| /* |
| * |
| * Copyright 2015 gRPC authors. |
| * |
| * 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. |
| * |
| */ |
| |
| #ifndef GRPC_CORE_LIB_IOMGR_CLOSURE_H |
| #define GRPC_CORE_LIB_IOMGR_CLOSURE_H |
| |
| #include <grpc/support/port_platform.h> |
| |
| #include <assert.h> |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <stdbool.h> |
| #include "src/core/lib/gpr/mpscq.h" |
| #include "src/core/lib/iomgr/error.h" |
| #include "src/core/lib/profiling/timers.h" |
| |
| struct grpc_closure; |
| typedef struct grpc_closure grpc_closure; |
| |
| extern grpc_core::DebugOnlyTraceFlag grpc_trace_closure; |
| |
| typedef struct grpc_closure_list { |
| grpc_closure* head; |
| grpc_closure* tail; |
| } grpc_closure_list; |
| |
| /** gRPC Callback definition. |
| * |
| * \param arg Arbitrary input. |
| * \param error GRPC_ERROR_NONE if no error occurred, otherwise some grpc_error |
| * describing what went wrong. |
| * Error contract: it is not the cb's job to unref this error; |
| * the closure scheduler will do that after the cb returns */ |
| typedef void (*grpc_iomgr_cb_func)(void* arg, grpc_error* error); |
| |
| typedef struct grpc_closure_scheduler grpc_closure_scheduler; |
| |
| typedef struct grpc_closure_scheduler_vtable { |
| /* NOTE: for all these functions, closure->scheduler == the scheduler that was |
| used to find this vtable */ |
| void (*run)(grpc_closure* closure, grpc_error* error); |
| void (*sched)(grpc_closure* closure, grpc_error* error); |
| const char* name; |
| } grpc_closure_scheduler_vtable; |
| |
| /** Abstract type that can schedule closures for execution */ |
| struct grpc_closure_scheduler { |
| const grpc_closure_scheduler_vtable* vtable; |
| }; |
| |
| /** A closure over a grpc_iomgr_cb_func. */ |
| struct grpc_closure { |
| /** Once queued, next indicates the next queued closure; before then, scratch |
| * space */ |
| union { |
| grpc_closure* next; |
| gpr_mpscq_node atm_next; |
| uintptr_t scratch; |
| } next_data; |
| |
| /** Bound callback. */ |
| grpc_iomgr_cb_func cb; |
| |
| /** Arguments to be passed to "cb". */ |
| void* cb_arg; |
| |
| /** Scheduler to schedule against: nullptr to schedule against current |
| execution context */ |
| grpc_closure_scheduler* scheduler; |
| |
| /** Once queued, the result of the closure. Before then: scratch space */ |
| union { |
| grpc_error* error; |
| uintptr_t scratch; |
| } error_data; |
| |
| // extra tracing and debugging for grpc_closure. This incurs a decent amount of |
| // overhead per closure, so it must be enabled at compile time. |
| #ifndef NDEBUG |
| bool scheduled; |
| bool run; // true = run, false = scheduled |
| const char* file_created; |
| int line_created; |
| const char* file_initiated; |
| int line_initiated; |
| #endif |
| }; |
| |
| #ifndef NDEBUG |
| inline grpc_closure* grpc_closure_init(const char* file, int line, |
| grpc_closure* closure, |
| grpc_iomgr_cb_func cb, void* cb_arg, |
| grpc_closure_scheduler* scheduler) { |
| #else |
| inline grpc_closure* grpc_closure_init(grpc_closure* closure, |
| grpc_iomgr_cb_func cb, void* cb_arg, |
| grpc_closure_scheduler* scheduler) { |
| #endif |
| closure->cb = cb; |
| closure->cb_arg = cb_arg; |
| closure->scheduler = scheduler; |
| closure->error_data.error = GRPC_ERROR_NONE; |
| #ifndef NDEBUG |
| closure->scheduled = false; |
| closure->file_initiated = nullptr; |
| closure->line_initiated = 0; |
| closure->run = false; |
| closure->file_created = file; |
| closure->line_created = line; |
| #endif |
| return closure; |
| } |
| |
| /** Initializes \a closure with \a cb and \a cb_arg. Returns \a closure. */ |
| #ifndef NDEBUG |
| #define GRPC_CLOSURE_INIT(closure, cb, cb_arg, scheduler) \ |
| grpc_closure_init(__FILE__, __LINE__, closure, cb, cb_arg, scheduler) |
| #else |
| #define GRPC_CLOSURE_INIT(closure, cb, cb_arg, scheduler) \ |
| grpc_closure_init(closure, cb, cb_arg, scheduler) |
| #endif |
| |
| namespace closure_impl { |
| |
| typedef struct { |
| grpc_iomgr_cb_func cb; |
| void* cb_arg; |
| grpc_closure wrapper; |
| } wrapped_closure; |
| |
| inline void closure_wrapper(void* arg, grpc_error* error) { |
| wrapped_closure* wc = static_cast<wrapped_closure*>(arg); |
| grpc_iomgr_cb_func cb = wc->cb; |
| void* cb_arg = wc->cb_arg; |
| gpr_free(wc); |
| cb(cb_arg, error); |
| } |
| |
| } // namespace closure_impl |
| |
| #ifndef NDEBUG |
| inline grpc_closure* grpc_closure_create(const char* file, int line, |
| grpc_iomgr_cb_func cb, void* cb_arg, |
| grpc_closure_scheduler* scheduler) { |
| #else |
| inline grpc_closure* grpc_closure_create(grpc_iomgr_cb_func cb, void* cb_arg, |
| grpc_closure_scheduler* scheduler) { |
| #endif |
| closure_impl::wrapped_closure* wc = |
| static_cast<closure_impl::wrapped_closure*>(gpr_malloc(sizeof(*wc))); |
| wc->cb = cb; |
| wc->cb_arg = cb_arg; |
| #ifndef NDEBUG |
| grpc_closure_init(file, line, &wc->wrapper, closure_impl::closure_wrapper, wc, |
| scheduler); |
| #else |
| grpc_closure_init(&wc->wrapper, closure_impl::closure_wrapper, wc, scheduler); |
| #endif |
| return &wc->wrapper; |
| } |
| |
| /* Create a heap allocated closure: try to avoid except for very rare events */ |
| #ifndef NDEBUG |
| #define GRPC_CLOSURE_CREATE(cb, cb_arg, scheduler) \ |
| grpc_closure_create(__FILE__, __LINE__, cb, cb_arg, scheduler) |
| #else |
| #define GRPC_CLOSURE_CREATE(cb, cb_arg, scheduler) \ |
| grpc_closure_create(cb, cb_arg, scheduler) |
| #endif |
| |
| #define GRPC_CLOSURE_LIST_INIT \ |
| { nullptr, nullptr } |
| |
| inline void grpc_closure_list_init(grpc_closure_list* closure_list) { |
| closure_list->head = closure_list->tail = nullptr; |
| } |
| |
| /** add \a closure to the end of \a list |
| and set \a closure's result to \a error |
| Returns true if \a list becomes non-empty */ |
| inline bool grpc_closure_list_append(grpc_closure_list* closure_list, |
| grpc_closure* closure, grpc_error* error) { |
| if (closure == nullptr) { |
| GRPC_ERROR_UNREF(error); |
| return false; |
| } |
| closure->error_data.error = error; |
| closure->next_data.next = nullptr; |
| bool was_empty = (closure_list->head == nullptr); |
| if (was_empty) { |
| closure_list->head = closure; |
| } else { |
| closure_list->tail->next_data.next = closure; |
| } |
| closure_list->tail = closure; |
| return was_empty; |
| } |
| |
| /** force all success bits in \a list to false */ |
| inline void grpc_closure_list_fail_all(grpc_closure_list* list, |
| grpc_error* forced_failure) { |
| for (grpc_closure* c = list->head; c != nullptr; c = c->next_data.next) { |
| if (c->error_data.error == GRPC_ERROR_NONE) { |
| c->error_data.error = GRPC_ERROR_REF(forced_failure); |
| } |
| } |
| GRPC_ERROR_UNREF(forced_failure); |
| } |
| |
| /** append all closures from \a src to \a dst and empty \a src. */ |
| inline void grpc_closure_list_move(grpc_closure_list* src, |
| grpc_closure_list* dst) { |
| if (src->head == nullptr) { |
| return; |
| } |
| if (dst->head == nullptr) { |
| *dst = *src; |
| } else { |
| dst->tail->next_data.next = src->head; |
| dst->tail = src->tail; |
| } |
| src->head = src->tail = nullptr; |
| } |
| |
| /** return whether \a list is empty. */ |
| inline bool grpc_closure_list_empty(grpc_closure_list closure_list) { |
| return closure_list.head == nullptr; |
| } |
| |
| #ifndef NDEBUG |
| inline void grpc_closure_run(const char* file, int line, grpc_closure* c, |
| grpc_error* error) { |
| #else |
| inline void grpc_closure_run(grpc_closure* c, grpc_error* error) { |
| #endif |
| GPR_TIMER_SCOPE("grpc_closure_run", 0); |
| if (c != nullptr) { |
| #ifndef NDEBUG |
| c->file_initiated = file; |
| c->line_initiated = line; |
| c->run = true; |
| GPR_ASSERT(c->cb != nullptr); |
| #endif |
| c->scheduler->vtable->run(c, error); |
| } else { |
| GRPC_ERROR_UNREF(error); |
| } |
| } |
| |
| /** Run a closure directly. Caller ensures that no locks are being held above. |
| * Note that calling this at the end of a closure callback function itself is |
| * by definition safe. */ |
| #ifndef NDEBUG |
| #define GRPC_CLOSURE_RUN(closure, error) \ |
| grpc_closure_run(__FILE__, __LINE__, closure, error) |
| #else |
| #define GRPC_CLOSURE_RUN(closure, error) grpc_closure_run(closure, error) |
| #endif |
| |
| #ifndef NDEBUG |
| inline void grpc_closure_sched(const char* file, int line, grpc_closure* c, |
| grpc_error* error) { |
| #else |
| inline void grpc_closure_sched(grpc_closure* c, grpc_error* error) { |
| #endif |
| GPR_TIMER_SCOPE("grpc_closure_sched", 0); |
| if (c != nullptr) { |
| #ifndef NDEBUG |
| if (c->scheduled) { |
| gpr_log(GPR_ERROR, |
| "Closure already scheduled. (closure: %p, created: [%s:%d], " |
| "previously scheduled at: [%s: %d], newly scheduled at [%s: %d], " |
| "run?: %s", |
| c, c->file_created, c->line_created, c->file_initiated, |
| c->line_initiated, file, line, c->run ? "true" : "false"); |
| abort(); |
| } |
| c->scheduled = true; |
| c->file_initiated = file; |
| c->line_initiated = line; |
| c->run = false; |
| GPR_ASSERT(c->cb != nullptr); |
| #endif |
| c->scheduler->vtable->sched(c, error); |
| } else { |
| GRPC_ERROR_UNREF(error); |
| } |
| } |
| |
| /** Schedule a closure to be run. Does not need to be run from a safe point. */ |
| #ifndef NDEBUG |
| #define GRPC_CLOSURE_SCHED(closure, error) \ |
| grpc_closure_sched(__FILE__, __LINE__, closure, error) |
| #else |
| #define GRPC_CLOSURE_SCHED(closure, error) grpc_closure_sched(closure, error) |
| #endif |
| |
| #ifndef NDEBUG |
| inline void grpc_closure_list_sched(const char* file, int line, |
| grpc_closure_list* list) { |
| #else |
| inline void grpc_closure_list_sched(grpc_closure_list* list) { |
| #endif |
| grpc_closure* c = list->head; |
| while (c != nullptr) { |
| grpc_closure* next = c->next_data.next; |
| #ifndef NDEBUG |
| if (c->scheduled) { |
| gpr_log(GPR_ERROR, |
| "Closure already scheduled. (closure: %p, created: [%s:%d], " |
| "previously scheduled at: [%s: %d] run?: %s", |
| c, c->file_created, c->line_created, c->file_initiated, |
| c->line_initiated, c->run ? "true" : "false"); |
| abort(); |
| } |
| c->scheduled = true; |
| c->file_initiated = file; |
| c->line_initiated = line; |
| c->run = false; |
| GPR_ASSERT(c->cb != nullptr); |
| #endif |
| c->scheduler->vtable->sched(c, c->error_data.error); |
| c = next; |
| } |
| list->head = list->tail = nullptr; |
| } |
| |
| /** Schedule all closures in a list to be run. Does not need to be run from a |
| * safe point. */ |
| #ifndef NDEBUG |
| #define GRPC_CLOSURE_LIST_SCHED(closure_list) \ |
| grpc_closure_list_sched(__FILE__, __LINE__, closure_list) |
| #else |
| #define GRPC_CLOSURE_LIST_SCHED(closure_list) \ |
| grpc_closure_list_sched(closure_list) |
| #endif |
| |
| #endif /* GRPC_CORE_LIB_IOMGR_CLOSURE_H */ |