diff options
Diffstat (limited to 'src/core/lib/iomgr/ev_posix.cc')
-rw-r--r-- | src/core/lib/iomgr/ev_posix.cc | 54 |
1 files changed, 45 insertions, 9 deletions
diff --git a/src/core/lib/iomgr/ev_posix.cc b/src/core/lib/iomgr/ev_posix.cc index 0e45fc42ca..b8fe017ce7 100644 --- a/src/core/lib/iomgr/ev_posix.cc +++ b/src/core/lib/iomgr/ev_posix.cc @@ -101,10 +101,28 @@ const grpc_event_engine_vtable* init_non_polling(bool explicit_request) { } } // namespace -static const event_engine_factory g_factories[] = { +#define ENGINE_HEAD_CUSTOM "head_custom" +#define ENGINE_TAIL_CUSTOM "tail_custom" + +// The global array of event-engine factories. Each entry is a pair with a name +// and an event-engine generator function (nullptr if there is no generator +// registered for this name). The middle entries are the engines predefined by +// open-source gRPC. The head entries represent an opportunity for specific +// high-priority custom pollers to be added by the initializer plugins of +// custom-built gRPC libraries. The tail entries represent the same, but for +// low-priority custom pollers. The actual poller selected is either the first +// available one in the list if no specific poller is requested, or the first +// specific poller that is requested by name in the GRPC_POLL_STRATEGY +// environment variable if that variable is set (which should be a +// comma-separated list of one or more event engine names) +static event_engine_factory g_factories[] = { + {ENGINE_HEAD_CUSTOM, nullptr}, {ENGINE_HEAD_CUSTOM, nullptr}, + {ENGINE_HEAD_CUSTOM, nullptr}, {ENGINE_HEAD_CUSTOM, nullptr}, {"epollex", grpc_init_epollex_linux}, {"epoll1", grpc_init_epoll1_linux}, {"epollsig", grpc_init_epollsig_linux}, {"poll", grpc_init_poll_posix}, {"poll-cv", grpc_init_poll_cv_posix}, {"none", init_non_polling}, + {ENGINE_TAIL_CUSTOM, nullptr}, {ENGINE_TAIL_CUSTOM, nullptr}, + {ENGINE_TAIL_CUSTOM, nullptr}, {ENGINE_TAIL_CUSTOM, nullptr}, }; static void add(const char* beg, const char* end, char*** ss, size_t* ns) { @@ -138,7 +156,7 @@ static bool is(const char* want, const char* have) { static void try_engine(const char* engine) { for (size_t i = 0; i < GPR_ARRAY_SIZE(g_factories); i++) { - if (is(engine, g_factories[i].name)) { + if (g_factories[i].factory != nullptr && is(engine, g_factories[i].name)) { if ((g_event_engine = g_factories[i].factory( 0 == strcmp(engine, g_factories[i].name)))) { g_poll_strategy_name = g_factories[i].name; @@ -149,14 +167,32 @@ static void try_engine(const char* engine) { } } -/* This should be used for testing purposes ONLY */ -void grpc_set_event_engine_test_only( - const grpc_event_engine_vtable* ev_engine) { - g_event_engine = ev_engine; -} +/* Call this before calling grpc_event_engine_init() */ +void grpc_register_event_engine_factory(const char* name, + event_engine_factory_fn factory, + bool add_at_head) { + const char* custom_match = + add_at_head ? ENGINE_HEAD_CUSTOM : ENGINE_TAIL_CUSTOM; + + // Overwrite an existing registration if already registered + for (size_t i = 0; i < GPR_ARRAY_SIZE(g_factories); i++) { + if (0 == strcmp(name, g_factories[i].name)) { + g_factories[i].factory = factory; + return; + } + } + + // Otherwise fill in an available custom slot + for (size_t i = 0; i < GPR_ARRAY_SIZE(g_factories); i++) { + if (0 == strcmp(g_factories[i].name, custom_match)) { + g_factories[i].name = name; + g_factories[i].factory = factory; + return; + } + } -const grpc_event_engine_vtable* grpc_get_event_engine_test_only() { - return g_event_engine; + // Otherwise fail + GPR_ASSERT(false); } /* Call this only after calling grpc_event_engine_init() */ |