linux_dsm_epyc7002/tools/perf/util/genelf.h
Stephane Eranian 9b07e27f88 perf inject: Add jitdump mmap injection support
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

Note that jitdump.h support is not limited to Java, it works with any
jitted environment modified to emit the jitdump file format, include
those where code can be jitted multiple times and moved around.

The jitdump.h format is adapted from the Oprofile project.

The genelf.c (ELF binary generation) depends on MD5 hash encoding for
the buildid. To enable this, libssl-dev must be installed. If not, then
genelf.c defaults to using urandom to generate the buildid, which is not
ideal.  The Makefile auto-detects the presence on libssl-dev.

This version mmaps the jitdump file to create a marker MMAP record in
the perf.data file. The marker is used to detect jitdump and cause perf
inject to inject the jitted mmaps and generate ELF images for jitted
functions.

In V8, the following fixes and changes were made among other things:

  -  the jidump header format include a new flags field to be used
     to carry information about the configuration of the runtime agent.
     Contributed by: Adrian Hunter <adrian.hunter@intel.com>

  - Fix mmap pgoff: MMAP event pgoff must be the offset within the ELF file
    at which the code resides.
    Contributed by: Adrian Hunter <adrian.hunter@intel.com>

  - Fix ELF virtual addresses: perf tools expect the ELF virtual addresses of dynamic
    objects to match the file offset.
    Contributed by: Adrian Hunter <adrian.hunter@intel.com>

  - JIT MMAP injection does not obey finished_round semantics. JIT MMAP injection injects all
    MMAP events in one go, so it does not obey finished_round semantics, so drop the
    finished_round events from the output perf.data file.
    Contributed by: Adrian Hunter <adrian.hunter@intel.com>

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/1448874143-7269-3-git-send-email-eranian@google.com
[ Moved inject.build_ids ordering bits to a separate patch, fixed the NO_LIBELF=1 build ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-05 09:46:45 -03:00

64 lines
1.7 KiB
C

#ifndef __GENELF_H__
#define __GENELF_H__
/* genelf.c */
extern int jit_write_elf(int fd, uint64_t code_addr, const char *sym,
const void *code, int csize);
#if defined(__arm__)
#define GEN_ELF_ARCH EM_ARM
#define GEN_ELF_ENDIAN ELFDATA2LSB
#define GEN_ELF_CLASS ELFCLASS32
#elif defined(__aarch64__)
#define GEN_ELF_ARCH EM_AARCH64
#define GEN_ELF_ENDIAN ELFDATA2LSB
#define GEN_ELF_CLASS ELFCLASS64
#elif defined(__x86_64__)
#define GEN_ELF_ARCH EM_X86_64
#define GEN_ELF_ENDIAN ELFDATA2LSB
#define GEN_ELF_CLASS ELFCLASS64
#elif defined(__i386__)
#define GEN_ELF_ARCH EM_386
#define GEN_ELF_ENDIAN ELFDATA2LSB
#define GEN_ELF_CLASS ELFCLASS32
#elif defined(__ppcle__)
#define GEN_ELF_ARCH EM_PPC
#define GEN_ELF_ENDIAN ELFDATA2LSB
#define GEN_ELF_CLASS ELFCLASS64
#elif defined(__powerpc__)
#define GEN_ELF_ARCH EM_PPC64
#define GEN_ELF_ENDIAN ELFDATA2MSB
#define GEN_ELF_CLASS ELFCLASS64
#elif defined(__powerpcle__)
#define GEN_ELF_ARCH EM_PPC64
#define GEN_ELF_ENDIAN ELFDATA2LSB
#define GEN_ELF_CLASS ELFCLASS64
#else
#error "unsupported architecture"
#endif
#if GEN_ELF_CLASS == ELFCLASS64
#define elf_newehdr elf64_newehdr
#define elf_getshdr elf64_getshdr
#define Elf_Ehdr Elf64_Ehdr
#define Elf_Shdr Elf64_Shdr
#define Elf_Sym Elf64_Sym
#define ELF_ST_TYPE(a) ELF64_ST_TYPE(a)
#define ELF_ST_BIND(a) ELF64_ST_BIND(a)
#define ELF_ST_VIS(a) ELF64_ST_VISIBILITY(a)
#else
#define elf_newehdr elf32_newehdr
#define elf_getshdr elf32_getshdr
#define Elf_Ehdr Elf32_Ehdr
#define Elf_Shdr Elf32_Shdr
#define Elf_Sym Elf32_Sym
#define ELF_ST_TYPE(a) ELF32_ST_TYPE(a)
#define ELF_ST_BIND(a) ELF32_ST_BIND(a)
#define ELF_ST_VIS(a) ELF32_ST_VISIBILITY(a)
#endif
/* The .text section is directly after the ELF header */
#define GEN_ELF_TEXT_OFFSET sizeof(Elf_Ehdr)
#endif