diff options
Diffstat (limited to 'src/core/lib/iomgr/ev_poll_posix.c')
| -rw-r--r-- | src/core/lib/iomgr/ev_poll_posix.c | 1267 |
1 files changed, 1267 insertions, 0 deletions
diff --git a/src/core/lib/iomgr/ev_poll_posix.c b/src/core/lib/iomgr/ev_poll_posix.c new file mode 100644 index 0000000000..45c0a5e954 --- /dev/null +++ b/src/core/lib/iomgr/ev_poll_posix.c @@ -0,0 +1,1267 @@ +/* + * + * Copyright 2016, Google Inc. + * 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 Google Inc. 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 <grpc/support/port_platform.h> + +#ifdef GPR_POSIX_SOCKET + +#include "src/core/lib/iomgr/ev_poll_posix.h" + +#include <assert.h> +#include <errno.h> +#include <poll.h> +#include <string.h> +#include <sys/socket.h> +#include <unistd.h> + +#include <grpc/support/alloc.h> +#include <grpc/support/log.h> +#include <grpc/support/string_util.h> +#include <grpc/support/tls.h> +#include <grpc/support/useful.h> + +#include "src/core/lib/iomgr/iomgr_internal.h" +#include "src/core/lib/iomgr/wakeup_fd_posix.h" +#include "src/core/lib/profiling/timers.h" +#include "src/core/lib/support/block_annotate.h" + +/******************************************************************************* + * FD declarations + */ + +typedef struct grpc_fd_watcher { + struct grpc_fd_watcher *next; + struct grpc_fd_watcher *prev; + grpc_pollset *pollset; + grpc_pollset_worker *worker; + grpc_fd *fd; +} grpc_fd_watcher; + +struct grpc_fd { + int fd; + /* refst format: + bit0: 1=active/0=orphaned + bit1-n: refcount + meaning that mostly we ref by two to avoid altering the orphaned bit, + and just unref by 1 when we're ready to flag the object as orphaned */ + gpr_atm refst; + + gpr_mu mu; + int shutdown; + int closed; + int released; + + /* The watcher list. + + The following watcher related fields are protected by watcher_mu. + + An fd_watcher is an ephemeral object created when an fd wants to + begin polling, and destroyed after the poll. + + It denotes the fd's interest in whether to read poll or write poll + or both or neither on this fd. + + If a watcher is asked to poll for reads or writes, the read_watcher + or write_watcher fields are set respectively. A watcher may be asked + to poll for both, in which case both fields will be set. + + read_watcher and write_watcher may be NULL if no watcher has been + asked to poll for reads or writes. + + If an fd_watcher is not asked to poll for reads or writes, it's added + to a linked list of inactive watchers, rooted at inactive_watcher_root. + If at a later time there becomes need of a poller to poll, one of + the inactive pollers may be kicked out of their poll loops to take + that responsibility. */ + grpc_fd_watcher inactive_watcher_root; + grpc_fd_watcher *read_watcher; + grpc_fd_watcher *write_watcher; + + grpc_closure *read_closure; + grpc_closure *write_closure; + + grpc_closure *on_done_closure; + + grpc_iomgr_object iomgr_object; + + /* The pollset that last noticed and notified that the fd is readable */ + grpc_pollset *read_notifier_pollset; +}; + +/* Begin polling on an fd. + Registers that the given pollset is interested in this fd - so that if read + or writability interest changes, the pollset can be kicked to pick up that + new interest. + Return value is: + (fd_needs_read? read_mask : 0) | (fd_needs_write? write_mask : 0) + i.e. a combination of read_mask and write_mask determined by the fd's current + interest in said events. + Polling strategies that do not need to alter their behavior depending on the + fd's current interest (such as epoll) do not need to call this function. + MUST NOT be called with a pollset lock taken */ +static uint32_t fd_begin_poll(grpc_fd *fd, grpc_pollset *pollset, + grpc_pollset_worker *worker, uint32_t read_mask, + uint32_t write_mask, grpc_fd_watcher *rec); +/* Complete polling previously started with fd_begin_poll + MUST NOT be called with a pollset lock taken + if got_read or got_write are 1, also does the become_{readable,writable} as + appropriate. */ +static void fd_end_poll(grpc_exec_ctx *exec_ctx, grpc_fd_watcher *rec, + int got_read, int got_write, + grpc_pollset *read_notifier_pollset); + +/* Return 1 if this fd is orphaned, 0 otherwise */ +static bool fd_is_orphaned(grpc_fd *fd); + +/* Reference counting for fds */ +/*#define GRPC_FD_REF_COUNT_DEBUG*/ +#ifdef GRPC_FD_REF_COUNT_DEBUG +static void fd_ref(grpc_fd *fd, const char *reason, const char *file, int line); +static void fd_unref(grpc_fd *fd, const char *reason, const char *file, + int line); +#define GRPC_FD_REF(fd, reason) fd_ref(fd, reason, __FILE__, __LINE__) +#define GRPC_FD_UNREF(fd, reason) fd_unref(fd, reason, __FILE__, __LINE__) +#else +static void fd_ref(grpc_fd *fd); +static void fd_unref(grpc_fd *fd); +#define GRPC_FD_REF(fd, reason) fd_ref(fd) +#define GRPC_FD_UNREF(fd, reason) fd_unref(fd) +#endif + +#define CLOSURE_NOT_READY ((grpc_closure *)0) +#define CLOSURE_READY ((grpc_closure *)1) + +/******************************************************************************* + * pollset declarations + */ + +typedef struct grpc_cached_wakeup_fd { + grpc_wakeup_fd fd; + struct grpc_cached_wakeup_fd *next; +} grpc_cached_wakeup_fd; + +struct grpc_pollset_worker { + grpc_cached_wakeup_fd *wakeup_fd; + int reevaluate_polling_on_wakeup; + int kicked_specifically; + struct grpc_pollset_worker *next; + struct grpc_pollset_worker *prev; +}; + +struct grpc_pollset { + gpr_mu mu; + grpc_pollset_worker root_worker; + int shutting_down; + int called_shutdown; + int kicked_without_pollers; + grpc_closure *shutdown_done; + grpc_closure_list idle_jobs; + /* all polled fds */ + size_t fd_count; + size_t fd_capacity; + grpc_fd **fds; + /* Local cache of eventfds for workers */ + grpc_cached_wakeup_fd *local_wakeup_cache; +}; + +/* Add an fd to a pollset */ +static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + struct grpc_fd *fd); + +static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *pollset_set, grpc_fd *fd); + +/* Convert a timespec to milliseconds: + - very small or negative poll times are clamped to zero to do a + non-blocking poll (which becomes spin polling) + - other small values are rounded up to one millisecond + - longer than a millisecond polls are rounded up to the next nearest + millisecond to avoid spinning + - infinite timeouts are converted to -1 */ +static int poll_deadline_to_millis_timeout(gpr_timespec deadline, + gpr_timespec now); + +/* Allow kick to wakeup the currently polling worker */ +#define GRPC_POLLSET_CAN_KICK_SELF 1 +/* Force the wakee to repoll when awoken */ +#define GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP 2 +/* As per pollset_kick, with an extended set of flags (defined above) + -- mostly for fd_posix's use. */ +static grpc_error *pollset_kick_ext(grpc_pollset *p, + grpc_pollset_worker *specific_worker, + uint32_t flags) GRPC_MUST_USE_RESULT; + +/* Return 1 if the pollset has active threads in pollset_work (pollset must + * be locked) */ +static int pollset_has_workers(grpc_pollset *pollset); + +/******************************************************************************* + * pollset_set definitions + */ + +struct grpc_pollset_set { + gpr_mu mu; + + size_t pollset_count; + size_t pollset_capacity; + grpc_pollset **pollsets; + + size_t pollset_set_count; + size_t pollset_set_capacity; + struct grpc_pollset_set **pollset_sets; + + size_t fd_count; + size_t fd_capacity; + grpc_fd **fds; +}; + +/******************************************************************************* + * fd_posix.c + */ + +#ifdef GRPC_FD_REF_COUNT_DEBUG +#define REF_BY(fd, n, reason) ref_by(fd, n, reason, __FILE__, __LINE__) +#define UNREF_BY(fd, n, reason) unref_by(fd, n, reason, __FILE__, __LINE__) +static void ref_by(grpc_fd *fd, int n, const char *reason, const char *file, + int line) { + gpr_log(GPR_DEBUG, "FD %d %p ref %d %d -> %d [%s; %s:%d]", fd->fd, fd, n, + gpr_atm_no_barrier_load(&fd->refst), + gpr_atm_no_barrier_load(&fd->refst) + n, reason, file, line); +#else +#define REF_BY(fd, n, reason) ref_by(fd, n) +#define UNREF_BY(fd, n, reason) unref_by(fd, n) +static void ref_by(grpc_fd *fd, int n) { +#endif + GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&fd->refst, n) > 0); +} + +#ifdef GRPC_FD_REF_COUNT_DEBUG +static void unref_by(grpc_fd *fd, int n, const char *reason, const char *file, + int line) { + gpr_atm old; + gpr_log(GPR_DEBUG, "FD %d %p unref %d %d -> %d [%s; %s:%d]", fd->fd, fd, n, + gpr_atm_no_barrier_load(&fd->refst), + gpr_atm_no_barrier_load(&fd->refst) - n, reason, file, line); +#else +static void unref_by(grpc_fd *fd, int n) { + gpr_atm old; +#endif + old = gpr_atm_full_fetch_add(&fd->refst, -n); + if (old == n) { + gpr_mu_destroy(&fd->mu); + grpc_iomgr_unregister_object(&fd->iomgr_object); + gpr_free(fd); + } else { + GPR_ASSERT(old > n); + } +} + +static grpc_fd *fd_create(int fd, const char *name) { + grpc_fd *r = gpr_malloc(sizeof(*r)); + gpr_mu_init(&r->mu); + gpr_atm_rel_store(&r->refst, 1); + r->shutdown = 0; + r->read_closure = CLOSURE_NOT_READY; + r->write_closure = CLOSURE_NOT_READY; + r->fd = fd; + r->inactive_watcher_root.next = r->inactive_watcher_root.prev = + &r->inactive_watcher_root; + r->read_watcher = r->write_watcher = NULL; + r->on_done_closure = NULL; + r->closed = 0; + r->released = 0; + r->read_notifier_pollset = NULL; + + char *name2; + gpr_asprintf(&name2, "%s fd=%d", name, fd); + grpc_iomgr_register_object(&r->iomgr_object, name2); + gpr_free(name2); +#ifdef GRPC_FD_REF_COUNT_DEBUG + gpr_log(GPR_DEBUG, "FD %d %p create %s", fd, r, name); +#endif + return r; +} + +static bool fd_is_orphaned(grpc_fd *fd) { + return (gpr_atm_acq_load(&fd->refst) & 1) == 0; +} + +/* Return the read-notifier pollset */ +static grpc_pollset *fd_get_read_notifier_pollset(grpc_exec_ctx *exec_ctx, + grpc_fd *fd) { + grpc_pollset *notifier = NULL; + + gpr_mu_lock(&fd->mu); + notifier = fd->read_notifier_pollset; + gpr_mu_unlock(&fd->mu); + + return notifier; +} + +static grpc_error *pollset_kick_locked(grpc_fd_watcher *watcher) { + gpr_mu_lock(&watcher->pollset->mu); + GPR_ASSERT(watcher->worker); + grpc_error *err = pollset_kick_ext(watcher->pollset, watcher->worker, + GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP); + gpr_mu_unlock(&watcher->pollset->mu); + return err; +} + +static void maybe_wake_one_watcher_locked(grpc_fd *fd) { + if (fd->inactive_watcher_root.next != &fd->inactive_watcher_root) { + pollset_kick_locked(fd->inactive_watcher_root.next); + } else if (fd->read_watcher) { + pollset_kick_locked(fd->read_watcher); + } else if (fd->write_watcher) { + pollset_kick_locked(fd->write_watcher); + } +} + +static void wake_all_watchers_locked(grpc_fd *fd) { + grpc_fd_watcher *watcher; + for (watcher = fd->inactive_watcher_root.next; + watcher != &fd->inactive_watcher_root; watcher = watcher->next) { + pollset_kick_locked(watcher); + } + if (fd->read_watcher) { + pollset_kick_locked(fd->read_watcher); + } + if (fd->write_watcher && fd->write_watcher != fd->read_watcher) { + pollset_kick_locked(fd->write_watcher); + } +} + +static int has_watchers(grpc_fd *fd) { + return fd->read_watcher != NULL || fd->write_watcher != NULL || + fd->inactive_watcher_root.next != &fd->inactive_watcher_root; +} + +static void close_fd_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd) { + fd->closed = 1; + if (!fd->released) { + close(fd->fd); + } + grpc_exec_ctx_sched(exec_ctx, fd->on_done_closure, GRPC_ERROR_NONE, NULL); +} + +static int fd_wrapped_fd(grpc_fd *fd) { + if (fd->released || fd->closed) { + return -1; + } else { + return fd->fd; + } +} + +static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd, + grpc_closure *on_done, int *release_fd, + const char *reason) { + fd->on_done_closure = on_done; + fd->released = release_fd != NULL; + if (!fd->released) { + shutdown(fd->fd, SHUT_RDWR); + } else { + *release_fd = fd->fd; + } + gpr_mu_lock(&fd->mu); + REF_BY(fd, 1, reason); /* remove active status, but keep referenced */ + if (!has_watchers(fd)) { + close_fd_locked(exec_ctx, fd); + } else { + wake_all_watchers_locked(fd); + } + gpr_mu_unlock(&fd->mu); + UNREF_BY(fd, 2, reason); /* drop the reference */ +} + +/* increment refcount by two to avoid changing the orphan bit */ +#ifdef GRPC_FD_REF_COUNT_DEBUG +static void fd_ref(grpc_fd *fd, const char *reason, const char *file, + int line) { + ref_by(fd, 2, reason, file, line); +} + +static void fd_unref(grpc_fd *fd, const char *reason, const char *file, + int line) { + unref_by(fd, 2, reason, file, line); +} +#else +static void fd_ref(grpc_fd *fd) { ref_by(fd, 2); } + +static void fd_unref(grpc_fd *fd) { unref_by(fd, 2); } +#endif + +static grpc_error *fd_shutdown_error(bool shutdown) { + if (!shutdown) { + return GRPC_ERROR_NONE; + } else { + return GRPC_ERROR_CREATE("FD shutdown"); + } +} + +static void notify_on_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd, + grpc_closure **st, grpc_closure *closure) { + if (fd->shutdown) { + grpc_exec_ctx_sched(exec_ctx, closure, GRPC_ERROR_CREATE("FD shutdown"), + NULL); + } else if (*st == CLOSURE_NOT_READY) { + /* not ready ==> switch to a waiting state by setting the closure */ + *st = closure; + } else if (*st == CLOSURE_READY) { + /* already ready ==> queue the closure to run immediately */ + *st = CLOSURE_NOT_READY; + grpc_exec_ctx_sched(exec_ctx, closure, fd_shutdown_error(fd->shutdown), + NULL); + maybe_wake_one_watcher_locked(fd); + } else { + /* upcallptr was set to a different closure. This is an error! */ + gpr_log(GPR_ERROR, + "User called a notify_on function with a previous callback still " + "pending"); + abort(); + } +} + +/* returns 1 if state becomes not ready */ +static int set_ready_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd, + grpc_closure **st) { + if (*st == CLOSURE_READY) { + /* duplicate ready ==> ignore */ + return 0; + } else if (*st == CLOSURE_NOT_READY) { + /* not ready, and not waiting ==> flag ready */ + *st = CLOSURE_READY; + return 0; + } else { + /* waiting ==> queue closure */ + grpc_exec_ctx_sched(exec_ctx, *st, fd_shutdown_error(fd->shutdown), NULL); + *st = CLOSURE_NOT_READY; + return 1; + } +} + +static void set_read_notifier_pollset_locked( + grpc_exec_ctx *exec_ctx, grpc_fd *fd, grpc_pollset *read_notifier_pollset) { + fd->read_notifier_pollset = read_notifier_pollset; +} + +static void fd_shutdown(grpc_exec_ctx *exec_ctx, grpc_fd *fd) { + gpr_mu_lock(&fd->mu); + /* only shutdown once */ + if (!fd->shutdown) { + fd->shutdown = 1; + /* signal read/write closed to OS so that future operations fail */ + shutdown(fd->fd, SHUT_RDWR); + set_ready_locked(exec_ctx, fd, &fd->read_closure); + set_ready_locked(exec_ctx, fd, &fd->write_closure); + } + gpr_mu_unlock(&fd->mu); +} + +static bool fd_is_shutdown(grpc_fd *fd) { + gpr_mu_lock(&fd->mu); + bool r = fd->shutdown; + gpr_mu_unlock(&fd->mu); + return r; +} + +static void fd_notify_on_read(grpc_exec_ctx *exec_ctx, grpc_fd *fd, + grpc_closure *closure) { + gpr_mu_lock(&fd->mu); + notify_on_locked(exec_ctx, fd, &fd->read_closure, closure); + gpr_mu_unlock(&fd->mu); +} + +static void fd_notify_on_write(grpc_exec_ctx *exec_ctx, grpc_fd *fd, + grpc_closure *closure) { + gpr_mu_lock(&fd->mu); + notify_on_locked(exec_ctx, fd, &fd->write_closure, closure); + gpr_mu_unlock(&fd->mu); +} + +static uint32_t fd_begin_poll(grpc_fd *fd, grpc_pollset *pollset, + grpc_pollset_worker *worker, uint32_t read_mask, + uint32_t write_mask, grpc_fd_watcher *watcher) { + uint32_t mask = 0; + grpc_closure *cur; + int requested; + /* keep track of pollers that have requested our events, in case they change + */ + GRPC_FD_REF(fd, "poll"); + + gpr_mu_lock(&fd->mu); + + /* if we are shutdown, then don't add to the watcher set */ + if (fd->shutdown) { + watcher->fd = NULL; + watcher->pollset = NULL; + watcher->worker = NULL; + gpr_mu_unlock(&fd->mu); + GRPC_FD_UNREF(fd, "poll"); + return 0; + } + + /* if there is nobody polling for read, but we need to, then start doing so */ + cur = fd->read_closure; + requested = cur != CLOSURE_READY; + if (read_mask && fd->read_watcher == NULL && requested) { + fd->read_watcher = watcher; + mask |= read_mask; + } + /* if there is nobody polling for write, but we need to, then start doing so + */ + cur = fd->write_closure; + requested = cur != CLOSURE_READY; + if (write_mask && fd->write_watcher == NULL && requested) { + fd->write_watcher = watcher; + mask |= write_mask; + } + /* if not polling, remember this watcher in case we need someone to later */ + if (mask == 0 && worker != NULL) { + watcher->next = &fd->inactive_watcher_root; + watcher->prev = watcher->next->prev; + watcher->next->prev = watcher->prev->next = watcher; + } + watcher->pollset = pollset; + watcher->worker = worker; + watcher->fd = fd; + gpr_mu_unlock(&fd->mu); + + return mask; +} + +static void fd_end_poll(grpc_exec_ctx *exec_ctx, grpc_fd_watcher *watcher, + int got_read, int got_write, + grpc_pollset *read_notifier_pollset) { + int was_polling = 0; + int kick = 0; + grpc_fd *fd = watcher->fd; + + if (fd == NULL) { + return; + } + + gpr_mu_lock(&fd->mu); + + if (watcher == fd->read_watcher) { + /* remove read watcher, kick if we still need a read */ + was_polling = 1; + if (!got_read) { + kick = 1; + } + fd->read_watcher = NULL; + } + if (watcher == fd->write_watcher) { + /* remove write watcher, kick if we still need a write */ + was_polling = 1; + if (!got_write) { + kick = 1; + } + fd->write_watcher = NULL; + } + if (!was_polling && watcher->worker != NULL) { + /* remove from inactive list */ + watcher->next->prev = watcher->prev; + watcher->prev->next = watcher->next; + } + if (got_read) { + if (set_ready_locked(exec_ctx, fd, &fd->read_closure)) { + kick = 1; + } + if (read_notifier_pollset != NULL) { + set_read_notifier_pollset_locked(exec_ctx, fd, read_notifier_pollset); + } + } + if (got_write) { + if (set_ready_locked(exec_ctx, fd, &fd->write_closure)) { + kick = 1; + } + } + if (kick) { + maybe_wake_one_watcher_locked(fd); + } + if (fd_is_orphaned(fd) && !has_watchers(fd) && !fd->closed) { + close_fd_locked(exec_ctx, fd); + } + gpr_mu_unlock(&fd->mu); + + GRPC_FD_UNREF(fd, "poll"); +} + +/******************************************************************************* + * pollset_posix.c + */ + +GPR_TLS_DECL(g_current_thread_poller); +GPR_TLS_DECL(g_current_thread_worker); + +static void remove_worker(grpc_pollset *p, grpc_pollset_worker *worker) { + worker->prev->next = worker->next; + worker->next->prev = worker->prev; +} + +static int pollset_has_workers(grpc_pollset *p) { + return p->root_worker.next != &p->root_worker; +} + +static grpc_pollset_worker *pop_front_worker(grpc_pollset *p) { + if (pollset_has_workers(p)) { + grpc_pollset_worker *w = p->root_worker.next; + remove_worker(p, w); + return w; + } else { + return NULL; + } +} + +static void push_back_worker(grpc_pollset *p, grpc_pollset_worker *worker) { + worker->next = &p->root_worker; + worker->prev = worker->next->prev; + worker->prev->next = worker->next->prev = worker; +} + +static void push_front_worker(grpc_pollset *p, grpc_pollset_worker *worker) { + worker->prev = &p->root_worker; + worker->next = worker->prev->next; + worker->prev->next = worker->next->prev = worker; +} + +static void kick_append_error(grpc_error **composite, grpc_error *error) { + if (error == GRPC_ERROR_NONE) return; + if (*composite == GRPC_ERROR_NONE) { + *composite = GRPC_ERROR_CREATE("Kick Failure"); + } + *composite = grpc_error_add_child(*composite, error); +} + +static grpc_error *pollset_kick_ext(grpc_pollset *p, + grpc_pollset_worker *specific_worker, + uint32_t flags) { + GPR_TIMER_BEGIN("pollset_kick_ext", 0); + grpc_error *error = GRPC_ERROR_NONE; + + /* pollset->mu already held */ + if (specific_worker != NULL) { + if (specific_worker == GRPC_POLLSET_KICK_BROADCAST) { + GPR_TIMER_BEGIN("pollset_kick_ext.broadcast", 0); + GPR_ASSERT((flags & GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP) == 0); + for (specific_worker = p->root_worker.next; + specific_worker != &p->root_worker; + specific_worker = specific_worker->next) { + kick_append_error( + &error, grpc_wakeup_fd_wakeup(&specific_worker->wakeup_fd->fd)); + } + p->kicked_without_pollers = true; + GPR_TIMER_END("pollset_kick_ext.broadcast", 0); + } else if (gpr_tls_get(&g_current_thread_worker) != + (intptr_t)specific_worker) { + GPR_TIMER_MARK("different_thread_worker", 0); + if ((flags & GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP) != 0) { + specific_worker->reevaluate_polling_on_wakeup = true; + } + specific_worker->kicked_specifically = true; + kick_append_error(&error, + grpc_wakeup_fd_wakeup(&specific_worker->wakeup_fd->fd)); + } else if ((flags & GRPC_POLLSET_CAN_KICK_SELF) != 0) { + GPR_TIMER_MARK("kick_yoself", 0); + if ((flags & GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP) != 0) { + specific_worker->reevaluate_polling_on_wakeup = true; + } + specific_worker->kicked_specifically = true; + kick_append_error(&error, + grpc_wakeup_fd_wakeup(&specific_worker->wakeup_fd->fd)); + } + } else if (gpr_tls_get(&g_current_thread_poller) != (intptr_t)p) { + GPR_ASSERT((flags & GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP) == 0); + GPR_TIMER_MARK("kick_anonymous", 0); + specific_worker = pop_front_worker(p); + if (specific_worker != NULL) { + if (gpr_tls_get(&g_current_thread_worker) == (intptr_t)specific_worker) { + GPR_TIMER_MARK("kick_anonymous_not_self", 0); + push_back_worker(p, specific_worker); + specific_worker = pop_front_worker(p); + if ((flags & GRPC_POLLSET_CAN_KICK_SELF) == 0 && + gpr_tls_get(&g_current_thread_worker) == + (intptr_t)specific_worker) { + push_back_worker(p, specific_worker); + specific_worker = NULL; + } + } + if (specific_worker != NULL) { + GPR_TIMER_MARK("finally_kick", 0); + push_back_worker(p, specific_worker); + kick_append_error( + &error, grpc_wakeup_fd_wakeup(&specific_worker->wakeup_fd->fd)); + } + } else { + GPR_TIMER_MARK("kicked_no_pollers", 0); + p->kicked_without_pollers = true; + } + } + + GPR_TIMER_END("pollset_kick_ext", 0); + GRPC_LOG_IF_ERROR("pollset_kick_ext", GRPC_ERROR_REF(error)); + return error; +} + +static grpc_error *pollset_kick(grpc_pollset *p, + grpc_pollset_worker *specific_worker) { + return pollset_kick_ext(p, specific_worker, 0); +} + +/* global state management */ + +static grpc_error *pollset_global_init(void) { + gpr_tls_init(&g_current_thread_poller); + gpr_tls_init(&g_current_thread_worker); + return grpc_wakeup_fd_init(&grpc_global_wakeup_fd); +} + +static void pollset_global_shutdown(void) { + grpc_wakeup_fd_destroy(&grpc_global_wakeup_fd); + gpr_tls_destroy(&g_current_thread_poller); + gpr_tls_destroy(&g_current_thread_worker); +} + +static grpc_error *kick_poller(void) { + return grpc_wakeup_fd_wakeup(&grpc_global_wakeup_fd); +} + +/* main interface */ + +static void pollset_init(grpc_pollset *pollset, gpr_mu **mu) { + gpr_mu_init(&pollset->mu); + *mu = &pollset->mu; + pollset->root_worker.next = pollset->root_worker.prev = &pollset->root_worker; + pollset->shutting_down = 0; + pollset->called_shutdown = 0; + pollset->kicked_without_pollers = 0; + pollset->idle_jobs.head = pollset->idle_jobs.tail = NULL; + pollset->local_wakeup_cache = NULL; + pollset->kicked_without_pollers = 0; + pollset->fd_count = 0; + pollset->fd_capacity = 0; + pollset->fds = NULL; +} + +static void pollset_destroy(grpc_pollset *pollset) { + GPR_ASSERT(!pollset_has_workers(pollset)); + GPR_ASSERT(pollset->idle_jobs.head == pollset->idle_jobs.tail); + while (pollset->local_wakeup_cache) { + grpc_cached_wakeup_fd *next = pollset->local_wakeup_cache->next; + grpc_wakeup_fd_destroy(&pollset->local_wakeup_cache->fd); + gpr_free(pollset->local_wakeup_cache); + pollset->local_wakeup_cache = next; + } + gpr_free(pollset->fds); + gpr_mu_destroy(&pollset->mu); +} + +static void pollset_reset(grpc_pollset *pollset) { + GPR_ASSERT(pollset->shutting_down); + GPR_ASSERT(!pollset_has_workers(pollset)); + GPR_ASSERT(pollset->idle_jobs.head == pollset->idle_jobs.tail); + GPR_ASSERT(pollset->fd_count == 0); + pollset->shutting_down = 0; + pollset->called_shutdown = 0; + pollset->kicked_without_pollers = 0; +} + +static void pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + grpc_fd *fd) { + gpr_mu_lock(&pollset->mu); + size_t i; + /* TODO(ctiller): this is O(num_fds^2); maybe switch to a hash set here */ + for (i = 0; i < pollset->fd_count; i++) { + if (pollset->fds[i] == fd) goto exit; + } + if (pollset->fd_count == pollset->fd_capacity) { + pollset->fd_capacity = + GPR_MAX(pollset->fd_capacity + 8, pollset->fd_count * 3 / 2); + pollset->fds = + gpr_realloc(pollset->fds, sizeof(grpc_fd *) * pollset->fd_capacity); + } + pollset->fds[pollset->fd_count++] = fd; + GRPC_FD_REF(fd, "multipoller"); + pollset_kick(pollset, NULL); +exit: + gpr_mu_unlock(&pollset->mu); +} + +static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) { + GPR_ASSERT(grpc_closure_list_empty(pollset->idle_jobs)); + size_t i; + for (i = 0; i < pollset->fd_count; i++) { + GRPC_FD_UNREF(pollset->fds[i], "multipoller"); + } + pollset->fd_count = 0; + grpc_exec_ctx_sched(exec_ctx, pollset->shutdown_done, GRPC_ERROR_NONE, NULL); +} + +static void work_combine_error(grpc_error **composite, grpc_error *error) { + if (error == GRPC_ERROR_NONE) return; + if (*composite == GRPC_ERROR_NONE) { + *composite = GRPC_ERROR_CREATE("pollset_work"); + } + *composite = grpc_error_add_child(*composite, error); +} + +static grpc_error *pollset_work(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + grpc_pollset_worker **worker_hdl, + gpr_timespec now, gpr_timespec deadline) { + grpc_pollset_worker worker; + *worker_hdl = &worker; + grpc_error *error = GRPC_ERROR_NONE; + + /* pollset->mu already held */ + int added_worker = 0; + int locked = 1; + int queued_work = 0; + int keep_polling = 0; + GPR_TIMER_BEGIN("pollset_work", 0); + /* this must happen before we (potentially) drop pollset->mu */ + worker.next = worker.prev = NULL; + worker.reevaluate_polling_on_wakeup = 0; + if (pollset->local_wakeup_cache != NULL) { + worker.wakeup_fd = pollset->local_wakeup_cache; + pollset->local_wakeup_cache = worker.wakeup_fd->next; + } else { + worker.wakeup_fd = gpr_malloc(sizeof(*worker.wakeup_fd)); + error = grpc_wakeup_fd_init(&worker.wakeup_fd->fd); + if (error != GRPC_ERROR_NONE) { + GRPC_LOG_IF_ERROR("pollset_work", GRPC_ERROR_REF(error)); + return error; + } + } + worker.kicked_specifically = 0; + /* If there's work waiting for the pollset to be idle, and the + pollset is idle, then do that work */ + if (!pollset_has_workers(pollset) && + !grpc_closure_list_empty(pollset->idle_jobs)) { + GPR_TIMER_MARK("pollset_work.idle_jobs", 0); + grpc_exec_ctx_enqueue_list(exec_ctx, &pollset->idle_jobs, NULL); + goto done; + } + /* If we're shutting down then we don't execute any extended work */ + if (pollset->shutting_down) { + GPR_TIMER_MARK("pollset_work.shutting_down", 0); + goto done; + } + /* Start polling, and keep doing so while we're being asked to + re-evaluate our pollers (this allows poll() based pollers to + ensure they don't miss wakeups) */ + keep_polling = 1; + gpr_tls_set(&g_current_thread_poller, (intptr_t)pollset); + while (keep_polling) { + keep_polling = 0; + if (!pollset->kicked_without_pollers) { + if (!added_worker) { + push_front_worker(pollset, &worker); + added_worker = 1; + gpr_tls_set(&g_current_thread_worker, (intptr_t)&worker); + } + GPR_TIMER_BEGIN("maybe_work_and_unlock", 0); +#define POLLOUT_CHECK (POLLOUT | POLLHUP | POLLERR) +#define POLLIN_CHECK (POLLIN | POLLHUP | POLLERR) + + int timeout; + int r; + size_t i, fd_count; + nfds_t pfd_count; + /* TODO(ctiller): inline some elements to avoid an allocation */ + grpc_fd_watcher *watchers; + struct pollfd *pfds; + + timeout = poll_deadline_to_millis_timeout(deadline, now); + /* TODO(ctiller): perform just one malloc here if we exceed the inline + * case */ + pfds = gpr_malloc(sizeof(*pfds) * (pollset->fd_count + 2)); + watchers = gpr_malloc(sizeof(*watchers) * (pollset->fd_count + 2)); + fd_count = 0; + pfd_count = 2; + pfds[0].fd = GRPC_WAKEUP_FD_GET_READ_FD(&grpc_global_wakeup_fd); + pfds[0].events = POLLIN; + pfds[0].revents = 0; + pfds[1].fd = GRPC_WAKEUP_FD_GET_READ_FD(&worker.wakeup_fd->fd); + pfds[1].events = POLLIN; + pfds[1].revents = 0; + for (i = 0; i < pollset->fd_count; i++) { + if (fd_is_orphaned(pollset->fds[i])) { + GRPC_FD_UNREF(pollset->fds[i], "multipoller"); + } else { + pollset->fds[fd_count++] = pollset->fds[i]; + watchers[pfd_count].fd = pollset->fds[i]; + GRPC_FD_REF(watchers[pfd_count].fd, "multipoller_start"); + pfds[pfd_count].fd = pollset->fds[i]->fd; + pfds[pfd_count].revents = 0; + pfd_count++; + } + } + pollset->fd_count = fd_count; + gpr_mu_unlock(&pollset->mu); + + for (i = 2; i < pfd_count; i++) { + grpc_fd *fd = watchers[i].fd; + pfds[i].events = (short)fd_begin_poll(fd, pollset, &worker, POLLIN, + POLLOUT, &watchers[i]); + GRPC_FD_UNREF(fd, "multipoller_start"); + } + + /* TODO(vpai): Consider first doing a 0 timeout poll here to avoid + even going into the blocking annotation if possible */ + GRPC_SCHEDULING_START_BLOCKING_REGION; + r = grpc_poll_function(pfds, pfd_count, timeout); + GRPC_SCHEDULING_END_BLOCKING_REGION; + + if (r < 0) { + if (errno != EINTR) { + work_combine_error(&error, GRPC_OS_ERROR(errno, "poll")); + } + for (i = 2; i < pfd_count; i++) { + fd_end_poll(exec_ctx, &watchers[i], 0, 0, NULL); + } + } else if (r == 0) { + for (i = 2; i < pfd_count; i++) { + fd_end_poll(exec_ctx, &watchers[i], 0, 0, NULL); + } + } else { + if (pfds[0].revents & POLLIN_CHECK) { + work_combine_error( + &error, grpc_wakeup_fd_consume_wakeup(&grpc_global_wakeup_fd)); + } + if (pfds[1].revents & POLLIN_CHECK) { + work_combine_error( + &error, grpc_wakeup_fd_consume_wakeup(&worker.wakeup_fd->fd)); + } + for (i = 2; i < pfd_count; i++) { + if (watchers[i].fd == NULL) { + fd_end_poll(exec_ctx, &watchers[i], 0, 0, NULL); + } else { + fd_end_poll(exec_ctx, &watchers[i], pfds[i].revents & POLLIN_CHECK, + pfds[i].revents & POLLOUT_CHECK, pollset); + } + } + } + + gpr_free(pfds); + gpr_free(watchers); + GPR_TIMER_END("maybe_work_and_unlock", 0); + locked = 0; + } else { + GPR_TIMER_MARK("pollset_work.kicked_without_pollers", 0); + pollset->kicked_without_pollers = 0; + } + /* Finished execution - start cleaning up. + Note that we may arrive here from outside the enclosing while() loop. + In that case we won't loop though as we haven't added worker to the + worker list, which means nobody could ask us to re-evaluate polling). */ + done: + if (!locked) { + queued_work |= grpc_exec_ctx_flush(exec_ctx); + gpr_mu_lock(&pollset->mu); + locked = 1; + } + /* If we're forced to re-evaluate polling (via pollset_kick with + GRPC_POLLSET_REEVALUATE_POLLING_ON_WAKEUP) then we land here and force + a loop */ + if (worker.reevaluate_polling_on_wakeup && error == GRPC_ERROR_NONE) { + worker.reevaluate_polling_on_wakeup = 0; + pollset->kicked_without_pollers = 0; + if (queued_work || worker.kicked_specifically) { + /* If there's queued work on the list, then set the deadline to be + immediate so we get back out of the polling loop quickly */ + deadline = gpr_inf_past(GPR_CLOCK_MONOTONIC); + } + keep_polling = 1; + } + if (keep_polling) { + now = gpr_now(now.clock_type); + } + } + gpr_tls_set(&g_current_thread_poller, 0); + if (added_worker) { + remove_worker(pollset, &worker); + gpr_tls_set(&g_current_thread_worker, 0); + } + /* release wakeup fd to the local pool */ + worker.wakeup_fd->next = pollset->local_wakeup_cache; + pollset->local_wakeup_cache = worker.wakeup_fd; + /* check shutdown conditions */ + if (pollset->shutting_down) { + if (pollset_has_workers(pollset)) { + pollset_kick(pollset, NULL); + } else if (!pollset->called_shutdown) { + pollset->called_shutdown = 1; + gpr_mu_unlock(&pollset->mu); + finish_shutdown(exec_ctx, pollset); + grpc_exec_ctx_flush(exec_ctx); + /* Continuing to access pollset here is safe -- it is the caller's + * responsibility to not destroy when it has outstanding calls to + * pollset_work. + * TODO(dklempner): Can we refactor the shutdown logic to avoid this? */ + gpr_mu_lock(&pollset->mu); + } else if (!grpc_closure_list_empty(pollset->idle_jobs)) { + grpc_exec_ctx_enqueue_list(exec_ctx, &pollset->idle_jobs, NULL); + gpr_mu_unlock(&pollset->mu); + grpc_exec_ctx_flush(exec_ctx); + gpr_mu_lock(&pollset->mu); + } + } + *worker_hdl = NULL; + GPR_TIMER_END("pollset_work", 0); + GRPC_LOG_IF_ERROR("pollset_work", GRPC_ERROR_REF(error)); + return error; +} + +static void pollset_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + grpc_closure *closure) { + GPR_ASSERT(!pollset->shutting_down); + pollset->shutting_down = 1; + pollset->shutdown_done = closure; + pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST); + if (!pollset_has_workers(pollset)) { + grpc_exec_ctx_enqueue_list(exec_ctx, &pollset->idle_jobs, NULL); + } + if (!pollset->called_shutdown && !pollset_has_workers(pollset)) { + pollset->called_shutdown = 1; + finish_shutdown(exec_ctx, pollset); + } +} + +static int poll_deadline_to_millis_timeout(gpr_timespec deadline, + gpr_timespec now) { + gpr_timespec timeout; + static const int64_t max_spin_polling_us = 10; + if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) == 0) { + return -1; + } + if (gpr_time_cmp(deadline, gpr_time_add(now, gpr_time_from_micros( + max_spin_polling_us, + GPR_TIMESPAN))) <= 0) { + return 0; + } + timeout = gpr_time_sub(deadline, now); + return gpr_time_to_millis(gpr_time_add( + timeout, gpr_time_from_nanos(GPR_NS_PER_MS - 1, GPR_TIMESPAN))); +} + +/******************************************************************************* + * pollset_set_posix.c + */ + +static grpc_pollset_set *pollset_set_create(void) { + grpc_pollset_set *pollset_set = gpr_malloc(sizeof(*pollset_set)); + memset(pollset_set, 0, sizeof(*pollset_set)); + gpr_mu_init(&pollset_set->mu); + return pollset_set; +} + +static void pollset_set_destroy(grpc_pollset_set *pollset_set) { + size_t i; + gpr_mu_destroy(&pollset_set->mu); + for (i = 0; i < pollset_set->fd_count; i++) { + GRPC_FD_UNREF(pollset_set->fds[i], "pollset_set"); + } + gpr_free(pollset_set->pollsets); + gpr_free(pollset_set->pollset_sets); + gpr_free(pollset_set->fds); + gpr_free(pollset_set); +} + +static void pollset_set_add_pollset(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *pollset_set, + grpc_pollset *pollset) { + size_t i, j; + gpr_mu_lock(&pollset_set->mu); + if (pollset_set->pollset_count == pollset_set->pollset_capacity) { + pollset_set->pollset_capacity = + GPR_MAX(8, 2 * pollset_set->pollset_capacity); + pollset_set->pollsets = + gpr_realloc(pollset_set->pollsets, pollset_set->pollset_capacity * + sizeof(*pollset_set->pollsets)); + } + pollset_set->pollsets[pollset_set->pollset_count++] = pollset; + for (i = 0, j = 0; i < pollset_set->fd_count; i++) { + if (fd_is_orphaned(pollset_set->fds[i])) { + GRPC_FD_UNREF(pollset_set->fds[i], "pollset_set"); + } else { + pollset_add_fd(exec_ctx, pollset, pollset_set->fds[i]); + pollset_set->fds[j++] = pollset_set->fds[i]; + } + } + pollset_set->fd_count = j; + gpr_mu_unlock(&pollset_set->mu); +} + +static void pollset_set_del_pollset(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *pollset_set, + grpc_pollset *pollset) { + size_t i; + gpr_mu_lock(&pollset_set->mu); + for (i = 0; i < pollset_set->pollset_count; i++) { + if (pollset_set->pollsets[i] == pollset) { + pollset_set->pollset_count--; + GPR_SWAP(grpc_pollset *, pollset_set->pollsets[i], + pollset_set->pollsets[pollset_set->pollset_count]); + break; + } + } + gpr_mu_unlock(&pollset_set->mu); +} + +static void pollset_set_add_pollset_set(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *bag, + grpc_pollset_set *item) { + size_t i, j; + gpr_mu_lock(&bag->mu); + if (bag->pollset_set_count == bag->pollset_set_capacity) { + bag->pollset_set_capacity = GPR_MAX(8, 2 * bag->pollset_set_capacity); + bag->pollset_sets = + gpr_realloc(bag->pollset_sets, + bag->pollset_set_capacity * sizeof(*bag->pollset_sets)); + } + bag->pollset_sets[bag->pollset_set_count++] = item; + for (i = 0, j = 0; i < bag->fd_count; i++) { + if (fd_is_orphaned(bag->fds[i])) { + GRPC_FD_UNREF(bag->fds[i], "pollset_set"); + } else { + pollset_set_add_fd(exec_ctx, item, bag->fds[i]); + bag->fds[j++] = bag->fds[i]; + } + } + bag->fd_count = j; + gpr_mu_unlock(&bag->mu); +} + +static void pollset_set_del_pollset_set(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *bag, + grpc_pollset_set *item) { + size_t i; + gpr_mu_lock(&bag->mu); + for (i = 0; i < bag->pollset_set_count; i++) { + if (bag->pollset_sets[i] == item) { + bag->pollset_set_count--; + GPR_SWAP(grpc_pollset_set *, bag->pollset_sets[i], + bag->pollset_sets[bag->pollset_set_count]); + break; + } + } + gpr_mu_unlock(&bag->mu); +} + +static void pollset_set_add_fd(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *pollset_set, grpc_fd *fd) { + size_t i; + gpr_mu_lock(&pollset_set->mu); + if (pollset_set->fd_count == pollset_set->fd_capacity) { + pollset_set->fd_capacity = GPR_MAX(8, 2 * pollset_set->fd_capacity); + pollset_set->fds = gpr_realloc( + pollset_set->fds, pollset_set->fd_capacity * sizeof(*pollset_set->fds)); + } + GRPC_FD_REF(fd, "pollset_set"); + pollset_set->fds[pollset_set->fd_count++] = fd; + for (i = 0; i < pollset_set->pollset_count; i++) { + pollset_add_fd(exec_ctx, pollset_set->pollsets[i], fd); + } + for (i = 0; i < pollset_set->pollset_set_count; i++) { + pollset_set_add_fd(exec_ctx, pollset_set->pollset_sets[i], fd); + } + gpr_mu_unlock(&pollset_set->mu); +} + +static void pollset_set_del_fd(grpc_exec_ctx *exec_ctx, + grpc_pollset_set *pollset_set, grpc_fd *fd) { + size_t i; + gpr_mu_lock(&pollset_set->mu); + for (i = 0; i < pollset_set->fd_count; i++) { + if (pollset_set->fds[i] == fd) { + pollset_set->fd_count--; + GPR_SWAP(grpc_fd *, pollset_set->fds[i], + pollset_set->fds[pollset_set->fd_count]); + GRPC_FD_UNREF(fd, "pollset_set"); + break; + } + } + for (i = 0; i < pollset_set->pollset_set_count; i++) { + pollset_set_del_fd(exec_ctx, pollset_set->pollset_sets[i], fd); + } + gpr_mu_unlock(&pollset_set->mu); +} + +/******************************************************************************* + * event engine binding + */ + +static void shutdown_engine(void) { pollset_global_shutdown(); } + +static const grpc_event_engine_vtable vtable = { + .pollset_size = sizeof(grpc_pollset), + + .fd_create = fd_create, + .fd_wrapped_fd = fd_wrapped_fd, + .fd_orphan = fd_orphan, + .fd_shutdown = fd_shutdown, + .fd_is_shutdown = fd_is_shutdown, + .fd_notify_on_read = fd_notify_on_read, + .fd_notify_on_write = fd_notify_on_write, + .fd_get_read_notifier_pollset = fd_get_read_notifier_pollset, + + .pollset_init = pollset_init, + .pollset_shutdown = pollset_shutdown, + .pollset_reset = pollset_reset, + .pollset_destroy = pollset_destroy, + .pollset_work = pollset_work, + .pollset_kick = pollset_kick, + .pollset_add_fd = pollset_add_fd, + + .pollset_set_create = pollset_set_create, + .pollset_set_destroy = pollset_set_destroy, + .pollset_set_add_pollset = pollset_set_add_pollset, + .pollset_set_del_pollset = pollset_set_del_pollset, + .pollset_set_add_pollset_set = pollset_set_add_pollset_set, + .pollset_set_del_pollset_set = pollset_set_del_pollset_set, + .pollset_set_add_fd = pollset_set_add_fd, + .pollset_set_del_fd = pollset_set_del_fd, + + .kick_poller = kick_poller, + + .shutdown_engine = shutdown_engine, +}; + +const grpc_event_engine_vtable *grpc_init_poll_posix(void) { + if (!GRPC_LOG_IF_ERROR("pollset_global_init", pollset_global_init())) { + return NULL; + } + return &vtable; +} + +#endif |