/*
- * Copyright (c) 2018 Cisco and/or its affiliates.
+ * Copyright (c) 2018-2019 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
#define SRC_SVM_MESSAGE_QUEUE_H_
#include <vppinfra/clib.h>
+#include <vppinfra/error.h>
#include <svm/queue.h>
-typedef struct svm_msg_q_ring_
+typedef struct svm_msg_q_ring_shared_
{
volatile u32 cursize; /**< current size of the ring */
u32 nitems; /**< max size of the ring */
- u32 head; /**< current head (for dequeue) */
- u32 tail; /**< current tail (for enqueue) */
+ volatile u32 head; /**< current head (for dequeue) */
+ volatile u32 tail; /**< current tail (for enqueue) */
u32 elsize; /**< size of an element */
- u8 *data; /**< chunk of memory for msg data */
-} svm_msg_q_ring_t;
+ u8 data[0]; /**< chunk of memory for msg data */
+} svm_msg_q_ring_shared_t;
+
+typedef struct svm_msg_q_ring_
+{
+ u32 nitems; /**< max size of the ring */
+ u32 elsize; /**< size of an element */
+ svm_msg_q_ring_shared_t *shr; /**< ring in shared memory */
+} __clib_packed svm_msg_q_ring_t;
+
+typedef struct svm_msg_q_shared_
+{
+ u32 n_rings; /**< number of rings after q */
+ u32 pad; /**< 8 byte alignment for q */
+ svm_queue_t q[0]; /**< queue for exchanging messages */
+} __clib_packed svm_msg_q_shared_t;
typedef struct svm_msg_q_
{
svm_queue_t *q; /**< queue for exchanging messages */
svm_msg_q_ring_t *rings; /**< rings with message data*/
-} svm_msg_q_t;
+} __clib_packed svm_msg_q_t;
typedef struct svm_msg_q_ring_cfg_
{
u64 as_u64;
} svm_msg_q_msg_t;
+#define SVM_MQ_INVALID_MSG { .as_u64 = ~0 }
/**
* Allocate message queue
*
* ring configs
* @return message queue
*/
-svm_msg_q_t *svm_msg_q_alloc (svm_msg_q_cfg_t * cfg);
+svm_msg_q_shared_t *svm_msg_q_alloc (svm_msg_q_cfg_t *cfg);
+svm_msg_q_shared_t *svm_msg_q_init (void *base, svm_msg_q_cfg_t *cfg);
+uword svm_msg_q_size_to_alloc (svm_msg_q_cfg_t *cfg);
+
+void svm_msg_q_attach (svm_msg_q_t *mq, void *smq_base);
/**
* Free message queue
*/
svm_msg_q_msg_t svm_msg_q_alloc_msg (svm_msg_q_t * mq, u32 nbytes);
+/**
+ * Allocate message buffer on ring
+ *
+ * Message is allocated, on requested ring. The caller MUST check that
+ * the ring is not full.
+ *
+ * @param mq message queue
+ * @param ring_index ring on which the allocation should occur
+ * @return message structure pointing to the ring and position
+ * allocated
+ */
+svm_msg_q_msg_t svm_msg_q_alloc_msg_w_ring (svm_msg_q_t * mq, u32 ring_index);
+
+/**
+ * Lock message queue and allocate message buffer on ring
+ *
+ * This should be used when multiple writers/readers are expected to
+ * compete for the rings/queue. Message should be enqueued by calling
+ * @ref svm_msg_q_add_w_lock and the caller MUST unlock the queue once
+ * the message in enqueued.
+ *
+ * @param mq message queue
+ * @param ring_index ring on which the allocation should occur
+ * @param noblock flag that indicates if request should block
+ * @param msg pointer to message to be filled in
+ * @return 0 on success, negative number otherwise
+ */
+int svm_msg_q_lock_and_alloc_msg_w_ring (svm_msg_q_t * mq, u32 ring_index,
+ u8 noblock, svm_msg_q_msg_t * msg);
+
/**
* Free message buffer
*
* @param msg message to be freed
*/
void svm_msg_q_free_msg (svm_msg_q_t * mq, svm_msg_q_msg_t * msg);
+
/**
* Producer enqueue one message to queue
*
* @param nowait flag to indicate if request is blocking or not
* @return success status
*/
-int svm_msg_q_add (svm_msg_q_t * mq, svm_msg_q_msg_t msg, int nowait);
+int svm_msg_q_add (svm_msg_q_t * mq, svm_msg_q_msg_t * msg, int nowait);
+
+/**
+ * Producer enqueue one message to queue with mutex held
+ *
+ * Prior to calling this, the producer should've obtained a message buffer
+ * from one of the rings by calling @ref svm_msg_q_alloc_msg. It assumes
+ * the queue mutex is held.
+ *
+ * @param mq message queue
+ * @param msg message (pointer to ring position) to be enqueued
+ * @return success status
+ */
+void svm_msg_q_add_and_unlock (svm_msg_q_t * mq, svm_msg_q_msg_t * msg);
/**
* Consumer dequeue one message from queue
* @param mq message queue
* @param msg pointer to structure where message is to be received
* @param cond flag that indicates if request should block or not
+ * @param time time to wait if condition it SVM_Q_TIMEDWAIT
* @return success status
*/
int svm_msg_q_sub (svm_msg_q_t * mq, svm_msg_q_msg_t * msg,
svm_q_conditional_wait_t cond, u32 time);
/**
- * Get data for message in queu
+ * Consumer dequeue one message from queue with mutex held
+ *
+ * Returns the message pointing to the data in the message rings under the
+ * assumption that the message queue lock is already held. The consumer is
+ * expected to call @ref svm_msg_q_free_msg once it finishes
+ * processing/copies the message data.
+ *
+ * @param mq message queue
+ * @param msg pointer to structure where message is to be received
+ * @return success status
+ */
+void svm_msg_q_sub_w_lock (svm_msg_q_t * mq, svm_msg_q_msg_t * msg);
+
+/**
+ * Get data for message in queue
*
* @param mq message queue
* @param msg message for which the data is requested
*/
void *svm_msg_q_msg_data (svm_msg_q_t * mq, svm_msg_q_msg_t * msg);
+/**
+ * Get message queue ring
+ *
+ * @param mq message queue
+ * @param ring_index index of ring
+ * @return pointer to ring
+ */
+svm_msg_q_ring_t *svm_msg_q_ring (svm_msg_q_t * mq, u32 ring_index);
+
+/**
+ * Set event fd for queue consumer
+ *
+ * If set, queue will exclusively use eventfds for signaling. Moreover,
+ * afterwards, the queue should only be used in non-blocking mode. Waiting
+ * for events should be done externally using something like epoll.
+ *
+ * @param mq message queue
+ * @param fd consumer eventfd
+ */
+void svm_msg_q_set_consumer_eventfd (svm_msg_q_t * mq, int fd);
+
+/**
+ * Set event fd for queue producer
+ *
+ * If set, queue will exclusively use eventfds for signaling. Moreover,
+ * afterwards, the queue should only be used in non-blocking mode. Waiting
+ * for events should be done externally using something like epoll.
+ *
+ * @param mq message queue
+ * @param fd producer eventfd
+ */
+void svm_msg_q_set_producer_eventfd (svm_msg_q_t * mq, int fd);
+
+/**
+ * Allocate event fd for queue consumer
+ */
+int svm_msg_q_alloc_consumer_eventfd (svm_msg_q_t * mq);
+
+/**
+ * Allocate event fd for queue consumer
+ */
+int svm_msg_q_alloc_producer_eventfd (svm_msg_q_t * mq);
+
+
+/**
+ * Format message queue, shows msg count for each ring
+ */
+u8 *format_svm_msg_q (u8 * s, va_list * args);
+
+/**
+ * Check if message queue is full
+ */
+static inline u8
+svm_msg_q_is_full (svm_msg_q_t * mq)
+{
+ return (mq->q->cursize == mq->q->maxsize);
+}
+
+static inline u8
+svm_msg_q_ring_is_full (svm_msg_q_t * mq, u32 ring_index)
+{
+ svm_msg_q_ring_t *ring = vec_elt_at_index (mq->rings, ring_index);
+ return (ring->shr->cursize >= ring->nitems);
+}
+
+/**
+ * Check if message queue is empty
+ */
+static inline u8
+svm_msg_q_is_empty (svm_msg_q_t * mq)
+{
+ return (mq->q->cursize == 0);
+}
+
+/**
+ * Check length of message queue
+ */
+static inline u32
+svm_msg_q_size (svm_msg_q_t * mq)
+{
+ return mq->q->cursize;
+}
+
+/**
+ * Check if message is invalid
+ */
+static inline u8
+svm_msg_q_msg_is_invalid (svm_msg_q_msg_t * msg)
+{
+ return (msg->as_u64 == (u64) ~ 0);
+}
+
+/**
+ * Try locking message queue
+ */
+static inline int
+svm_msg_q_try_lock (svm_msg_q_t * mq)
+{
+ int rv = pthread_mutex_trylock (&mq->q->mutex);
+ if (PREDICT_FALSE (rv == EOWNERDEAD))
+ rv = pthread_mutex_consistent (&mq->q->mutex);
+ return rv;
+}
+
+/**
+ * Lock, or block trying, the message queue
+ */
+static inline int
+svm_msg_q_lock (svm_msg_q_t * mq)
+{
+ int rv = pthread_mutex_lock (&mq->q->mutex);
+ if (PREDICT_FALSE (rv == EOWNERDEAD))
+ rv = pthread_mutex_consistent (&mq->q->mutex);
+ return rv;
+}
+
+/**
+ * Unlock message queue
+ */
+static inline void
+svm_msg_q_unlock (svm_msg_q_t * mq)
+{
+ pthread_mutex_unlock (&mq->q->mutex);
+}
+
+/**
+ * Wait for message queue event
+ *
+ * Must be called with mutex held. The queue only works non-blocking
+ * with eventfds, so handle blocking calls as an exception here.
+ */
+static inline void
+svm_msg_q_wait (svm_msg_q_t * mq)
+{
+ svm_queue_wait (mq->q);
+}
+
+/**
+ * Timed wait for message queue event
+ *
+ * Must be called with mutex held.
+ *
+ * @param mq message queue
+ * @param timeout time in seconds
+ */
+static inline int
+svm_msg_q_timedwait (svm_msg_q_t * mq, double timeout)
+{
+ return svm_queue_timedwait (mq->q, timeout);
+}
+
+static inline int
+svm_msg_q_get_consumer_eventfd (svm_msg_q_t * mq)
+{
+ return mq->q->consumer_evtfd;
+}
+
+static inline int
+svm_msg_q_get_producer_eventfd (svm_msg_q_t * mq)
+{
+ return mq->q->producer_evtfd;
+}
+
#endif /* SRC_SVM_MESSAGE_QUEUE_H_ */
/*
Code Review / vpp.git / blobdiff