Seth Howell e71e81b631 sock: keep track of removed sockets during call to poll
We have been intermittently hitting the assert where
we check sock->cb_fn != NULL in spdk_sock_group_impl_poll_count.

The only way we could be hitting this specific error is if we
wereremoving a socket from a sock group within after receiving
an event for it.

Specifically, we are seeing this error on the NVMe-oF TCP target
which relies on posix sockets using epoll.

The man page for epoll states the following:

 If you use an event cache or store all the file descriptors
 returned from epoll_wait(2), then make sure to provide
 a  way  to  mark its closure dynamically (i.e., caused by
 a previous event's processing).  Suppose you receive 100 events
 from epoll_wait(2), and in event #47 a condition causes event
 #13 to be closed.  If you remove  the  structure  and close(2)
 the file descriptor for event #13, then your event cache might
 still say there are events waiting for that file descriptor
 causing confusion.

 One solution for this is to call, during the processing
 of  event  47,  epoll_ctl(EPOLL_CTL_DEL)  to  delete  file
 descriptor  13 and close(2), then mark its associated data
 structure as removed and link it to a cleanup list.  If
 you find another event for file descriptor 13 in your batch
 processing, you will discover the file descriptor  had
 been previously removed and there will be no confusion.

Since we do store all of the file descriptors returned from
epoll_wait, we need to implement the tracking mentioned above.

fixes issue #1294

Signed-off-by: Seth Howell <seth.howell@intel.com>
Change-Id: Ib592ce19e3f0b691e3a825d02ebb42d7338e3ceb
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/1589
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Aleksey Marchuk <alexeymar@mellanox.com>
2020-04-06 07:48:33 +00:00

647 lines
14 KiB
C

/*-
* BSD LICENSE
*
* Copyright (c) Intel Corporation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "spdk/stdinc.h"
#include "spdk/log.h"
#include "spdk/sock.h"
#include "spdk_internal/sock.h"
#include "spdk/queue.h"
static STAILQ_HEAD(, spdk_net_impl) g_net_impls = STAILQ_HEAD_INITIALIZER(g_net_impls);
struct spdk_sock_placement_id_entry {
int placement_id;
uint32_t ref;
struct spdk_sock_group *group;
STAILQ_ENTRY(spdk_sock_placement_id_entry) link;
};
static STAILQ_HEAD(, spdk_sock_placement_id_entry) g_placement_id_map = STAILQ_HEAD_INITIALIZER(
g_placement_id_map);
static pthread_mutex_t g_map_table_mutex = PTHREAD_MUTEX_INITIALIZER;
/* Insert a group into the placement map.
* If the group is already in the map, take a reference.
*/
static int
spdk_sock_map_insert(int placement_id, struct spdk_sock_group *group)
{
struct spdk_sock_placement_id_entry *entry;
pthread_mutex_lock(&g_map_table_mutex);
STAILQ_FOREACH(entry, &g_placement_id_map, link) {
if (placement_id == entry->placement_id) {
/* The mapping already exists, it means that different sockets have
* the same placement_ids.
*/
entry->ref++;
pthread_mutex_unlock(&g_map_table_mutex);
return 0;
}
}
entry = calloc(1, sizeof(*entry));
if (!entry) {
SPDK_ERRLOG("Cannot allocate an entry for placement_id=%u\n", placement_id);
pthread_mutex_unlock(&g_map_table_mutex);
return -ENOMEM;
}
entry->placement_id = placement_id;
entry->group = group;
entry->ref++;
STAILQ_INSERT_TAIL(&g_placement_id_map, entry, link);
pthread_mutex_unlock(&g_map_table_mutex);
return 0;
}
/* Release a reference to the group for a given placement_id.
* If the reference count is 0, remove the group.
*/
static void
spdk_sock_map_release(int placement_id)
{
struct spdk_sock_placement_id_entry *entry;
pthread_mutex_lock(&g_map_table_mutex);
STAILQ_FOREACH(entry, &g_placement_id_map, link) {
if (placement_id == entry->placement_id) {
assert(entry->ref > 0);
entry->ref--;
if (!entry->ref) {
STAILQ_REMOVE(&g_placement_id_map, entry, spdk_sock_placement_id_entry, link);
free(entry);
}
break;
}
}
pthread_mutex_unlock(&g_map_table_mutex);
}
/* Look up the group for a placement_id. */
static void
spdk_sock_map_lookup(int placement_id, struct spdk_sock_group **group)
{
struct spdk_sock_placement_id_entry *entry;
*group = NULL;
pthread_mutex_lock(&g_map_table_mutex);
STAILQ_FOREACH(entry, &g_placement_id_map, link) {
if (placement_id == entry->placement_id) {
assert(entry->group != NULL);
*group = entry->group;
break;
}
}
pthread_mutex_unlock(&g_map_table_mutex);
}
/* Remove the socket group from the map table */
static void
spdk_sock_remove_sock_group_from_map_table(struct spdk_sock_group *group)
{
struct spdk_sock_placement_id_entry *entry, *tmp;
pthread_mutex_lock(&g_map_table_mutex);
STAILQ_FOREACH_SAFE(entry, &g_placement_id_map, link, tmp) {
if (entry->group == group) {
STAILQ_REMOVE(&g_placement_id_map, entry, spdk_sock_placement_id_entry, link);
free(entry);
}
}
pthread_mutex_unlock(&g_map_table_mutex);
}
int
spdk_sock_get_optimal_sock_group(struct spdk_sock *sock, struct spdk_sock_group **group)
{
int placement_id = 0, rc;
rc = sock->net_impl->get_placement_id(sock, &placement_id);
if (!rc && (placement_id != 0)) {
spdk_sock_map_lookup(placement_id, group);
return 0;
} else {
return -1;
}
}
int
spdk_sock_getaddr(struct spdk_sock *sock, char *saddr, int slen, uint16_t *sport,
char *caddr, int clen, uint16_t *cport)
{
return sock->net_impl->getaddr(sock, saddr, slen, sport, caddr, clen, cport);
}
struct spdk_sock *
spdk_sock_connect(const char *ip, int port, char *impl_name)
{
struct spdk_net_impl *impl = NULL;
struct spdk_sock *sock;
STAILQ_FOREACH_FROM(impl, &g_net_impls, link) {
if (impl_name && strncmp(impl_name, impl->name, strlen(impl->name) + 1)) {
continue;
}
sock = impl->connect(ip, port);
if (sock != NULL) {
sock->net_impl = impl;
TAILQ_INIT(&sock->queued_reqs);
TAILQ_INIT(&sock->pending_reqs);
return sock;
}
}
return NULL;
}
struct spdk_sock *
spdk_sock_listen(const char *ip, int port, char *impl_name)
{
struct spdk_net_impl *impl = NULL;
struct spdk_sock *sock;
STAILQ_FOREACH_FROM(impl, &g_net_impls, link) {
if (impl_name && strncmp(impl_name, impl->name, strlen(impl->name) + 1)) {
continue;
}
sock = impl->listen(ip, port);
if (sock != NULL) {
sock->net_impl = impl;
/* Don't need to initialize the request queues for listen
* sockets. */
return sock;
}
}
return NULL;
}
struct spdk_sock *
spdk_sock_accept(struct spdk_sock *sock)
{
struct spdk_sock *new_sock;
new_sock = sock->net_impl->accept(sock);
if (new_sock != NULL) {
new_sock->net_impl = sock->net_impl;
TAILQ_INIT(&new_sock->queued_reqs);
TAILQ_INIT(&new_sock->pending_reqs);
}
return new_sock;
}
int
spdk_sock_close(struct spdk_sock **_sock)
{
struct spdk_sock *sock = *_sock;
int rc;
if (sock == NULL) {
errno = EBADF;
return -1;
}
if (sock->cb_fn != NULL) {
/* This sock is still part of a sock_group. */
errno = EBUSY;
return -1;
}
sock->flags.closed = true;
if (sock->cb_cnt > 0) {
/* Let the callback unwind before destroying the socket */
return 0;
}
spdk_sock_abort_requests(sock);
rc = sock->net_impl->close(sock);
if (rc == 0) {
*_sock = NULL;
}
return rc;
}
ssize_t
spdk_sock_recv(struct spdk_sock *sock, void *buf, size_t len)
{
if (sock == NULL) {
errno = EBADF;
return -1;
}
if (sock->flags.closed) {
errno = EBADF;
return -1;
}
return sock->net_impl->recv(sock, buf, len);
}
ssize_t
spdk_sock_readv(struct spdk_sock *sock, struct iovec *iov, int iovcnt)
{
if (sock == NULL) {
errno = EBADF;
return -1;
}
if (sock->flags.closed) {
errno = EBADF;
return -1;
}
return sock->net_impl->readv(sock, iov, iovcnt);
}
ssize_t
spdk_sock_writev(struct spdk_sock *sock, struct iovec *iov, int iovcnt)
{
if (sock == NULL) {
errno = EBADF;
return -1;
}
if (sock->flags.closed) {
errno = EBADF;
return -1;
}
return sock->net_impl->writev(sock, iov, iovcnt);
}
void
spdk_sock_writev_async(struct spdk_sock *sock, struct spdk_sock_request *req)
{
assert(req->cb_fn != NULL);
if (sock == NULL) {
req->cb_fn(req->cb_arg, -EBADF);
return;
}
if (sock->flags.closed) {
req->cb_fn(req->cb_arg, -EBADF);
return;
}
sock->net_impl->writev_async(sock, req);
}
int
spdk_sock_flush(struct spdk_sock *sock)
{
if (sock == NULL) {
return -EBADF;
}
if (sock->flags.closed) {
return -EBADF;
}
return sock->net_impl->flush(sock);
}
int
spdk_sock_set_recvlowat(struct spdk_sock *sock, int nbytes)
{
return sock->net_impl->set_recvlowat(sock, nbytes);
}
int
spdk_sock_set_recvbuf(struct spdk_sock *sock, int sz)
{
return sock->net_impl->set_recvbuf(sock, sz);
}
int
spdk_sock_set_sendbuf(struct spdk_sock *sock, int sz)
{
return sock->net_impl->set_sendbuf(sock, sz);
}
int
spdk_sock_set_priority(struct spdk_sock *sock, int priority)
{
return sock->net_impl->set_priority(sock, priority);
}
bool
spdk_sock_is_ipv6(struct spdk_sock *sock)
{
return sock->net_impl->is_ipv6(sock);
}
bool
spdk_sock_is_ipv4(struct spdk_sock *sock)
{
return sock->net_impl->is_ipv4(sock);
}
bool
spdk_sock_is_connected(struct spdk_sock *sock)
{
return sock->net_impl->is_connected(sock);
}
struct spdk_sock_group *
spdk_sock_group_create(void *ctx)
{
struct spdk_net_impl *impl = NULL;
struct spdk_sock_group *group;
struct spdk_sock_group_impl *group_impl;
group = calloc(1, sizeof(*group));
if (group == NULL) {
return NULL;
}
STAILQ_INIT(&group->group_impls);
STAILQ_FOREACH_FROM(impl, &g_net_impls, link) {
group_impl = impl->group_impl_create();
if (group_impl != NULL) {
STAILQ_INSERT_TAIL(&group->group_impls, group_impl, link);
TAILQ_INIT(&group_impl->socks);
group_impl->num_removed_socks = 0;
group_impl->net_impl = impl;
}
}
group->ctx = ctx;
return group;
}
void *
spdk_sock_group_get_ctx(struct spdk_sock_group *group)
{
if (group == NULL) {
return NULL;
}
return group->ctx;
}
int
spdk_sock_group_add_sock(struct spdk_sock_group *group, struct spdk_sock *sock,
spdk_sock_cb cb_fn, void *cb_arg)
{
struct spdk_sock_group_impl *group_impl = NULL;
int rc, placement_id = 0;
if (cb_fn == NULL) {
errno = EINVAL;
return -1;
}
if (sock->group_impl != NULL) {
/*
* This sock is already part of a sock_group. Currently we don't
* support this.
*/
errno = EBUSY;
return -1;
}
rc = sock->net_impl->get_placement_id(sock, &placement_id);
if (!rc && (placement_id != 0)) {
rc = spdk_sock_map_insert(placement_id, group);
if (rc < 0) {
return -1;
}
}
STAILQ_FOREACH_FROM(group_impl, &group->group_impls, link) {
if (sock->net_impl == group_impl->net_impl) {
break;
}
}
if (group_impl == NULL) {
errno = EINVAL;
return -1;
}
rc = group_impl->net_impl->group_impl_add_sock(group_impl, sock);
if (rc == 0) {
TAILQ_INSERT_TAIL(&group_impl->socks, sock, link);
sock->group_impl = group_impl;
sock->cb_fn = cb_fn;
sock->cb_arg = cb_arg;
}
return rc;
}
int
spdk_sock_group_remove_sock(struct spdk_sock_group *group, struct spdk_sock *sock)
{
struct spdk_sock_group_impl *group_impl = NULL;
int rc, placement_id = 0;
STAILQ_FOREACH_FROM(group_impl, &group->group_impls, link) {
if (sock->net_impl == group_impl->net_impl) {
break;
}
}
if (group_impl == NULL) {
errno = EINVAL;
return -1;
}
assert(group_impl == sock->group_impl);
rc = sock->net_impl->get_placement_id(sock, &placement_id);
if (!rc && (placement_id != 0)) {
spdk_sock_map_release(placement_id);
}
rc = group_impl->net_impl->group_impl_remove_sock(group_impl, sock);
if (rc == 0) {
TAILQ_REMOVE(&group_impl->socks, sock, link);
assert(group_impl->num_removed_socks < MAX_EVENTS_PER_POLL);
group_impl->removed_socks[group_impl->num_removed_socks] = (uintptr_t)sock;
group_impl->num_removed_socks++;
sock->group_impl = NULL;
sock->cb_fn = NULL;
sock->cb_arg = NULL;
}
return rc;
}
int
spdk_sock_group_poll(struct spdk_sock_group *group)
{
return spdk_sock_group_poll_count(group, MAX_EVENTS_PER_POLL);
}
static int
spdk_sock_group_impl_poll_count(struct spdk_sock_group_impl *group_impl,
struct spdk_sock_group *group,
int max_events)
{
struct spdk_sock *socks[MAX_EVENTS_PER_POLL];
int num_events, i;
if (TAILQ_EMPTY(&group_impl->socks)) {
return 0;
}
/* The number of removed sockets should be reset for each call to poll. */
group_impl->num_removed_socks = 0;
num_events = group_impl->net_impl->group_impl_poll(group_impl, max_events, socks);
if (num_events == -1) {
return -1;
}
for (i = 0; i < num_events; i++) {
struct spdk_sock *sock = socks[i];
int j;
bool valid = true;
for (j = 0; j < group_impl->num_removed_socks; j++) {
if ((uintptr_t)sock == group_impl->removed_socks[j]) {
valid = false;
break;
}
}
if (valid) {
assert(sock->cb_fn != NULL);
sock->cb_fn(sock->cb_arg, group, sock);
}
}
return num_events;
}
int
spdk_sock_group_poll_count(struct spdk_sock_group *group, int max_events)
{
struct spdk_sock_group_impl *group_impl = NULL;
int rc, num_events = 0;
if (max_events < 1) {
errno = -EINVAL;
return -1;
}
/*
* Only poll for up to 32 events at a time - if more events are pending,
* the next call to this function will reap them.
*/
if (max_events > MAX_EVENTS_PER_POLL) {
max_events = MAX_EVENTS_PER_POLL;
}
STAILQ_FOREACH_FROM(group_impl, &group->group_impls, link) {
rc = spdk_sock_group_impl_poll_count(group_impl, group, max_events);
if (rc < 0) {
num_events = -1;
SPDK_ERRLOG("group_impl_poll_count for net(%s) failed\n",
group_impl->net_impl->name);
} else if (num_events >= 0) {
num_events += rc;
}
}
return num_events;
}
int
spdk_sock_group_close(struct spdk_sock_group **group)
{
struct spdk_sock_group_impl *group_impl = NULL, *tmp;
int rc;
if (*group == NULL) {
errno = EBADF;
return -1;
}
STAILQ_FOREACH_SAFE(group_impl, &(*group)->group_impls, link, tmp) {
if (!TAILQ_EMPTY(&group_impl->socks)) {
errno = EBUSY;
return -1;
}
}
STAILQ_FOREACH_SAFE(group_impl, &(*group)->group_impls, link, tmp) {
rc = group_impl->net_impl->group_impl_close(group_impl);
if (rc != 0) {
SPDK_ERRLOG("group_impl_close for net(%s) failed\n",
group_impl->net_impl->name);
}
}
spdk_sock_remove_sock_group_from_map_table(*group);
free(*group);
*group = NULL;
return 0;
}
void
spdk_net_impl_register(struct spdk_net_impl *impl, int priority)
{
struct spdk_net_impl *cur, *prev;
impl->priority = priority;
prev = NULL;
STAILQ_FOREACH(cur, &g_net_impls, link) {
if (impl->priority > cur->priority) {
break;
}
prev = cur;
}
if (prev) {
STAILQ_INSERT_AFTER(&g_net_impls, prev, impl, link);
} else {
STAILQ_INSERT_HEAD(&g_net_impls, impl, link);
}
}