| /* |
| * |
| * Copyright 2015, 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 "src/core/surface/completion_queue.h" |
| |
| #include <stdio.h> |
| #include <string.h> |
| |
| #include "src/core/iomgr/pollset.h" |
| #include "src/core/support/string.h" |
| #include "src/core/surface/call.h" |
| #include "src/core/surface/event_string.h" |
| #include "src/core/surface/surface_trace.h" |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/atm.h> |
| #include <grpc/support/log.h> |
| |
| #define NUM_TAG_BUCKETS 31 |
| |
| /* A single event: extends grpc_event to form a linked list with a destruction |
| function (on_finish) that is hidden from outside this module */ |
| typedef struct event { |
| grpc_event base; |
| grpc_event_finish_func on_finish; |
| void *on_finish_user_data; |
| struct event *queue_next; |
| struct event *queue_prev; |
| struct event *bucket_next; |
| struct event *bucket_prev; |
| } event; |
| |
| /* Completion queue structure */ |
| struct grpc_completion_queue { |
| /* TODO(ctiller): see if this can be removed */ |
| int allow_polling; |
| |
| /* When refs drops to zero, we are in shutdown mode, and will be destroyable |
| once all queued events are drained */ |
| gpr_refcount refs; |
| /* the set of low level i/o things that concern this cq */ |
| grpc_pollset pollset; |
| /* 0 initially, 1 once we've begun shutting down */ |
| int shutdown; |
| int shutdown_called; |
| /* Head of a linked list of queued events (prev points to the last element) */ |
| event *queue; |
| /* Fixed size chained hash table of events for pluck() */ |
| event *buckets[NUM_TAG_BUCKETS]; |
| |
| #ifndef NDEBUG |
| /* Debug support: track which operations are in flight at any given time */ |
| gpr_atm pending_op_count[GRPC_COMPLETION_DO_NOT_USE]; |
| #endif |
| }; |
| |
| /* Default do-nothing on_finish function */ |
| static void null_on_finish(void *user_data, grpc_op_error error) {} |
| |
| grpc_completion_queue *grpc_completion_queue_create(void) { |
| grpc_completion_queue *cc = gpr_malloc(sizeof(grpc_completion_queue)); |
| memset(cc, 0, sizeof(*cc)); |
| /* Initial ref is dropped by grpc_completion_queue_shutdown */ |
| gpr_ref_init(&cc->refs, 1); |
| grpc_pollset_init(&cc->pollset); |
| cc->allow_polling = 1; |
| return cc; |
| } |
| |
| void grpc_completion_queue_dont_poll_test_only(grpc_completion_queue *cc) { |
| cc->allow_polling = 0; |
| } |
| |
| /* Create and append an event to the queue. Returns the event so that its data |
| members can be filled in. |
| Requires GRPC_POLLSET_MU(&cc->pollset) locked. */ |
| static event *add_locked(grpc_completion_queue *cc, grpc_completion_type type, |
| void *tag, grpc_call *call, |
| grpc_event_finish_func on_finish, void *user_data) { |
| event *ev = gpr_malloc(sizeof(event)); |
| gpr_uintptr bucket = ((gpr_uintptr)tag) % NUM_TAG_BUCKETS; |
| ev->base.type = type; |
| ev->base.tag = tag; |
| ev->base.call = call; |
| ev->on_finish = on_finish ? on_finish : null_on_finish; |
| ev->on_finish_user_data = user_data; |
| if (cc->queue == NULL) { |
| cc->queue = ev->queue_next = ev->queue_prev = ev; |
| } else { |
| ev->queue_next = cc->queue; |
| ev->queue_prev = cc->queue->queue_prev; |
| ev->queue_next->queue_prev = ev->queue_prev->queue_next = ev; |
| } |
| if (cc->buckets[bucket] == NULL) { |
| cc->buckets[bucket] = ev->bucket_next = ev->bucket_prev = ev; |
| } else { |
| ev->bucket_next = cc->buckets[bucket]; |
| ev->bucket_prev = cc->buckets[bucket]->bucket_prev; |
| ev->bucket_next->bucket_prev = ev->bucket_prev->bucket_next = ev; |
| } |
| gpr_cv_broadcast(GRPC_POLLSET_CV(&cc->pollset)); |
| grpc_pollset_kick(&cc->pollset); |
| return ev; |
| } |
| |
| void grpc_cq_begin_op(grpc_completion_queue *cc, grpc_call *call, |
| grpc_completion_type type) { |
| gpr_ref(&cc->refs); |
| if (call) grpc_call_internal_ref(call); |
| #ifndef NDEBUG |
| gpr_atm_no_barrier_fetch_add(&cc->pending_op_count[type], 1); |
| #endif |
| } |
| |
| /* Signal the end of an operation - if this is the last waiting-to-be-queued |
| event, then enter shutdown mode */ |
| static void end_op_locked(grpc_completion_queue *cc, |
| grpc_completion_type type) { |
| #ifndef NDEBUG |
| GPR_ASSERT(gpr_atm_full_fetch_add(&cc->pending_op_count[type], -1) > 0); |
| #endif |
| if (gpr_unref(&cc->refs)) { |
| GPR_ASSERT(!cc->shutdown); |
| GPR_ASSERT(cc->shutdown_called); |
| cc->shutdown = 1; |
| gpr_cv_broadcast(GRPC_POLLSET_CV(&cc->pollset)); |
| } |
| } |
| |
| void grpc_cq_end_server_shutdown(grpc_completion_queue *cc, void *tag) { |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| add_locked(cc, GRPC_SERVER_SHUTDOWN, tag, NULL, NULL, NULL); |
| end_op_locked(cc, GRPC_SERVER_SHUTDOWN); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_read(grpc_completion_queue *cc, void *tag, grpc_call *call, |
| grpc_event_finish_func on_finish, void *user_data, |
| grpc_byte_buffer *read) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_READ, tag, call, on_finish, user_data); |
| ev->base.data.read = read; |
| end_op_locked(cc, GRPC_READ); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_write_accepted(grpc_completion_queue *cc, void *tag, |
| grpc_call *call, |
| grpc_event_finish_func on_finish, |
| void *user_data, grpc_op_error error) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_WRITE_ACCEPTED, tag, call, on_finish, user_data); |
| ev->base.data.write_accepted = error; |
| end_op_locked(cc, GRPC_WRITE_ACCEPTED); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_op_complete(grpc_completion_queue *cc, void *tag, |
| grpc_call *call, grpc_event_finish_func on_finish, |
| void *user_data, grpc_op_error error) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_OP_COMPLETE, tag, call, on_finish, user_data); |
| ev->base.data.write_accepted = error; |
| end_op_locked(cc, GRPC_OP_COMPLETE); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_op(grpc_completion_queue *cc, void *tag, grpc_call *call, |
| grpc_event_finish_func on_finish, void *user_data, |
| grpc_op_error error) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_OP_COMPLETE, tag, call, on_finish, user_data); |
| ev->base.data.write_accepted = error; |
| end_op_locked(cc, GRPC_OP_COMPLETE); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_finish_accepted(grpc_completion_queue *cc, void *tag, |
| grpc_call *call, |
| grpc_event_finish_func on_finish, |
| void *user_data, grpc_op_error error) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_FINISH_ACCEPTED, tag, call, on_finish, user_data); |
| ev->base.data.finish_accepted = error; |
| end_op_locked(cc, GRPC_FINISH_ACCEPTED); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_client_metadata_read(grpc_completion_queue *cc, void *tag, |
| grpc_call *call, |
| grpc_event_finish_func on_finish, |
| void *user_data, size_t count, |
| grpc_metadata *elements) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_CLIENT_METADATA_READ, tag, call, on_finish, |
| user_data); |
| ev->base.data.client_metadata_read.count = count; |
| ev->base.data.client_metadata_read.elements = elements; |
| end_op_locked(cc, GRPC_CLIENT_METADATA_READ); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_finished(grpc_completion_queue *cc, void *tag, grpc_call *call, |
| grpc_event_finish_func on_finish, void *user_data, |
| grpc_status_code status, const char *details, |
| grpc_metadata *metadata_elements, |
| size_t metadata_count) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_FINISHED, tag, call, on_finish, user_data); |
| ev->base.data.finished.status = status; |
| ev->base.data.finished.details = details; |
| ev->base.data.finished.metadata_count = metadata_count; |
| ev->base.data.finished.metadata_elements = metadata_elements; |
| end_op_locked(cc, GRPC_FINISHED); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| void grpc_cq_end_new_rpc(grpc_completion_queue *cc, void *tag, grpc_call *call, |
| grpc_event_finish_func on_finish, void *user_data, |
| const char *method, const char *host, |
| gpr_timespec deadline, size_t metadata_count, |
| grpc_metadata *metadata_elements) { |
| event *ev; |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| ev = add_locked(cc, GRPC_SERVER_RPC_NEW, tag, call, on_finish, user_data); |
| ev->base.data.server_rpc_new.method = method; |
| ev->base.data.server_rpc_new.host = host; |
| ev->base.data.server_rpc_new.deadline = deadline; |
| ev->base.data.server_rpc_new.metadata_count = metadata_count; |
| ev->base.data.server_rpc_new.metadata_elements = metadata_elements; |
| end_op_locked(cc, GRPC_SERVER_RPC_NEW); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| |
| /* Create a GRPC_QUEUE_SHUTDOWN event without queuing it anywhere */ |
| static event *create_shutdown_event(void) { |
| event *ev = gpr_malloc(sizeof(event)); |
| ev->base.type = GRPC_QUEUE_SHUTDOWN; |
| ev->base.call = NULL; |
| ev->base.tag = NULL; |
| ev->on_finish = null_on_finish; |
| return ev; |
| } |
| |
| grpc_event *grpc_completion_queue_next(grpc_completion_queue *cc, |
| gpr_timespec deadline) { |
| event *ev = NULL; |
| |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| for (;;) { |
| if (cc->queue != NULL) { |
| gpr_uintptr bucket; |
| ev = cc->queue; |
| bucket = ((gpr_uintptr)ev->base.tag) % NUM_TAG_BUCKETS; |
| cc->queue = ev->queue_next; |
| ev->queue_next->queue_prev = ev->queue_prev; |
| ev->queue_prev->queue_next = ev->queue_next; |
| ev->bucket_next->bucket_prev = ev->bucket_prev; |
| ev->bucket_prev->bucket_next = ev->bucket_next; |
| if (ev == cc->buckets[bucket]) { |
| cc->buckets[bucket] = ev->bucket_next; |
| if (ev == cc->buckets[bucket]) { |
| cc->buckets[bucket] = NULL; |
| } |
| } |
| if (cc->queue == ev) { |
| cc->queue = NULL; |
| } |
| break; |
| } |
| if (cc->shutdown) { |
| ev = create_shutdown_event(); |
| break; |
| } |
| if (cc->allow_polling && grpc_pollset_work(&cc->pollset, deadline)) { |
| continue; |
| } |
| if (gpr_cv_wait(GRPC_POLLSET_CV(&cc->pollset), |
| GRPC_POLLSET_MU(&cc->pollset), deadline)) { |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| return NULL; |
| } |
| } |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| GRPC_SURFACE_TRACE_RETURNED_EVENT(cc, &ev->base); |
| return &ev->base; |
| } |
| |
| static event *pluck_event(grpc_completion_queue *cc, void *tag) { |
| gpr_uintptr bucket = ((gpr_uintptr)tag) % NUM_TAG_BUCKETS; |
| event *ev = cc->buckets[bucket]; |
| if (ev == NULL) return NULL; |
| do { |
| if (ev->base.tag == tag) { |
| ev->queue_next->queue_prev = ev->queue_prev; |
| ev->queue_prev->queue_next = ev->queue_next; |
| ev->bucket_next->bucket_prev = ev->bucket_prev; |
| ev->bucket_prev->bucket_next = ev->bucket_next; |
| if (ev == cc->buckets[bucket]) { |
| cc->buckets[bucket] = ev->bucket_next; |
| if (ev == cc->buckets[bucket]) { |
| cc->buckets[bucket] = NULL; |
| } |
| } |
| if (cc->queue == ev) { |
| cc->queue = ev->queue_next; |
| if (cc->queue == ev) { |
| cc->queue = NULL; |
| } |
| } |
| return ev; |
| } |
| ev = ev->bucket_next; |
| } while (ev != cc->buckets[bucket]); |
| return NULL; |
| } |
| |
| grpc_event *grpc_completion_queue_pluck(grpc_completion_queue *cc, void *tag, |
| gpr_timespec deadline) { |
| event *ev = NULL; |
| |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| for (;;) { |
| if ((ev = pluck_event(cc, tag))) { |
| break; |
| } |
| if (cc->shutdown) { |
| ev = create_shutdown_event(); |
| break; |
| } |
| if (cc->allow_polling && grpc_pollset_work(&cc->pollset, deadline)) { |
| continue; |
| } |
| if (gpr_cv_wait(GRPC_POLLSET_CV(&cc->pollset), |
| GRPC_POLLSET_MU(&cc->pollset), deadline)) { |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| return NULL; |
| } |
| } |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| GRPC_SURFACE_TRACE_RETURNED_EVENT(cc, &ev->base); |
| return &ev->base; |
| } |
| |
| /* Shutdown simply drops a ref that we reserved at creation time; if we drop |
| to zero here, then enter shutdown mode and wake up any waiters */ |
| void grpc_completion_queue_shutdown(grpc_completion_queue *cc) { |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| cc->shutdown_called = 1; |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| |
| if (gpr_unref(&cc->refs)) { |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| GPR_ASSERT(!cc->shutdown); |
| cc->shutdown = 1; |
| gpr_cv_broadcast(GRPC_POLLSET_CV(&cc->pollset)); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |
| } |
| |
| static void on_pollset_destroy_done(void *arg) { |
| grpc_completion_queue *cc = arg; |
| grpc_pollset_destroy(&cc->pollset); |
| gpr_free(cc); |
| } |
| |
| void grpc_completion_queue_destroy(grpc_completion_queue *cc) { |
| GPR_ASSERT(cc->queue == NULL); |
| grpc_pollset_shutdown(&cc->pollset, on_pollset_destroy_done, cc); |
| } |
| |
| void grpc_event_finish(grpc_event *base) { |
| event *ev = (event *)base; |
| ev->on_finish(ev->on_finish_user_data, GRPC_OP_OK); |
| if (ev->base.call) { |
| grpc_call_internal_unref(ev->base.call, 1); |
| } |
| gpr_free(ev); |
| } |
| |
| void grpc_cq_dump_pending_ops(grpc_completion_queue *cc) { |
| #ifndef NDEBUG |
| char tmp[GRPC_COMPLETION_DO_NOT_USE * (1 + GPR_LTOA_MIN_BUFSIZE)]; |
| char *p = tmp; |
| int i; |
| |
| for (i = 0; i < GRPC_COMPLETION_DO_NOT_USE; i++) { |
| *p++ = ' '; |
| p += gpr_ltoa(cc->pending_op_count[i], p); |
| } |
| |
| gpr_log(GPR_INFO, "pending ops:%s", tmp); |
| #endif |
| } |
| |
| grpc_pollset *grpc_cq_pollset(grpc_completion_queue *cc) { |
| return &cc->pollset; |
| } |
| |
| void grpc_cq_hack_spin_pollset(grpc_completion_queue *cc) { |
| gpr_mu_lock(GRPC_POLLSET_MU(&cc->pollset)); |
| grpc_pollset_kick(&cc->pollset); |
| grpc_pollset_work(&cc->pollset, gpr_time_add(gpr_now(), gpr_time_from_millis(100))); |
| gpr_mu_unlock(GRPC_POLLSET_MU(&cc->pollset)); |
| } |