libpfms.c

Go to the documentation of this file.

#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <pthread.h>
#include <semaphore.h>
#include <inttypes.h>
#include <syscall.h>
#include <errno.h>
#include <stdarg.h>
 
#include <perfmon/perfmon.h>
 
#include "libpfms.h"
 
//#define dprint(format, arg...) fprintf(stderr, "%s.%d: " format , __FUNCTION__ , __LINE__, ## arg)
#define dprint(format, arg...)
 
typedef enum {  CMD_NONE,
        CMD_CTX,
        CMD_LOAD,
        CMD_UNLOAD,
        CMD_WPMCS,
        CMD_WPMDS,
        CMD_RPMDS,
        CMD_STOP,
        CMD_START,
        CMD_CLOSE
} pfms_cmd_t;
 
typedef struct _barrier {
    pthread_mutex_t mutex;
    pthread_cond_t  cond;
    uint32_t    counter;
    uint32_t    max;
    uint64_t    generation; /* avoid race condition on wake-up */
} barrier_t;
 
typedef struct {
    uint32_t    cpu;
    uint32_t    fd;
    void        *smpl_vaddr;
    size_t      smpl_buf_size;
} pfms_cpu_t;
 
typedef struct _pfms_thread {
    uint32_t    cpu;
    pfms_cmd_t  cmd;
    void        *data;
    uint32_t    ndata;
    sem_t       cmd_sem;
    int     ret;
    pthread_t   tid;
    barrier_t   *barrier; 
} pfms_thread_t;
 
typedef struct  {
    barrier_t   barrier;
    uint32_t    ncpus;
} pfms_session_t;
 
static uint32_t ncpus;
static pfms_thread_t    *tds;
static pthread_mutex_t  tds_lock = PTHREAD_MUTEX_INITIALIZER;
 
static int
barrier_init(barrier_t *b, uint32_t count)
{
    int r;
 
    r = pthread_mutex_init(&b->mutex, NULL);
    if (r == -1) return -1;
 
    r = pthread_cond_init(&b->cond, NULL);
    if (r == -1) return -1;
 
    b->max = b->counter = count;
    b->generation = 0;
 
    return 0;
}
 
static void
cleanup_barrier(void *arg)
{
    barrier_t *b = (barrier_t *)arg;
    int r;
    r = pthread_mutex_unlock(&b->mutex);
    dprint("free barrier mutex r=%d\n", r);
    (void) r;
}
 
static int
barrier_wait(barrier_t *b)
{
    uint64_t generation;
    int oldstate;
 
    pthread_cleanup_push(cleanup_barrier, b);
 
    pthread_mutex_lock(&b->mutex);
 
    pthread_testcancel();
 
    if (--b->counter == 0) {
 
        /* reset barrier */
        b->counter = b->max;
        /*
         * bump generation number, this avoids thread getting stuck in the
         * wake up loop below in case a thread just out of the barrier goes
         * back in right away before all the thread from the previous "round"
         * have "escaped".
         */
        b->generation++;
 
        pthread_cond_broadcast(&b->cond);
    } else {
 
        generation = b->generation;
 
        pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &oldstate);
 
        while (b->counter != b->max && generation == b->generation) {
            pthread_cond_wait(&b->cond, &b->mutex);
        }
 
        pthread_setcancelstate(oldstate, NULL);
    }
    pthread_mutex_unlock(&b->mutex);
 
    pthread_cleanup_pop(0);
 
    return 0;
}
 
/*
 * placeholder for pthread_setaffinity_np(). This stuff is ugly
 * and I could not figure out a way to get it compiled while also preserving
 * the pthread_*cancel(). There are issues with LinuxThreads and NPTL. I
 * decided to quit on this and implement my own affinity call until this 
 * settles.
 */
static int
pin_cpu(uint32_t cpu)
{
    uint64_t *mask;
    size_t size;
    pid_t pid;
    int ret;
 
    pid = syscall(__NR_gettid);
 
    size = ncpus * sizeof(uint64_t);
 
    mask = calloc(1, size);
    if (mask == NULL) {
        dprint("CPU%u: cannot allocate bitvector\n", cpu);
        return -1;
    }
    mask[cpu>>6] = 1ULL << (cpu & 63);
 
    ret = syscall(__NR_sched_setaffinity, pid, size, mask);
 
    free(mask);
 
    return ret;
}
 
static void
pfms_thread_mainloop(void *arg)
{
    long k = (long )arg;
    uint32_t mycpu = (uint32_t)k;
    pfarg_ctx_t myctx, *ctx;
    pfarg_load_t load_args;
    int fd = -1;
    pfms_thread_t *td;
    sem_t *cmd_sem;
    int ret = 0;
 
    memset(&load_args, 0, sizeof(load_args));
    load_args.load_pid = mycpu;
    td = tds+mycpu;
 
    ret = pin_cpu(mycpu);
    dprint("CPU%u wthread created and pinned ret=%d\n", mycpu, ret);
 
    cmd_sem = &tds[mycpu].cmd_sem;
 
    for(;;) {
        dprint("CPU%u waiting for cmd\n", mycpu);
 
        sem_wait(cmd_sem);
 
        switch(td->cmd) {
            case CMD_NONE:
                ret = 0;
                break;
 
            case CMD_CTX:
 
                /*
                 * copy context to get private fd
                 */
                ctx = td->data;
                myctx = *ctx;
 
                fd = pfm_create_context(&myctx, NULL, NULL, 0);
                ret = fd < 0 ? -1 : 0;
                dprint("CPU%u CMD_CTX ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
 
            case CMD_LOAD:
                ret = pfm_load_context(fd, &load_args);
                dprint("CPU%u CMD_LOAD ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_UNLOAD:
                ret = pfm_unload_context(fd);
                dprint("CPU%u CMD_UNLOAD ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_START:
                ret = pfm_start(fd, NULL);
                dprint("CPU%u CMD_START ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_STOP:
                ret = pfm_stop(fd);
                dprint("CPU%u CMD_STOP ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_WPMCS:
                ret = pfm_write_pmcs(fd,(pfarg_pmc_t *)td->data, td->ndata);
                dprint("CPU%u CMD_WPMCS ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_WPMDS:
                ret = pfm_write_pmds(fd,(pfarg_pmd_t *)td->data, td->ndata);
                dprint("CPU%u CMD_WPMDS ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_RPMDS:
                ret = pfm_read_pmds(fd,(pfarg_pmd_t *)td->data, td->ndata);
                dprint("CPU%u CMD_RPMDS ret=%d errno=%d fd=%d\n", mycpu, ret, errno, fd);
                break;
            case CMD_CLOSE:
                dprint("CPU%u CMD_CLOSE fd=%d\n", mycpu, fd);
                ret = close(fd);
                fd = -1;
                break;
            default:
                break;
        }
        td->ret = ret;
 
        dprint("CPU%u td->ret=%d\n", mycpu, ret);
 
        barrier_wait(td->barrier);
    }
}
 
static int
create_one_wthread(int cpu)
{
    int ret;
 
    sem_init(&tds[cpu].cmd_sem, 0, 0);
 
    ret = pthread_create(&tds[cpu].tid, 
                 NULL, 
                 (void *(*)(void *))pfms_thread_mainloop,
                 (void *)(long)cpu);
    return ret;
}
 
/*
 * must be called with tds_lock held
 */
static int
create_wthreads(uint64_t *cpu_list, uint32_t n)
{
    uint64_t v;
    uint32_t i,k, cpu;
    int ret = 0;
 
    for(k=0, cpu = 0; k < n; k++, cpu+= 64) {
        v = cpu_list[k];
        for(i=0; v && i < 63; i++, v>>=1, cpu++) {
            if ((v & 0x1) && tds[cpu].tid == 0) {
                ret = create_one_wthread(cpu);
                if (ret) break;
            }
        }
    }
 
    if (ret)
        dprint("cannot create wthread on CPU%u\n", cpu);
 
    return ret;
}
 
int
pfms_initialize(void)
{
    printf("cpu_t=%zu thread=%zu session_t=%zu\n",
        sizeof(pfms_cpu_t),
        sizeof(pfms_thread_t),
        sizeof(pfms_session_t));
 
    ncpus = (uint32_t)sysconf(_SC_NPROCESSORS_ONLN);
    if (ncpus == -1) {
        dprint("cannot retrieve number of online processors\n");
        return -1;
    }
 
    dprint("configured for %u CPUs\n", ncpus);
 
    /*
     * XXX: assuming CPU are contiguously indexed
     */
    tds = calloc(ncpus, sizeof(*tds));
    if (tds == NULL) {
        dprint("cannot allocate thread descriptors\n");
        return -1;
    }
    return 0;
}
 
int
pfms_create(uint64_t *cpu_list, size_t n, pfarg_ctx_t *ctx, pfms_ovfl_t *ovfl, void **desc)
{
    uint64_t v;
    size_t k, i;
    uint32_t num, cpu;
    pfms_session_t *s;
    int ret;
 
    if (cpu_list == NULL || n == 0 || ctx == NULL || desc == NULL) {
        dprint("invalid parameters\n");
        return -1;
    }
 
    if ((ctx->ctx_flags & PFM_FL_SYSTEM_WIDE) == 0) {
        dprint("only works for system wide\n");
        return -1;
    }
 
    *desc = NULL;
 
    /*
     * XXX: assuming CPU are contiguously indexed
     */
    num = 0;
    for(k=0, cpu = 0; k < n; k++, cpu+=64) {
        v = cpu_list[k];
        for(i=0; v && i < 63; i++, v>>=1, cpu++) {
            if (v & 0x1) {
                if (cpu >= ncpus) {
                    dprint("unavailable CPU%u\n", cpu);
                    return -1;
                }
                num++;
            }
        }
    }
 
    if (num == 0)
        return 0;
 
    s = calloc(1, sizeof(*s));
    if (s == NULL) {
        dprint("cannot allocate %u contexts\n", num);
        return -1;
    }
    s->ncpus = num;
 
    printf("%u-way  session\n", num);
 
    /*
     * +1 to account for main thread waiting
     */
    ret = barrier_init(&s->barrier, num + 1);
    if (ret) {
        dprint("cannot init barrier\n");
        goto error_free;
    }
 
    /*
     * lock thread descriptor table, no other create_session, close_session
     * can occur
     */
    pthread_mutex_lock(&tds_lock);
 
    if (create_wthreads(cpu_list, n))
        goto error_free_unlock;
 
    /*
     * check all needed threads are available
     */
    for(k=0, cpu = 0; k < n; k++, cpu += 64) {
        v = cpu_list[k];
        for(i=0; v && i < 63; i++, v>>=1, cpu++) {
            if (v & 0x1) {
                if (tds[cpu].barrier) {
                    dprint("CPU%u already managing a session\n", cpu);
                    goto error_free_unlock;
                }
 
            }
        }
    }
 
    /*
     * send create context order
     */
    for(k=0, cpu = 0; k < n; k++, cpu += 64) {
        v = cpu_list[k];
        for(i=0; v && i < 63; i++, v>>=1, cpu++) {
            if (v & 0x1) {
                tds[cpu].cmd  = CMD_CTX;
                tds[cpu].data = ctx;
                tds[cpu].barrier = &s->barrier;
                sem_post(&tds[cpu].cmd_sem);
            }
        }
    }
    barrier_wait(&s->barrier);
 
    ret = 0;
 
    /*
     * check for errors
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            ret = tds[k].ret;
            if (ret)
                break;
        }
    }
    /*
     * undo if error found
     */
    if (k < ncpus) {
        for(k=0; k < ncpus; k++) {
            if (tds[k].barrier == &s->barrier) {
                if (tds[k].ret == 0) {
                    tds[k].cmd = CMD_CLOSE;
                    sem_post(&tds[k].cmd_sem);
                }
                /* mark as free */
                tds[k].barrier = NULL;
            }
        }
    }
    pthread_mutex_unlock(&tds_lock);
 
    if (ret == 0) *desc = s;
 
    return ret ? -1 : 0;
 
error_free_unlock:
    pthread_mutex_unlock(&tds_lock);
 
error_free:
    free(s);
    return -1;
}
 
int
pfms_load(void *desc)
{
    uint32_t k;
    pfms_session_t *s;
    int ret;
 
    if (desc == NULL) {
        dprint("invalid parameters\n");
        return -1;
    }
    s = (pfms_session_t *)desc;
 
    if (s->ncpus == 0) {
        dprint("invalid session content 0 CPUS\n");
        return -1;
    }
    /*
     * send create context order
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            tds[k].cmd  = CMD_LOAD;
            sem_post(&tds[k].cmd_sem);
        }
    }
 
    barrier_wait(&s->barrier);
 
    ret = 0;
 
    /*
     * check for errors
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            ret = tds[k].ret;
            if (ret) {
                dprint("failure on CPU%u\n", k);
                break;
            }
        }
    }
 
    /*
     * if error, unload all others
     */
    if (k < ncpus) {
        for(k=0; k < ncpus; k++) {
            if (tds[k].barrier == &s->barrier) {
                if (tds[k].ret == 0) {
                    tds[k].cmd = CMD_UNLOAD;
                    sem_post(&tds[k].cmd_sem);
                }
            }
        }
    }
    return ret ? -1 : 0;
}
 
static int
__pfms_do_simple_cmd(pfms_cmd_t cmd, void *desc, void *data, uint32_t n)
{
    size_t k;
    pfms_session_t *s;
    int ret;
 
    if (desc == NULL) {
        dprint("invalid parameters\n");
        return -1;
    }
    s = (pfms_session_t *)desc;
 
    if (s->ncpus == 0) {
        dprint("invalid session content 0 CPUS\n");
        return -1;
    }
    /*
     * send create context order
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            tds[k].cmd  = cmd;
            tds[k].data = data;
            tds[k].ndata = n;
            sem_post(&tds[k].cmd_sem);
        }
    }
    barrier_wait(&s->barrier);
 
    ret = 0;
 
    /*
     * check for errors
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            ret = tds[k].ret;
            if (ret) {
                dprint("failure on CPU%zu\n", k);
                break;
            }
        }
    }
    /*
     * simple commands cannot be undone
     */
    return ret ? -1 : 0;
}
 
int
pfms_unload(void *desc)
{
    return __pfms_do_simple_cmd(CMD_UNLOAD, desc, NULL, 0);
}
 
int
pfms_start(void *desc)
{
    return __pfms_do_simple_cmd(CMD_START, desc, NULL, 0);
}
 
int
pfms_stop(void *desc)
{
    return __pfms_do_simple_cmd(CMD_STOP, desc, NULL, 0);
}
 
int
pfms_write_pmcs(void *desc, pfarg_pmc_t *pmcs, uint32_t n)
{
    return __pfms_do_simple_cmd(CMD_WPMCS, desc, pmcs, n);
}
 
int
pfms_write_pmds(void *desc, pfarg_pmd_t *pmds, uint32_t n)
{
    return __pfms_do_simple_cmd(CMD_WPMDS, desc, pmds, n);
}
 
int
pfms_close(void *desc)
{
    size_t k;
    pfms_session_t *s;
    int ret;
 
    if (desc == NULL) {
        dprint("invalid parameters\n");
        return -1;
    }
    s = (pfms_session_t *)desc;
 
    if (s->ncpus == 0) {
        dprint("invalid session content 0 CPUS\n");
        return -1;
    }
 
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            tds[k].cmd  = CMD_CLOSE;
            sem_post(&tds[k].cmd_sem);
        }
    }
    barrier_wait(&s->barrier);
 
    ret = 0;
 
    pthread_mutex_lock(&tds_lock);
    /*
     * check for errors
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            if (tds[k].ret) {
                dprint("failure on CPU%zu\n", k);
            }
            ret |= tds[k].ret;
            tds[k].barrier = NULL;
        }
    }
 
    pthread_mutex_unlock(&tds_lock);
 
    free(s);
 
    /*
     * XXX: we cannot undo close
     */
    return ret ? -1 : 0;
}
 
int
pfms_read_pmds(void *desc, pfarg_pmd_t *pmds, uint32_t n)
{
    pfms_session_t *s;
    uint32_t k, pmds_per_cpu;
    int ret;
 
    if (desc == NULL) {
        dprint("invalid parameters\n");
        return -1;
    }
    s = (pfms_session_t *)desc;
 
    if (s->ncpus == 0) {
        dprint("invalid session content 0 CPUS\n");
        return -1;
    }
    if (n % s->ncpus) {
        dprint("invalid number of pfarg_pmd_t provided, must be multiple of %u\n", s->ncpus);
        return -1;
    }
    pmds_per_cpu = n / s->ncpus;
 
    dprint("n=%u ncpus=%u per_cpu=%u\n", n, s->ncpus, pmds_per_cpu);
 
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            tds[k].cmd  = CMD_RPMDS;
            tds[k].data = pmds;
            tds[k].ndata= pmds_per_cpu;
            sem_post(&tds[k].cmd_sem);
            pmds += pmds_per_cpu;
        }
    }
    barrier_wait(&s->barrier);
 
    ret = 0;
 
    /*
     * check for errors
     */
    for(k=0; k < ncpus; k++) {
        if (tds[k].barrier == &s->barrier) {
            ret = tds[k].ret;
            if (ret) {
                dprint("failure on CPU%u\n", k);
                break;
            }
        }
    }
    /*
     * cannot undo pfm_read_pmds
     */
    return ret ? -1 : 0;
}
#if 0
 
/*
 * beginning of test program
 */
#include <perfmon/pfmlib.h>
 
#define NUM_PMCS PFMLIB_MAX_PMCS
#define NUM_PMDS PFMLIB_MAX_PMDS
 
static void fatal_error(char *fmt,...) __attribute__((noreturn));
 
static void
fatal_error(char *fmt, ...)
{
    va_list ap;
 
    va_start(ap, fmt);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
 
    exit(1);
}
 
static uint32_t
popcount(uint64_t c)
{
    uint32_t count = 0;
 
    for(; c; c>>=1) {
        if (c & 0x1)
            count++;
    }
    return count;
}
 
int
main(int argc, char **argv)
{
    pfarg_ctx_t ctx;
    pfarg_pmc_t pc[NUM_PMCS];
    pfarg_pmd_t *pd;
    pfmlib_input_param_t inp;
    pfmlib_output_param_t outp;
    uint64_t cpu_list;
    void *desc;
    unsigned int num_counters;
    uint32_t i, j, k, l, ncpus, npmds;
    size_t len;
    int ret;
    char *name;
 
    if (pfm_initialize() != PFMLIB_SUCCESS)
        fatal_error("cannot initialize libpfm\n");
 
    if (pfms_initialize())
        fatal_error("cannot initialize libpfms\n");
 
    pfm_get_num_counters(&num_counters);
    pfm_get_max_event_name_len(&len);
 
    name = malloc(len+1);
    if (name == NULL)
        fatal_error("cannot allocate memory for event name\n");
 
    memset(&ctx, 0, sizeof(ctx));
    memset(pc, 0, sizeof(pc));
    memset(&inp,0, sizeof(inp));
    memset(&outp,0, sizeof(outp));
 
    cpu_list = argc > 1 ? strtoul(argv[1], NULL, 0) : 0x3;
 
    ncpus = popcount(cpu_list);
 
        if (pfm_get_cycle_event(&inp.pfp_events[0].event) != PFMLIB_SUCCESS)
        fatal_error("cannot find cycle event\n");
 
    if (pfm_get_inst_retired_event(&inp.pfp_events[1].event) != PFMLIB_SUCCESS)
        fatal_error("cannot find inst retired event\n");
 
    i = 2;
 
    inp.pfp_dfl_plm = PFM_PLM3|PFM_PLM0;
 
    if (i > num_counters) {
        i = num_counters;
        printf("too many events provided (max=%d events), using first %d event(s)\n", num_counters, i);
    }
    /*
     * how many counters we use
     */
    inp.pfp_event_count = i;
 
    /*
     * indicate we are using the monitors for a system-wide session.
     * This may impact the way the library sets up the PMC values.
     */
    inp.pfp_flags = PFMLIB_PFP_SYSTEMWIDE;
 
    /*
     * let the library figure out the values for the PMCS
     */
    if ((ret=pfm_dispatch_events(&inp, NULL, &outp, NULL)) != PFMLIB_SUCCESS)
        fatal_error("cannot configure events: %s\n", pfm_strerror(ret));
 
    npmds = ncpus * inp.pfp_event_count;
    dprint("ncpus=%u npmds=%u\n", ncpus, npmds);
 
    pd = calloc(npmds, sizeof(pfarg_pmd_t));
    if (pd == NULL)
        fatal_error("cannot allocate pd array\n");
 
    for (i=0; i < outp.pfp_pmc_count; i++) {
        pc[i].reg_num   = outp.pfp_pmcs[i].reg_num;
        pc[i].reg_value = outp.pfp_pmcs[i].reg_value;
    }
 
    for(l=0, k = 0; l < ncpus; l++) {
        for (i=0, j=0; i < inp.pfp_event_count; i++, k++) {
            pd[k].reg_num   = outp.pfp_pmcs[j].reg_pmd_num;
            for(; j < outp.pfp_pmc_count; j++)  if (outp.pfp_pmcs[j].reg_evt_idx != i) break;
        }
    }
 
    /*
     * create a context on all CPUs we asked for
     *
     * libpfms only works for system-wide, so we set the flag in
     * the master context. the context argument is not modified by
     * call.
     *
     * desc is an opaque descriptor used to identify session.
     */
    ctx.ctx_flags = PFM_FL_SYSTEM_WIDE;
 
    ret = pfms_create(&cpu_list, 1, &ctx, NULL, &desc);
    if (ret == -1)
        fatal_error("create error %d\n", ret);
 
    /*
     * program the PMC registers on all CPUs of interest
     */
    ret = pfms_write_pmcs(desc, pc, outp.pfp_pmc_count);
    if (ret == -1)
        fatal_error("write_pmcs error %d\n", ret);
 
    /*
     * program the PMD registers on all CPUs of interest
     */
    ret = pfms_write_pmds(desc, pd, inp.pfp_event_count);
    if (ret == -1)
        fatal_error("write_pmds error %d\n", ret);
 
    /*
     * load context on all CPUs of interest
     */
    ret = pfms_load(desc);
    if (ret == -1)
        fatal_error("load error %d\n", ret);
 
    /*
     * start monitoring on all CPUs of interest
     */
    ret = pfms_start(desc);
    if (ret == -1)
        fatal_error("start error %d\n", ret);
 
    /*
     * simulate some work
     */
    sleep(10);
 
    /*
     * stop monitoring on all CPUs of interest
     */
    ret = pfms_stop(desc);
    if (ret == -1)
        fatal_error("stop error %d\n", ret);
    
    /*
     * read the PMD registers on all CPUs of interest.
     * The pd[] array must be organized such that to
     * read 2 PMDs on each CPU you need:
     *  - 2 * number of CPUs of interest
     *  - the first 2 elements of pd[] read on 1st CPU
     *  - the next  2 elements of pd[] read on the 2nd CPU
     *  - and so on
     */
    ret = pfms_read_pmds(desc, pd, npmds);
    if (ret == -1)
        fatal_error("read_pmds error %d\n", ret);
 
    /*
     * pre per-CPU results
     */
    for(j=0, k= 0; j < ncpus; j++) {
        for (i=0; i < inp.pfp_event_count; i++, k++) {
            pfm_get_full_event_name(&inp.pfp_events[i], name, len);
            printf("CPU%-3d PMD%u %20"PRIu64" %s\n",
            j,
            pd[k].reg_num,
            pd[k].reg_value,
            name);
        }
    }
 
    /*
     * destroy context  on all CPUs of interest.
     * After this call desc is invalid
     */
    ret = pfms_close(desc);
    if (ret == -1)
        fatal_error("close error %d\n", ret);
 
    free(name);
 
    return 0;
}
#endif