Commit Graph

5 Commits

Author SHA1 Message Date
Adrian Hunter 2a28e23049 perf jit: Add support for using TSC as a timestamp
Intel PT uses TSC as a timestamp, so add support for using TSC instead
of the monotonic clock.  Use of TSC is selected by an environment
variable "JITDUMP_USE_ARCH_TIMESTAMP" and flagged in the jitdump file
with flag JITDUMP_FLAGS_ARCH_TIMESTAMP.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1457426330-30226-1-git-send-email-adrian.hunter@intel.com
[ Added the fixup from He Kuang to make it build on other arches, ]
[ such as aarch64, to avoid inserting this bisectiong breakage upstream ]
Link: http://lkml.kernel.org/r/1459482572-129494-1-git-send-email-hekuang@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-04-01 18:42:55 -03:00
Stephane Eranian 7e9551bc72 perf jvmti: improve error message in Makefile
This patch improves the error message given by jvmti Makefile when the
alternatives command cannot be found. It now suggests the user locates
the root of their Java installation and pass it with JDIR=

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1456378056-18812-1-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-25 10:43:28 -03:00
Stephane Eranian d646ae0a73 perf jvmti: Add check for java alternatives cmd in Makefile
This patch modifies the jvmti makefile to check if the
/usr/sbin/java-update-alternatives utility is present.  If so, then use
it, if not then use the altenatives command.

This helps handle the difference between Ubuntu and Fedora Linux
distributions.

Signed-off-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1455604661-9357-1-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-16 17:12:46 -03:00
Stephane Eranian 598b7c6919 perf jit: add source line info support
This patch adds source line information support to perf for jitted code.

The source line info must be emitted by the runtime, such as JVMTI.

Perf injects extract the source line info from the jitdump file and adds
the corresponding .debug_lines section in the ELF image generated for
each jitted function.

The source line enables matching any address in the profile with a
source file and line number.

The improvement is visible in perf annotate with the source code
displayed alongside the assembly code.

The dwarf code leverages the support from OProfile which is also
released under GPLv2.  Copyright 2007 OProfile authors.

Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Carl Love <cel@us.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John McCutchan <johnmccutchan@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sonny Rao <sonnyrao@chromium.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1448874143-7269-5-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-05 12:33:09 -03:00
Stephane Eranian 209045adc2 perf tools: add JVMTI agent library
This is a standalone JVMTI library to help  profile Java jitted code with perf
record/perf report. The library is not installed or compiled automatically by
perf Makefile. It is not used directly by perf. It is arch agnostic and has
been tested on X86 and ARM. It needs to be used with a Java runtime, such as
OpenJDK, as follows:

  $ java -agentpath:libjvmti.so .......

See the "Committer Notes" below on how to build it.

When used this way, java will generate a jitdump binary file in
$HOME/.debug/java/jit/java-jit-*

This binary dump file contains information to help symbolize and
annotate jitted code.

The jitdump information must be injected into the perf.data file
using:

  $ perf inject --jit -i perf.data -o perf.data.jitted

This injects the MMAP records to cover the jitted code and also generates
one ELF image for each jitted function. The ELF images are created in the
same subdir as the jitdump file. The MMAP records point there too.

Then, to visualize the function or asm profile, simply use the regular
perf commands:

  $ perf report -i perf.data.jitted

or

  $ perf annotate -i perf.data.jitted

JVMTI agent code adapted from the OProfile's opagent code.

This version of the JVMTI agent is using the CLOCK_MONOTONIC as the time
source to timestamp jit samples. To correlate with perf_events samples,
it needs to run on kernel 4.0.0-rc5+ or later with the following commit
from Peter Zijlstra:

  34f439278c ("perf: Add per event clockid support")

With this patch recording jitted code is done as follows:

   $ perf record -k mono -- java -agentpath:libjvmti.so .......

 --------------------------------------------------------------------------

Committer Notes:

Extended testing instructions:

  $ cd tools/perf/jvmti/
  $ dnf install java-devel
  $ make

Then, create some simple java stuff to record some samples:

  $ cat hello.java
  public class hello {
	public static void main(String[] args) {
                 System.out.println("Hello, World");
       	}
  }
  $ javac hello.java
  $ java hello
  Hello, World
  $

And then record it using this jvmti thing:

  $ perf record -k mono java -agentpath:/home/acme/git/linux/tools/perf/jvmti/libjvmti.so hello
  java: jvmti: jitdump in /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jit-1908.dump
  Hello, World
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.030 MB perf.data (268 samples) ]
  $

Now lets insert the PERF_RECORD_MMAP2 records to point jitted mmaps to
files created by the agent:

  $ perf inject --jit -i perf.data -o perf.data.jitted

And finally see that it did its job:

  $ perf report -D -i perf.data.jitted | grep PERF_RECORD_MMAP2 | tail -5
  79197149129422 0xfe10 [0xa0]: PERF_RECORD_MMAP2 1908/1923: [0x7f172428bd60(0x80) @ 0x40 fd:02 1840554 1]: --xs /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-283.so
  79197149235701 0xfeb0 [0xa0]: PERF_RECORD_MMAP2 1908/1923: [0x7f172428ba60(0x180) @ 0x40 fd:02 1840555 1]: --xs /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-284.so
  79197149250558 0xff50 [0xa0]: PERF_RECORD_MMAP2 1908/1923: [0x7f172428b860(0x180) @ 0x40 fd:02 1840556 1]: --xs /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-285.so
  79197149714746 0xfff0 [0xa0]: PERF_RECORD_MMAP2 1908/1923: [0x7f172428b660(0x180) @ 0x40 fd:02 1840557 1]: --xs /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-286.so
  79197149806558 0x10090 [0xa0]: PERF_RECORD_MMAP2 1908/1923: [0x7f172428b460(0x180) @ 0x40 fd:02 1840558 1]: --xs /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-287.so
  $

So:

  $ perf report -D -i perf.data | grep PERF_RECORD_MMAP2 | wc -l
  Failed to open /tmp/perf-1908.map, continuing without symbols
  21
  $ perf report -D -i perf.data.jitted | grep PERF_RECORD_MMAP2 | wc -l
  307
  $ echo $((307 - 21))
  286
  $

286 extra PERF_RECORD_MMAP2 records.

All for thise tiny, with just one function, ELF files:

  $ file /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-9.so
  /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-9.so: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), corrupted program header size, BuildID[sha1]=ae54a2ebc3ecf0ba547bfc8cabdea1519df5203f, not stripped
  $ readelf -sw /home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-9.so

  Symbol table '.symtab' contains 2 entries:
   Num:    Value          Size Type    Bind   Vis      Ndx Name
     0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT  UND
     1: 0000000000000040     9 FUNC    LOCAL  DEFAULT    1 atomic_cmpxchg_long
  $

Inserted into the build-id cache:

  $ ls -la ~/.debug/.build-id/ae/54a2ebc3ecf0ba547bfc8cabdea1519df5203f
  lrwxrwxrwx. 1 acme acme 111 Feb  5 11:30 /home/acme/.debug/.build-id/ae/54a2ebc3ecf0ba547bfc8cabdea1519df5203f -> ../../home/acme/.debug/jit/java-jit-20160205.XXWIEDls/jitted-1908-9.so/ae54a2ebc3ecf0ba547bfc8cabdea1519df5203f

Note: check why 'file' reports that 'corrupted program header size'.

With a stupid java hog to do some profiling:

$ cat hog.java
  public class hog {
	private static double do_something_else(int i) {
		double total = 0;
		while (i > 0) {
			total += Math.log(i--);
		}
		return total;
	}
	private static double do_something(int i) {
		double total = 0;
		while (i > 0) {
			total += Math.sqrt(i--) + do_something_else(i / 100);
		}
		return total;
	}
	public static void main(String[] args) {
		System.out.println(String.format("%s=%f & %f", args[0],
				   do_something(Integer.parseInt(args[0])),
				   do_something_else(Integer.parseInt(args[1]))));
	}
  }
  $ javac hog.java
  $ perf record -F 10000 -g -k mono java -agentpath:/home/acme/git/linux/tools/perf/jvmti/libjvmti.so hog 100000 2345000
  java: jvmti: jitdump in /home/acme/.debug/jit/java-jit-20160205.XX4sqd14/jit-8670.dump
  100000=291561592.669602 & 32050989.778714
  [ perf record: Woken up 6 times to write data ]
  [ perf record: Captured and wrote 1.536 MB perf.data (12538 samples) ]
  $ perf inject --jit -i perf.data -o perf.data.jitted

Looking at the 'perf report' TUI, at one expanded callchain leading
to the jitted code:

  $ perf report --no-children -i perf.data.jitted

Samples: 12K of event 'cycles:pp', Event count (approx.): 3829569932
  Overhead  Comm  Shared Object       Symbol
-   93.38%  java  jitted-8670-291.so  [.] class hog.do_something_else(int)
     class hog.do_something_else(int)
   - Interpreter
      - 75.86% call_stub
           JavaCalls::call_helper
           jni_invoke_static
           jni_CallStaticVoidMethod
           JavaMain
           start_thread
      - 17.52% JavaCalls::call_helper
           jni_invoke_static
           jni_CallStaticVoidMethod
           JavaMain
           start_thread

Signed-off-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Carl Love <cel@us.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John McCutchan <johnmccutchan@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sonny Rao <sonnyrao@chromium.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1448874143-7269-4-git-send-email-eranian@google.com
[ Made it build on fedora23, added some build/usage instructions ]
[ Check if filename != NULL in compiled_method_load_cb, fixing segfault ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-05 12:26:31 -03:00