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Diffstat (limited to 'src/core/lib/iomgr/pollset_posix.h')
| -rw-r--r-- | src/core/lib/iomgr/pollset_posix.h | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/src/core/lib/iomgr/pollset_posix.h b/src/core/lib/iomgr/pollset_posix.h new file mode 100644 index 0000000000..7d8e9fc279 --- /dev/null +++ b/src/core/lib/iomgr/pollset_posix.h @@ -0,0 +1,153 @@ +/* + * + * Copyright 2015-2016, 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. + * + */ + +#ifndef GRPC_CORE_LIB_IOMGR_POLLSET_POSIX_H +#define GRPC_CORE_LIB_IOMGR_POLLSET_POSIX_H + +#include <poll.h> + +#include <grpc/support/sync.h> + +#include "src/core/lib/iomgr/exec_ctx.h" +#include "src/core/lib/iomgr/iomgr.h" +#include "src/core/lib/iomgr/pollset.h" +#include "src/core/lib/iomgr/wakeup_fd_posix.h" + +typedef struct grpc_pollset_vtable grpc_pollset_vtable; + +/* forward declare only in this file to avoid leaking impl details via + pollset.h; real users of grpc_fd should always include 'fd_posix.h' and not + use the struct tag */ +struct grpc_fd; + +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 { + /* pollsets under posix can mutate representation as fds are added and + removed. + For example, we may choose a poll() based implementation on linux for + few fds, and an epoll() based implementation for many fds */ + const grpc_pollset_vtable *vtable; + gpr_mu mu; + grpc_pollset_worker root_worker; + int in_flight_cbs; + int shutting_down; + int called_shutdown; + int kicked_without_pollers; + grpc_closure *shutdown_done; + grpc_closure_list idle_jobs; + union { + int fd; + void *ptr; + } data; + /* Local cache of eventfds for workers */ + grpc_cached_wakeup_fd *local_wakeup_cache; +}; + +struct grpc_pollset_vtable { + void (*add_fd)(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + struct grpc_fd *fd, int and_unlock_pollset); + void (*maybe_work_and_unlock)(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + grpc_pollset_worker *worker, + gpr_timespec deadline, gpr_timespec now); + void (*finish_shutdown)(grpc_pollset *pollset); + void (*destroy)(grpc_pollset *pollset); +}; + +/* Add an fd to a pollset */ +void grpc_pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset, + struct grpc_fd *fd); + +/* Returns the fd to listen on for kicks */ +int grpc_kick_read_fd(grpc_pollset *p); +/* Call after polling has been kicked to leave the kicked state */ +void grpc_kick_drain(grpc_pollset *p); + +/* 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 */ +int grpc_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 grpc_pollset_kick, with an extended set of flags (defined above) + -- mostly for fd_posix's use. */ +void grpc_pollset_kick_ext(grpc_pollset *p, + grpc_pollset_worker *specific_worker, + uint32_t flags); + +/* turn a pollset into a multipoller: platform specific */ +typedef void (*grpc_platform_become_multipoller_type)(grpc_exec_ctx *exec_ctx, + grpc_pollset *pollset, + struct grpc_fd **fds, + size_t fd_count); +extern grpc_platform_become_multipoller_type grpc_platform_become_multipoller; + +void grpc_poll_become_multipoller(grpc_exec_ctx *exec_ctx, + grpc_pollset *pollset, struct grpc_fd **fds, + size_t fd_count); + +/* Return 1 if the pollset has active threads in grpc_pollset_work (pollset must + * be locked) */ +int grpc_pollset_has_workers(grpc_pollset *pollset); + +void grpc_remove_fd_from_all_epoll_sets(int fd); + +/* override to allow tests to hook poll() usage */ +/* NOTE: Any changes to grpc_poll_function must take place when the gRPC + is certainly not doing any polling anywhere. + Otherwise, there might be a race between changing the variable and actually + doing a polling operation */ +typedef int (*grpc_poll_function_type)(struct pollfd *, nfds_t, int); +extern grpc_poll_function_type grpc_poll_function; +extern grpc_wakeup_fd grpc_global_wakeup_fd; + +#endif /* GRPC_CORE_LIB_IOMGR_POLLSET_POSIX_H */ |