| /* |
| * FD polling functions for generic select() |
| * |
| * Copyright 2000-2014 Willy Tarreau <w@1wt.eu> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| */ |
| |
| #include <unistd.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| |
| #include <common/compat.h> |
| #include <common/config.h> |
| #include <common/ticks.h> |
| #include <common/time.h> |
| |
| #include <types/global.h> |
| |
| #include <proto/fd.h> |
| |
| |
| /* private data */ |
| static fd_set *fd_evts[2]; |
| static THREAD_LOCAL fd_set *tmp_evts[2]; |
| |
| /* Immediately remove the entry upon close() */ |
| REGPRM1 static void __fd_clo(int fd) |
| { |
| SPIN_LOCK(POLL_LOCK, &poll_lock); |
| FD_CLR(fd, fd_evts[DIR_RD]); |
| FD_CLR(fd, fd_evts[DIR_WR]); |
| SPIN_UNLOCK(POLL_LOCK, &poll_lock); |
| } |
| |
| /* |
| * Select() poller |
| */ |
| REGPRM2 static void _do_poll(struct poller *p, int exp) |
| { |
| int status; |
| int fd, i; |
| struct timeval delta; |
| int delta_ms; |
| int fds; |
| int updt_idx, en, eo; |
| char count; |
| int readnotnull, writenotnull; |
| |
| /* first, scan the update list to find changes */ |
| for (updt_idx = 0; updt_idx < fd_nbupdt; updt_idx++) { |
| fd = fd_updt[updt_idx]; |
| |
| if (!fdtab[fd].owner) |
| continue; |
| |
| SPIN_LOCK(FD_LOCK, &fdtab[fd].lock); |
| fdtab[fd].updated = 0; |
| fdtab[fd].new = 0; |
| |
| eo = fdtab[fd].state; |
| en = fd_compute_new_polled_status(eo); |
| fdtab[fd].state = en; |
| SPIN_UNLOCK(FD_LOCK, &fdtab[fd].lock); |
| |
| if ((eo ^ en) & FD_EV_POLLED_RW) { |
| /* poll status changed, update the lists */ |
| SPIN_LOCK(POLL_LOCK, &poll_lock); |
| if ((eo & ~en) & FD_EV_POLLED_R) |
| FD_CLR(fd, fd_evts[DIR_RD]); |
| else if ((en & ~eo) & FD_EV_POLLED_R) |
| FD_SET(fd, fd_evts[DIR_RD]); |
| |
| if ((eo & ~en) & FD_EV_POLLED_W) |
| FD_CLR(fd, fd_evts[DIR_WR]); |
| else if ((en & ~eo) & FD_EV_POLLED_W) |
| FD_SET(fd, fd_evts[DIR_WR]); |
| SPIN_UNLOCK(POLL_LOCK, &poll_lock); |
| } |
| } |
| fd_nbupdt = 0; |
| |
| /* let's restore fdset state */ |
| readnotnull = 0; writenotnull = 0; |
| for (i = 0; i < (maxfd + FD_SETSIZE - 1)/(8*sizeof(int)); i++) { |
| readnotnull |= (*(((int*)tmp_evts[DIR_RD])+i) = *(((int*)fd_evts[DIR_RD])+i)) != 0; |
| writenotnull |= (*(((int*)tmp_evts[DIR_WR])+i) = *(((int*)fd_evts[DIR_WR])+i)) != 0; |
| } |
| |
| #if 0 |
| /* just a verification code, needs to be removed for performance */ |
| for (i=0; i<maxfd; i++) { |
| if (FD_ISSET(i, tmp_evts[DIR_RD]) != FD_ISSET(i, fd_evts[DIR_RD])) |
| abort(); |
| if (FD_ISSET(i, tmp_evts[DIR_WR]) != FD_ISSET(i, fd_evts[DIR_WR])) |
| abort(); |
| } |
| #endif |
| |
| delta_ms = 0; |
| delta.tv_sec = 0; |
| delta.tv_usec = 0; |
| |
| if (!exp) { |
| delta_ms = MAX_DELAY_MS; |
| delta.tv_sec = (MAX_DELAY_MS / 1000); |
| delta.tv_usec = (MAX_DELAY_MS % 1000) * 1000; |
| } |
| else if (!tick_is_expired(exp, now_ms)) { |
| delta_ms = TICKS_TO_MS(tick_remain(now_ms, exp)) + SCHEDULER_RESOLUTION; |
| if (delta_ms > MAX_DELAY_MS) |
| delta_ms = MAX_DELAY_MS; |
| delta.tv_sec = (delta_ms / 1000); |
| delta.tv_usec = (delta_ms % 1000) * 1000; |
| } |
| |
| gettimeofday(&before_poll, NULL); |
| status = select(maxfd, |
| readnotnull ? tmp_evts[DIR_RD] : NULL, |
| writenotnull ? tmp_evts[DIR_WR] : NULL, |
| NULL, |
| &delta); |
| |
| tv_update_date(delta_ms, status); |
| measure_idle(); |
| |
| if (status <= 0) |
| return; |
| |
| for (fds = 0; (fds * BITS_PER_INT) < maxfd; fds++) { |
| if ((((int *)(tmp_evts[DIR_RD]))[fds] | ((int *)(tmp_evts[DIR_WR]))[fds]) == 0) |
| continue; |
| |
| for (count = BITS_PER_INT, fd = fds * BITS_PER_INT; count && fd < maxfd; count--, fd++) { |
| unsigned int n = 0; |
| |
| /* if we specify read first, the accepts and zero reads will be |
| * seen first. Moreover, system buffers will be flushed faster. |
| */ |
| if (!fdtab[fd].owner) |
| continue; |
| |
| if (FD_ISSET(fd, tmp_evts[DIR_RD])) |
| n |= FD_POLL_IN; |
| |
| if (FD_ISSET(fd, tmp_evts[DIR_WR])) |
| n |= FD_POLL_OUT; |
| |
| fd_update_events(fd, n); |
| } |
| } |
| } |
| |
| static int init_select_per_thread() |
| { |
| int fd_set_bytes; |
| |
| fd_set_bytes = sizeof(fd_set) * (global.maxsock + FD_SETSIZE - 1) / FD_SETSIZE; |
| if ((tmp_evts[DIR_RD] = (fd_set *)calloc(1, fd_set_bytes)) == NULL) |
| goto fail; |
| if ((tmp_evts[DIR_WR] = (fd_set *)calloc(1, fd_set_bytes)) == NULL) |
| goto fail; |
| return 1; |
| fail: |
| free(tmp_evts[DIR_RD]); |
| free(tmp_evts[DIR_WR]); |
| return 0; |
| } |
| |
| static void deinit_select_per_thread() |
| { |
| free(tmp_evts[DIR_WR]); |
| free(tmp_evts[DIR_RD]); |
| } |
| |
| /* |
| * Initialization of the select() poller. |
| * Returns 0 in case of failure, non-zero in case of success. If it fails, it |
| * disables the poller by setting its pref to 0. |
| */ |
| REGPRM1 static int _do_init(struct poller *p) |
| { |
| __label__ fail_swevt, fail_srevt, fail_revt; |
| int fd_set_bytes; |
| |
| p->private = NULL; |
| |
| if (global.maxsock > FD_SETSIZE) |
| goto fail_revt; |
| |
| fd_set_bytes = sizeof(fd_set) * (global.maxsock + FD_SETSIZE - 1) / FD_SETSIZE; |
| if (global.nbthread > 1) { |
| hap_register_per_thread_init(init_select_per_thread); |
| hap_register_per_thread_deinit(deinit_select_per_thread); |
| } |
| else if (!init_select_per_thread()) |
| goto fail_revt; |
| |
| if ((fd_evts[DIR_RD] = (fd_set *)calloc(1, fd_set_bytes)) == NULL) |
| goto fail_srevt; |
| if ((fd_evts[DIR_WR] = (fd_set *)calloc(1, fd_set_bytes)) == NULL) |
| goto fail_swevt; |
| |
| return 1; |
| |
| fail_swevt: |
| free(fd_evts[DIR_RD]); |
| fail_srevt: |
| free(tmp_evts[DIR_WR]); |
| free(tmp_evts[DIR_RD]); |
| fail_revt: |
| p->pref = 0; |
| return 0; |
| } |
| |
| /* |
| * Termination of the select() poller. |
| * Memory is released and the poller is marked as unselectable. |
| */ |
| REGPRM1 static void _do_term(struct poller *p) |
| { |
| free(fd_evts[DIR_WR]); |
| free(fd_evts[DIR_RD]); |
| free(tmp_evts[DIR_WR]); |
| free(tmp_evts[DIR_RD]); |
| p->private = NULL; |
| p->pref = 0; |
| } |
| |
| /* |
| * Check that the poller works. |
| * Returns 1 if OK, otherwise 0. |
| */ |
| REGPRM1 static int _do_test(struct poller *p) |
| { |
| if (global.maxsock > FD_SETSIZE) |
| return 0; |
| |
| return 1; |
| } |
| |
| /* |
| * It is a constructor, which means that it will automatically be called before |
| * main(). This is GCC-specific but it works at least since 2.95. |
| * Special care must be taken so that it does not need any uninitialized data. |
| */ |
| __attribute__((constructor)) |
| static void _do_register(void) |
| { |
| struct poller *p; |
| |
| if (nbpollers >= MAX_POLLERS) |
| return; |
| p = &pollers[nbpollers++]; |
| |
| p->name = "select"; |
| p->pref = 150; |
| p->flags = 0; |
| p->private = NULL; |
| |
| p->clo = __fd_clo; |
| p->test = _do_test; |
| p->init = _do_init; |
| p->term = _do_term; |
| p->poll = _do_poll; |
| } |
| |
| |
| /* |
| * Local variables: |
| * c-indent-level: 8 |
| * c-basic-offset: 8 |
| * End: |
| */ |