src/util/u_thread.h

   1 /**************************************************************************
   2  *
   3  * Copyright 1999-2006 Brian Paul
   4  * Copyright 2008 VMware, Inc.
   5  * All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  **************************************************************************/
  26
  27 #ifndef U_THREAD_H_
  28 #define U_THREAD_H_
  29
  30 #include <stdint.h>
  31 #include <stdbool.h>
  32
  33 #include "c11/threads.h"
  34 #include "detect_os.h"
  35
  36 #ifdef HAVE_PTHREAD
  37 #include <signal.h>
  38 #ifdef PTHREAD_SETAFFINITY_IN_NP_HEADER
  39 #include <pthread_np.h>
  40 #endif
  41 #endif
  42
  43 #ifdef __FreeBSD__
  44 #define cpu_set_t cpuset_t
  45 #endif
  46
  47 static inline thrd_t u_thread_create(int (*routine)(void *), void *param)
  48 {
  49    thrd_t thread;
  50 #ifdef HAVE_PTHREAD
  51    sigset_t saved_set, new_set;
  52    int ret;
  53
  54    sigfillset(&new_set);
  55    sigdelset(&new_set, SIGSYS);
  56    pthread_sigmask(SIG_BLOCK, &new_set, &saved_set);
  57    ret = thrd_create( &thread, routine, param );
  58    pthread_sigmask(SIG_SETMASK, &saved_set, NULL);
  59 #else
  60    int ret;
  61    ret = thrd_create( &thread, routine, param );
  62 #endif
  63    if (ret)
  64       return 0;
  65
  66    return thread;
  67 }
  68
  69 static inline void u_thread_setname( const char *name )
  70 {
  71 #if defined(HAVE_PTHREAD)
  72 #if DETECT_OS_LINUX || DETECT_OS_CYGWIN
  73    pthread_setname_np(pthread_self(), name);
  74 #elif DETECT_OS_FREEBSD || DETECT_OS_OPENBSD
  75    pthread_set_name_np(pthread_self(), name);
  76 #elif DETECT_OS_NETBSD
  77    pthread_setname_np(pthread_self(), "%s", (void *)name);
  78 #elif DETECT_OS_APPLE
  79    pthread_setname_np(name);
  80 #else
  81 #error Not sure how to call pthread_setname_np
  82 #endif
  83 #endif
  84    (void)name;
  85 }
  86
  87 /**
  88  * An AMD Zen CPU consists of multiple modules where each module has its own L3
  89  * cache. Inter-thread communication such as locks and atomics between modules
  90  * is very expensive. It's desirable to pin a group of closely cooperating
  91  * threads to one group of cores sharing L3.
  92  *
  93  * \param thread        thread
  94  * \param L3_index      index of the L3 cache
  95  * \param cores_per_L3  number of CPU cores shared by one L3
  96  */
  97 static inline void
  98 util_pin_thread_to_L3(thrd_t thread, unsigned L3_index, unsigned cores_per_L3)
  99 {
 100 #if defined(HAVE_PTHREAD_SETAFFINITY)
 101    cpu_set_t cpuset;
 102
 103    CPU_ZERO(&cpuset);
 104    for (unsigned i = 0; i < cores_per_L3; i++)
 105       CPU_SET(L3_index * cores_per_L3 + i, &cpuset);
 106    pthread_setaffinity_np(thread, sizeof(cpuset), &cpuset);
 107 #endif
 108 }
 109
 110 /**
 111  * Return the index of L3 that the thread is pinned to. If the thread is
 112  * pinned to multiple L3 caches, return -1.
 113  *
 114  * \param thread        thread
 115  * \param cores_per_L3  number of CPU cores shared by one L3
 116  */
 117 static inline int
 118 util_get_L3_for_pinned_thread(thrd_t thread, unsigned cores_per_L3)
 119 {
 120 #if defined(HAVE_PTHREAD_SETAFFINITY)
 121    cpu_set_t cpuset;
 122
 123    if (pthread_getaffinity_np(thread, sizeof(cpuset), &cpuset) == 0) {
 124       int L3_index = -1;
 125
 126       for (unsigned i = 0; i < CPU_SETSIZE; i++) {
 127          if (CPU_ISSET(i, &cpuset)) {
 128             int x = i / cores_per_L3;
 129
 130             if (L3_index != x) {
 131                if (L3_index == -1)
 132                   L3_index = x;
 133                else
 134                   return -1; /* multiple L3s are set */
 135             }
 136          }
 137       }
 138       return L3_index;
 139    }
 140 #endif
 141    return -1;
 142 }
 143
 144 /*
 145  * Thread statistics.
 146  */
 147
 148 /* Return the time of a thread's CPU time clock. */
 149 static inline int64_t
 150 u_thread_get_time_nano(thrd_t thread)
 151 {
 152 #if defined(__linux__) && defined(HAVE_PTHREAD)
 153    struct timespec ts;
 154    clockid_t cid;
 155
 156    pthread_getcpuclockid(thread, &cid);
 157    clock_gettime(cid, &ts);
 158    return (int64_t)ts.tv_sec * 1000000000 + ts.tv_nsec;
 159 #else
 160    return 0;
 161 #endif
 162 }
 163
 164 static inline bool u_thread_is_self(thrd_t thread)
 165 {
 166 #if defined(HAVE_PTHREAD)
 167    return pthread_equal(pthread_self(), thread);
 168 #endif
 169    return false;
 170 }
 171
 172 /*
 173  * util_barrier
 174  */
 175
 176 #if defined(HAVE_PTHREAD) && !defined(__APPLE__)
 177
 178 typedef pthread_barrier_t util_barrier;
 179
 180 static inline void util_barrier_init(util_barrier *barrier, unsigned count)
 181 {
 182    pthread_barrier_init(barrier, NULL, count);
 183 }
 184
 185 static inline void util_barrier_destroy(util_barrier *barrier)
 186 {
 187    pthread_barrier_destroy(barrier);
 188 }
 189
 190 static inline void util_barrier_wait(util_barrier *barrier)
 191 {
 192    pthread_barrier_wait(barrier);
 193 }
 194
 195
 196 #else /* If the OS doesn't have its own, implement barriers using a mutex and a condvar */
 197
 198 typedef struct {
 199    unsigned count;
 200    unsigned waiters;
 201    uint64_t sequence;
 202    mtx_t mutex;
 203    cnd_t condvar;
 204 } util_barrier;
 205
 206 static inline void util_barrier_init(util_barrier *barrier, unsigned count)
 207 {
 208    barrier->count = count;
 209    barrier->waiters = 0;
 210    barrier->sequence = 0;
 211    (void) mtx_init(&barrier->mutex, mtx_plain);
 212    cnd_init(&barrier->condvar);
 213 }
 214
 215 static inline void util_barrier_destroy(util_barrier *barrier)
 216 {
 217    assert(barrier->waiters == 0);
 218    mtx_destroy(&barrier->mutex);
 219    cnd_destroy(&barrier->condvar);
 220 }
 221
 222 static inline void util_barrier_wait(util_barrier *barrier)
 223 {
 224    mtx_lock(&barrier->mutex);
 225
 226    assert(barrier->waiters < barrier->count);
 227    barrier->waiters++;
 228
 229    if (barrier->waiters < barrier->count) {
 230       uint64_t sequence = barrier->sequence;
 231
 232       do {
 233          cnd_wait(&barrier->condvar, &barrier->mutex);
 234       } while (sequence == barrier->sequence);
 235    } else {
 236       barrier->waiters = 0;
 237       barrier->sequence++;
 238       cnd_broadcast(&barrier->condvar);
 239    }
 240
 241    mtx_unlock(&barrier->mutex);
 242 }
 243
 244 #endif
 245
 246 #endif /* U_THREAD_H_ */