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jvmti_agent.c
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Ben Gainey authoredtools/perf/jvmti is broken in so far as it generates incorrect debug information. Specifically it attributes all debug lines to the original method being output even in the case that some code is being inlined from elsewhere. This patch fixes the issue. To test (from within linux/tools/perf): export JDIR=/usr/lib/jvm/java-8-openjdk-amd64/ make cat << __EOF > Test.java public class Test { private StringBuilder b = new StringBuilder(); private void loop(int i, String... args) { for (String a : args) b.append(a); long hc = b.hashCode() * System.nanoTime(); b = new StringBuilder(); b.append(hc); System.out.printf("Iteration %d = %d\n", i, hc); } public void run(String... args) { for (int i = 0; i < 10000; ++i) { loop(i, args); } } public static void main(String... args) { Test t = new Test(); t.run(args); } } __EOF $JDIR/bin/javac Test.java ./perf record -F 10000 -g -k mono $JDIR/bin/java -agentpath:`pwd`/libperf-jvmti.so Test ./perf inject --jit -i perf.data -o perf.data.jitted ./perf annotate -i perf.data.jitted --stdio | grep Test\.java: | sort -u Before this patch, Test.java line numbers get reported that are greater than the number of lines in the Test.java file. They come from the source file of the inlined function, e.g. java/lang/String.java:1085. For further validation one can examine those lines in the JDK source distribution and confirm that they map to inlined functions called by Test.java. After this patch, the filename of the inlined function is output rather than the incorrect original source filename. Signed-off-by:
Ben Gainey <ben.gainey@arm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Colin King <colin.king@canonical.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 598b7c69 ("perf jit: add source line info support")
Link: http://lkml.kernel.org/r/20171122182541.d25599a3eb1ada3480d142fa@arm.com
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>Ben Gainey authoredtools/perf/jvmti is broken in so far as it generates incorrect debug information. Specifically it attributes all debug lines to the original method being output even in the case that some code is being inlined from elsewhere. This patch fixes the issue. To test (from within linux/tools/perf): export JDIR=/usr/lib/jvm/java-8-openjdk-amd64/ make cat << __EOF > Test.java public class Test { private StringBuilder b = new StringBuilder(); private void loop(int i, String... args) { for (String a : args) b.append(a); long hc = b.hashCode() * System.nanoTime(); b = new StringBuilder(); b.append(hc); System.out.printf("Iteration %d = %d\n", i, hc); } public void run(String... args) { for (int i = 0; i < 10000; ++i) { loop(i, args); } } public static void main(String... args) { Test t = new Test(); t.run(args); } } __EOF $JDIR/bin/javac Test.java ./perf record -F 10000 -g -k mono $JDIR/bin/java -agentpath:`pwd`/libperf-jvmti.so Test ./perf inject --jit -i perf.data -o perf.data.jitted ./perf annotate -i perf.data.jitted --stdio | grep Test\.java: | sort -u Before this patch, Test.java line numbers get reported that are greater than the number of lines in the Test.java file. They come from the source file of the inlined function, e.g. java/lang/String.java:1085. For further validation one can examine those lines in the JDK source distribution and confirm that they map to inlined functions called by Test.java. After this patch, the filename of the inlined function is output rather than the incorrect original source filename. Signed-off-by:Ben Gainey <ben.gainey@arm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Colin King <colin.king@canonical.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 598b7c69 ("perf jit: add source line info support")
Link: http://lkml.kernel.org/r/20171122182541.d25599a3eb1ada3480d142fa@arm.com
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
jvmti_agent.c 9.17 KiB
/*
* jvmti_agent.c: JVMTI agent interface
*
* Adapted from the Oprofile code in opagent.c:
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Copyright 2007 OProfile authors
* Jens Wilke
* Daniel Hansel
* Copyright IBM Corporation 2007
*/
#include <sys/types.h>
#include <sys/stat.h> /* for mkdir() */
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <stdint.h>
#include <limits.h>
#include <fcntl.h>
#include <unistd.h>
#include <time.h>
#include <sys/mman.h>
#include <syscall.h> /* for gettid() */
#include <err.h>
#include "jvmti_agent.h"
#include "../util/jitdump.h"
#define JIT_LANG "java"
static char jit_path[PATH_MAX];
static void *marker_addr;
static inline pid_t gettid(void)
{
return (pid_t)syscall(__NR_gettid);
}
static int get_e_machine(struct jitheader *hdr)
{
ssize_t sret;
char id[16];
int fd, ret = -1;
struct {
uint16_t e_type;
uint16_t e_machine;
} info;
fd = open("/proc/self/exe", O_RDONLY);
if (fd == -1)
return -1;
sret = read(fd, id, sizeof(id));
if (sret != sizeof(id))
goto error;
/* check ELF signature */