/*
- * Copyright (c) 2013 Nicira, Inc.
+ * Copyright (c) 2013, 2014, 2015 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include "ovs-thread.h"
#include <errno.h>
#include <poll.h>
+#ifndef _WIN32
+#include <signal.h>
+#endif
#include <stdlib.h>
#include <unistd.h>
#include "compiler.h"
+#include "fatal-signal.h"
+#include "hash.h"
+#include "list.h"
+#include "netdev-dpdk.h"
+#include "ovs-rcu.h"
#include "poll-loop.h"
+#include "seq.h"
#include "socket-util.h"
#include "util.h"
* cut-and-paste. Since "sparse" is just a checker, not a compiler, it
* doesn't matter that we don't define them. */
#else
-#include "vlog.h"
+#include "openvswitch/vlog.h"
VLOG_DEFINE_THIS_MODULE(ovs_thread);
void \
ovs_##TYPE##_##FUN##_at(const struct ovs_##TYPE *l_, \
const char *where) \
+ 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);
int \
ovs_##TYPE##_##FUN##_at(const struct ovs_##TYPE *l_, \
const char *where) \
+ 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; \
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); \
+ ovs_abort(error, "pthread_%s_%s failed", #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 \
ovs_abort(error, "%s failed", #FUNCTION); \
} \
}
+#define XPTHREAD_FUNC3(FUNCTION, PARAM1, PARAM2, PARAM3)\
+ void \
+ x##FUNCTION(PARAM1 arg1, PARAM2 arg2, PARAM3 arg3) \
+ { \
+ int error = FUNCTION(arg1, arg2, arg3); \
+ if (OVS_UNLIKELY(error)) { \
+ ovs_abort(error, "%s failed", #FUNCTION); \
+ } \
+ }
XPTHREAD_FUNC1(pthread_mutex_lock, pthread_mutex_t *);
XPTHREAD_FUNC1(pthread_mutex_unlock, pthread_mutex_t *);
XPTHREAD_FUNC2(pthread_mutexattr_settype, pthread_mutexattr_t *, int);
XPTHREAD_FUNC2(pthread_mutexattr_gettype, pthread_mutexattr_t *, int *);
+XPTHREAD_FUNC1(pthread_rwlockattr_init, pthread_rwlockattr_t *);
+XPTHREAD_FUNC1(pthread_rwlockattr_destroy, pthread_rwlockattr_t *);
+#ifdef PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP
+XPTHREAD_FUNC2(pthread_rwlockattr_setkind_np, pthread_rwlockattr_t *, int);
+#endif
+
XPTHREAD_FUNC2(pthread_cond_init, pthread_cond_t *, pthread_condattr_t *);
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_FUNC2(pthread_join, pthread_t, void **);
+
typedef void destructor_func(void *);
XPTHREAD_FUNC2(pthread_key_create, pthread_key_t *, destructor_func *);
+XPTHREAD_FUNC1(pthread_key_delete, pthread_key_t);
XPTHREAD_FUNC2(pthread_setspecific, pthread_key_t, const void *);
-void
-ovs_mutex_init(const struct ovs_mutex *l_, int type)
+#ifndef _WIN32
+XPTHREAD_FUNC3(pthread_sigmask, int, const sigset_t *, sigset_t *);
+#endif
+
+static void
+ovs_mutex_init__(const struct ovs_mutex *l_, int type)
{
struct ovs_mutex *l = CONST_CAST(struct ovs_mutex *, l_);
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);
xpthread_mutexattr_destroy(&attr);
}
+/* Initializes 'mutex' as a normal (non-recursive) mutex. */
+void
+ovs_mutex_init(const struct ovs_mutex *mutex)
+{
+ ovs_mutex_init__(mutex, PTHREAD_MUTEX_ERRORCHECK);
+}
+
+/* Initializes 'mutex' as a recursive mutex. */
+void
+ovs_mutex_init_recursive(const struct ovs_mutex *mutex)
+{
+ ovs_mutex_init__(mutex, PTHREAD_MUTEX_RECURSIVE);
+}
+
+/* Initializes 'mutex' as a recursive mutex. */
+void
+ovs_mutex_init_adaptive(const struct ovs_mutex *mutex)
+{
+#ifdef PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
+ ovs_mutex_init__(mutex, PTHREAD_MUTEX_ADAPTIVE_NP);
+#else
+ ovs_mutex_init(mutex);
+#endif
+}
+
void
ovs_rwlock_init(const struct ovs_rwlock *l_)
{
struct ovs_rwlock *l = CONST_CAST(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
+ xpthread_rwlockattr_setkind_np(
+ &attr, PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP);
+#endif
error = pthread_rwlock_init(&l->lock, NULL);
if (OVS_UNLIKELY(error)) {
ovs_abort(error, "pthread_rwlock_init failed");
}
+ xpthread_rwlockattr_destroy(&attr);
}
void
ovs_mutex_cond_wait(pthread_cond_t *cond, const struct ovs_mutex *mutex_)
{
struct ovs_mutex *mutex = CONST_CAST(struct ovs_mutex *, mutex_);
- int error = pthread_cond_wait(cond, &mutex->lock);
+ int error;
+
+ ovsrcu_quiesce_start();
+ error = pthread_cond_wait(cond, &mutex->lock);
+ ovsrcu_quiesce_end();
+
if (OVS_UNLIKELY(error)) {
ovs_abort(error, "pthread_cond_wait failed");
}
}
+/* 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)
+{
+ barrier->size = size;
+ atomic_count_init(&barrier->count, 0);
+ barrier->seq = seq_create();
+}
+
+/* Destroys the 'barrier'. */
void
-xpthread_create(pthread_t *threadp, pthread_attr_t *attr,
- void *(*start)(void *), void *arg)
+ovs_barrier_destroy(struct ovs_barrier *barrier)
{
+ seq_destroy(barrier->seq);
+}
+
+/* Makes the calling thread block on the 'barrier' until all
+ * 'barrier->size' threads hit the barrier.
+ * ovs_barrier provides the necessary acquire-release semantics to make
+ * the effects of prior memory accesses of all the participating threads
+ * visible on return and to prevent the following memory accesses to be
+ * reordered before the ovs_barrier_block(). */
+void
+ovs_barrier_block(struct ovs_barrier *barrier)
+{
+ uint64_t seq = seq_read(barrier->seq);
+ uint32_t orig;
+
+ orig = atomic_count_inc(&barrier->count);
+ if (orig + 1 == barrier->size) {
+ atomic_count_set(&barrier->count, 0);
+ /* seq_change() serves as a release barrier against the other threads,
+ * so the zeroed count is visible to them as they continue. */
+ seq_change(barrier->seq);
+ } else {
+ /* 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);
+
+struct ovsthread_aux {
+ void *(*start)(void *);
+ void *arg;
+ char name[16];
+};
+
+static void *
+ovsthread_wrapper(void *aux_)
+{
+ static atomic_count next_id = ATOMIC_COUNT_INIT(1);
+
+ struct ovsthread_aux *auxp = aux_;
+ struct ovsthread_aux aux;
+ unsigned int id;
+
+ id = atomic_count_inc(&next_id);
+ *ovsthread_id_get() = id;
+
+ aux = *auxp;
+ free(auxp);
+
+ /* The order of the following calls is important, because
+ * ovsrcu_quiesce_end() saves a copy of the thread name. */
+ char *subprogram_name = xasprintf("%s%u", aux.name, id);
+ set_subprogram_name(subprogram_name);
+ free(subprogram_name);
+ ovsrcu_quiesce_end();
+
+ return aux.start(aux.arg);
+}
+
+static void
+set_min_stack_size(pthread_attr_t *attr, size_t min_stacksize)
+{
+ size_t stacksize;
+ int error;
+
+ error = pthread_attr_getstacksize(attr, &stacksize);
+ if (error) {
+ ovs_abort(error, "pthread_attr_getstacksize failed");
+ }
+
+ if (stacksize < min_stacksize) {
+ error = pthread_attr_setstacksize(attr, min_stacksize);
+ if (error) {
+ ovs_abort(error, "pthread_attr_setstacksize failed");
+ }
+ }
+}
+
+/* Starts a thread that calls 'start(arg)'. Sets the thread's name to 'name'
+ * (suffixed by its ovsthread_id()). Returns the new thread's pthread_t. */
+pthread_t
+ovs_thread_create(const char *name, void *(*start)(void *), void *arg)
+{
+ struct ovsthread_aux *aux;
pthread_t thread;
int error;
forbid_forking("multiple threads exist");
multithreaded = true;
+ ovsrcu_quiesce_end();
+
+ aux = xmalloc(sizeof *aux);
+ aux->start = start;
+ aux->arg = arg;
+ ovs_strlcpy(aux->name, name, sizeof aux->name);
+
+ /* Some small systems use a default stack size as small as 80 kB, but OVS
+ * requires approximately 384 kB according to the following analysis:
+ * http://openvswitch.org/pipermail/dev/2016-January/065049.html
+ *
+ * We use 512 kB to give us some margin of error. */
+ pthread_attr_t attr;
+ pthread_attr_init(&attr);
+ set_min_stack_size(&attr, 512 * 1024);
- error = pthread_create(threadp ? threadp : &thread, attr, start, arg);
+ error = pthread_create(&thread, NULL, ovsthread_wrapper, aux);
if (error) {
ovs_abort(error, "pthread_create failed");
}
+ pthread_attr_destroy(&attr);
+ return thread;
}
\f
bool
ovsthread_once_start__(struct ovsthread_once *once)
{
ovs_mutex_lock(&once->mutex);
- if (!ovsthread_once_is_done__(once)) {
- return false;
+ /* Mutex synchronizes memory, so we get the current value of 'done'. */
+ if (!once->done) {
+ return true;
}
ovs_mutex_unlock(&once->mutex);
- return true;
+ return false;
}
void
ovsthread_once_done(struct ovsthread_once *once)
{
- atomic_store(&once->done, true);
+ /* We need release semantics here, so that the following store may not
+ * be moved ahead of any of the preceding initialization operations.
+ * A release atomic_thread_fence provides that prior memory accesses
+ * will not be reordered to take place after the following store. */
+ atomic_thread_fence(memory_order_release);
+ once->done = true;
ovs_mutex_unlock(&once->mutex);
}
\f
+bool
+single_threaded(void)
+{
+ return !multithreaded;
+}
+
/* Asserts that the process has not yet created any threads (beyond the initial
* thread).
*
}
}
+#ifndef _WIN32
/* Forks the current process (checking that this is allowed). Aborts with
* VLOG_FATAL if fork() returns an error, and otherwise returns the value
* returned by fork().
}
return pid;
}
+#endif
/* Notes that the process must not call fork() from now on, for the specified
* 'reason'. (The process may still fork() if it execs itself immediately
{
return !must_not_fork;
}
+\f
+/* ovsthread_stats. */
+
+void
+ovsthread_stats_init(struct ovsthread_stats *stats)
+{
+ int i;
+
+ ovs_mutex_init(&stats->mutex);
+ for (i = 0; i < ARRAY_SIZE(stats->buckets); i++) {
+ stats->buckets[i] = NULL;
+ }
+}
+
+void
+ovsthread_stats_destroy(struct ovsthread_stats *stats)
+{
+ ovs_mutex_destroy(&stats->mutex);
+}
+
+void *
+ovsthread_stats_bucket_get(struct ovsthread_stats *stats,
+ void *(*new_bucket)(void))
+{
+ unsigned int idx = ovsthread_id_self() & (ARRAY_SIZE(stats->buckets) - 1);
+ void *bucket = stats->buckets[idx];
+ if (!bucket) {
+ ovs_mutex_lock(&stats->mutex);
+ bucket = stats->buckets[idx];
+ if (!bucket) {
+ bucket = stats->buckets[idx] = new_bucket();
+ }
+ ovs_mutex_unlock(&stats->mutex);
+ }
+ return bucket;
+}
+
+size_t
+ovs_thread_stats_next_bucket(const struct ovsthread_stats *stats, size_t i)
+{
+ for (; i < ARRAY_SIZE(stats->buckets); i++) {
+ if (stats->buckets[i]) {
+ break;
+ }
+ }
+ return i;
+}
+
+\f
+/* Parses /proc/cpuinfo for the total number of physical cores on this system
+ * across all CPU packages, not counting hyper-threads.
+ *
+ * Sets *n_cores to the total number of cores on this system, or 0 if the
+ * number cannot be determined. */
+static void
+parse_cpuinfo(long int *n_cores)
+{
+ static const char file_name[] = "/proc/cpuinfo";
+ char line[128];
+ uint64_t cpu = 0; /* Support up to 64 CPU packages on a single system. */
+ long int cores = 0;
+ FILE *stream;
+
+ stream = fopen(file_name, "r");
+ if (!stream) {
+ VLOG_DBG("%s: open failed (%s)", file_name, ovs_strerror(errno));
+ return;
+ }
+
+ while (fgets(line, sizeof line, stream)) {
+ unsigned int id;
+
+ /* Find the next CPU package. */
+ if (ovs_scan(line, "physical id%*[^:]: %u", &id)) {
+ if (id > 63) {
+ VLOG_WARN("Counted over 64 CPU packages on this system. "
+ "Parsing %s for core count may be inaccurate.",
+ file_name);
+ cores = 0;
+ break;
+ }
+
+ if (cpu & (1ULL << id)) {
+ /* We've already counted this package's cores. */
+ continue;
+ }
+ cpu |= 1ULL << id;
+
+ /* Find the number of cores for this package. */
+ while (fgets(line, sizeof line, stream)) {
+ int count;
+
+ if (ovs_scan(line, "cpu cores%*[^:]: %u", &count)) {
+ cores += count;
+ break;
+ }
+ }
+ }
+ }
+ fclose(stream);
+
+ *n_cores = cores;
+}
+
+/* Returns the total number of cores on this system, or 0 if the number cannot
+ * be determined.
+ *
+ * Tries not to count hyper-threads, but may be inaccurate - particularly on
+ * platforms that do not provide /proc/cpuinfo, but also if /proc/cpuinfo is
+ * formatted different to the layout that parse_cpuinfo() expects. */
+int
+count_cpu_cores(void)
+{
+ static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
+ static long int n_cores;
+
+ if (ovsthread_once_start(&once)) {
+#ifndef _WIN32
+ parse_cpuinfo(&n_cores);
+ if (!n_cores) {
+ n_cores = sysconf(_SC_NPROCESSORS_ONLN);
+ }
+#else
+ SYSTEM_INFO sysinfo;
+ GetSystemInfo(&sysinfo);
+ n_cores = sysinfo.dwNumberOfProcessors;
+#endif
+ ovsthread_once_done(&once);
+ }
+
+ return n_cores > 0 ? n_cores : 0;
+}
+
+/* Returns 'true' if current thread is PMD thread. */
+bool
+thread_is_pmd(void)
+{
+ const char *name = get_subprogram_name();
+ return !strncmp(name, "pmd", 3);
+}
+
+\f
+/* ovsthread_key. */
+
+#define L1_SIZE 1024
+#define L2_SIZE 1024
+#define MAX_KEYS (L1_SIZE * L2_SIZE)
+
+/* A piece of thread-specific data. */
+struct ovsthread_key {
+ struct ovs_list list_node; /* In 'inuse_keys' or 'free_keys'. */
+ void (*destructor)(void *); /* Called at thread exit. */
+
+ /* Indexes into the per-thread array in struct ovsthread_key_slots.
+ * This key's data is stored in p1[index / L2_SIZE][index % L2_SIZE]. */
+ unsigned int index;
+};
+
+/* Per-thread data structure. */
+struct ovsthread_key_slots {
+ struct ovs_list list_node; /* In 'slots_list'. */
+ void **p1[L1_SIZE];
+};
+
+/* Contains "struct ovsthread_key_slots *". */
+static pthread_key_t tsd_key;
+
+/* Guards data structures below. */
+static struct ovs_mutex key_mutex = OVS_MUTEX_INITIALIZER;
+
+/* 'inuse_keys' holds "struct ovsthread_key"s that have been created and not
+ * yet destroyed.
+ *
+ * 'free_keys' holds "struct ovsthread_key"s that have been deleted and are
+ * ready for reuse. (We keep them around only to be able to easily locate
+ * free indexes.)
+ *
+ * Together, 'inuse_keys' and 'free_keys' hold an ovsthread_key for every index
+ * from 0 to n_keys - 1, inclusive. */
+static struct ovs_list inuse_keys OVS_GUARDED_BY(key_mutex)
+ = OVS_LIST_INITIALIZER(&inuse_keys);
+static struct ovs_list free_keys OVS_GUARDED_BY(key_mutex)
+ = OVS_LIST_INITIALIZER(&free_keys);
+static unsigned int n_keys OVS_GUARDED_BY(key_mutex);
+
+/* All existing struct ovsthread_key_slots. */
+static struct ovs_list slots_list OVS_GUARDED_BY(key_mutex)
+ = OVS_LIST_INITIALIZER(&slots_list);
+
+static void *
+clear_slot(struct ovsthread_key_slots *slots, unsigned int index)
+{
+ void **p2 = slots->p1[index / L2_SIZE];
+ if (p2) {
+ void **valuep = &p2[index % L2_SIZE];
+ void *value = *valuep;
+ *valuep = NULL;
+ return value;
+ } else {
+ return NULL;
+ }
+}
+
+static void
+ovsthread_key_destruct__(void *slots_)
+{
+ struct ovsthread_key_slots *slots = slots_;
+ struct ovsthread_key *key;
+ unsigned int n;
+ int i;
+
+ ovs_mutex_lock(&key_mutex);
+ list_remove(&slots->list_node);
+ LIST_FOR_EACH (key, list_node, &inuse_keys) {
+ void *value = clear_slot(slots, key->index);
+ if (value && key->destructor) {
+ key->destructor(value);
+ }
+ }
+ n = n_keys;
+ ovs_mutex_unlock(&key_mutex);
+
+ for (i = 0; i < DIV_ROUND_UP(n, L2_SIZE); i++) {
+ free(slots->p1[i]);
+ }
+ free(slots);
+}
+
+/* Cancels the callback to ovsthread_key_destruct__().
+ *
+ * Cancelling the call to the destructor during the main thread exit
+ * is needed while using pthreads-win32 library in Windows. It has been
+ * observed that in pthreads-win32, a call to the destructor during
+ * main thread exit causes undefined behavior. */
+static void
+ovsthread_cancel_ovsthread_key_destruct__(void *aux OVS_UNUSED)
+{
+ pthread_setspecific(tsd_key, NULL);
+}
+
+/* Initializes '*keyp' as a thread-specific data key. The data items are
+ * initially null in all threads.
+ *
+ * If a thread exits with non-null data, then 'destructor', if nonnull, will be
+ * called passing the final data value as its argument. 'destructor' must not
+ * call any thread-specific data functions in this API.
+ *
+ * This function is similar to xpthread_key_create(). */
+void
+ovsthread_key_create(ovsthread_key_t *keyp, void (*destructor)(void *))
+{
+ static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
+ struct ovsthread_key *key;
+
+ if (ovsthread_once_start(&once)) {
+ xpthread_key_create(&tsd_key, ovsthread_key_destruct__);
+ fatal_signal_add_hook(ovsthread_cancel_ovsthread_key_destruct__,
+ NULL, NULL, true);
+ ovsthread_once_done(&once);
+ }
+
+ ovs_mutex_lock(&key_mutex);
+ if (list_is_empty(&free_keys)) {
+ key = xmalloc(sizeof *key);
+ key->index = n_keys++;
+ if (key->index >= MAX_KEYS) {
+ abort();
+ }
+ } else {
+ key = CONTAINER_OF(list_pop_back(&free_keys),
+ struct ovsthread_key, list_node);
+ }
+ list_push_back(&inuse_keys, &key->list_node);
+ key->destructor = destructor;
+ ovs_mutex_unlock(&key_mutex);
+
+ *keyp = key;
+}
+
+/* Frees 'key'. The destructor supplied to ovsthread_key_create(), if any, is
+ * not called.
+ *
+ * This function is similar to xpthread_key_delete(). */
+void
+ovsthread_key_delete(ovsthread_key_t key)
+{
+ struct ovsthread_key_slots *slots;
+
+ ovs_mutex_lock(&key_mutex);
+
+ /* Move 'key' from 'inuse_keys' to 'free_keys'. */
+ list_remove(&key->list_node);
+ list_push_back(&free_keys, &key->list_node);
+
+ /* Clear this slot in all threads. */
+ LIST_FOR_EACH (slots, list_node, &slots_list) {
+ clear_slot(slots, key->index);
+ }
+
+ ovs_mutex_unlock(&key_mutex);
+}
+
+static void **
+ovsthread_key_lookup__(const struct ovsthread_key *key)
+{
+ struct ovsthread_key_slots *slots;
+ void **p2;
+
+ slots = pthread_getspecific(tsd_key);
+ if (!slots) {
+ slots = xzalloc(sizeof *slots);
+
+ ovs_mutex_lock(&key_mutex);
+ pthread_setspecific(tsd_key, slots);
+ list_push_back(&slots_list, &slots->list_node);
+ ovs_mutex_unlock(&key_mutex);
+ }
+
+ p2 = slots->p1[key->index / L2_SIZE];
+ if (!p2) {
+ p2 = xzalloc(L2_SIZE * sizeof *p2);
+ slots->p1[key->index / L2_SIZE] = p2;
+ }
+
+ return &p2[key->index % L2_SIZE];
+}
+
+/* Sets the value of thread-specific data item 'key', in the current thread, to
+ * 'value'.
+ *
+ * This function is similar to pthread_setspecific(). */
+void
+ovsthread_setspecific(ovsthread_key_t key, const void *value)
+{
+ *ovsthread_key_lookup__(key) = CONST_CAST(void *, value);
+}
+
+/* Returns the value of thread-specific data item 'key' in the current thread.
+ *
+ * This function is similar to pthread_getspecific(). */
+void *
+ovsthread_getspecific(ovsthread_key_t key)
+{
+ return *ovsthread_key_lookup__(key);
+}
#endif
projects / cascardo / ovs.git / blobdiff