src/svm/message_queue.c - fdio/vpp - Gitiles

 /*
  * Copyright (c) 2018 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:
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include <svm/message_queue.h>
 #include <vppinfra/mem.h>
 #include <vppinfra/format.h>
 #include <sys/eventfd.h>

 static inline svm_msg_q_ring_t *
 svm_msg_q_ring_inline (svm_msg_q_t * mq, u32 ring_index)
 {
   return vec_elt_at_index (mq->rings, ring_index);
 }

 svm_msg_q_ring_t *
 svm_msg_q_ring (svm_msg_q_t * mq, u32 ring_index)
 {
   return svm_msg_q_ring_inline (mq, ring_index);
 }

 static inline void *
 svm_msg_q_ring_data (svm_msg_q_ring_t * ring, u32 elt_index)
 {
   ASSERT (elt_index < ring->nitems);
   return (ring->data + elt_index * ring->elsize);
 }

 svm_msg_q_t *
 svm_msg_q_alloc (svm_msg_q_cfg_t * cfg)
 {
   svm_msg_q_ring_cfg_t *ring_cfg;
   uword rings_sz = 0, mq_sz;
   svm_msg_q_ring_t *ring;
   u8 *base, *rings_ptr;
   vec_header_t *vh;
   u32 vec_sz, q_sz;
   svm_msg_q_t *mq;
   int i;

   ASSERT (cfg);

   vec_sz = vec_header_bytes (0) + sizeof (svm_msg_q_ring_t) * cfg->n_rings;
   for (i = 0; i < cfg->n_rings; i++)
     {
       if (cfg->ring_cfgs[i].data)
 	continue;
       ring_cfg = &cfg->ring_cfgs[i];
       rings_sz += (uword) ring_cfg->nitems * ring_cfg->elsize;
     }

   q_sz = sizeof (svm_queue_t) + cfg->q_nitems * sizeof (svm_msg_q_msg_t);
   mq_sz = sizeof (svm_msg_q_t) + vec_sz + rings_sz + q_sz;
   base = clib_mem_alloc_aligned (mq_sz, CLIB_CACHE_LINE_BYTES);
   if (!base)
     return 0;

   mq = (svm_msg_q_t *) base;
   mq->q = svm_queue_init (base + sizeof (svm_msg_q_t), cfg->q_nitems,
 			  sizeof (svm_msg_q_msg_t));
   mq->q->consumer_pid = cfg->consumer_pid;
   vh = (vec_header_t *) ((u8 *) mq->q + q_sz);
   vh->len = cfg->n_rings;
   mq->rings = (svm_msg_q_ring_t *) (vh + 1);
   rings_ptr = (u8 *) mq->rings + sizeof (svm_msg_q_ring_t) * cfg->n_rings;
   for (i = 0; i < cfg->n_rings; i++)
     {
       ring = &mq->rings[i];
       ring->elsize = cfg->ring_cfgs[i].elsize;
       ring->nitems = cfg->ring_cfgs[i].nitems;
       ring->cursize = ring->head = ring->tail = 0;
       if (cfg->ring_cfgs[i].data)
 	ring->data = cfg->ring_cfgs[i].data;
       else
 	{
 	  ring->data = rings_ptr;
 	  rings_ptr += (uword) ring->nitems * ring->elsize;
 	}
     }

   return mq;
 }

 void
 svm_msg_q_free (svm_msg_q_t * mq)
 {
   svm_queue_free (mq->q);
   clib_mem_free (mq);
 }

 svm_msg_q_msg_t
 svm_msg_q_alloc_msg_w_ring (svm_msg_q_t * mq, u32 ring_index)
 {
   svm_msg_q_msg_t msg;
   svm_msg_q_ring_t *ring = svm_msg_q_ring_inline (mq, ring_index);

   ASSERT (ring->cursize < ring->nitems);
   msg.ring_index = ring - mq->rings;
   msg.elt_index = ring->tail;
   ring->tail = (ring->tail + 1) % ring->nitems;
   clib_atomic_fetch_add (&ring->cursize, 1);
   return msg;
 }

 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)
 {
   if (noblock)
     {
       if (svm_msg_q_try_lock (mq))
 	return -1;
       if (PREDICT_FALSE (svm_msg_q_is_full (mq)
 			 || svm_msg_q_ring_is_full (mq, ring_index)))
 	{
 	  svm_msg_q_unlock (mq);
 	  return -2;
 	}
       *msg = svm_msg_q_alloc_msg_w_ring (mq, ring_index);
     }
   else
     {
       svm_msg_q_lock (mq);
       while (svm_msg_q_is_full (mq)
 	     || svm_msg_q_ring_is_full (mq, ring_index))
 	svm_msg_q_wait (mq);
       *msg = svm_msg_q_alloc_msg_w_ring (mq, ring_index);
     }
   return 0;
 }

 svm_msg_q_msg_t
 svm_msg_q_alloc_msg (svm_msg_q_t * mq, u32 nbytes)
 {
   svm_msg_q_msg_t msg = {.as_u64 = ~0 };
   svm_msg_q_ring_t *ring;

   vec_foreach (ring, mq->rings)
   {
     if (ring->elsize < nbytes || ring->cursize == ring->nitems)
       continue;
     msg.ring_index = ring - mq->rings;
     msg.elt_index = ring->tail;
     ring->tail = (ring->tail + 1) % ring->nitems;
     clib_atomic_fetch_add (&ring->cursize, 1);
     break;
   }
   return msg;
 }

 void *
 svm_msg_q_msg_data (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
 {
   svm_msg_q_ring_t *ring = svm_msg_q_ring_inline (mq, msg->ring_index);
   return svm_msg_q_ring_data (ring, msg->elt_index);
 }

 void
 svm_msg_q_free_msg (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
 {
   svm_msg_q_ring_t *ring;

   ASSERT (vec_len (mq->rings) > msg->ring_index);
   ring = &mq->rings[msg->ring_index];
   if (msg->elt_index == ring->head)
     {
       ring->head = (ring->head + 1) % ring->nitems;
     }
   else
     {
       clib_warning ("message out of order");
       /* for now, expect messages to be processed in order */
       ASSERT (0);
     }
   clib_atomic_fetch_sub (&ring->cursize, 1);
 }

 static int
 svm_msq_q_msg_is_valid (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
 {
   u32 dist1, dist2, tail, head;
   svm_msg_q_ring_t *ring;

   if (vec_len (mq->rings) <= msg->ring_index)
     return 0;
   ring = &mq->rings[msg->ring_index];
   tail = ring->tail;
   head = ring->head;

   dist1 = ((ring->nitems + msg->elt_index) - head) % ring->nitems;
   if (tail == head)
     dist2 = (ring->cursize == 0) ? 0 : ring->nitems;
   else
     dist2 = ((ring->nitems + tail) - head) % ring->nitems;
   return (dist1 < dist2);
 }

 int
 svm_msg_q_add (svm_msg_q_t * mq, svm_msg_q_msg_t * msg, int nowait)
 {
   ASSERT (svm_msq_q_msg_is_valid (mq, msg));
   return svm_queue_add (mq->q, (u8 *) msg, nowait);
 }

 void
 svm_msg_q_add_and_unlock (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
 {
   ASSERT (svm_msq_q_msg_is_valid (mq, msg));
   svm_queue_add_raw (mq->q, (u8 *) msg);
   svm_msg_q_unlock (mq);
 }

 int
 svm_msg_q_sub (svm_msg_q_t * mq, svm_msg_q_msg_t * msg,
 	       svm_q_conditional_wait_t cond, u32 time)
 {
   return svm_queue_sub (mq->q, (u8 *) msg, cond, time);
 }

 void
 svm_msg_q_sub_w_lock (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
 {
   svm_queue_sub_raw (mq->q, (u8 *) msg);
 }

 void
 svm_msg_q_set_consumer_eventfd (svm_msg_q_t * mq, int fd)
 {
   mq->q->consumer_evtfd = fd;
 }

 void
 svm_msg_q_set_producer_eventfd (svm_msg_q_t * mq, int fd)
 {
   mq->q->producer_evtfd = fd;
 }

 int
 svm_msg_q_alloc_consumer_eventfd (svm_msg_q_t * mq)
 {
   int fd;
   if ((fd = eventfd (0, EFD_NONBLOCK)) < 0)
     return -1;
   svm_msg_q_set_consumer_eventfd (mq, fd);
   return 0;
 }

 int
 svm_msg_q_alloc_producer_eventfd (svm_msg_q_t * mq)
 {
   int fd;
   if ((fd = eventfd (0, EFD_NONBLOCK)) < 0)
     return -1;
   svm_msg_q_set_producer_eventfd (mq, fd);
   return 0;
 }

 u8 *
 format_svm_msg_q (u8 * s, va_list * args)
 {
   svm_msg_q_t *mq = va_arg (*args, svm_msg_q_t *);
   s = format (s, " [Q:%d/%d]", mq->q->cursize, mq->q->maxsize);
   for (u32 i = 0; i < vec_len (mq->rings); i++)
     {
       s = format (s, " [R%d:%d/%d]", i, mq->rings[i].cursize,
 		  mq->rings[i].nitems);
     }
   return s;
 }

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* Copyright (c) 2018 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:
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include <svm/message_queue.h>
	#include <vppinfra/mem.h>
	#include <vppinfra/format.h>
	#include <sys/eventfd.h>

	static inline svm_msg_q_ring_t *
	svm_msg_q_ring_inline (svm_msg_q_t * mq, u32 ring_index)
	{
	return vec_elt_at_index (mq->rings, ring_index);
	}

	svm_msg_q_ring_t *
	svm_msg_q_ring (svm_msg_q_t * mq, u32 ring_index)
	{
	return svm_msg_q_ring_inline (mq, ring_index);
	}

	static inline void *
	svm_msg_q_ring_data (svm_msg_q_ring_t * ring, u32 elt_index)
	{
	ASSERT (elt_index < ring->nitems);
	return (ring->data + elt_index * ring->elsize);
	}

	svm_msg_q_t *
	svm_msg_q_alloc (svm_msg_q_cfg_t * cfg)
	{
	svm_msg_q_ring_cfg_t *ring_cfg;
	uword rings_sz = 0, mq_sz;
	svm_msg_q_ring_t *ring;
	u8 base, rings_ptr;
	vec_header_t *vh;
	u32 vec_sz, q_sz;
	svm_msg_q_t *mq;
	int i;

	ASSERT (cfg);

	vec_sz = vec_header_bytes (0) + sizeof (svm_msg_q_ring_t) * cfg->n_rings;
	for (i = 0; i < cfg->n_rings; i++)
	{
	if (cfg->ring_cfgs[i].data)
	continue;
	ring_cfg = &cfg->ring_cfgs[i];
	rings_sz += (uword) ring_cfg->nitems * ring_cfg->elsize;
	}

	q_sz = sizeof (svm_queue_t) + cfg->q_nitems * sizeof (svm_msg_q_msg_t);
	mq_sz = sizeof (svm_msg_q_t) + vec_sz + rings_sz + q_sz;
	base = clib_mem_alloc_aligned (mq_sz, CLIB_CACHE_LINE_BYTES);
	if (!base)
	return 0;

	mq = (svm_msg_q_t *) base;
	mq->q = svm_queue_init (base + sizeof (svm_msg_q_t), cfg->q_nitems,
	sizeof (svm_msg_q_msg_t));
	mq->q->consumer_pid = cfg->consumer_pid;
	vh = (vec_header_t ) ((u8 ) mq->q + q_sz);
	vh->len = cfg->n_rings;
	mq->rings = (svm_msg_q_ring_t *) (vh + 1);
	rings_ptr = (u8 ) mq->rings + sizeof (svm_msg_q_ring_t) cfg->n_rings;
	for (i = 0; i < cfg->n_rings; i++)
	{
	ring = &mq->rings[i];
	ring->elsize = cfg->ring_cfgs[i].elsize;
	ring->nitems = cfg->ring_cfgs[i].nitems;
	ring->cursize = ring->head = ring->tail = 0;
	if (cfg->ring_cfgs[i].data)
	ring->data = cfg->ring_cfgs[i].data;
	else
	{
	ring->data = rings_ptr;
	rings_ptr += (uword) ring->nitems * ring->elsize;
	}
	}

	return mq;
	}

	void
	svm_msg_q_free (svm_msg_q_t * mq)
	{
	svm_queue_free (mq->q);
	clib_mem_free (mq);
	}

	svm_msg_q_msg_t
	svm_msg_q_alloc_msg_w_ring (svm_msg_q_t * mq, u32 ring_index)
	{
	svm_msg_q_msg_t msg;
	svm_msg_q_ring_t *ring = svm_msg_q_ring_inline (mq, ring_index);

	ASSERT (ring->cursize < ring->nitems);
	msg.ring_index = ring - mq->rings;
	msg.elt_index = ring->tail;
	ring->tail = (ring->tail + 1) % ring->nitems;
	clib_atomic_fetch_add (&ring->cursize, 1);
	return msg;
	}

	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)
	{
	if (noblock)
	{
	if (svm_msg_q_try_lock (mq))
	return -1;
	if (PREDICT_FALSE (svm_msg_q_is_full (mq)
	\|\| svm_msg_q_ring_is_full (mq, ring_index)))
	{
	svm_msg_q_unlock (mq);
	return -2;
	}
	*msg = svm_msg_q_alloc_msg_w_ring (mq, ring_index);
	}
	else
	{
	svm_msg_q_lock (mq);
	while (svm_msg_q_is_full (mq)
	\|\| svm_msg_q_ring_is_full (mq, ring_index))
	svm_msg_q_wait (mq);
	*msg = svm_msg_q_alloc_msg_w_ring (mq, ring_index);
	}
	return 0;
	}

	svm_msg_q_msg_t
	svm_msg_q_alloc_msg (svm_msg_q_t * mq, u32 nbytes)
	{
	svm_msg_q_msg_t msg = {.as_u64 = ~0 };
	svm_msg_q_ring_t *ring;

	vec_foreach (ring, mq->rings)
	{
	if (ring->elsize < nbytes \|\| ring->cursize == ring->nitems)
	continue;
	msg.ring_index = ring - mq->rings;
	msg.elt_index = ring->tail;
	ring->tail = (ring->tail + 1) % ring->nitems;
	clib_atomic_fetch_add (&ring->cursize, 1);
	break;
	}
	return msg;
	}

	void *
	svm_msg_q_msg_data (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
	{
	svm_msg_q_ring_t *ring = svm_msg_q_ring_inline (mq, msg->ring_index);
	return svm_msg_q_ring_data (ring, msg->elt_index);
	}

	void
	svm_msg_q_free_msg (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
	{
	svm_msg_q_ring_t *ring;

	ASSERT (vec_len (mq->rings) > msg->ring_index);
	ring = &mq->rings[msg->ring_index];
	if (msg->elt_index == ring->head)
	{
	ring->head = (ring->head + 1) % ring->nitems;
	}
	else
	{
	clib_warning ("message out of order");
	/* for now, expect messages to be processed in order */
	ASSERT (0);
	}
	clib_atomic_fetch_sub (&ring->cursize, 1);
	}

	static int
	svm_msq_q_msg_is_valid (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
	{
	u32 dist1, dist2, tail, head;
	svm_msg_q_ring_t *ring;

	if (vec_len (mq->rings) <= msg->ring_index)
	return 0;
	ring = &mq->rings[msg->ring_index];
	tail = ring->tail;
	head = ring->head;

	dist1 = ((ring->nitems + msg->elt_index) - head) % ring->nitems;
	if (tail == head)
	dist2 = (ring->cursize == 0) ? 0 : ring->nitems;
	else
	dist2 = ((ring->nitems + tail) - head) % ring->nitems;
	return (dist1 < dist2);
	}

	int
	svm_msg_q_add (svm_msg_q_t * mq, svm_msg_q_msg_t * msg, int nowait)
	{
	ASSERT (svm_msq_q_msg_is_valid (mq, msg));
	return svm_queue_add (mq->q, (u8 *) msg, nowait);
	}

	void
	svm_msg_q_add_and_unlock (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
	{
	ASSERT (svm_msq_q_msg_is_valid (mq, msg));
	svm_queue_add_raw (mq->q, (u8 *) msg);
	svm_msg_q_unlock (mq);
	}

	int
	svm_msg_q_sub (svm_msg_q_t * mq, svm_msg_q_msg_t * msg,
	svm_q_conditional_wait_t cond, u32 time)
	{
	return svm_queue_sub (mq->q, (u8 *) msg, cond, time);
	}

	void
	svm_msg_q_sub_w_lock (svm_msg_q_t * mq, svm_msg_q_msg_t * msg)
	{
	svm_queue_sub_raw (mq->q, (u8 *) msg);
	}

	void
	svm_msg_q_set_consumer_eventfd (svm_msg_q_t * mq, int fd)
	{
	mq->q->consumer_evtfd = fd;
	}

	void
	svm_msg_q_set_producer_eventfd (svm_msg_q_t * mq, int fd)
	{
	mq->q->producer_evtfd = fd;
	}

	int
	svm_msg_q_alloc_consumer_eventfd (svm_msg_q_t * mq)
	{
	int fd;
	if ((fd = eventfd (0, EFD_NONBLOCK)) < 0)
	return -1;
	svm_msg_q_set_consumer_eventfd (mq, fd);
	return 0;
	}

	int
	svm_msg_q_alloc_producer_eventfd (svm_msg_q_t * mq)
	{
	int fd;
	if ((fd = eventfd (0, EFD_NONBLOCK)) < 0)
	return -1;
	svm_msg_q_set_producer_eventfd (mq, fd);
	return 0;
	}

	u8 *
	format_svm_msg_q (u8 * s, va_list * args)
	{
	svm_msg_q_t mq = va_arg (args, svm_msg_q_t *);
	s = format (s, " [Q:%d/%d]", mq->q->cursize, mq->q->maxsize);
	for (u32 i = 0; i < vec_len (mq->rings); i++)
	{
	s = format (s, " [R%d:%d/%d]", i, mq->rings[i].cursize,
	mq->rings[i].nitems);
	}
	return s;
	}

	/*
	* fd.io coding-style-patch-verification: ON
	*
	* Local Variables:
	* eval: (c-set-style "gnu")
	* End:
	*/