eal: add IPC asynchronous request

This API is similar to the blocking API that is already present,
but reply will be received in a separate callback by the caller
(callback specified at the time of request, rather than registering
for it in advance).

Under the hood, we create a separate thread to deal with replies to
asynchronous requests, that will just wait to be notified by the
main thread, or woken up on a timer.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Jianfeng Tan <jianfeng.tan@intel.com>
This commit is contained in:
Anatoly Burakov 2018-03-31 18:06:16 +01:00 committed by Thomas Monjalon
parent ce3a731235
commit f05e26051c
3 changed files with 482 additions and 13 deletions

View File

@ -26,6 +26,7 @@
#include <rte_errno.h> #include <rte_errno.h>
#include <rte_lcore.h> #include <rte_lcore.h>
#include <rte_log.h> #include <rte_log.h>
#include <rte_tailq.h>
#include "eal_private.h" #include "eal_private.h"
#include "eal_filesystem.h" #include "eal_filesystem.h"
@ -60,13 +61,32 @@ struct mp_msg_internal {
struct rte_mp_msg msg; struct rte_mp_msg msg;
}; };
struct async_request_param {
rte_mp_async_reply_t clb;
struct rte_mp_reply user_reply;
struct timespec end;
int n_responses_processed;
};
struct pending_request { struct pending_request {
TAILQ_ENTRY(pending_request) next; TAILQ_ENTRY(pending_request) next;
int reply_received; enum {
REQUEST_TYPE_SYNC,
REQUEST_TYPE_ASYNC
} type;
char dst[PATH_MAX]; char dst[PATH_MAX];
struct rte_mp_msg *request; struct rte_mp_msg *request;
struct rte_mp_msg *reply; struct rte_mp_msg *reply;
pthread_cond_t cond; int reply_received;
RTE_STD_C11
union {
struct {
struct async_request_param *param;
} async;
struct {
pthread_cond_t cond;
} sync;
};
}; };
TAILQ_HEAD(pending_request_list, pending_request); TAILQ_HEAD(pending_request_list, pending_request);
@ -74,9 +94,12 @@ TAILQ_HEAD(pending_request_list, pending_request);
static struct { static struct {
struct pending_request_list requests; struct pending_request_list requests;
pthread_mutex_t lock; pthread_mutex_t lock;
pthread_cond_t async_cond;
} pending_requests = { } pending_requests = {
.requests = TAILQ_HEAD_INITIALIZER(pending_requests.requests), .requests = TAILQ_HEAD_INITIALIZER(pending_requests.requests),
.lock = PTHREAD_MUTEX_INITIALIZER .lock = PTHREAD_MUTEX_INITIALIZER,
.async_cond = PTHREAD_COND_INITIALIZER
/**< used in async requests only */
}; };
/* forward declarations */ /* forward declarations */
@ -273,7 +296,12 @@ process_msg(struct mp_msg_internal *m, struct sockaddr_un *s)
memcpy(sync_req->reply, msg, sizeof(*msg)); memcpy(sync_req->reply, msg, sizeof(*msg));
/* -1 indicates that we've been asked to ignore */ /* -1 indicates that we've been asked to ignore */
sync_req->reply_received = m->type == MP_REP ? 1 : -1; sync_req->reply_received = m->type == MP_REP ? 1 : -1;
pthread_cond_signal(&sync_req->cond);
if (sync_req->type == REQUEST_TYPE_SYNC)
pthread_cond_signal(&sync_req->sync.cond);
else if (sync_req->type == REQUEST_TYPE_ASYNC)
pthread_cond_signal(
&pending_requests.async_cond);
} else } else
RTE_LOG(ERR, EAL, "Drop mp reply: %s\n", msg->name); RTE_LOG(ERR, EAL, "Drop mp reply: %s\n", msg->name);
pthread_mutex_unlock(&pending_requests.lock); pthread_mutex_unlock(&pending_requests.lock);
@ -319,6 +347,189 @@ mp_handle(void *arg __rte_unused)
return NULL; return NULL;
} }
static int
timespec_cmp(const struct timespec *a, const struct timespec *b)
{
if (a->tv_sec < b->tv_sec)
return -1;
if (a->tv_sec > b->tv_sec)
return 1;
if (a->tv_nsec < b->tv_nsec)
return -1;
if (a->tv_nsec > b->tv_nsec)
return 1;
return 0;
}
enum async_action {
ACTION_NONE, /**< don't do anything */
ACTION_FREE, /**< free the action entry, but don't trigger callback */
ACTION_TRIGGER /**< trigger callback, then free action entry */
};
static enum async_action
process_async_request(struct pending_request *sr, const struct timespec *now)
{
struct async_request_param *param;
struct rte_mp_reply *reply;
bool timeout, received, last_msg;
param = sr->async.param;
reply = &param->user_reply;
/* did we timeout? */
timeout = timespec_cmp(&param->end, now) <= 0;
/* did we receive a response? */
received = sr->reply_received != 0;
/* if we didn't time out, and we didn't receive a response, ignore */
if (!timeout && !received)
return ACTION_NONE;
/* if we received a response, adjust relevant data and copy mesasge. */
if (sr->reply_received == 1 && sr->reply) {
struct rte_mp_msg *msg, *user_msgs, *tmp;
msg = sr->reply;
user_msgs = reply->msgs;
tmp = realloc(user_msgs, sizeof(*msg) *
(reply->nb_received + 1));
if (!tmp) {
RTE_LOG(ERR, EAL, "Fail to alloc reply for request %s:%s\n",
sr->dst, sr->request->name);
/* this entry is going to be removed and its message
* dropped, but we don't want to leak memory, so
* continue.
*/
} else {
user_msgs = tmp;
reply->msgs = user_msgs;
memcpy(&user_msgs[reply->nb_received],
msg, sizeof(*msg));
reply->nb_received++;
}
/* mark this request as processed */
param->n_responses_processed++;
} else if (sr->reply_received == -1) {
/* we were asked to ignore this process */
reply->nb_sent--;
}
free(sr->reply);
last_msg = param->n_responses_processed == reply->nb_sent;
return last_msg ? ACTION_TRIGGER : ACTION_FREE;
}
static void
trigger_async_action(struct pending_request *sr)
{
struct async_request_param *param;
struct rte_mp_reply *reply;
param = sr->async.param;
reply = &param->user_reply;
param->clb(sr->request, reply);
/* clean up */
free(sr->async.param->user_reply.msgs);
free(sr->async.param);
free(sr->request);
}
static void *
async_reply_handle(void *arg __rte_unused)
{
struct pending_request *sr;
struct timeval now;
struct timespec timeout, ts_now;
while (1) {
struct pending_request *trigger = NULL;
int ret;
bool nowait = false;
bool timedwait = false;
pthread_mutex_lock(&pending_requests.lock);
/* scan through the list and see if there are any timeouts that
* are earlier than our current timeout.
*/
TAILQ_FOREACH(sr, &pending_requests.requests, next) {
if (sr->type != REQUEST_TYPE_ASYNC)
continue;
if (!timedwait || timespec_cmp(&sr->async.param->end,
&timeout) < 0) {
memcpy(&timeout, &sr->async.param->end,
sizeof(timeout));
timedwait = true;
}
/* sometimes, we don't even wait */
if (sr->reply_received) {
nowait = true;
break;
}
}
if (nowait)
ret = 0;
else if (timedwait)
ret = pthread_cond_timedwait(
&pending_requests.async_cond,
&pending_requests.lock, &timeout);
else
ret = pthread_cond_wait(&pending_requests.async_cond,
&pending_requests.lock);
if (gettimeofday(&now, NULL) < 0) {
RTE_LOG(ERR, EAL, "Cannot get current time\n");
break;
}
ts_now.tv_nsec = now.tv_usec * 1000;
ts_now.tv_sec = now.tv_sec;
if (ret == 0 || ret == ETIMEDOUT) {
struct pending_request *next;
/* we've either been woken up, or we timed out */
/* we have still the lock, check if anything needs
* processing.
*/
TAILQ_FOREACH_SAFE(sr, &pending_requests.requests, next,
next) {
enum async_action action;
if (sr->type != REQUEST_TYPE_ASYNC)
continue;
action = process_async_request(sr, &ts_now);
if (action == ACTION_FREE) {
TAILQ_REMOVE(&pending_requests.requests,
sr, next);
free(sr);
} else if (action == ACTION_TRIGGER &&
trigger == NULL) {
TAILQ_REMOVE(&pending_requests.requests,
sr, next);
trigger = sr;
}
}
}
pthread_mutex_unlock(&pending_requests.lock);
if (trigger) {
trigger_async_action(trigger);
free(trigger);
}
};
RTE_LOG(ERR, EAL, "ERROR: asynchronous requests disabled\n");
return NULL;
}
static int static int
open_socket_fd(void) open_socket_fd(void)
{ {
@ -382,7 +593,7 @@ rte_mp_channel_init(void)
char thread_name[RTE_MAX_THREAD_NAME_LEN]; char thread_name[RTE_MAX_THREAD_NAME_LEN];
char path[PATH_MAX]; char path[PATH_MAX];
int dir_fd; int dir_fd;
pthread_t tid; pthread_t mp_handle_tid, async_reply_handle_tid;
/* create filter path */ /* create filter path */
create_socket_path("*", path, sizeof(path)); create_socket_path("*", path, sizeof(path));
@ -419,7 +630,16 @@ rte_mp_channel_init(void)
return -1; return -1;
} }
if (pthread_create(&tid, NULL, mp_handle, NULL) < 0) { if (pthread_create(&mp_handle_tid, NULL, mp_handle, NULL) < 0) {
RTE_LOG(ERR, EAL, "failed to create mp thead: %s\n",
strerror(errno));
close(mp_fd);
mp_fd = -1;
return -1;
}
if (pthread_create(&async_reply_handle_tid, NULL,
async_reply_handle, NULL) < 0) {
RTE_LOG(ERR, EAL, "failed to create mp thead: %s\n", RTE_LOG(ERR, EAL, "failed to create mp thead: %s\n",
strerror(errno)); strerror(errno));
close(mp_fd); close(mp_fd);
@ -430,7 +650,11 @@ rte_mp_channel_init(void)
/* try best to set thread name */ /* try best to set thread name */
snprintf(thread_name, RTE_MAX_THREAD_NAME_LEN, "rte_mp_handle"); snprintf(thread_name, RTE_MAX_THREAD_NAME_LEN, "rte_mp_handle");
rte_thread_setname(tid, thread_name); rte_thread_setname(mp_handle_tid, thread_name);
/* try best to set thread name */
snprintf(thread_name, RTE_MAX_THREAD_NAME_LEN, "rte_mp_async_handle");
rte_thread_setname(async_reply_handle_tid, thread_name);
/* unlock the directory */ /* unlock the directory */
flock(dir_fd, LOCK_UN); flock(dir_fd, LOCK_UN);
@ -602,18 +826,77 @@ rte_mp_sendmsg(struct rte_mp_msg *msg)
} }
static int static int
mp_request_one(const char *dst, struct rte_mp_msg *req, mp_request_async(const char *dst, struct rte_mp_msg *req,
struct async_request_param *param)
{
struct rte_mp_msg *reply_msg;
struct pending_request *sync_req, *exist;
int ret;
sync_req = malloc(sizeof(*sync_req));
reply_msg = malloc(sizeof(*reply_msg));
if (sync_req == NULL || reply_msg == NULL) {
RTE_LOG(ERR, EAL, "Could not allocate space for sync request\n");
rte_errno = ENOMEM;
ret = -1;
goto fail;
}
memset(sync_req, 0, sizeof(*sync_req));
memset(reply_msg, 0, sizeof(*reply_msg));
sync_req->type = REQUEST_TYPE_ASYNC;
strcpy(sync_req->dst, dst);
sync_req->request = req;
sync_req->reply = reply_msg;
sync_req->async.param = param;
/* queue already locked by caller */
exist = find_sync_request(dst, req->name);
if (!exist) {
TAILQ_INSERT_TAIL(&pending_requests.requests, sync_req, next);
} else {
RTE_LOG(ERR, EAL, "A pending request %s:%s\n", dst, req->name);
rte_errno = EEXIST;
ret = -1;
goto fail;
}
ret = send_msg(dst, req, MP_REQ);
if (ret < 0) {
RTE_LOG(ERR, EAL, "Fail to send request %s:%s\n",
dst, req->name);
ret = -1;
goto fail;
} else if (ret == 0) {
ret = 0;
goto fail;
}
param->user_reply.nb_sent++;
return 0;
fail:
free(sync_req);
free(reply_msg);
return ret;
}
static int
mp_request_sync(const char *dst, struct rte_mp_msg *req,
struct rte_mp_reply *reply, const struct timespec *ts) struct rte_mp_reply *reply, const struct timespec *ts)
{ {
int ret; int ret;
struct rte_mp_msg msg, *tmp; struct rte_mp_msg msg, *tmp;
struct pending_request sync_req, *exist; struct pending_request sync_req, *exist;
sync_req.type = REQUEST_TYPE_SYNC;
sync_req.reply_received = 0; sync_req.reply_received = 0;
strcpy(sync_req.dst, dst); strcpy(sync_req.dst, dst);
sync_req.request = req; sync_req.request = req;
sync_req.reply = &msg; sync_req.reply = &msg;
pthread_cond_init(&sync_req.cond, NULL); pthread_cond_init(&sync_req.sync.cond, NULL);
pthread_mutex_lock(&pending_requests.lock); pthread_mutex_lock(&pending_requests.lock);
exist = find_sync_request(dst, req->name); exist = find_sync_request(dst, req->name);
@ -637,7 +920,7 @@ mp_request_one(const char *dst, struct rte_mp_msg *req,
reply->nb_sent++; reply->nb_sent++;
do { do {
ret = pthread_cond_timedwait(&sync_req.cond, ret = pthread_cond_timedwait(&sync_req.sync.cond,
&pending_requests.lock, ts); &pending_requests.lock, ts);
} while (ret != 0 && ret != ETIMEDOUT); } while (ret != 0 && ret != ETIMEDOUT);
@ -703,7 +986,7 @@ rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply,
/* for secondary process, send request to the primary process only */ /* for secondary process, send request to the primary process only */
if (rte_eal_process_type() == RTE_PROC_SECONDARY) if (rte_eal_process_type() == RTE_PROC_SECONDARY)
return mp_request_one(eal_mp_socket_path(), req, reply, &end); return mp_request_sync(eal_mp_socket_path(), req, reply, &end);
/* for primary process, broadcast request, and collect reply 1 by 1 */ /* for primary process, broadcast request, and collect reply 1 by 1 */
mp_dir = opendir(mp_dir_path); mp_dir = opendir(mp_dir_path);
@ -732,7 +1015,7 @@ rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply,
snprintf(path, sizeof(path), "%s/%s", mp_dir_path, snprintf(path, sizeof(path), "%s/%s", mp_dir_path,
ent->d_name); ent->d_name);
if (mp_request_one(path, req, reply, &end)) if (mp_request_sync(path, req, reply, &end))
ret = -1; ret = -1;
} }
/* unlock the directory */ /* unlock the directory */
@ -743,10 +1026,159 @@ rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply,
return ret; return ret;
} }
int __rte_experimental
rte_mp_request_async(struct rte_mp_msg *req, const struct timespec *ts,
rte_mp_async_reply_t clb)
{
struct rte_mp_msg *copy;
struct pending_request *dummy;
struct async_request_param *param;
struct rte_mp_reply *reply;
int dir_fd, ret = 0;
DIR *mp_dir;
struct dirent *ent;
struct timeval now;
struct timespec *end;
bool dummy_used = false;
RTE_LOG(DEBUG, EAL, "request: %s\n", req->name);
if (check_input(req) == false)
return -1;
if (gettimeofday(&now, NULL) < 0) {
RTE_LOG(ERR, EAL, "Faile to get current time\n");
rte_errno = errno;
return -1;
}
copy = malloc(sizeof(*copy));
dummy = malloc(sizeof(*dummy));
param = malloc(sizeof(*param));
if (copy == NULL || dummy == NULL || param == NULL) {
RTE_LOG(ERR, EAL, "Failed to allocate memory for async reply\n");
rte_errno = ENOMEM;
goto fail;
}
memset(copy, 0, sizeof(*copy));
memset(dummy, 0, sizeof(*dummy));
memset(param, 0, sizeof(*param));
/* copy message */
memcpy(copy, req, sizeof(*copy));
param->n_responses_processed = 0;
param->clb = clb;
end = &param->end;
reply = &param->user_reply;
end->tv_nsec = (now.tv_usec * 1000 + ts->tv_nsec) % 1000000000;
end->tv_sec = now.tv_sec + ts->tv_sec +
(now.tv_usec * 1000 + ts->tv_nsec) / 1000000000;
reply->nb_sent = 0;
reply->nb_received = 0;
reply->msgs = NULL;
/* we have to lock the request queue here, as we will be adding a bunch
* of requests to the queue at once, and some of the replies may arrive
* before we add all of the requests to the queue.
*/
pthread_mutex_lock(&pending_requests.lock);
/* we have to ensure that callback gets triggered even if we don't send
* anything, therefore earlier we have allocated a dummy request. fill
* it, and put it on the queue if we don't send any requests.
*/
dummy->type = REQUEST_TYPE_ASYNC;
dummy->request = copy;
dummy->reply = NULL;
dummy->async.param = param;
dummy->reply_received = 1; /* short-circuit the timeout */
/* for secondary process, send request to the primary process only */
if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
ret = mp_request_async(eal_mp_socket_path(), copy, param);
/* if we didn't send anything, put dummy request on the queue */
if (ret == 0 && reply->nb_sent == 0) {
TAILQ_INSERT_TAIL(&pending_requests.requests, dummy,
next);
dummy_used = true;
}
pthread_mutex_unlock(&pending_requests.lock);
/* if we couldn't send anything, clean up */
if (ret != 0)
goto fail;
return 0;
}
/* for primary process, broadcast request */
mp_dir = opendir(mp_dir_path);
if (!mp_dir) {
RTE_LOG(ERR, EAL, "Unable to open directory %s\n", mp_dir_path);
rte_errno = errno;
goto unlock_fail;
}
dir_fd = dirfd(mp_dir);
/* lock the directory to prevent processes spinning up while we send */
if (flock(dir_fd, LOCK_EX)) {
RTE_LOG(ERR, EAL, "Unable to lock directory %s\n",
mp_dir_path);
rte_errno = errno;
goto closedir_fail;
}
while ((ent = readdir(mp_dir))) {
char path[PATH_MAX];
if (fnmatch(mp_filter, ent->d_name, 0) != 0)
continue;
snprintf(path, sizeof(path), "%s/%s", mp_dir_path,
ent->d_name);
if (mp_request_async(path, copy, param))
ret = -1;
}
/* if we didn't send anything, put dummy request on the queue */
if (ret == 0 && reply->nb_sent == 0) {
TAILQ_INSERT_HEAD(&pending_requests.requests, dummy, next);
dummy_used = true;
}
/* trigger async request thread wake up */
pthread_cond_signal(&pending_requests.async_cond);
/* finally, unlock the queue */
pthread_mutex_unlock(&pending_requests.lock);
/* unlock the directory */
flock(dir_fd, LOCK_UN);
/* dir_fd automatically closed on closedir */
closedir(mp_dir);
/* if dummy was unused, free it */
if (!dummy_used)
free(dummy);
return ret;
closedir_fail:
closedir(mp_dir);
unlock_fail:
pthread_mutex_unlock(&pending_requests.lock);
fail:
free(dummy);
free(param);
free(copy);
return -1;
}
int __rte_experimental int __rte_experimental
rte_mp_reply(struct rte_mp_msg *msg, const char *peer) rte_mp_reply(struct rte_mp_msg *msg, const char *peer)
{ {
RTE_LOG(DEBUG, EAL, "reply: %s\n", msg->name); RTE_LOG(DEBUG, EAL, "reply: %s\n", msg->name);
if (check_input(msg) == false) if (check_input(msg) == false)

View File

@ -229,6 +229,16 @@ struct rte_mp_reply {
*/ */
typedef int (*rte_mp_t)(const struct rte_mp_msg *msg, const void *peer); typedef int (*rte_mp_t)(const struct rte_mp_msg *msg, const void *peer);
/**
* Asynchronous reply function typedef used by other components.
*
* As we create socket channel for primary/secondary communication, use
* this function typedef to register action for coming responses to asynchronous
* requests.
*/
typedef int (*rte_mp_async_reply_t)(const struct rte_mp_msg *request,
const struct rte_mp_reply *reply);
/** /**
* @warning * @warning
* @b EXPERIMENTAL: this API may change without prior notice * @b EXPERIMENTAL: this API may change without prior notice
@ -317,6 +327,32 @@ int __rte_experimental
rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply, rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply,
const struct timespec *ts); const struct timespec *ts);
/**
* @warning
* @b EXPERIMENTAL: this API may change without prior notice
*
* Send a request to the peer process and expect a reply in a separate callback.
*
* This function sends a request message to the peer process, and will not
* block. Instead, reply will be received in a separate callback.
*
* @param req
* The req argument contains the customized request message.
*
* @param ts
* The ts argument specifies how long we can wait for the peer(s) to reply.
*
* @param clb
* The callback to trigger when all responses for this request have arrived.
*
* @return
* - On success, return 0.
* - On failure, return -1, and the reason will be stored in rte_errno.
*/
int __rte_experimental
rte_mp_request_async(struct rte_mp_msg *req, const struct timespec *ts,
rte_mp_async_reply_t clb);
/** /**
* @warning * @warning
* @b EXPERIMENTAL: this API may change without prior notice * @b EXPERIMENTAL: this API may change without prior notice

View File

@ -226,6 +226,7 @@ EXPERIMENTAL {
rte_mp_action_unregister; rte_mp_action_unregister;
rte_mp_reply; rte_mp_reply;
rte_mp_request_sync; rte_mp_request_sync;
rte_mp_request_async;
rte_mp_sendmsg; rte_mp_sendmsg;
rte_service_attr_get; rte_service_attr_get;
rte_service_attr_reset_all; rte_service_attr_reset_all;