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-rw-r--r--tools/perf/builtin-record.c544
1 files changed, 544 insertions, 0 deletions
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
new file mode 100644
index 000000000000..aeab9c4b15e4
--- /dev/null
+++ b/tools/perf/builtin-record.c
@@ -0,0 +1,544 @@
+/*
+ * builtin-record.c
+ *
+ * Builtin record command: Record the profile of a workload
+ * (or a CPU, or a PID) into the perf.data output file - for
+ * later analysis via perf report.
+ */
+#include "builtin.h"
+
+#include "perf.h"
+
+#include "util/util.h"
+#include "util/parse-options.h"
+#include "util/parse-events.h"
+#include "util/string.h"
+
+#include <unistd.h>
+#include <sched.h>
+
+#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a)-1)
+#define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask))
+
+static int fd[MAX_NR_CPUS][MAX_COUNTERS];
+
+static long default_interval = 100000;
+
+static int nr_cpus = 0;
+static unsigned int page_size;
+static unsigned int mmap_pages = 128;
+static int freq = 0;
+static int output;
+static const char *output_name = "perf.data";
+static int group = 0;
+static unsigned int realtime_prio = 0;
+static int system_wide = 0;
+static pid_t target_pid = -1;
+static int inherit = 1;
+static int force = 0;
+static int append_file = 0;
+
+static long samples;
+static struct timeval last_read;
+static struct timeval this_read;
+
+static __u64 bytes_written;
+
+static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
+
+static int nr_poll;
+static int nr_cpu;
+
+struct mmap_event {
+ struct perf_event_header header;
+ __u32 pid;
+ __u32 tid;
+ __u64 start;
+ __u64 len;
+ __u64 pgoff;
+ char filename[PATH_MAX];
+};
+
+struct comm_event {
+ struct perf_event_header header;
+ __u32 pid;
+ __u32 tid;
+ char comm[16];
+};
+
+
+struct mmap_data {
+ int counter;
+ void *base;
+ unsigned int mask;
+ unsigned int prev;
+};
+
+static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
+
+static unsigned int mmap_read_head(struct mmap_data *md)
+{
+ struct perf_counter_mmap_page *pc = md->base;
+ int head;
+
+ head = pc->data_head;
+ rmb();
+
+ return head;
+}
+
+static void mmap_read(struct mmap_data *md)
+{
+ unsigned int head = mmap_read_head(md);
+ unsigned int old = md->prev;
+ unsigned char *data = md->base + page_size;
+ unsigned long size;
+ void *buf;
+ int diff;
+
+ gettimeofday(&this_read, NULL);
+
+ /*
+ * If we're further behind than half the buffer, there's a chance
+ * the writer will bite our tail and mess up the samples under us.
+ *
+ * If we somehow ended up ahead of the head, we got messed up.
+ *
+ * In either case, truncate and restart at head.
+ */
+ diff = head - old;
+ if (diff > md->mask / 2 || diff < 0) {
+ struct timeval iv;
+ unsigned long msecs;
+
+ timersub(&this_read, &last_read, &iv);
+ msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
+
+ fprintf(stderr, "WARNING: failed to keep up with mmap data."
+ " Last read %lu msecs ago.\n", msecs);
+
+ /*
+ * head points to a known good entry, start there.
+ */
+ old = head;
+ }
+
+ last_read = this_read;
+
+ if (old != head)
+ samples++;
+
+ size = head - old;
+
+ if ((old & md->mask) + size != (head & md->mask)) {
+ buf = &data[old & md->mask];
+ size = md->mask + 1 - (old & md->mask);
+ old += size;
+
+ while (size) {
+ int ret = write(output, buf, size);
+
+ if (ret < 0)
+ die("failed to write");
+
+ size -= ret;
+ buf += ret;
+
+ bytes_written += ret;
+ }
+ }
+
+ buf = &data[old & md->mask];
+ size = head - old;
+ old += size;
+
+ while (size) {
+ int ret = write(output, buf, size);
+
+ if (ret < 0)
+ die("failed to write");
+
+ size -= ret;
+ buf += ret;
+
+ bytes_written += ret;
+ }
+
+ md->prev = old;
+}
+
+static volatile int done = 0;
+
+static void sig_handler(int sig)
+{
+ done = 1;
+}
+
+static void pid_synthesize_comm_event(pid_t pid, int full)
+{
+ struct comm_event comm_ev;
+ char filename[PATH_MAX];
+ char bf[BUFSIZ];
+ int fd, ret;
+ size_t size;
+ char *field, *sep;
+ DIR *tasks;
+ struct dirent dirent, *next;
+
+ snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);
+
+ fd = open(filename, O_RDONLY);
+ if (fd < 0) {
+ fprintf(stderr, "couldn't open %s\n", filename);
+ exit(EXIT_FAILURE);
+ }
+ if (read(fd, bf, sizeof(bf)) < 0) {
+ fprintf(stderr, "couldn't read %s\n", filename);
+ exit(EXIT_FAILURE);
+ }
+ close(fd);
+
+ /* 9027 (cat) R 6747 9027 6747 34816 9027 ... */
+ memset(&comm_ev, 0, sizeof(comm_ev));
+ field = strchr(bf, '(');
+ if (field == NULL)
+ goto out_failure;
+ sep = strchr(++field, ')');
+ if (sep == NULL)
+ goto out_failure;
+ size = sep - field;
+ memcpy(comm_ev.comm, field, size++);
+
+ comm_ev.pid = pid;
+ comm_ev.header.type = PERF_EVENT_COMM;
+ size = ALIGN(size, sizeof(uint64_t));
+ comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
+
+ if (!full) {
+ comm_ev.tid = pid;
+
+ ret = write(output, &comm_ev, comm_ev.header.size);
+ if (ret < 0) {
+ perror("failed to write");
+ exit(-1);
+ }
+ return;
+ }
+
+ snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
+
+ tasks = opendir(filename);
+ while (!readdir_r(tasks, &dirent, &next) && next) {
+ char *end;
+ pid = strtol(dirent.d_name, &end, 10);
+ if (*end)
+ continue;
+
+ comm_ev.tid = pid;
+
+ ret = write(output, &comm_ev, comm_ev.header.size);
+ if (ret < 0) {
+ perror("failed to write");
+ exit(-1);
+ }
+ }
+ closedir(tasks);
+ return;
+
+out_failure:
+ fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
+ filename);
+ exit(EXIT_FAILURE);
+}
+
+static void pid_synthesize_mmap_samples(pid_t pid)
+{
+ char filename[PATH_MAX];
+ FILE *fp;
+
+ snprintf(filename, sizeof(filename), "/proc/%d/maps", pid);
+
+ fp = fopen(filename, "r");
+ if (fp == NULL) {
+ fprintf(stderr, "couldn't open %s\n", filename);
+ exit(EXIT_FAILURE);
+ }
+ while (1) {
+ char bf[BUFSIZ], *pbf = bf;
+ struct mmap_event mmap_ev = {
+ .header.type = PERF_EVENT_MMAP,
+ };
+ int n;
+ size_t size;
+ if (fgets(bf, sizeof(bf), fp) == NULL)
+ break;
+
+ /* 00400000-0040c000 r-xp 00000000 fd:01 41038 /bin/cat */
+ n = hex2u64(pbf, &mmap_ev.start);
+ if (n < 0)
+ continue;
+ pbf += n + 1;
+ n = hex2u64(pbf, &mmap_ev.len);
+ if (n < 0)
+ continue;
+ pbf += n + 3;
+ if (*pbf == 'x') { /* vm_exec */
+ char *execname = strrchr(bf, ' ');
+
+ if (execname == NULL || execname[1] != '/')
+ continue;
+
+ execname += 1;
+ size = strlen(execname);
+ execname[size - 1] = '\0'; /* Remove \n */
+ memcpy(mmap_ev.filename, execname, size);
+ size = ALIGN(size, sizeof(uint64_t));
+ mmap_ev.len -= mmap_ev.start;
+ mmap_ev.header.size = (sizeof(mmap_ev) -
+ (sizeof(mmap_ev.filename) - size));
+ mmap_ev.pid = pid;
+ mmap_ev.tid = pid;
+
+ if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
+ perror("failed to write");
+ exit(-1);
+ }
+ }
+ }
+
+ fclose(fp);
+}
+
+static void synthesize_samples(void)
+{
+ DIR *proc;
+ struct dirent dirent, *next;
+
+ proc = opendir("/proc");
+
+ while (!readdir_r(proc, &dirent, &next) && next) {
+ char *end;
+ pid_t pid;
+
+ pid = strtol(dirent.d_name, &end, 10);
+ if (*end) /* only interested in proper numerical dirents */
+ continue;
+
+ pid_synthesize_comm_event(pid, 1);
+ pid_synthesize_mmap_samples(pid);
+ }
+
+ closedir(proc);
+}
+
+static int group_fd;
+
+static void create_counter(int counter, int cpu, pid_t pid)
+{
+ struct perf_counter_attr *attr = attrs + counter;
+ int track = 1;
+
+ attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID | PERF_SAMPLE_PERIOD;
+ if (freq) {
+ attr->freq = 1;
+ attr->sample_freq = freq;
+ }
+ attr->mmap = track;
+ attr->comm = track;
+ attr->inherit = (cpu < 0) && inherit;
+
+ track = 0; /* only the first counter needs these */
+
+ fd[nr_cpu][counter] = sys_perf_counter_open(attr, pid, cpu, group_fd, 0);
+
+ if (fd[nr_cpu][counter] < 0) {
+ int err = errno;
+
+ error("syscall returned with %d (%s)\n",
+ fd[nr_cpu][counter], strerror(err));
+ if (err == EPERM)
+ printf("Are you root?\n");
+ exit(-1);
+ }
+ assert(fd[nr_cpu][counter] >= 0);
+ fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
+
+ /*
+ * First counter acts as the group leader:
+ */
+ if (group && group_fd == -1)
+ group_fd = fd[nr_cpu][counter];
+
+ event_array[nr_poll].fd = fd[nr_cpu][counter];
+ event_array[nr_poll].events = POLLIN;
+ nr_poll++;
+
+ mmap_array[nr_cpu][counter].counter = counter;
+ mmap_array[nr_cpu][counter].prev = 0;
+ mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
+ mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
+ PROT_READ, MAP_SHARED, fd[nr_cpu][counter], 0);
+ if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
+ error("failed to mmap with %d (%s)\n", errno, strerror(errno));
+ exit(-1);
+ }
+}
+
+static void open_counters(int cpu, pid_t pid)
+{
+ int counter;
+
+ if (pid > 0) {
+ pid_synthesize_comm_event(pid, 0);
+ pid_synthesize_mmap_samples(pid);
+ }
+
+ group_fd = -1;
+ for (counter = 0; counter < nr_counters; counter++)
+ create_counter(counter, cpu, pid);
+
+ nr_cpu++;
+}
+
+static int __cmd_record(int argc, const char **argv)
+{
+ int i, counter;
+ struct stat st;
+ pid_t pid;
+ int flags;
+ int ret;
+
+ page_size = sysconf(_SC_PAGE_SIZE);
+ nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+ assert(nr_cpus <= MAX_NR_CPUS);
+ assert(nr_cpus >= 0);
+
+ if (!stat(output_name, &st) && !force && !append_file) {
+ fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
+ output_name);
+ exit(-1);
+ }
+
+ flags = O_CREAT|O_RDWR;
+ if (append_file)
+ flags |= O_APPEND;
+ else
+ flags |= O_TRUNC;
+
+ output = open(output_name, flags, S_IRUSR|S_IWUSR);
+ if (output < 0) {
+ perror("failed to create output file");
+ exit(-1);
+ }
+
+ if (!system_wide) {
+ open_counters(-1, target_pid != -1 ? target_pid : getpid());
+ } else for (i = 0; i < nr_cpus; i++)
+ open_counters(i, target_pid);
+
+ signal(SIGCHLD, sig_handler);
+ signal(SIGINT, sig_handler);
+
+ if (target_pid == -1 && argc) {
+ pid = fork();
+ if (pid < 0)
+ perror("failed to fork");
+
+ if (!pid) {
+ if (execvp(argv[0], (char **)argv)) {
+ perror(argv[0]);
+ exit(-1);
+ }
+ }
+ }
+
+ if (realtime_prio) {
+ struct sched_param param;
+
+ param.sched_priority = realtime_prio;
+ if (sched_setscheduler(0, SCHED_FIFO, &param)) {
+ printf("Could not set realtime priority.\n");
+ exit(-1);
+ }
+ }
+
+ if (system_wide)
+ synthesize_samples();
+
+ while (!done) {
+ int hits = samples;
+
+ for (i = 0; i < nr_cpu; i++) {
+ for (counter = 0; counter < nr_counters; counter++)
+ mmap_read(&mmap_array[i][counter]);
+ }
+
+ if (hits == samples)
+ ret = poll(event_array, nr_poll, 100);
+ }
+
+ /*
+ * Approximate RIP event size: 24 bytes.
+ */
+ fprintf(stderr,
+ "[ perf record: Captured and wrote %.3f MB %s (~%lld samples) ]\n",
+ (double)bytes_written / 1024.0 / 1024.0,
+ output_name,
+ bytes_written / 24);
+
+ return 0;
+}
+
+static const char * const record_usage[] = {
+ "perf record [<options>] [<command>]",
+ "perf record [<options>] -- <command> [<options>]",
+ NULL
+};
+
+static const struct option options[] = {
+ OPT_CALLBACK('e', "event", NULL, "event",
+ "event selector. use 'perf list' to list available events",
+ parse_events),
+ OPT_INTEGER('p', "pid", &target_pid,
+ "record events on existing pid"),
+ OPT_INTEGER('r', "realtime", &realtime_prio,
+ "collect data with this RT SCHED_FIFO priority"),
+ OPT_BOOLEAN('a', "all-cpus", &system_wide,
+ "system-wide collection from all CPUs"),
+ OPT_BOOLEAN('A', "append", &append_file,
+ "append to the output file to do incremental profiling"),
+ OPT_BOOLEAN('f', "force", &force,
+ "overwrite existing data file"),
+ OPT_LONG('c', "count", &default_interval,
+ "event period to sample"),
+ OPT_STRING('o', "output", &output_name, "file",
+ "output file name"),
+ OPT_BOOLEAN('i', "inherit", &inherit,
+ "child tasks inherit counters"),
+ OPT_INTEGER('F', "freq", &freq,
+ "profile at this frequency"),
+ OPT_INTEGER('m', "mmap-pages", &mmap_pages,
+ "number of mmap data pages"),
+ OPT_END()
+};
+
+int cmd_record(int argc, const char **argv, const char *prefix)
+{
+ int counter;
+
+ argc = parse_options(argc, argv, options, record_usage, 0);
+ if (!argc && target_pid == -1 && !system_wide)
+ usage_with_options(record_usage, options);
+
+ if (!nr_counters)
+ nr_counters = 1;
+
+ for (counter = 0; counter < nr_counters; counter++) {
+ if (attrs[counter].sample_period)
+ continue;
+
+ attrs[counter].sample_period = default_interval;
+ }
+
+ return __cmd_record(argc, argv);
+}
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