1 files changed, 628 insertions, 0 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
new file mode 100644
index 00000000000..d7ebbd75754
--- /dev/null
+++ b/tools/perf/builtin-record.c
@@ -0,0 +1,628 @@
+/*
+ * 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 int                      call_graph                      = 0;
+static int                      verbose                         = 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;
+
+static int                      file_new = 1;
+static struct perf_file_header  file_header;
+
+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 long mmap_read_head(struct mmap_data *md)
+{
+        struct perf_counter_mmap_page *pc = md->base;
+        long head;
+
+        head = pc->data_head;
+        rmb();
+
+        return head;
+}
+
+static void mmap_write_tail(struct mmap_data *md, unsigned long tail)
+{
+        struct perf_counter_mmap_page *pc = md->base;
+
+        /*
+         * ensure all reads are done before we write the tail out.
+         */
+        /* mb(); */
+        pc->data_tail = tail;
+}
+
+static void write_output(void *buf, size_t size)
+{
+        while (size) {
+                int ret = write(output, buf, size);
+
+                if (ret < 0)
+                        die("failed to write");
+
+                size -= ret;
+                buf += ret;
+
+                bytes_written += ret;
+        }
+}
+
+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 < 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;
+
+                write_output(buf, size);
+        }
+
+        buf = &data[old & md->mask];
+        size = head - old;
+        old += size;
+
+        write_output(buf, size);
+
+        md->prev = old;
+        mmap_write_tail(md, old);
+}
+
+static volatile int done = 0;
+static volatile int signr = -1;
+
+static void sig_handler(int sig)
+{
+        done = 1;
+        signr = sig;
+}
+
+static void sig_atexit(void)
+{
+        if (signr == -1)
+                return;
+
+        signal(signr, SIG_DFL);
+        kill(getpid(), signr);
+}
+
+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;
+        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) {
+                /*
+                 * We raced with a task exiting - just return:
+                 */
+                if (verbose)
+                        fprintf(stderr, "couldn't open %s\n", filename);
+                return;
+        }
+        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(u64));
+        comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);
+
+        if (!full) {
+                comm_ev.tid = pid;
+
+                write_output(&comm_ev, comm_ev.header.size);
+                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;
+
+                write_output(&comm_ev, comm_ev.header.size);
+        }
+        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) {
+                /*
+                 * We raced with a task exiting - just return:
+                 */
+                if (verbose)
+                        fprintf(stderr, "couldn't open %s\n", filename);
+                return;
+        }
+        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(u64));
+                        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;
+
+                        write_output(&mmap_ev, mmap_ev.header.size);
+                }
+        }
+
+        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;
+
+        if (freq) {
+                attr->sample_type       |= PERF_SAMPLE_PERIOD;
+                attr->freq              = 1;
+                attr->sample_freq       = freq;
+        }
+
+        if (call_graph)
+                attr->sample_type       |= PERF_SAMPLE_CALLCHAIN;
+
+        if (file_new) {
+                file_header.sample_type = attr->sample_type;
+        } else {
+                if (file_header.sample_type != attr->sample_type) {
+                        fprintf(stderr, "incompatible append\n");
+                        exit(-1);
+                }
+        }
+
+        attr->mmap              = track;
+        attr->comm              = track;
+        attr->inherit           = (cpu < 0) && inherit;
+        attr->disabled          = 1;
+
+        track = 0; /* only the first counter needs these */
+
+try_again:
+        fd[nr_cpu][counter] = sys_perf_counter_open(attr, pid, cpu, group_fd, 0);
+
+        if (fd[nr_cpu][counter] < 0) {
+                int err = errno;
+
+                if (err == EPERM)
+                        die("Permission error - are you root?\n");
+
+                /*
+                 * If it's cycles then fall back to hrtimer
+                 * based cpu-clock-tick sw counter, which
+                 * is always available even if no PMU support:
+                 */
+                if (attr->type == PERF_TYPE_HARDWARE
+                        && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
+
+                        if (verbose)
+                                warning(" ... trying to fall back to cpu-clock-ticks\n");
+                        attr->type = PERF_TYPE_SOFTWARE;
+                        attr->config = PERF_COUNT_SW_CPU_CLOCK;
+                        goto try_again;
+                }
+                printf("\n");
+                error("perfcounter syscall returned with %d (%s)\n",
+                        fd[nr_cpu][counter], strerror(err));
+                die("No CONFIG_PERF_COUNTERS=y kernel support configured?\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|PROT_WRITE, 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);
+        }
+
+        ioctl(fd[nr_cpu][counter], PERF_COUNTER_IOC_ENABLE);
+}
+
+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 void atexit_header(void)
+{
+        file_header.data_size += bytes_written;
+
+        if (pwrite(output, &file_header, sizeof(file_header), 0) == -1)
+                perror("failed to write on file headers");
+}
+
+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);
+
+        atexit(sig_atexit);
+        signal(SIGCHLD, sig_handler);
+        signal(SIGINT, sig_handler);
+
+        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)
+                file_new = 0;
+        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 (!file_new) {
+                if (read(output, &file_header, sizeof(file_header)) == -1) {
+                        perror("failed to read file headers");
+                        exit(-1);
+                }
+
+                lseek(output, file_header.data_size, SEEK_CUR);
+        }
+
+        atexit(atexit_header);
+
+        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);
+
+        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_BOOLEAN('g', "call-graph", &call_graph,
+                    "do call-graph (stack chain/backtrace) recording"),
+        OPT_BOOLEAN('v', "verbose", &verbose,
+                    "be more verbose (show counter open errors, etc)"),
+        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;
+                attrs[0].type   = PERF_TYPE_HARDWARE;
+                attrs[0].config = PERF_COUNT_HW_CPU_CYCLES;
+        }
+
+        for (counter = 0; counter < nr_counters; counter++) {
+                if (attrs[counter].sample_period)
+                        continue;
+
+                attrs[counter].sample_period = default_interval;
+        }
+
+        return __cmd_record(argc, argv);
+}