Re: [PATCH v8 2/4] perf inject: add jitdump mmap injection support

[Arnaldo Carvalho de Melo]

Em Fri, Jan 22, 2016 at 01:22:51PM -0800, Stephane Eranian escreveu:
> On Fri, Jan 22, 2016 at 12:44 PM, Arnaldo Carvalho de Melo
> <acme@xxxxxxxxxx> wrote:
> > Em Mon, Nov 30, 2015 at 10:02:21AM +0100, Stephane Eranian escreveu:
> >> This patch adds a --jit/-j option to perf inject.
> >>
> >> This options injects MMAP records into the perf.data
> >> file to cover the jitted code mmaps. It also emits
> >> ELF images for each function in the jidump file.
> >> Those images are created where the jitdump file is.
> >> The MMAP records point to that location as well.
> >>
> >> Typical flow:
> >> $ perf record -k mono -- java -agentpath:libpjvmti.so java_class
> >> $ perf inject --jit -i perf.data -o perf.data.jitted
> >> $ perf report -i perf.data.jitted
> >
> > So, it fails 'make -C tools/perf build-test', specifically the one where
> > we ask for a NO_LIBELF build, trying to fix:
> >
> I have rebase to tip.git last night. Will try your branch today.
> Will add a couple of minor adjustments and also better documentation
> on how to use it.

So, trying to continue with this, digged for instructions on how to
build this the libjvmti.so thing, figure out its java-devel (aka
java-1.8.0-openjdk-devel).

And I needed this to build it, hacky tho, as was what was there before,
BTW, what distro was it you tested this for that
update-java-alternatives to be available?

I'm keeping what I have a perf/jit branch in my git tree.

- Arnaldo


diff --git a/tools/perf/jvmti/Makefile b/tools/perf/jvmti/Makefile
index 5e46f518e045..d7005f1608d2 100644
--- a/tools/perf/jvmti/Makefile
+++ b/tools/perf/jvmti/Makefile
@@ -33,7 +33,8 @@ VLIBJVMTI=libjvmti.so.$(VERSION)
 SLDFLAGS=-shared -Wl,-soname -Wl,$(VLIBJVMTI)
 SOLIBEXT=so
 
-JDIR=$(shell /usr/sbin/update-java-alternatives -l | head -1 | cut -d ' ' -f 3)
+#JDIR=$(shell /usr/sbin/update-java-alternatives -l | head -1 | cut -d ' ' -f 3)
+JDIR=$(shell alternatives --display java | tail -1 | cut -d' ' -f 5 | sed 's%/jre/bin/java.%%g')
 # -lrt required in 32-bit mode for clock_gettime()
 LIBS=-lelf -lrt
 INCDIR=-I $(JDIR)/include -I $(JDIR)/include/linux