ofproto-dpif-rid: correct logic error in rid_pool_alloc_id()

[cascardo/ovs.git] / lib / ovs-thread.c

diff --git a/lib/ovs-thread.c b/lib/ovs-thread.c
index d835b39..529756f 100644 (file)
--- a/lib/ovs-thread.c
+++ b/lib/ovs-thread.c
@@ -24,6 +24,7 @@
 #include "hash.h"
 #include "ovs-rcu.h"
 #include "poll-loop.h"
+#include "seq.h"
 #include "socket-util.h"
 #include "util.h"
 
@@ -52,12 +53,20 @@ static bool multithreaded;
         OVS_NO_THREAD_SAFETY_ANALYSIS \
     { \
         struct ovs_##TYPE *l = CONST_CAST(struct ovs_##TYPE *, l_); \
-        int error = pthread_##TYPE##_##FUN(&l->lock); \
+        int error; \
+ \
+        /* Verify that 'l' was initialized. */ \
+        if (OVS_UNLIKELY(!l->where)) { \
+            ovs_abort(0, "%s: %s() passed uninitialized ovs_"#TYPE, \
+                      where, __func__); \
+        } \
+ \
+        error = pthread_##TYPE##_##FUN(&l->lock); \
         if (OVS_UNLIKELY(error)) { \
-            ovs_abort(error, "pthread_%s_%s failed", #TYPE, #FUN); \
+            ovs_abort(error, "%s: pthread_%s_%s failed", where, #TYPE, #FUN); \
         } \
         l->where = where; \
-    }
+ }
 LOCK_FUNCTION(mutex, lock);
 LOCK_FUNCTION(rwlock, rdlock);
 LOCK_FUNCTION(rwlock, wrlock);
@@ -69,9 +78,17 @@ LOCK_FUNCTION(rwlock, wrlock);
         OVS_NO_THREAD_SAFETY_ANALYSIS \
     { \
         struct ovs_##TYPE *l = CONST_CAST(struct ovs_##TYPE *, l_); \
-        int error = pthread_##TYPE##_##FUN(&l->lock); \
+        int error; \
+ \
+        /* Verify that 'l' was initialized. */ \
+        if (OVS_UNLIKELY(!l->where)) { \
+            ovs_abort(0, "%s: %s() passed uninitialized ovs_"#TYPE, \
+                      where, __func__); \
+        } \
+ \
+        error = pthread_##TYPE##_##FUN(&l->lock); \
         if (OVS_UNLIKELY(error) && error != EBUSY) { \
-            ovs_abort(error, "pthread_%s_%s failed", #TYPE, #FUN); \
+            ovs_abort(error, "%s: pthread_%s_%s failed", where, #TYPE, #FUN); \
         } \
         if (!error) { \
             l->where = where; \
@@ -82,23 +99,27 @@ TRY_LOCK_FUNCTION(mutex, trylock);
 TRY_LOCK_FUNCTION(rwlock, tryrdlock);
 TRY_LOCK_FUNCTION(rwlock, trywrlock);
 
-#define UNLOCK_FUNCTION(TYPE, FUN) \
+#define UNLOCK_FUNCTION(TYPE, FUN, WHERE) \
     void \
     ovs_##TYPE##_##FUN(const struct ovs_##TYPE *l_) \
         OVS_NO_THREAD_SAFETY_ANALYSIS \
     { \
         struct ovs_##TYPE *l = CONST_CAST(struct ovs_##TYPE *, l_); \
         int error; \
-        l->where = NULL; \
+ \
+        /* Verify that 'l' was initialized. */ \
+        ovs_assert(l->where); \
+ \
+        l->where = WHERE; \
         error = pthread_##TYPE##_##FUN(&l->lock); \
         if (OVS_UNLIKELY(error)) { \
             ovs_abort(error, "pthread_%s_%sfailed", #TYPE, #FUN); \
         } \
     }
-UNLOCK_FUNCTION(mutex, unlock);
-UNLOCK_FUNCTION(mutex, destroy);
-UNLOCK_FUNCTION(rwlock, unlock);
-UNLOCK_FUNCTION(rwlock, destroy);
+UNLOCK_FUNCTION(mutex, unlock, "<unlocked>");
+UNLOCK_FUNCTION(mutex, destroy, NULL);
+UNLOCK_FUNCTION(rwlock, unlock, "<unlocked>");
+UNLOCK_FUNCTION(rwlock, destroy, NULL);
 
 #define XPTHREAD_FUNC1(FUNCTION, PARAM1)                \
     void                                                \
@@ -146,10 +167,6 @@ XPTHREAD_FUNC1(pthread_cond_destroy, pthread_cond_t *);
 XPTHREAD_FUNC1(pthread_cond_signal, pthread_cond_t *);
 XPTHREAD_FUNC1(pthread_cond_broadcast, pthread_cond_t *);
 
-XPTHREAD_FUNC3(pthread_barrier_init, pthread_barrier_t *,
-               pthread_barrierattr_t *, unsigned int);
-XPTHREAD_FUNC1(pthread_barrier_destroy, pthread_barrier_t *);
-
 XPTHREAD_FUNC2(pthread_join, pthread_t, void **);
 
 typedef void destructor_func(void *);
@@ -164,7 +181,7 @@ ovs_mutex_init__(const struct ovs_mutex *l_, int type)
     pthread_mutexattr_t attr;
     int error;
 
-    l->where = NULL;
+    l->where = "<unlocked>";
     xpthread_mutexattr_init(&attr);
     xpthread_mutexattr_settype(&attr, type);
     error = pthread_mutex_init(&l->lock, &attr);
@@ -206,7 +223,7 @@ ovs_rwlock_init(const struct ovs_rwlock *l_)
     pthread_rwlockattr_t attr;
     int error;
 
-    l->where = NULL;
+    l->where = "<unlocked>";
 
     xpthread_rwlockattr_init(&attr);
 #ifdef PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP
@@ -235,20 +252,43 @@ ovs_mutex_cond_wait(pthread_cond_t *cond, const struct ovs_mutex *mutex_)
     }
 }
 
-int
-xpthread_barrier_wait(pthread_barrier_t *barrier)
+/* Initializes the 'barrier'.  'size' is the number of threads
+ * expected to hit the barrier. */
+void
+ovs_barrier_init(struct ovs_barrier *barrier, uint32_t size)
 {
-    int error;
+    barrier->size = size;
+    atomic_init(&barrier->count, 0);
+    barrier->seq = seq_create();
+}
 
-    ovsrcu_quiesce_start();
-    error = pthread_barrier_wait(barrier);
-    ovsrcu_quiesce_end();
+/* Destroys the 'barrier'. */
+void
+ovs_barrier_destroy(struct ovs_barrier *barrier)
+{
+    seq_destroy(barrier->seq);
+}
 
-    if (error && OVS_UNLIKELY(error != PTHREAD_BARRIER_SERIAL_THREAD)) {
-        ovs_abort(error, "pthread_barrier_wait failed");
+/* Makes the calling thread block on the 'barrier' until all
+ * 'barrier->size' threads hit the barrier. */
+void
+ovs_barrier_block(struct ovs_barrier *barrier)
+{
+    uint64_t seq = seq_read(barrier->seq);
+    uint32_t orig;
+
+    atomic_add(&barrier->count, 1, &orig);
+    if (orig + 1 == barrier->size) {
+        atomic_store(&barrier->count, 0);
+        seq_change(barrier->seq);
     }
 
-    return error;
+    /* To prevent thread from waking up by other event,
+     * keeps waiting for the change of 'barrier->seq'. */
+    while (seq == seq_read(barrier->seq)) {
+        seq_wait(barrier->seq, seq);
+        poll_block();
+    }
 }
 \f
 DEFINE_EXTERN_PER_THREAD_DATA(ovsthread_id, 0);
@@ -274,9 +314,11 @@ ovsthread_wrapper(void *aux_)
     aux = *auxp;
     free(auxp);
 
+    /* The order of the following calls is important, because
+     * ovsrcu_quiesce_end() saves a copy of the thread name. */
     set_subprogram_name("%s%u", aux.name, id);
-
     ovsrcu_quiesce_end();
+
     return aux.start(aux.arg);
 }
 
@@ -468,11 +510,11 @@ parse_cpuinfo(long int *n_cores)
                 break;
             }
 
-            if (cpu & (1 << id)) {
+            if (cpu & (1ULL << id)) {
                 /* We've already counted this package's cores. */
                 continue;
             }
-            cpu |= 1 << id;
+            cpu |= 1ULL << id;
 
             /* Find the number of cores for this package. */
             while (fgets(line, sizeof line, stream)) {