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=-14.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 C8196C4360C for ; Wed, 2 Oct 2019 20:59:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 99AB121783 for ; Wed, 2 Oct 2019 20:59:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="C+xShXgR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729020AbfJBU7E (ORCPT ); Wed, 2 Oct 2019 16:59:04 -0400 Received: from linux.microsoft.com ([13.77.154.182]:46076 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728495AbfJBU7D (ORCPT ); Wed, 2 Oct 2019 16:59:03 -0400 Received: by linux.microsoft.com (Postfix, from userid 1040) id AB3AF2008710; Wed, 2 Oct 2019 13:59:01 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com AB3AF2008710 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1570049941; bh=6cdP5JQykPhsXL1WHCxNWZjQbGC+Xk2I7XWWY4Qki8Q=; h=From:To:Cc:Subject:Date:From; b=C+xShXgRsfEkSHmQU/gbe1gObYmhOAelOMco4me/BjCfmQ19V9n4lFEBoytjteixA XAVhb8QIJku5Ki3kNhi26ydMEVBh8fEP9N0S3Wk1xIVm+L07pgsy+pJ1w78gHKft/V 22A5Amr+bSpM2BUITmkngh0yYSIy35ynijv2jkPo= From: Steve MacLean Cc: Steve MacLean , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Stephane Eranian , linux-kernel@vger.kernel.org Subject: [PATCH 3/4] perf inject --jit: Remove //anon mmap events Date: Wed, 2 Oct 2019 13:58:21 -0700 Message-Id: <1570049901-115628-1-git-send-email-steve.maclean@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 To: unlisted-recipients:; (no To-header on input) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steve MacLean While a JIT is jitting code it will eventually need to commit more pages and change these pages to executable permissions. Typically the JIT will want these colocated to minimize branch displacements. The kernel will coalesce these anonymous mapping with identical permissions before sending an MMAP event for the new pages. This means the mmap event for the new pages will include the older pages. These anonymous mmap events will obscure the jitdump injected pseudo events. This means that the jitdump generated symbols, machine code, debugging info, and unwind info will no longer be used. Observations: When a process emits a jit dump marker and a jitdump file, the perf-xxx.map file represents inferior information which has been superseded by the jitdump jit-xxx.dump file. Further the '//anon*' mmap events are only required for the legacy perf-xxx.map mapping. Summary: Add rbtree to track which pids have successfully injected a jitdump file. During "perf inject --jit", discard "//anon*" mmap events for any pid which has successfully processed a jitdump file. Committer testing: // jitdump case perf record perf inject --jit --input perf.data --output perfjit.data // verify mmap "//anon" events present initially perf script --input perf.data --show-mmap-events | grep '//anon' // verify mmap "//anon" events removed perf script --input perfjit.data --show-mmap-events | grep '//anon' // no jitdump case perf record perf inject --jit --input perf.data --output perfjit.data // verify mmap "//anon" events present initially perf script --input perf.data --show-mmap-events | grep '//anon' // verify mmap "//anon" events not removed perf script --input perfjit.data --show-mmap-events | grep '//anon' Repro: This issue was discovered while testing the initial CoreCLR jitdump implementation. https://github.com/dotnet/coreclr/pull/26897. Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Cc: linux-kernel@vger.kernel.org Signed-off-by: Steve MacLean --- tools/perf/builtin-inject.c | 4 +-- tools/perf/util/jitdump.c | 63 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 65 insertions(+), 2 deletions(-) diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c index c14f40b8..4c921e0 100644 --- a/tools/perf/builtin-inject.c +++ b/tools/perf/builtin-inject.c @@ -261,7 +261,7 @@ static int perf_event__jit_repipe_mmap(struct perf_tool *tool, * if jit marker, then inject jit mmaps and generate ELF images */ ret = jit_process(inject->session, &inject->output, machine, - event->mmap.filename, sample->pid, &n); + event->mmap.filename, event->mmap.pid, &n); if (ret < 0) return ret; if (ret) { @@ -299,7 +299,7 @@ static int perf_event__jit_repipe_mmap2(struct perf_tool *tool, * if jit marker, then inject jit mmaps and generate ELF images */ ret = jit_process(inject->session, &inject->output, machine, - event->mmap2.filename, sample->pid, &n); + event->mmap2.filename, event->mmap2.pid, &n); if (ret < 0) return ret; if (ret) { diff --git a/tools/perf/util/jitdump.c b/tools/perf/util/jitdump.c index 22d09c4..6a1563f 100644 --- a/tools/perf/util/jitdump.c +++ b/tools/perf/util/jitdump.c @@ -751,6 +751,59 @@ static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr) return 0; } +struct pid_rbtree +{ + struct rb_node node; + pid_t pid; +}; + +static void jit_add_pid(struct rb_root *root, pid_t pid) +{ + struct rb_node **new = &(root->rb_node), *parent = NULL; + struct pid_rbtree* data = NULL; + + /* Figure out where to put new node */ + while (*new) { + struct pid_rbtree *this = container_of(*new, struct pid_rbtree, node); + pid_t nodePid = this->pid; + + parent = *new; + if (pid < nodePid) + new = &((*new)->rb_left); + else if (pid > nodePid) + new = &((*new)->rb_right); + else + return; + } + + data = malloc(sizeof(struct pid_rbtree)); + data->pid = pid; + + /* Add new node and rebalance tree. */ + rb_link_node(&data->node, parent, new); + rb_insert_color(&data->node, root); + + return; +} + +static bool jit_has_pid(struct rb_root *root, pid_t pid) +{ + struct rb_node *node = root->rb_node; + + while (node) { + struct pid_rbtree *this = container_of(node, struct pid_rbtree, node); + pid_t nodePid = this->pid; + + if (pid < nodePid) + node = node->rb_left; + else if (pid > nodePid) + node = node->rb_right; + else + return 1; + } + return 0; +} + int jit_process(struct perf_session *session, struct perf_data *output, @@ -762,12 +815,21 @@ static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr) struct evsel *first; struct jit_buf_desc jd; int ret; + static struct rb_root jitdump_pids = RB_ROOT; /* * first, detect marker mmap (i.e., the jitdump mmap) */ if (jit_detect(filename, pid)) + { + /* + * Strip //anon* mmaps if we processed a jitdump for this pid + */ + if (jit_has_pid(&jitdump_pids, pid) && (strncmp(filename, "//anon", 6) == 0)) + return 1; + return 0; + } memset(&jd, 0, sizeof(jd)); @@ -786,6 +848,7 @@ static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr) ret = jit_inject(&jd, filename); if (!ret) { + jit_add_pid(&jitdump_pids, pid); *nbytes = jd.bytes_written; ret = 1; } -- 1.8.3.1