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Diffstat (limited to 'tools/perf/jvmti/jvmti_agent.c')
-rw-r--r--tools/perf/jvmti/jvmti_agent.c465
1 files changed, 465 insertions, 0 deletions
diff --git a/tools/perf/jvmti/jvmti_agent.c b/tools/perf/jvmti/jvmti_agent.c
new file mode 100644
index 000000000000..6461e02ab940
--- /dev/null
+++ b/tools/perf/jvmti/jvmti_agent.c
@@ -0,0 +1,465 @@
+/*
+ * 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;
+
+/*
+ * padding buffer
+ */
+static const char pad_bytes[7];
+
+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;
+ int m = -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 */
+ if (id[0] != 0x7f || id[1] != 'E' || id[2] != 'L' || id[3] != 'F')
+ goto error;
+
+ sret = read(fd, &info, sizeof(info));
+ if (sret != sizeof(info))
+ goto error;
+
+ m = info.e_machine;
+ if (m < 0)
+ m = 0; /* ELF EM_NONE */
+
+ hdr->elf_mach = m;
+ ret = 0;
+error:
+ close(fd);
+ return ret;
+}
+
+#define NSEC_PER_SEC 1000000000
+static int perf_clk_id = CLOCK_MONOTONIC;
+
+static inline uint64_t
+timespec_to_ns(const struct timespec *ts)
+{
+ return ((uint64_t) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec;
+}
+
+static inline uint64_t
+perf_get_timestamp(void)
+{
+ struct timespec ts;
+ int ret;
+
+ ret = clock_gettime(perf_clk_id, &ts);
+ if (ret)
+ return 0;
+
+ return timespec_to_ns(&ts);
+}
+
+static int
+debug_cache_init(void)
+{
+ char str[32];
+ char *base, *p;
+ struct tm tm;
+ time_t t;
+ int ret;
+
+ time(&t);
+ localtime_r(&t, &tm);
+
+ base = getenv("JITDUMPDIR");
+ if (!base)
+ base = getenv("HOME");
+ if (!base)
+ base = ".";
+
+ strftime(str, sizeof(str), JIT_LANG"-jit-%Y%m%d", &tm);
+
+ snprintf(jit_path, PATH_MAX - 1, "%s/.debug/", base);
+
+ ret = mkdir(jit_path, 0755);
+ if (ret == -1) {
+ if (errno != EEXIST) {
+ warn("jvmti: cannot create jit cache dir %s", jit_path);
+ return -1;
+ }
+ }
+
+ snprintf(jit_path, PATH_MAX - 1, "%s/.debug/jit", base);
+ ret = mkdir(jit_path, 0755);
+ if (ret == -1) {
+ if (errno != EEXIST) {
+ warn("cannot create jit cache dir %s", jit_path);
+ return -1;
+ }
+ }
+
+ snprintf(jit_path, PATH_MAX - 1, "%s/.debug/jit/%s.XXXXXXXX", base, str);
+
+ p = mkdtemp(jit_path);
+ if (p != jit_path) {
+ warn("cannot create jit cache dir %s", jit_path);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int
+perf_open_marker_file(int fd)
+{
+ long pgsz;
+
+ pgsz = sysconf(_SC_PAGESIZE);
+ if (pgsz == -1)
+ return -1;
+
+ /*
+ * we mmap the jitdump to create an MMAP RECORD in perf.data file.
+ * The mmap is captured either live (perf record running when we mmap)
+ * or in deferred mode, via /proc/PID/maps
+ * the MMAP record is used as a marker of a jitdump file for more meta
+ * data info about the jitted code. Perf report/annotate detect this
+ * special filename and process the jitdump file.
+ *
+ * mapping must be PROT_EXEC to ensure it is captured by perf record
+ * even when not using -d option
+ */
+ marker_addr = mmap(NULL, pgsz, PROT_READ|PROT_EXEC, MAP_PRIVATE, fd, 0);
+ return (marker_addr == MAP_FAILED) ? -1 : 0;
+}
+
+static void
+perf_close_marker_file(void)
+{
+ long pgsz;
+
+ if (!marker_addr)
+ return;
+
+ pgsz = sysconf(_SC_PAGESIZE);
+ if (pgsz == -1)
+ return;
+
+ munmap(marker_addr, pgsz);
+}
+
+void *jvmti_open(void)
+{
+ int pad_cnt;
+ char dump_path[PATH_MAX];
+ struct jitheader header;
+ int fd;
+ FILE *fp;
+
+ /*
+ * check if clockid is supported
+ */
+ if (!perf_get_timestamp())
+ warnx("jvmti: kernel does not support %d clock id", perf_clk_id);
+
+ memset(&header, 0, sizeof(header));
+
+ debug_cache_init();
+
+ /*
+ * jitdump file name
+ */
+ snprintf(dump_path, PATH_MAX, "%s/jit-%i.dump", jit_path, getpid());
+
+ fd = open(dump_path, O_CREAT|O_TRUNC|O_RDWR, 0666);
+ if (fd == -1)
+ return NULL;
+
+ /*
+ * create perf.data maker for the jitdump file
+ */
+ if (perf_open_marker_file(fd)) {
+ warnx("jvmti: failed to create marker file");
+ return NULL;
+ }
+
+ fp = fdopen(fd, "w+");
+ if (!fp) {
+ warn("jvmti: cannot create %s", dump_path);
+ close(fd);
+ goto error;
+ }
+
+ warnx("jvmti: jitdump in %s", dump_path);
+
+ if (get_e_machine(&header)) {
+ warn("get_e_machine failed\n");
+ goto error;
+ }
+
+ header.magic = JITHEADER_MAGIC;
+ header.version = JITHEADER_VERSION;
+ header.total_size = sizeof(header);
+ header.pid = getpid();
+
+ /* calculate amount of padding '\0' */
+ pad_cnt = PADDING_8ALIGNED(header.total_size);
+ header.total_size += pad_cnt;
+
+ header.timestamp = perf_get_timestamp();
+
+ if (!fwrite(&header, sizeof(header), 1, fp)) {
+ warn("jvmti: cannot write dumpfile header");
+ goto error;
+ }
+
+ /* write padding '\0' if necessary */
+ if (pad_cnt && !fwrite(pad_bytes, pad_cnt, 1, fp)) {
+ warn("jvmti: cannot write dumpfile header padding");
+ goto error;
+ }
+
+ return fp;
+error:
+ fclose(fp);
+ return NULL;
+}
+
+int
+jvmti_close(void *agent)
+{
+ struct jr_code_close rec;
+ FILE *fp = agent;
+
+ if (!fp) {
+ warnx("jvmti: incalid fd in close_agent");
+ return -1;
+ }
+
+ rec.p.id = JIT_CODE_CLOSE;
+ rec.p.total_size = sizeof(rec);
+
+ rec.p.timestamp = perf_get_timestamp();
+
+ if (!fwrite(&rec, sizeof(rec), 1, fp))
+ return -1;
+
+ fclose(fp);
+
+ fp = NULL;
+
+ perf_close_marker_file();
+
+ return 0;
+}
+
+int
+jvmti_write_code(void *agent, char const *sym,
+ uint64_t vma, void const *code, unsigned int const size)
+{
+ static int code_generation = 1;
+ struct jr_code_load rec;
+ size_t sym_len;
+ size_t padding_count;
+ FILE *fp = agent;
+ int ret = -1;
+
+ /* don't care about 0 length function, no samples */
+ if (size == 0)
+ return 0;
+
+ if (!fp) {
+ warnx("jvmti: invalid fd in write_native_code");
+ return -1;
+ }
+
+ sym_len = strlen(sym) + 1;
+
+ rec.p.id = JIT_CODE_LOAD;
+ rec.p.total_size = sizeof(rec) + sym_len;
+ padding_count = PADDING_8ALIGNED(rec.p.total_size);
+ rec.p. total_size += padding_count;
+ rec.p.timestamp = perf_get_timestamp();
+
+ rec.code_size = size;
+ rec.vma = vma;
+ rec.code_addr = vma;
+ rec.pid = getpid();
+ rec.tid = gettid();
+
+ if (code)
+ rec.p.total_size += size;
+
+ /*
+ * If JVM is multi-threaded, nultiple concurrent calls to agent
+ * may be possible, so protect file writes
+ */
+ flockfile(fp);
+
+ /*
+ * get code index inside lock to avoid race condition
+ */
+ rec.code_index = code_generation++;
+
+ ret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
+ fwrite_unlocked(sym, sym_len, 1, fp);
+
+ if (padding_count)
+ fwrite_unlocked(pad_bytes, padding_count, 1, fp);
+
+ if (code)
+ fwrite_unlocked(code, size, 1, fp);
+
+ funlockfile(fp);
+
+ ret = 0;
+
+ return ret;
+}
+
+int
+jvmti_write_debug_info(void *agent, uint64_t code, const char *file,
+ jvmti_line_info_t *li, int nr_lines)
+{
+ struct jr_code_debug_info rec;
+ size_t sret, len, size, flen;
+ size_t padding_count;
+ uint64_t addr;
+ const char *fn = file;
+ FILE *fp = agent;
+ int i;
+
+ /*
+ * no entry to write
+ */
+ if (!nr_lines)
+ return 0;
+
+ if (!fp) {
+ warnx("jvmti: invalid fd in write_debug_info");
+ return -1;
+ }
+
+ flen = strlen(file) + 1;
+
+ rec.p.id = JIT_CODE_DEBUG_INFO;
+ size = sizeof(rec);
+ rec.p.timestamp = perf_get_timestamp();
+ rec.code_addr = (uint64_t)(uintptr_t)code;
+ rec.nr_entry = nr_lines;
+
+ /*
+ * on disk source line info layout:
+ * uint64_t : addr
+ * int : line number
+ * int : column discriminator
+ * file[] : source file name
+ * padding : pad to multiple of 8 bytes
+ */
+ size += nr_lines * sizeof(struct debug_entry);
+ size += flen * nr_lines;
+ /*
+ * pad to 8 bytes
+ */
+ padding_count = PADDING_8ALIGNED(size);
+
+ rec.p.total_size = size + padding_count;
+
+ /*
+ * If JVM is multi-threaded, nultiple concurrent calls to agent
+ * may be possible, so protect file writes
+ */
+ flockfile(fp);
+
+ sret = fwrite_unlocked(&rec, sizeof(rec), 1, fp);
+ if (sret != 1)
+ goto error;
+
+ for (i = 0; i < nr_lines; i++) {
+
+ addr = (uint64_t)li[i].pc;
+ len = sizeof(addr);
+ sret = fwrite_unlocked(&addr, len, 1, fp);
+ if (sret != 1)
+ goto error;
+
+ len = sizeof(li[0].line_number);
+ sret = fwrite_unlocked(&li[i].line_number, len, 1, fp);
+ if (sret != 1)
+ goto error;
+
+ len = sizeof(li[0].discrim);
+ sret = fwrite_unlocked(&li[i].discrim, len, 1, fp);
+ if (sret != 1)
+ goto error;
+
+ sret = fwrite_unlocked(fn, flen, 1, fp);
+ if (sret != 1)
+ goto error;
+ }
+ if (padding_count)
+ sret = fwrite_unlocked(pad_bytes, padding_count, 1, fp);
+ if (sret != 1)
+ goto error;
+
+ funlockfile(fp);
+ return 0;
+error:
+ funlockfile(fp);
+ return -1;
+}