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: NStephane 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: NArnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/perf-inject.txt

@@ -53,6 +53,13 @@ include::itrace.txt[]
 --strip::
 	Use with --itrace to strip out non-synthesized events.
 
+-j::
+--jit::
+	Process jitdump files by injecting the mmap records corresponding to jitted
+	functions. This option also generates the ELF images for each jitted function
+	found in the jitdumps files captured in the input perf.data file. Use this option
+	if you are monitoring environment using JIT runtimes, such as Java, DART or V8.
+
 SEE ALSO
 --------
 linkperf:perf-record[1], linkperf:perf-report[1], linkperf:perf-archive[1]

tools/perf/builtin-inject.c

@@ -17,6 +17,7 @@
 #include "util/build-id.h"
 #include "util/data.h"
 #include "util/auxtrace.h"
+#include "util/jit.h"
 
 #include <subcmd/parse-options.h>
 
@@ -29,6 +30,7 @@ struct perf_inject {
 	bool			sched_stat;
 	bool			have_auxtrace;
 	bool			strip;
+	bool			jit_mode;
 	const char		*input_name;
 	struct perf_data_file	output;
 	u64			bytes_written;
@@ -71,6 +73,15 @@ static int perf_event__repipe_oe_synth(struct perf_tool *tool,
 	return perf_event__repipe_synth(tool, event);
 }
 
+#ifdef HAVE_LIBELF_SUPPORT
+static int perf_event__drop_oe(struct perf_tool *tool __maybe_unused,
+			       union perf_event *event __maybe_unused,
+			       struct ordered_events *oe __maybe_unused)
+{
+	return 0;
+}
+#endif
+
 static int perf_event__repipe_op2_synth(struct perf_tool *tool,
 					union perf_event *event,
 					struct perf_session *session
@@ -234,6 +245,27 @@ static int perf_event__repipe_mmap(struct perf_tool *tool,
 	return err;
 }
 
+#ifdef HAVE_LIBELF_SUPPORT
+static int perf_event__jit_repipe_mmap(struct perf_tool *tool,
+				       union perf_event *event,
+				       struct perf_sample *sample,
+				       struct machine *machine)
+{
+	struct perf_inject *inject = container_of(tool, struct perf_inject, tool);
+	u64 n = 0;
+
+	/*
+	 * if jit marker, then inject jit mmaps and generate ELF images
+	 */
+	if (!jit_process(inject->session, &inject->output, machine,
+			 event->mmap.filename, sample->pid, &n)) {
+		inject->bytes_written += n;
+		return 0;
+	}
+	return perf_event__repipe_mmap(tool, event, sample, machine);
+}
+#endif
+
 static int perf_event__repipe_mmap2(struct perf_tool *tool,
 				   union perf_event *event,
 				   struct perf_sample *sample,
@@ -247,6 +279,27 @@ static int perf_event__repipe_mmap2(struct perf_tool *tool,
 	return err;
 }
 
+#ifdef HAVE_LIBELF_SUPPORT
+static int perf_event__jit_repipe_mmap2(struct perf_tool *tool,
+					union perf_event *event,
+					struct perf_sample *sample,
+					struct machine *machine)
+{
+	struct perf_inject *inject = container_of(tool, struct perf_inject, tool);
+	u64 n = 0;
+
+	/*
+	 * if jit marker, then inject jit mmaps and generate ELF images
+	 */
+	if (!jit_process(inject->session, &inject->output, machine,
+			  event->mmap2.filename, sample->pid, &n)) {
+		inject->bytes_written += n;
+		return 0;
+	}
+	return perf_event__repipe_mmap2(tool, event, sample, machine);
+}
+#endif
+
 static int perf_event__repipe_fork(struct perf_tool *tool,
 				   union perf_event *event,
 				   struct perf_sample *sample,
@@ -664,6 +717,23 @@ static int __cmd_inject(struct perf_inject *inject)
 	return ret;
 }
 
+#ifdef HAVE_LIBELF_SUPPORT
+static int
+jit_validate_events(struct perf_session *session)
+{
+	struct perf_evsel *evsel;
+
+	/*
+	 * check that all events use CLOCK_MONOTONIC
+	 */
+	evlist__for_each(session->evlist, evsel) {
+		if (evsel->attr.use_clockid == 0 || evsel->attr.clockid != CLOCK_MONOTONIC)
+			return -1;
+	}
+	return 0;
+}
+#endif
+
 int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
 {
 	struct perf_inject inject = {
@@ -703,7 +773,7 @@ int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
 	};
 	int ret;
 
-	const struct option options[] = {
+	struct option options[] = {
 		OPT_BOOLEAN('b', "build-ids", &inject.build_ids,
 			    "Inject build-ids into the output stream"),
 		OPT_STRING('i', "input", &inject.input_name, "file",
@@ -713,6 +783,7 @@ int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
 		OPT_BOOLEAN('s', "sched-stat", &inject.sched_stat,
 			    "Merge sched-stat and sched-switch for getting events "
 			    "where and how long tasks slept"),
+		OPT_BOOLEAN('j', "jit", &inject.jit_mode, "merge jitdump files into perf.data file"),
 		OPT_INCR('v', "verbose", &verbose,
 			 "be more verbose (show build ids, etc)"),
 		OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name, "file",
@@ -729,7 +800,9 @@ int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
 		"perf inject [<options>]",
 		NULL
 	};
-
+#ifndef HAVE_LIBELF_SUPPORT
+	set_option_nobuild(options, 'j', "jit", "NO_LIBELF=1", true);
+#endif
 	argc = parse_options(argc, argv, options, inject_usage, 0);
 
 	/*
@@ -765,7 +838,26 @@ int cmd_inject(int argc, const char **argv, const char *prefix __maybe_unused)
 		inject.tool.ordered_events = true;
 		inject.tool.ordering_requires_timestamps = true;
 	}
-
+#ifdef HAVE_LIBELF_SUPPORT
+	if (inject.jit_mode) {
+		/*
+		 * validate event is using the correct clockid
+		 */
+		if (jit_validate_events(inject.session)) {
+			fprintf(stderr, "error, jitted code must be sampled with perf record -k 1\n");
+			return -1;
+		}
+		inject.tool.mmap2	   = perf_event__jit_repipe_mmap2;
+		inject.tool.mmap	   = perf_event__jit_repipe_mmap;
+		inject.tool.ordered_events = true;
+		inject.tool.ordering_requires_timestamps = true;
+		/*
+		 * JIT MMAP injection injects all MMAP events in one go, so it
+		 * does not obey finished_round semantics.
+		 */
+		inject.tool.finished_round = perf_event__drop_oe;
+	}
+#endif
 	ret = symbol__init(&inject.session->header.env);
 	if (ret < 0)
 		goto out_delete;

tools/perf/util/Build

@@ -106,6 +106,8 @@ libperf-y += scripting-engines/
 libperf-$(CONFIG_ZLIB) += zlib.o
 libperf-$(CONFIG_LZMA) += lzma.o
 libperf-y += demangle-java.o
+libperf-$(CONFIG_LIBELF) += jitdump.o
+libperf-$(CONFIG_LIBELF) += genelf.o
 
 CFLAGS_config.o   += -DETC_PERFCONFIG="BUILD_STR($(ETC_PERFCONFIG_SQ))"
 

tools/perf/util/genelf.c

+/*
+ * genelf.c
+ * Copyright (C) 2014, Google, Inc
+ *
+ * Contributed by:
+ * 	Stephane Eranian <eranian@gmail.com>
+ *
+ * Released under the GPL v2. (and only v2, not any later version)
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <stddef.h>
+#include <libelf.h>
+#include <string.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <err.h>
+#include <dwarf.h>
+
+#include "perf.h"
+#include "genelf.h"
+#include "../util/jitdump.h"
+
+#define JVMTI
+
+#define BUILD_ID_URANDOM /* different uuid for each run */
+
+#ifdef HAVE_LIBCRYPTO
+
+#define BUILD_ID_MD5
+#undef BUILD_ID_SHA	/* does not seem to work well when linked with Java */
+#undef BUILD_ID_URANDOM /* different uuid for each run */
+
+#ifdef BUILD_ID_SHA
+#include <openssl/sha.h>
+#endif
+
+#ifdef BUILD_ID_MD5
+#include <openssl/md5.h>
+#endif
+#endif
+
+
+typedef struct {
+  unsigned int namesz;  /* Size of entry's owner string */
+  unsigned int descsz;  /* Size of the note descriptor */
+  unsigned int type;    /* Interpretation of the descriptor */
+  char         name[0]; /* Start of the name+desc data */
+} Elf_Note;
+
+struct options {
+	char *output;
+	int fd;
+};
+
+static char shd_string_table[] = {
+	0,
+	'.', 't', 'e', 'x', 't', 0,			/*  1 */
+	'.', 's', 'h', 's', 't', 'r', 't', 'a', 'b', 0, /*  7 */
+	'.', 's', 'y', 'm', 't', 'a', 'b', 0,		/* 17 */
+	'.', 's', 't', 'r', 't', 'a', 'b', 0,		/* 25 */
+	'.', 'n', 'o', 't', 'e', '.', 'g', 'n', 'u', '.', 'b', 'u', 'i', 'l', 'd', '-', 'i', 'd', 0, /* 33 */
+	'.', 'd', 'e', 'b', 'u', 'g', '_', 'l', 'i', 'n', 'e', 0, /* 52 */
+	'.', 'd', 'e', 'b', 'u', 'g', '_', 'i', 'n', 'f', 'o', 0, /* 64 */
+	'.', 'd', 'e', 'b', 'u', 'g', '_', 'a', 'b', 'b', 'r', 'e', 'v', 0, /* 76 */
+};
+
+static struct buildid_note {
+	Elf_Note desc;		/* descsz: size of build-id, must be multiple of 4 */
+	char	 name[4];	/* GNU\0 */
+	char	 build_id[20];
+} bnote;
+
+static Elf_Sym symtab[]={
+	/* symbol 0 MUST be the undefined symbol */
+	{ .st_name  = 0, /* index in sym_string table */
+	  .st_info  = ELF_ST_TYPE(STT_NOTYPE),
+	  .st_shndx = 0, /* for now */
+	  .st_value = 0x0,
+	  .st_other = ELF_ST_VIS(STV_DEFAULT),
+	  .st_size  = 0,
+	},
+	{ .st_name  = 1, /* index in sym_string table */
+	  .st_info  = ELF_ST_BIND(STB_LOCAL) | ELF_ST_TYPE(STT_FUNC),
+	  .st_shndx = 1,
+	  .st_value = 0, /* for now */
+	  .st_other = ELF_ST_VIS(STV_DEFAULT),
+	  .st_size  = 0, /* for now */
+	}
+};
+
+#ifdef BUILD_ID_URANDOM
+static void
+gen_build_id(struct buildid_note *note,
+	     unsigned long load_addr __maybe_unused,
+	     const void *code __maybe_unused,
+	     size_t csize __maybe_unused)
+{
+	int fd;
+	size_t sz = sizeof(note->build_id);
+	ssize_t sret;
+
+	fd = open("/dev/urandom", O_RDONLY);
+	if (fd == -1)
+		err(1, "cannot access /dev/urandom for builid");
+
+	sret = read(fd, note->build_id, sz);
+
+	close(fd);
+
+	if (sret != (ssize_t)sz)
+		memset(note->build_id, 0, sz);
+}
+#endif
+
+#ifdef BUILD_ID_SHA
+static void
+gen_build_id(struct buildid_note *note,
+	     unsigned long load_addr __maybe_unused,
+	     const void *code,
+	     size_t csize)
+{
+	if (sizeof(note->build_id) < SHA_DIGEST_LENGTH)
+		errx(1, "build_id too small for SHA1");
+
+	SHA1(code, csize, (unsigned char *)note->build_id);
+}
+#endif
+
+#ifdef BUILD_ID_MD5
+static void
+gen_build_id(struct buildid_note *note, unsigned long load_addr, const void *code, size_t csize)
+{
+	MD5_CTX context;
+
+	if (sizeof(note->build_id) < 16)
+		errx(1, "build_id too small for MD5");
+
+	MD5_Init(&context);
+	MD5_Update(&context, &load_addr, sizeof(load_addr));
+	MD5_Update(&context, code, csize);
+	MD5_Final((unsigned char *)note->build_id, &context);
+}
+#endif
+
+/*
+ * fd: file descriptor open for writing for the output file
+ * load_addr: code load address (could be zero, just used for buildid)
+ * sym: function name (for native code - used as the symbol)
+ * code: the native code
+ * csize: the code size in bytes
+ */
+int
+jit_write_elf(int fd, uint64_t load_addr, const char *sym,
+	      const void *code, int csize)
+{
+	Elf *e;
+	Elf_Data *d;
+	Elf_Scn *scn;
+	Elf_Ehdr *ehdr;
+	Elf_Shdr *shdr;
+	char *strsym = NULL;
+	int symlen;
+	int retval = -1;
+
+	if (elf_version(EV_CURRENT) == EV_NONE) {
+		warnx("ELF initialization failed");
+		return -1;
+	}
+
+	e = elf_begin(fd, ELF_C_WRITE, NULL);
+	if (!e) {
+		warnx("elf_begin failed");
+		goto error;
+	}
+
+	/*
+	 * setup ELF header
+	 */
+	ehdr = elf_newehdr(e);
+	if (!ehdr) {
+		warnx("cannot get ehdr");
+		goto error;
+	}
+
+	ehdr->e_ident[EI_DATA] = GEN_ELF_ENDIAN;
+	ehdr->e_ident[EI_CLASS] = GEN_ELF_CLASS;
+	ehdr->e_machine = GEN_ELF_ARCH;
+	ehdr->e_type = ET_DYN;
+	ehdr->e_entry = GEN_ELF_TEXT_OFFSET;
+	ehdr->e_version = EV_CURRENT;
+	ehdr->e_shstrndx= 2; /* shdr index for section name */
+
+	/*
+	 * setup text section
+	 */
+	scn = elf_newscn(e);
+	if (!scn) {
+		warnx("cannot create section");
+		goto error;
+	}
+
+	d = elf_newdata(scn);
+	if (!d) {
+		warnx("cannot get new data");
+		goto error;
+	}
+
+	d->d_align = 16;
+	d->d_off = 0LL;
+	d->d_buf = (void *)code;
+	d->d_type = ELF_T_BYTE;
+	d->d_size = csize;
+	d->d_version = EV_CURRENT;
+
+	shdr = elf_getshdr(scn);
+	if (!shdr) {
+		warnx("cannot get section header");
+		goto error;
+	}
+
+	shdr->sh_name = 1;
+	shdr->sh_type = SHT_PROGBITS;
+	shdr->sh_addr = GEN_ELF_TEXT_OFFSET;
+	shdr->sh_flags = SHF_EXECINSTR | SHF_ALLOC;
+	shdr->sh_entsize = 0;
+
+	/*
+	 * setup section headers string table
+	 */
+	scn = elf_newscn(e);
+	if (!scn) {
+		warnx("cannot create section");
+		goto error;
+	}
+
+	d = elf_newdata(scn);
+	if (!d) {
+		warnx("cannot get new data");
+		goto error;
+	}
+
+	d->d_align = 1;
+	d->d_off = 0LL;
+	d->d_buf = shd_string_table;
+	d->d_type = ELF_T_BYTE;
+	d->d_size = sizeof(shd_string_table);
+	d->d_version = EV_CURRENT;
+
+	shdr = elf_getshdr(scn);
+	if (!shdr) {
+		warnx("cannot get section header");
+		goto error;
+	}
+
+	shdr->sh_name = 7; /* offset of '.shstrtab' in shd_string_table */
+	shdr->sh_type = SHT_STRTAB;
+	shdr->sh_flags = 0;
+	shdr->sh_entsize = 0;
+
+	/*
+	 * setup symtab section
+	 */
+	symtab[1].st_size  = csize;
+	symtab[1].st_value = GEN_ELF_TEXT_OFFSET;
+
+	scn = elf_newscn(e);
+	if (!scn) {
+		warnx("cannot create section");
+		goto error;
+	}
+
+	d = elf_newdata(scn);
+	if (!d) {
+		warnx("cannot get new data");
+		goto error;
+	}
+
+	d->d_align = 8;
+	d->d_off = 0LL;
+	d->d_buf = symtab;
+	d->d_type = ELF_T_SYM;
+	d->d_size = sizeof(symtab);
+	d->d_version = EV_CURRENT;
+
+	shdr = elf_getshdr(scn);
+	if (!shdr) {
+		warnx("cannot get section header");
+		goto error;
+	}
+
+	shdr->sh_name = 17; /* offset of '.symtab' in shd_string_table */
+	shdr->sh_type = SHT_SYMTAB;
+	shdr->sh_flags = 0;
+	shdr->sh_entsize = sizeof(Elf_Sym);
+	shdr->sh_link = 4; /* index of .strtab section */
+
+	/*
+	 * setup symbols string table
+	 * 2 = 1 for 0 in 1st entry, 1 for the 0 at end of symbol for 2nd entry
+	 */
+	symlen = 2 + strlen(sym);
+	strsym = calloc(1, symlen);
+	if (!strsym) {
+		warnx("cannot allocate strsym");
+		goto error;
+	}
+	strcpy(strsym + 1, sym);
+
+	scn = elf_newscn(e);
+	if (!scn) {
+		warnx("cannot create section");
+		goto error;
+	}
+
+	d = elf_newdata(scn);
+	if (!d) {
+		warnx("cannot get new data");
+		goto error;
+	}
+
+	d->d_align = 1;
+	d->d_off = 0LL;
+	d->d_buf = strsym;
+	d->d_type = ELF_T_BYTE;
+	d->d_size = symlen;
+	d->d_version = EV_CURRENT;
+
+	shdr = elf_getshdr(scn);
+	if (!shdr) {
+		warnx("cannot get section header");
+		goto error;
+	}
+
+	shdr->sh_name = 25; /* offset in shd_string_table */
+	shdr->sh_type = SHT_STRTAB;
+	shdr->sh_flags = 0;
+	shdr->sh_entsize = 0;
+
+	/*
+	 * setup build-id section
+	 */
+	scn = elf_newscn(e);
+	if (!scn) {
+		warnx("cannot create section");
+		goto error;
+	}
+
+	d = elf_newdata(scn);
+	if (!d) {
+		warnx("cannot get new data");
+		goto error;
+	}
+
+	/*
+	 * build-id generation
+	 */
+	gen_build_id(&bnote, load_addr, code, csize);
+	bnote.desc.namesz = sizeof(bnote.name); /* must include 0 termination */
+	bnote.desc.descsz = sizeof(bnote.build_id);
+	bnote.desc.type   = NT_GNU_BUILD_ID;
+	strcpy(bnote.name, "GNU");
+
+	d->d_align = 4;
+	d->d_off = 0LL;
+	d->d_buf = &bnote;
+	d->d_type = ELF_T_BYTE;
+	d->d_size = sizeof(bnote);
+	d->d_version = EV_CURRENT;
+
+	shdr = elf_getshdr(scn);
+	if (!shdr) {
+		warnx("cannot get section header");
+		goto error;
+	}
+
+	shdr->sh_name = 33; /* offset in shd_string_table */
+	shdr->sh_type = SHT_NOTE;
+	shdr->sh_addr = 0x0;
+	shdr->sh_flags = SHF_ALLOC;
+	shdr->sh_size = sizeof(bnote);
+	shdr->sh_entsize = 0;
+
+	if (elf_update(e, ELF_C_WRITE) < 0) {
+		warnx("elf_update 4 failed");
+		goto error;
+	}
+
+	retval = 0;
+error:
+	(void)elf_end(e);
+
+	free(strsym);
+
+
+	return retval;
+}
+
+#ifndef JVMTI
+
+static unsigned char x86_code[] = {
+    0xBB, 0x2A, 0x00, 0x00, 0x00, /* movl $42, %ebx */
+    0xB8, 0x01, 0x00, 0x00, 0x00, /* movl $1, %eax */
+    0xCD, 0x80            /* int $0x80 */
+};
+
+static struct options options;
+
+int main(int argc, char **argv)
+{
+	int c, fd, ret;
+
+	while ((c = getopt(argc, argv, "o:h")) != -1) {
+		switch (c) {
+		case 'o':
+			options.output = optarg;
+			break;
+		case 'h':
+			printf("Usage: genelf -o output_file [-h]\n");
+			return 0;
+		default:
+			errx(1, "unknown option");
+		}
+	}
+
+	fd = open(options.output, O_CREAT|O_TRUNC|O_RDWR, 0666);
+	if (fd == -1)
+		err(1, "cannot create file %s", options.output);
+
+	ret = jit_write_elf(fd, "main", x86_code, sizeof(x86_code));
+	close(fd);
+
+	if (ret != 0)
+		unlink(options.output);
+
+	return ret;
+}
+#endif

tools/perf/util/genelf.h

+#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

tools/perf/util/jit.h

+#ifndef __JIT_H__
+#define __JIT_H__
+
+#include <data.h>
+
+extern int jit_process(struct perf_session *session,
+		       struct perf_data_file *output,
+		       struct machine *machine,
+		       char *filename,
+		       pid_t pid,
+		       u64 *nbytes);
+
+extern int jit_inject_record(const char *filename);
+
+#endif /* __JIT_H__ */

tools/perf/util/jitdump.c

+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <byteswap.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+
+#include "util.h"
+#include "event.h"
+#include "debug.h"
+#include "evlist.h"
+#include "symbol.h"
+#include "strlist.h"
+#include <elf.h>
+
+#include "session.h"
+#include "jit.h"
+#include "jitdump.h"
+#include "genelf.h"
+#include "../builtin.h"
+
+struct jit_buf_desc {
+	struct perf_data_file *output;
+	struct perf_session *session;
+	struct machine *machine;
+	union jr_entry   *entry;
+	void             *buf;
+	uint64_t	 sample_type;
+	size_t           bufsize;
+	FILE             *in;
+	bool		 needs_bswap; /* handles cross-endianess */
+	void		 *debug_data;
+	size_t		 nr_debug_entries;
+	uint32_t         code_load_count;
+	u64		 bytes_written;
+	struct rb_root   code_root;
+	char		 dir[PATH_MAX];
+};
+
+struct debug_line_info {
+	unsigned long vma;
+	unsigned int lineno;
+	/* The filename format is unspecified, absolute path, relative etc. */
+	char const filename[0];
+};
+
+struct jit_tool {
+	struct perf_tool tool;
+	struct perf_data_file	output;
+	struct perf_data_file	input;
+	u64 bytes_written;
+};
+
+#define hmax(a, b) ((a) > (b) ? (a) : (b))
+#define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
+
+static int
+jit_emit_elf(char *filename,
+	     const char *sym,
+	     uint64_t code_addr,
+	     const void *code,
+	     int csize)
+{
+	int ret, fd;
+
+	if (verbose > 0)
+		fprintf(stderr, "write ELF image %s\n", filename);
+
+	fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
+	if (fd == -1) {
+		pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(errno));
+		return -1;
+	}
+
+        ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize);
+
+        close(fd);
+
+        if (ret)
+                unlink(filename);
+
+	return ret;
+}
+
+static void
+jit_close(struct jit_buf_desc *jd)
+{
+	if (!(jd && jd->in))
+		return;
+	funlockfile(jd->in);
+	fclose(jd->in);
+	jd->in = NULL;
+}
+
+static int
+jit_open(struct jit_buf_desc *jd, const char *name)
+{
+	struct jitheader header;
+	struct jr_prefix *prefix;
+	ssize_t bs, bsz = 0;
+	void *n, *buf = NULL;
+	int ret, retval = -1;
+
+	jd->in = fopen(name, "r");
+	if (!jd->in)
+		return -1;
+
+	bsz = hmax(sizeof(header), sizeof(*prefix));
+
+	buf = malloc(bsz);
+	if (!buf)
+		goto error;
+
+	/*
+	 * protect from writer modifying the file while we are reading it
+	 */
+	flockfile(jd->in);
+
+	ret = fread(buf, sizeof(header), 1, jd->in);
+	if (ret != 1)
+		goto error;
+
+	memcpy(&header, buf, sizeof(header));
+
+	if (header.magic != JITHEADER_MAGIC) {
+		if (header.magic != JITHEADER_MAGIC_SW)
+			goto error;
+		jd->needs_bswap = true;
+	}
+
+	if (jd->needs_bswap) {
+		header.version    = bswap_32(header.version);
+		header.total_size = bswap_32(header.total_size);
+		header.pid	  = bswap_32(header.pid);
+		header.elf_mach   = bswap_32(header.elf_mach);
+		header.timestamp  = bswap_64(header.timestamp);
+		header.flags      = bswap_64(header.flags);
+	}
+
+	if (verbose > 2)
+		pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\n",
+			header.version,
+			header.total_size,
+			(unsigned long long)header.timestamp,
+			header.pid,
+			header.elf_mach);
+
+	if (header.flags & JITDUMP_FLAGS_RESERVED) {
+		pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
+		       (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
+		goto error;
+	}
+
+	bs = header.total_size - sizeof(header);
+
+	if (bs > bsz) {
+		n = realloc(buf, bs);
+		if (!n)
+			goto error;
+		bsz = bs;
+		buf = n;
+		/* read extra we do not know about */
+		ret = fread(buf, bs - bsz, 1, jd->in);
+		if (ret != 1)
+			goto error;
+	}
+	/*
+	 * keep dirname for generating files and mmap records
+	 */
+	strcpy(jd->dir, name);
+	dirname(jd->dir);
+
+	return 0;
+error:
+	funlockfile(jd->in);
+	fclose(jd->in);
+	return retval;
+}
+
+static union jr_entry *
+jit_get_next_entry(struct jit_buf_desc *jd)
+{
+	struct jr_prefix *prefix;
+	union jr_entry *jr;
+	void *addr;
+	size_t bs, size;
+	int id, ret;
+
+	if (!(jd && jd->in))
+		return NULL;
+
+	if (jd->buf == NULL) {
+		size_t sz = getpagesize();
+		if (sz < sizeof(*prefix))
+			sz = sizeof(*prefix);
+
+		jd->buf = malloc(sz);
+		if (jd->buf == NULL)
+			return NULL;
+
+		jd->bufsize = sz;
+	}
+
+	prefix = jd->buf;
+
+	/*
+	 * file is still locked at this point
+	 */
+	ret = fread(prefix, sizeof(*prefix), 1, jd->in);
+	if (ret  != 1)
+		return NULL;
+
+	if (jd->needs_bswap) {
+		prefix->id   	   = bswap_32(prefix->id);
+		prefix->total_size = bswap_32(prefix->total_size);
+		prefix->timestamp  = bswap_64(prefix->timestamp);
+	}
+	id   = prefix->id;
+	size = prefix->total_size;
+
+	bs = (size_t)size;
+	if (bs < sizeof(*prefix))
+		return NULL;
+
+	if (id >= JIT_CODE_MAX) {
+		pr_warning("next_entry: unknown prefix %d, skipping\n", id);
+		return NULL;
+	}
+	if (bs > jd->bufsize) {
+		void *n;
+		n = realloc(jd->buf, bs);
+		if (!n)
+			return NULL;
+		jd->buf = n;
+		jd->bufsize = bs;
+	}
+
+	addr = ((void *)jd->buf) + sizeof(*prefix);
+
+	ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
+	if (ret != 1)
+		return NULL;
+
+	jr = (union jr_entry *)jd->buf;
+
+	switch(id) {
+	case JIT_CODE_DEBUG_INFO:
+		if (jd->needs_bswap) {
+			uint64_t n;
+			jr->info.code_addr = bswap_64(jr->info.code_addr);
+			jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
+			for (n = 0 ; n < jr->info.nr_entry; n++) {
+				jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
+				jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
+				jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
+			}
+		}
+		break;
+	case JIT_CODE_CLOSE:
+		break;
+	case JIT_CODE_LOAD:
+		if (jd->needs_bswap) {
+			jr->load.pid       = bswap_32(jr->load.pid);
+			jr->load.tid       = bswap_32(jr->load.tid);
+			jr->load.vma       = bswap_64(jr->load.vma);
+			jr->load.code_addr = bswap_64(jr->load.code_addr);
+			jr->load.code_size = bswap_64(jr->load.code_size);
+			jr->load.code_index= bswap_64(jr->load.code_index);
+		}
+		jd->code_load_count++;
+		break;
+	case JIT_CODE_MOVE:
+		if (jd->needs_bswap) {
+			jr->move.pid           = bswap_32(jr->move.pid);
+			jr->move.tid           = bswap_32(jr->move.tid);
+			jr->move.vma           = bswap_64(jr->move.vma);
+			jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
+			jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
+			jr->move.code_size     = bswap_64(jr->move.code_size);
+			jr->move.code_index    = bswap_64(jr->move.code_index);
+		}
+		break;
+	case JIT_CODE_MAX:
+	default:
+		return NULL;
+	}
+	return jr;
+}
+
+static int
+jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
+{
+	ssize_t size;
+
+	size = perf_data_file__write(jd->output, event, event->header.size);
+	if (size < 0)
+		return -1;
+
+	jd->bytes_written += size;
+	return 0;
+}
+
+static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+	struct perf_sample sample;
+	union perf_event *event;
+	struct perf_tool *tool = jd->session->tool;
+	uint64_t code, addr;
+	uintptr_t uaddr;
+	char *filename;
+	struct stat st;
+	size_t size;
+	u16 idr_size;
+	const char *sym;
+	uint32_t count;
+	int ret, csize;
+	pid_t pid, tid;
+	struct {
+		u32 pid, tid;
+		u64 time;
+	} *id;
+
+	pid   = jr->load.pid;
+	tid   = jr->load.tid;
+	csize = jr->load.code_size;
+	addr  = jr->load.code_addr;
+	sym   = (void *)((unsigned long)jr + sizeof(jr->load));
+	code  = (unsigned long)jr + jr->load.p.total_size - csize;
+	count = jr->load.code_index;
+	idr_size = jd->machine->id_hdr_size;
+
+	event = calloc(1, sizeof(*event) + idr_size);
+	if (!event)
+		return -1;
+
+	filename = event->mmap2.filename;
+	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%u.so",
+			jd->dir,
+			pid,
+			count);
+
+	size++; /* for \0 */
+
+	size = PERF_ALIGN(size, sizeof(u64));
+	uaddr = (uintptr_t)code;
+	ret = jit_emit_elf(filename, sym, addr, (const void *)uaddr, csize);
+
+	if (jd->debug_data && jd->nr_debug_entries) {
+		free(jd->debug_data);
+		jd->debug_data = NULL;
+		jd->nr_debug_entries = 0;
+	}
+
+	if (ret) {
+		free(event);
+		return -1;
+	}
+	if (stat(filename, &st))
+		memset(&st, 0, sizeof(stat));
+
+	event->mmap2.header.type = PERF_RECORD_MMAP2;
+	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
+	event->mmap2.header.size = (sizeof(event->mmap2) -
+			(sizeof(event->mmap2.filename) - size) + idr_size);
+
+	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
+	event->mmap2.start = addr;
+	event->mmap2.len   = csize;
+	event->mmap2.pid   = pid;
+	event->mmap2.tid   = tid;
+	event->mmap2.ino   = st.st_ino;
+	event->mmap2.maj   = major(st.st_dev);
+	event->mmap2.min   = minor(st.st_dev);
+	event->mmap2.prot  = st.st_mode;
+	event->mmap2.flags = MAP_SHARED;
+	event->mmap2.ino_generation = 1;
+
+	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
+	if (jd->sample_type & PERF_SAMPLE_TID) {
+		id->pid  = pid;
+		id->tid  = tid;
+	}
+	if (jd->sample_type & PERF_SAMPLE_TIME)
+		id->time = jr->load.p.timestamp;
+
+	/*
+	 * create pseudo sample to induce dso hit increment
+	 * use first address as sample address
+	 */
+	memset(&sample, 0, sizeof(sample));
+	sample.pid  = pid;
+	sample.tid  = tid;
+	sample.time = id->time;
+	sample.ip   = addr;
+
+	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
+	if (ret)
+		return ret;
+
+	ret = jit_inject_event(jd, event);
+	/*
+	 * mark dso as use to generate buildid in the header
+	 */
+	if (!ret)
+		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
+
+	return ret;
+}
+
+static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+	struct perf_sample sample;
+	union perf_event *event;
+	struct perf_tool *tool = jd->session->tool;
+	char *filename;
+	size_t size;
+	struct stat st;
+	u16 idr_size;
+	int ret;
+	pid_t pid, tid;
+	struct {
+		u32 pid, tid;
+		u64 time;
+	} *id;
+
+	pid = jr->move.pid;
+	tid =  jr->move.tid;
+	idr_size = jd->machine->id_hdr_size;
+
+	/*
+	 * +16 to account for sample_id_all (hack)
+	 */
+	event = calloc(1, sizeof(*event) + 16);
+	if (!event)
+		return -1;
+
+	filename = event->mmap2.filename;
+	size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%"PRIu64,
+	         jd->dir,
+	         pid,
+		 jr->move.code_index);
+
+	size++; /* for \0 */
+
+	if (stat(filename, &st))
+		memset(&st, 0, sizeof(stat));
+
+	size = PERF_ALIGN(size, sizeof(u64));
+
+	event->mmap2.header.type = PERF_RECORD_MMAP2;
+	event->mmap2.header.misc = PERF_RECORD_MISC_USER;
+	event->mmap2.header.size = (sizeof(event->mmap2) -
+			(sizeof(event->mmap2.filename) - size) + idr_size);
+	event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
+	event->mmap2.start = jr->move.new_code_addr;
+	event->mmap2.len   = jr->move.code_size;
+	event->mmap2.pid   = pid;
+	event->mmap2.tid   = tid;
+	event->mmap2.ino   = st.st_ino;
+	event->mmap2.maj   = major(st.st_dev);
+	event->mmap2.min   = minor(st.st_dev);
+	event->mmap2.prot  = st.st_mode;
+	event->mmap2.flags = MAP_SHARED;
+	event->mmap2.ino_generation = 1;
+
+	id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
+	if (jd->sample_type & PERF_SAMPLE_TID) {
+		id->pid  = pid;
+		id->tid  = tid;
+	}
+	if (jd->sample_type & PERF_SAMPLE_TIME)
+		id->time = jr->load.p.timestamp;
+
+	/*
+	 * create pseudo sample to induce dso hit increment
+	 * use first address as sample address
+	 */
+	memset(&sample, 0, sizeof(sample));
+	sample.pid  = pid;
+	sample.tid  = tid;
+	sample.time = id->time;
+	sample.ip   = jr->move.new_code_addr;
+
+	ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
+	if (ret)
+		return ret;
+
+	ret = jit_inject_event(jd, event);
+	if (!ret)
+		build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
+
+	return ret;
+}
+
+static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
+{
+	void *data;
+	size_t sz;
+
+	if (!(jd && jr))
+		return -1;
+
+	sz  = jr->prefix.total_size - sizeof(jr->info);
+	data = malloc(sz);
+	if (!data)
+		return -1;
+
+	memcpy(data, &jr->info.entries, sz);
+
+	jd->debug_data       = data;
+
+	/*
+	 * we must use nr_entry instead of size here because
+	 * we cannot distinguish actual entry from padding otherwise
+	 */
+	jd->nr_debug_entries = jr->info.nr_entry;
+
+	return 0;
+}
+
+static int
+jit_process_dump(struct jit_buf_desc *jd)
+{
+	union jr_entry *jr;
+	int ret;
+
+	while ((jr = jit_get_next_entry(jd))) {
+		switch(jr->prefix.id) {
+		case JIT_CODE_LOAD:
+			ret = jit_repipe_code_load(jd, jr);
+			break;
+		case JIT_CODE_MOVE:
+			ret = jit_repipe_code_move(jd, jr);
+			break;
+		case JIT_CODE_DEBUG_INFO:
+			ret = jit_repipe_debug_info(jd, jr);
+			break;
+		default:
+			ret = 0;
+			continue;
+		}
+	}
+	return ret;
+}
+
+static int
+jit_inject(struct jit_buf_desc *jd, char *path)
+{
+	int ret;
+
+	if (verbose > 0)
+		fprintf(stderr, "injecting: %s\n", path);
+
+	ret = jit_open(jd, path);
+	if (ret)
+		return -1;
+
+	ret = jit_process_dump(jd);
+
+	jit_close(jd);
+
+	if (verbose > 0)
+		fprintf(stderr, "injected: %s (%d)\n", path, ret);
+
+	return 0;
+}
+
+/*
+ * File must be with pattern .../jit-XXXX.dump
+ * where XXXX is the PID of the process which did the mmap()
+ * as captured in the RECORD_MMAP record
+ */
+static int
+jit_detect(char *mmap_name, pid_t pid)
+ {
+	char *p;
+	char *end = NULL;
+	pid_t pid2;
+
+	if (verbose > 2)
+		fprintf(stderr, "jit marker trying : %s\n", mmap_name);
+	/*
+	 * get file name
+	 */
+	p = strrchr(mmap_name, '/');
+	if (!p)
+		return -1;
+
+	/*
+	 * match prefix
+	 */
+	if (strncmp(p, "/jit-", 5))
+		return -1;
+
+	/*
+	 * skip prefix
+	 */
+	p += 5;
+
+	/*
+	 * must be followed by a pid
+	 */
+	if (!isdigit(*p))
+		return -1;
+
+	pid2 = (int)strtol(p, &end, 10);
+	if (!end)
+		return -1;
+
+	/*
+	 * pid does not match mmap pid
+	 * pid==0 in system-wide mode (synthesized)
+	 */
+	if (pid && pid2 != pid)
+		return -1;
+	/*
+	 * validate suffix
+	 */
+	if (strcmp(end, ".dump"))
+		return -1;
+
+	if (verbose > 0)
+		fprintf(stderr, "jit marker found: %s\n", mmap_name);
+
+	return 0;
+}
+
+int
+jit_process(struct perf_session *session,
+	    struct perf_data_file *output,
+	    struct machine *machine,
+	    char *filename,
+	    pid_t pid,
+	    u64 *nbytes)
+{
+	struct perf_evsel *first;
+	struct jit_buf_desc jd;
+	int ret;
+
+	/*
+	 * first, detect marker mmap (i.e., the jitdump mmap)
+	 */
+	if (jit_detect(filename, pid))
+		return -1;
+
+	memset(&jd, 0, sizeof(jd));
+
+	jd.session = session;
+	jd.output  = output;
+	jd.machine = machine;
+
+	/*
+	 * track sample_type to compute id_all layout
+	 * perf sets the same sample type to all events as of now
+	 */
+	first = perf_evlist__first(session->evlist);
+	jd.sample_type = first->attr.sample_type;
+
+	*nbytes = 0;
+
+	ret = jit_inject(&jd, filename);
+	if (!ret)
+		*nbytes = jd.bytes_written;
+
+	return ret;
+}

tools/perf/util/jitdump.h

+/*
+ * jitdump.h: jitted code info encapsulation file format
+ *
+ * Adapted from OProfile GPLv2 support jidump.h:
+ * Copyright 2007 OProfile authors
+ * Jens Wilke
+ * Daniel Hansel
+ * Copyright IBM Corporation 2007
+ */
+#ifndef JITDUMP_H
+#define JITDUMP_H
+
+#include <sys/time.h>
+#include <time.h>
+#include <stdint.h>
+
+/* JiTD */
+#define JITHEADER_MAGIC		0x4A695444
+#define JITHEADER_MAGIC_SW	0x4454694A
+
+#define PADDING_8ALIGNED(x) ((((x) + 7) & 7) ^ 7)
+
+#define JITHEADER_VERSION 1
+
+enum jitdump_flags_bits {
+	JITDUMP_FLAGS_MAX_BIT,
+};
+
+#define JITDUMP_FLAGS_RESERVED (JITDUMP_FLAGS_MAX_BIT < 64 ? \
+				(~((1ULL << JITDUMP_FLAGS_MAX_BIT) - 1)) : 0)
+
+struct jitheader {
+	uint32_t magic;		/* characters "jItD" */
+	uint32_t version;	/* header version */
+	uint32_t total_size;	/* total size of header */
+	uint32_t elf_mach;	/* elf mach target */
+	uint32_t pad1;		/* reserved */
+	uint32_t pid;		/* JIT process id */
+	uint64_t timestamp;	/* timestamp */
+	uint64_t flags;		/* flags */
+};
+
+enum jit_record_type {
+	JIT_CODE_LOAD		= 0,
+        JIT_CODE_MOVE           = 1,
+	JIT_CODE_DEBUG_INFO	= 2,
+	JIT_CODE_CLOSE		= 3,
+
+	JIT_CODE_MAX,
+};
+
+/* record prefix (mandatory in each record) */
+struct jr_prefix {
+	uint32_t id;
+	uint32_t total_size;
+	uint64_t timestamp;
+};
+
+struct jr_code_load {
+	struct jr_prefix p;
+
+	uint32_t pid;
+	uint32_t tid;
+	uint64_t vma;
+	uint64_t code_addr;
+	uint64_t code_size;
+	uint64_t code_index;
+};
+
+struct jr_code_close {
+	struct jr_prefix p;
+};
+
+struct jr_code_move {
+	struct jr_prefix p;
+
+	uint32_t pid;
+	uint32_t tid;
+	uint64_t vma;
+	uint64_t old_code_addr;
+	uint64_t new_code_addr;
+	uint64_t code_size;
+	uint64_t code_index;
+};
+
+struct debug_entry {
+	uint64_t addr;
+	int lineno;	    /* source line number starting at 1 */
+	int discrim;	    /* column discriminator, 0 is default */
+	const char name[0]; /* null terminated filename, \xff\0 if same as previous entry */
+};
+
+struct jr_code_debug_info {
+	struct jr_prefix p;
+
+	uint64_t code_addr;
+	uint64_t nr_entry;
+	struct debug_entry entries[0];
+};
+
+union jr_entry {
+        struct jr_code_debug_info info;
+        struct jr_code_close close;
+        struct jr_code_load load;
+        struct jr_code_move move;
+        struct jr_prefix prefix;
+};
+
+static inline struct debug_entry *
+debug_entry_next(struct debug_entry *ent)
+{
+	void *a = ent + 1;
+	size_t l = strlen(ent->name) + 1;
+	return a + l;
+}
+
+static inline char *
+debug_entry_file(struct debug_entry *ent)
+{
+	void *a = ent + 1;
+	return a;
+}
+
+#endif /* !JITDUMP_H */