-#else /* #ifdef DEBUG_FULL_MB */
-#ifdef HAS_INCOHERENT_CACHES
-static void force_mb_single_thread(struct reader_registry *index)
-{
- assert(registry);
- /*
- * pthread_kill has a smp_mb(). But beware, we assume it performs
- * a cache flush on architectures with non-coherent cache. Let's play
- * safe and don't assume anything : we use smp_mc() to make sure the
- * cache flush is enforced.
- */
- *index->need_mb = 1;
- smp_mc(); /* write ->need_mb before sending the signals */
- pthread_kill(index->tid, SIGURCU);
- smp_mb();
- /*
- * Wait for sighandler (and thus mb()) to execute on every thread.
- * BUSY-LOOP.
- */
- while (*index->need_mb) {
- poll(NULL, 0, 1);
- }
- smp_mb(); /* read ->need_mb before ending the barrier */
-}
-#endif /* #ifdef HAS_INCOHERENT_CACHES */
-
-static void force_mb_all_threads(void)
-{
- struct reader_registry *index;
- /*
- * Ask for each threads to execute a smp_mb() so we can consider the
- * compiler barriers around rcu read lock as real memory barriers.
- */
- if (!registry)
- return;
- /*
- * pthread_kill has a smp_mb(). But beware, we assume it performs
- * a cache flush on architectures with non-coherent cache. Let's play
- * safe and don't assume anything : we use smp_mc() to make sure the
- * cache flush is enforced.
- */
- for (index = registry; index < registry + num_readers; index++) {
- *index->need_mb = 1;
- smp_mc(); /* write need_mb before sending the signal */
- pthread_kill(index->tid, SIGURCU);
- }
- /*
- * Wait for sighandler (and thus mb()) to execute on every thread.
- *
- * Note that the pthread_kill() will never be executed on systems
- * that correctly deliver signals in a timely manner. However, it
- * is not uncommon for kernels to have bugs that can result in
- * lost or unduly delayed signals.
- *
- * If you are seeing the below pthread_kill() executing much at
- * all, we suggest testing the underlying kernel and filing the
- * relevant bug report. For Linux kernels, we recommend getting
- * the Linux Test Project (LTP).
- */
- for (index = registry; index < registry + num_readers; index++) {
- while (*index->need_mb) {
- pthread_kill(index->tid, SIGURCU);
- poll(NULL, 0, 1);
- }
- }
- smp_mb(); /* read ->need_mb before ending the barrier */
-}
-#endif /* #else #ifdef DEBUG_FULL_MB */