MAJOR: ev_select: make the poller support speculative events

The poller was updated to support speculative events. We'll need this
to fully support SSL.

diff --git a/src/ev_select.c b/src/ev_select.c
index 100bc575659592e73beb8977097b8ad059b62875..a4fe3d7398334f2925ba8928ffcf72399b3b81c8 100644 (file)
--- a/src/ev_select.c
+++ b/src/ev_select.c
@@ -1,7 +1,7 @@
 /*
  * FD polling functions for generic select()
  *
- * Copyright 2000-2008 Willy Tarreau <w@1wt.eu>
+ * Copyright 2000-2012 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
@@ -29,28 +29,8 @@
 static fd_set *fd_evts[2];
 static fd_set *tmp_evts[2];
 
-
-/*
- * Benchmarks performed on a Pentium-M notebook show that using functions
- * instead of the usual macros improve the FD_* performance by about 80%,
- * and that marking them regparm(2) adds another 20%.
- */
-REGPRM2 static int __fd_is_set(const int fd, int dir)
-{
-       return FD_ISSET(fd, fd_evts[dir]);
-}
-
-REGPRM2 static void __fd_set(const int fd, int dir)
-{
-       FD_SET(fd, fd_evts[dir]);
-}
-
-REGPRM2 static void __fd_clr(const int fd, int dir)
-{
-       FD_CLR(fd, fd_evts[dir]);
-}
-
-REGPRM1 static void __fd_rem(int fd)
+/* Immediately remove the entry upon close() */
+REGPRM1 static void __fd_clo(int fd)
 {
        FD_CLR(fd, fd_evts[DIR_RD]);
        FD_CLR(fd, fd_evts[DIR_WR]);
@@ -67,13 +47,53 @@ REGPRM2 static void _do_poll(struct poller *p, int exp)
        int delta_ms;
        int readnotnull, writenotnull;
        int fds;
+       int updt_idx, en, eo;
        char count;
                
+       /* first, scan the update list to find changes */
+       for (updt_idx = 0; updt_idx < fd_nbupdt; updt_idx++) {
+               fd = fd_updt[updt_idx];
+               en = fdtab[fd].spec_e & 15;  /* new events */
+               eo = fdtab[fd].spec_e >> 4;  /* previous events */
+
+               if (fdtab[fd].owner && (eo ^ en)) {
+                       if ((eo ^ en) & FD_EV_POLLED_RW) {
+                               /* poll status changed, update the lists */
+                               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]);
+                       }
+
+                       fdtab[fd].spec_e = (en << 4) + en;  /* save new events */
+
+                       if (!(en & FD_EV_ACTIVE_RW)) {
+                               /* This fd doesn't use any active entry anymore, we can
+                                * kill its entry.
+                                */
+                               release_spec_entry(fd);
+                       }
+                       else if ((en & ~eo) & FD_EV_ACTIVE_RW) {
+                               /* we need a new spec entry now */
+                               alloc_spec_entry(fd);
+                       }
+
+               }
+               fdtab[fd].updated = 0;
+               fdtab[fd].new = 0;
+       }
+       fd_nbupdt = 0;
+
        delta_ms      = 0;
        delta.tv_sec  = 0;
        delta.tv_usec = 0;
 
-       if (!run_queue && !signal_queue_len) {
+       if (!fd_nbspec && !run_queue && !signal_queue_len) {
                if (!exp) {
                        delta_ms      = MAX_DELAY_MS;
                        delta.tv_sec  = (MAX_DELAY_MS / 1000);
@@ -136,8 +156,19 @@ REGPRM2 static void _do_poll(struct poller *p, int exp)
                        if (FD_ISSET(fd, tmp_evts[DIR_WR]))
                                fdtab[fd].ev |= FD_POLL_OUT;
 
-                       if (fdtab[fd].iocb && fdtab[fd].owner && fdtab[fd].ev)
+                       if (fdtab[fd].iocb && fdtab[fd].owner && fdtab[fd].ev) {
+                               /* Mark the events as speculative before processing
+                                * them so that if nothing can be done we don't need
+                                * to poll again.
+                                */
+                               if (fdtab[fd].ev & (FD_POLL_IN|FD_POLL_HUP|FD_POLL_ERR))
+                                       fd_ev_set(fd, DIR_RD);
+
+                               if (fdtab[fd].ev & (FD_POLL_OUT|FD_POLL_ERR))
+                                       fd_ev_set(fd, DIR_WR);
+
                                fdtab[fd].iocb(fd);
+                       }
                }
        }
 }
@@ -225,11 +256,12 @@ static void _do_register(void)
        p->init = _do_init;
        p->term = _do_term;
        p->poll = _do_poll;
-       p->is_set = __fd_is_set;
-       p->set = __fd_set;
-       p->wai = __fd_set;
-       p->clr = __fd_clr;
-       p->clo = p->rem = __fd_rem;
+       p->is_set = NULL;
+       p->set = NULL;
+       p->wai = NULL;
+       p->clr = NULL;
+       p->rem = NULL;
+       p->clo = __fd_clo;
 }