 insertions(+), 5 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index cdee22dac2b3..907eaf316f5b 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -563,7 +563,7 @@ static size_t syscall_arg__scnprintf_char_array(char *bf, size_t size, struct sy // XXX Hey, maybe for sched:sched_switch prev/next comm fields we can // fill missing comms using thread__set_comm()... // here or in a special syscall_arg__scnprintf_pid_sched_tp... - return scnprintf(bf, size, "\"%-.*s\"", arg->fmt->nr_entries, arg->val); + return scnprintf(bf, size, "\"%-.*s\"", arg->fmt->nr_entries ?: arg->len, arg->val); } #define SCA_CHAR_ARRAY syscall_arg__scnprintf_char_array @@ -1559,7 +1559,7 @@ syscall_arg_fmt__init_array(struct syscall_arg_fmt *arg, struct tep_format_field arg->scnprintf = SCA_PID; else if (strcmp(field->type, "umode_t") == 0) arg->scnprintf = SCA_MODE_T; - else if ((field->flags & TEP_FIELD_IS_ARRAY) && strstarts(field->type, "char")) { + else if ((field->flags & TEP_FIELD_IS_ARRAY) && strstr(field->type, "char")) { arg->scnprintf = SCA_CHAR_ARRAY; arg->nr_entries = field->arraylen; } else if ((strcmp(field->type, "int") == 0 || @@ -2523,10 +2523,19 @@ static size_t trace__fprintf_tp_fields(struct trace *trace, struct evsel *evsel, if (syscall_arg.mask & bit) continue; + syscall_arg.len = 0; syscall_arg.fmt = arg; - if (field->flags & TEP_FIELD_IS_ARRAY) - val = (uintptr_t)(sample->raw_data + field->offset); - else + if (field->flags & TEP_FIELD_IS_ARRAY) { + int offset = field->offset; + + if (field->flags & TEP_FIELD_IS_DYNAMIC) { + offset = format_field__intval(field, sample, evsel->needs_swap); + syscall_arg.len = offset >> 16; + offset &= 0xffff; + } + + val = (uintptr_t)(sample->raw_data + offset); + } else val = format_field__intval(field, sample, evsel->needs_swap); /* * Some syscall args need some mask, most don't and diff --git a/tools/perf/trace/beauty/beauty.h b/tools/perf/trace/beauty/beauty.h index 77ad80a399fd..0dee0cf4fda8 100644 --- a/tools/perf/trace/beauty/beauty.h +++ b/tools/perf/trace/beauty/beauty.h @@ -87,6 +87,7 @@ struct syscall_arg_fmt; /** * @val: value of syscall argument being formatted + * @len: for tracepoint dynamic arrays, if fmt->nr_entries == 0, then its not a fixed array, look at arg->len * @args: All the args, use syscall_args__val(arg, nth) to access one * @augmented_args: Extra data that can be collected, for instance, with eBPF for expanding the pathname for open, etc * @augmented_args_size: augmented_args total payload size @@ -109,6 +110,7 @@ struct syscall_arg { struct thread *thread; struct trace *trace; void *parm; + u16 len; u8 idx; u8 mask; bool show_string_prefix; -- 2.21.0