[v8,07/10] eal: implement functions for mutex management

Message ID 1622849908-5710-8-git-send-email-navasile@linux.microsoft.com (mailing list archive)
State Superseded, archived
Delegated to: David Marchand
Headers
Series eal: Add EAL API for threading |

Checks

Context Check Description
ci/checkpatch warning coding style issues

Commit Message

Narcisa Ana Maria Vasile June 4, 2021, 11:38 p.m. UTC
From: Narcisa Vasile <navasile@microsoft.com>

Add functions for mutex init, destroy, lock, unlock.

On Linux, static initialization of a mutex is possible
through PTHREAD_MUTEX_INITIALIZER.

Windows does not have a static initializer.
Initialization is only done through InitializeCriticalSection().

To simulate static initialization, a fake initializator has been added:
The rte_mutex_lock() function will verify if the mutex has been initialized
using this fake initializer and if so, it will perform additional
initialization.
---
 lib/eal/common/rte_thread.c                   | 24 ++++++
 lib/eal/include/rte_thread.h                  | 53 ++++++++++++
 lib/eal/include/rte_thread_types.h            |  4 +
 .../include/rte_windows_thread_types.h        |  9 ++
 lib/eal/windows/rte_thread.c                  | 83 ++++++++++++++++++-
 5 files changed, 172 insertions(+), 1 deletion(-)
  

Patch

diff --git a/lib/eal/common/rte_thread.c b/lib/eal/common/rte_thread.c
index 84050d0f4c..4d7d9242a9 100644
--- a/lib/eal/common/rte_thread.c
+++ b/lib/eal/common/rte_thread.c
@@ -249,6 +249,30 @@  rte_thread_join(rte_thread_t thread_id, int *value_ptr)
 	return 0;
 }
 
+int
+rte_thread_mutex_init(rte_thread_mutex_t *mutex)
+{
+	return pthread_mutex_init(mutex, NULL);
+}
+
+int
+rte_thread_mutex_lock(rte_thread_mutex_t *mutex)
+{
+	return pthread_mutex_lock(mutex);
+}
+
+int
+rte_thread_mutex_unlock(rte_thread_mutex_t *mutex)
+{
+	return pthread_mutex_unlock(mutex);
+}
+
+int
+rte_thread_mutex_destroy(rte_thread_mutex_t *mutex)
+{
+	return pthread_mutex_destroy(mutex);
+}
+
 int rte_thread_cancel(rte_thread_t thread_id)
 {
 	/*
diff --git a/lib/eal/include/rte_thread.h b/lib/eal/include/rte_thread.h
index 1d481b9ad5..db8ef20930 100644
--- a/lib/eal/include/rte_thread.h
+++ b/lib/eal/include/rte_thread.h
@@ -248,6 +248,58 @@  int rte_thread_create(rte_thread_t *thread_id,
 __rte_experimental
 int rte_thread_join(rte_thread_t thread_id, int *value_ptr);
 
+/**
+ * Initializes a mutex.
+ *
+ * @param mutex
+ *    The mutex to be initialized.
+ *
+ * @return
+ *   On success, return 0.
+ *   On failure, return a positive errno-style error number.
+ */
+__rte_experimental
+int rte_thread_mutex_init(rte_thread_mutex_t *mutex);
+
+/**
+ * Locks a mutex.
+ *
+ * @param mutex
+ *    The mutex to be locked.
+ *
+ * @return
+ *   On success, return 0.
+ *   On failure, return a positive errno-style error number.
+ */
+__rte_experimental
+int rte_thread_mutex_lock(rte_thread_mutex_t *mutex);
+
+/**
+ * Unlocks a mutex.
+ *
+ * @param mutex
+ *    The mutex to be unlocked.
+ *
+ * @return
+ *   On success, return 0.
+ *   On failure, return a positive errno-style error number.
+ */
+__rte_experimental
+int rte_thread_mutex_unlock(rte_thread_mutex_t *mutex);
+
+/**
+ * Releases all resources associated with a mutex.
+ *
+ * @param mutex
+ *    The mutex to be uninitialized.
+ *
+ * @return
+ *   On success, return 0.
+ *   On failure, return a positive errno-style error number.
+ */
+__rte_experimental
+int rte_thread_mutex_destroy(rte_thread_mutex_t *mutex);
+
 /**
  * Terminates a thread.
  *
@@ -283,6 +335,7 @@  int rte_thread_detach(rte_thread_t thread_id);
  *
  * @param cpusetp
  *   Pointer to CPU affinity to set.
+ *
  * @return
  *   On success, return 0; otherwise return -1;
  */
diff --git a/lib/eal/include/rte_thread_types.h b/lib/eal/include/rte_thread_types.h
index d67b24a563..7bb0d2948c 100644
--- a/lib/eal/include/rte_thread_types.h
+++ b/lib/eal/include/rte_thread_types.h
@@ -7,4 +7,8 @@ 
 
 #include <pthread.h>
 
+#define RTE_THREAD_MUTEX_INITIALIZER     PTHREAD_MUTEX_INITIALIZER
+
+typedef pthread_mutex_t                 rte_thread_mutex_t;
+
 #endif /* _RTE_THREAD_TYPES_H_ */
diff --git a/lib/eal/windows/include/rte_windows_thread_types.h b/lib/eal/windows/include/rte_windows_thread_types.h
index 60e6d94553..c6c8502bfb 100644
--- a/lib/eal/windows/include/rte_windows_thread_types.h
+++ b/lib/eal/windows/include/rte_windows_thread_types.h
@@ -7,4 +7,13 @@ 
 
 #include <rte_windows.h>
 
+#define WINDOWS_MUTEX_INITIALIZER               (void*)-1
+#define RTE_THREAD_MUTEX_INITIALIZER            {WINDOWS_MUTEX_INITIALIZER}
+
+struct thread_mutex_t {
+	void* mutex_id;
+};
+
+typedef struct thread_mutex_t rte_thread_mutex_t;
+
 #endif /* _RTE_THREAD_TYPES_H_ */
diff --git a/lib/eal/windows/rte_thread.c b/lib/eal/windows/rte_thread.c
index 5afdd54e15..239aa6be5d 100644
--- a/lib/eal/windows/rte_thread.c
+++ b/lib/eal/windows/rte_thread.c
@@ -470,6 +470,88 @@  rte_thread_join(rte_thread_t thread_id, int *value_ptr)
 	return ret;
 }
 
+int
+rte_thread_mutex_init(rte_thread_mutex_t *mutex)
+{
+	int ret = 0;
+	CRITICAL_SECTION *m = NULL;
+
+	RTE_VERIFY(mutex != NULL);
+
+	m = calloc(1, sizeof(*m));
+	if (m == NULL) {
+		RTE_LOG(DEBUG, EAL, "Unable to initialize mutex. Insufficient memory!\n");
+		ret = ENOMEM;
+		goto cleanup;
+	}
+
+	InitializeCriticalSection(m);
+	mutex->mutex_id = m;
+	m = NULL;
+
+cleanup:
+	return ret;
+}
+
+int
+rte_thread_mutex_lock(rte_thread_mutex_t *mutex)
+{
+	int ret = 0;
+	void* id = 0;
+	rte_thread_mutex_t m;
+
+	RTE_VERIFY(mutex != NULL);
+
+	/* Check if mutex has been statically initialized */
+	id = InterlockedCompareExchangePointer(&mutex->mutex_id, mutex->mutex_id, WINDOWS_MUTEX_INITIALIZER);
+	/* If mutex has been statically initialized */
+	if (id == WINDOWS_MUTEX_INITIALIZER) {
+		ret = rte_thread_mutex_init(&m);
+		if (ret != 0) {
+			return ret;
+		}
+
+		id = InterlockedCompareExchangePointer(&mutex->mutex_id, m.mutex_id, WINDOWS_MUTEX_INITIALIZER);
+		/* If meanwhile the mutex was initialized by a different thread,
+		 * destroy the local initialization.
+		 */
+		if (id != WINDOWS_MUTEX_INITIALIZER) {
+			rte_thread_mutex_destroy(&m);
+		}
+	}
+
+	EnterCriticalSection(mutex->mutex_id);
+
+	return 0;
+}
+
+int
+rte_thread_mutex_unlock(rte_thread_mutex_t *mutex)
+{
+	RTE_VERIFY(mutex != NULL);
+
+	LeaveCriticalSection(mutex->mutex_id);
+	return 0;
+}
+
+int
+rte_thread_mutex_destroy(rte_thread_mutex_t *mutex)
+{
+	RTE_VERIFY(mutex != NULL);
+
+	if (mutex->mutex_id == WINDOWS_MUTEX_INITIALIZER) {
+		goto cleanup;
+	}
+
+	DeleteCriticalSection(mutex->mutex_id);
+	free(mutex->mutex_id);
+
+cleanup:
+	mutex->mutex_id = NULL;
+
+	return 0;
+}
+
 int
 rte_thread_cancel(rte_thread_t thread_id)
 {
@@ -549,7 +631,6 @@  rte_thread_key_delete(rte_thread_key key)
 int
 rte_thread_value_set(rte_thread_key key, const void *value)
 {
-	int ret;
 	char *p;
 
 	if (key == NULL) {