X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/9189fe94c14ef9e31142d1603a1979ea7e731a0a..6a6157abf9619875297ff1d16c1e5c63c526d4c1:/src/gras/Transport/rl_transport.c diff --git a/src/gras/Transport/rl_transport.c b/src/gras/Transport/rl_transport.c index ecbcd065f5..d1db33016b 100644 --- a/src/gras/Transport/rl_transport.c +++ b/src/gras/Transport/rl_transport.c @@ -1,8 +1,7 @@ -/* $Id$ */ - /* rl_transport - RL specific functions for transport */ -/* Copyright (c) 2004 Martin Quinson. All rights reserved. */ +/* Copyright (c) 2004, 2005, 2006, 2007, 2009, 2010. The SimGrid Team. + * All rights reserved. */ /* This program is free software; you can redistribute it and/or modify it * under the terms of the license (GNU LGPL) which comes with this package. */ @@ -10,8 +9,10 @@ #include "xbt/ex.h" #include "portable.h" #include "gras/Transport/transport_private.h" -XBT_LOG_EXTERNAL_CATEGORY(transport); -XBT_LOG_DEFAULT_CATEGORY(transport); +XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(gras_trp); + +/* check transport_private.h for an explanation of this variable */ +gras_socket_t _gras_lastly_selected_socket = NULL; /** * gras_trp_select: @@ -20,12 +21,14 @@ XBT_LOG_DEFAULT_CATEGORY(transport); * * if timeout<0, we ought to implement the adaptative timeout (FIXME) * - * if timeout=0, do not wait for new message, only handle the ones already there. * * if timeout>0 and no message there, wait at most that amount of time before giving up. */ -gras_socket_t gras_trp_select(double timeout) { - xbt_dynar_t sockets= gras_socketset_get(); +gras_socket_t gras_trp_select(double timeout) +{ + xbt_dynar_t sockets = + ((gras_trp_procdata_t) + gras_libdata_by_id(gras_trp_libdata_id))->sockets; int done = -1; double wakeup = gras_os_time() + timeout; double now = 0; @@ -33,69 +36,90 @@ gras_socket_t gras_trp_select(double timeout) { /* static int nextToService = 0; */ struct timeval tout, *p_tout; - int max_fds=0; /* first arg of select: number of existing sockets */ + int max_fds = 0; /* first arg of select: number of existing sockets */ /* but accept() of winsock returns sockets bigger than the limit, so don't bother with this tiny optimisation on BillWare */ fd_set FDS; - int ready; /* return of select: number of socket ready to be serviced */ - int fd_setsize; /* FD_SETSIZE not always defined. Get this portably */ - - gras_socket_t sock_iter; /* iterating over all sockets */ - int cursor; /* iterating over all sockets */ + int ready; /* return of select: number of socket ready to be serviced */ + static int fd_setsize = -1; /* FD_SETSIZE not always defined. Get this portably */ + + gras_socket_t sock_iter; /* iterating over all sockets */ + unsigned int cursor; /* iterating over all sockets */ + + /* Check whether there is more data to read from the socket we selected last time. + This can happen with tcp buffered sockets since we try to get as much data as we can for them */ + if (_gras_lastly_selected_socket + && _gras_lastly_selected_socket->moredata) { + XBT_VERB + ("Returning _gras_lastly_selected_socket since there is more data on it"); + return _gras_lastly_selected_socket; + } - - /* Compute FD_SETSIZE */ + /* Compute FD_SETSIZE on need */ + if (fd_setsize < 0) { #ifdef HAVE_SYSCONF - fd_setsize = sysconf( _SC_OPEN_MAX ); + fd_setsize = sysconf(_SC_OPEN_MAX); #else -# ifdef HAVE_GETDTABLESIZE - fd_setsize = getdtablesize(); +# ifdef HAVE_GETDTABLESIZE + fd_setsize = getdtablesize(); # else - fd_setsize = FD_SETSIZE; -# endif /* !USE_SYSCONF */ + fd_setsize = FD_SETSIZE; +# endif /* !USE_SYSCONF */ #endif + } while (done == -1) { - if (timeout > 0) { /* did we timeout already? */ + if (timeout > 0) { /* did we timeout already? */ now = gras_os_time(); + XBT_DEBUG("wakeup=%f now=%f", wakeup, now); if (now == -1 || now >= wakeup) { - done = 0; /* didn't find anything */ - break; + /* didn't find anything; no need to update _gras_lastly_selected_socket since its moredata is 0 (or we would have returned it directly) */ + THROW1(timeout_error, 0, + "Timeout (%f) elapsed with selecting for incomming connexions", + timeout); } } /* construct the set of socket to ear from */ FD_ZERO(&FDS); max_fds = -1; - xbt_dynar_foreach(sockets,cursor,sock_iter) { + xbt_dynar_foreach(sockets, cursor, sock_iter) { + if (!sock_iter->valid) + continue; + if (sock_iter->incoming) { - DEBUG1("Considering socket %d for select",sock_iter->sd); + XBT_DEBUG("Considering socket %d for select", sock_iter->sd); #ifndef HAVE_WINSOCK_H - if (max_fds < sock_iter->sd) - max_fds = sock_iter->sd; + if (max_fds < sock_iter->sd) + max_fds = sock_iter->sd; +#else + max_fds = 0; + #endif - FD_SET(sock_iter->sd, &FDS); + FD_SET(sock_iter->sd, &FDS); } else { - DEBUG1("Not considering socket %d for select",sock_iter->sd); + XBT_DEBUG("Not considering socket %d for select", sock_iter->sd); } } + if (max_fds == -1) { - if (timeout > 0) { - DEBUG1("No socket to select onto. Sleep %f sec instead.",timeout); - gras_os_sleep(timeout); - THROW1(timeout_error,0,"No socket to select onto. Sleep %f sec instead",timeout); - } else { - DEBUG0("No socket to select onto. Return directly."); - THROW0(timeout_error,0, "No socket to select onto. Return directly."); - } + if (timeout > 0) { + XBT_DEBUG("No socket to select onto. Sleep %f sec instead.", timeout); + gras_os_sleep(timeout); + THROW1(timeout_error, 0, + "No socket to select onto. Sleep %f sec instead", timeout); + } else { + XBT_DEBUG("No socket to select onto. Return directly."); + THROW0(timeout_error, 0, + "No socket to select onto. Return directly."); + } } - #ifndef HAVE_WINSOCK_H /* we cannot have more than FD_SETSIZE sockets ... but with WINSOCK which returns sockets higher than the limit (killing this optim) */ if (++max_fds > fd_setsize && fd_setsize > 0) { - WARN1("too many open sockets (%d).",max_fds); + XBT_WARN("too many open sockets (%d).", max_fds); done = 0; break; } @@ -103,10 +127,12 @@ gras_socket_t gras_trp_select(double timeout) { max_fds = fd_setsize; #endif - if (timeout > 0) { + tout.tv_sec = tout.tv_usec = 0; + if (timeout > 0) { /* set the timeout */ - tout.tv_sec = (unsigned long)((wakeup - now)/1000000); - tout.tv_usec = (unsigned long)(wakeup - now) % 1000000; + tout.tv_sec = (unsigned long) (wakeup - now); + tout.tv_usec = + ((wakeup - now) - ((unsigned long) (wakeup - now))) * 1000000; p_tout = &tout; } else if (timeout == 0) { /* polling only */ @@ -115,89 +141,105 @@ gras_socket_t gras_trp_select(double timeout) { p_tout = &tout; /* we just do one loop around */ done = 0; - } else { + } else { /* no timeout: good luck! */ p_tout = NULL; } - - DEBUG1("Selecting over %d socket(s)", max_fds-1); + + XBT_DEBUG("Selecting over %d socket(s); timeout=%f", max_fds - 1, + timeout); ready = select(max_fds, &FDS, NULL, NULL, p_tout); + XBT_DEBUG("select returned %d", ready); if (ready == -1) { switch (errno) { - case EINTR: /* a signal we don't care about occured. we don't care */ - /* if we cared, we would have set an handler */ - continue; - case EINVAL: /* invalid value */ - THROW3(system_error,EINVAL,"invalid select: nb fds: %d, timeout: %d.%d", - max_fds, (int)tout.tv_sec,(int) tout.tv_usec); - case ENOMEM: - xbt_assert0(0,"Malloc error during the select"); + case EINTR: /* a signal we don't care about occured. we don't care */ + /* if we cared, we would have set an handler */ + continue; + case EINVAL: /* invalid value */ + THROW3(system_error, EINVAL, + "invalid select: nb fds: %d, timeout: %d.%d", max_fds, + (int) tout.tv_sec, (int) tout.tv_usec); + case ENOMEM: + xbt_die("Malloc error during the select"); default: - THROW2(system_error,errno,"Error during select: %s (%d)", - strerror(errno),errno); + THROW2(system_error, errno, "Error during select: %s (%d)", + strerror(errno), errno); } THROW_IMPOSSIBLE; } else if (ready == 0) { - continue; /* this was a timeout */ + continue; /* this was a timeout */ } - xbt_dynar_foreach(sockets,cursor,sock_iter) { - if(!FD_ISSET(sock_iter->sd, &FDS)) { /* this socket is not ready */ - continue; - } - - /* Got a socket to serve */ - ready--; - - if ( sock_iter->accepting - && sock_iter->plugin->socket_accept) { - /* not a socket but an ear. accept on it and serve next socket */ - gras_socket_t accepted=NULL; - - accepted = (sock_iter->plugin->socket_accept)(sock_iter); - DEBUG2("accepted=%p,&accepted=%p",accepted,&accepted); - accepted->meas = sock_iter->meas; - } else { -#if 0 - FIXME: this fails of files. quite logical - /* Make sure the socket is still alive by reading the first byte */ - char lookahead; - int recvd; - - recvd = recv(sock_iter->sd, &lookahead, 1, MSG_PEEK); - if (recvd < 0) { - WARN2("socket %d failed: %s", sock_iter->sd, strerror(errno)); - /* done with this socket */ - gras_socket_close(&sock_iter); - cursor--; - } else if (recvd == 0) { - /* Connection reset (=closed) by peer. */ - DEBUG1("Connection %d reset by peer", sock_iter->sd); - gras_socket_close(&sock_iter); - cursor--; - } else { -#endif - /* Got a suited socket ! */ - XBT_OUT; - return sock_iter; -#if 0 - } -#endif - } + xbt_dynar_foreach(sockets, cursor, sock_iter) { + if (!FD_ISSET(sock_iter->sd, &FDS)) { /* this socket is not ready */ + continue; + } + + /* Got a socket to serve */ + ready--; + + if (sock_iter->accepting && sock_iter->plugin->socket_accept) { + /* not a socket but an ear. accept on it and serve next socket */ + gras_socket_t accepted = NULL; + + /* release mutex before accept; it will change the sockets dynar, so we have to break the foreach asap */ + xbt_dynar_cursor_unlock(sockets); + accepted = (sock_iter->plugin->socket_accept) (sock_iter); + + XBT_DEBUG("accepted=%p,&accepted=%p", accepted, &accepted); + accepted->meas = sock_iter->meas; + break; - - /* if we're here, the socket we found wasn't really ready to be served */ - if (ready == 0) /* exausted all sockets given by select. Request new ones */ - break; + } else { + /* Make sure the socket is still alive by reading the first byte */ + int recvd; + + if (sock_iter->recvd) { + /* Socket wasn't used since last time! Don't bother checking whether it's still alive */ + recvd = 1; + } else { + recvd = read(sock_iter->sd, &sock_iter->recvd_val, 1); + } + + if (recvd < 0) { + XBT_WARN("socket %d failed: %s", sock_iter->sd, strerror(errno)); + /* done with this socket; remove it and break the foreach since it will change the dynar */ + xbt_dynar_cursor_unlock(sockets); + gras_socket_close(sock_iter); + break; + } else if (recvd == 0) { + /* Connection reset (=closed) by peer. */ + XBT_DEBUG("Connection %d reset by peer", sock_iter->sd); + sock_iter->valid = 0; /* don't close it. User may keep references to it */ + } else { + /* Got a suited socket ! */ + XBT_OUT(); + sock_iter->recvd = 1; + XBT_DEBUG("Filled little buffer (%c %x %d)", sock_iter->recvd_val, + sock_iter->recvd_val, recvd); + _gras_lastly_selected_socket = sock_iter; + /* break sync dynar iteration */ + xbt_dynar_cursor_unlock(sockets); + return sock_iter; + } + } + + /* if we're here, the socket we found wasn't really ready to be served */ + if (ready == 0) { /* exausted all sockets given by select. Request new ones */ + + xbt_dynar_cursor_unlock(sockets); + break; + } } } - XBT_OUT; - return NULL; + /* No socket found. Maybe we had timeout=0 and nothing to do */ + XBT_DEBUG("TIMEOUT"); + THROW0(timeout_error, 0, "Timeout"); } -void gras_trp_sg_setup(gras_trp_plugin_t plug) { - THROW0(mismatch_error,0,"No SG transport on live platforms"); +void gras_trp_sg_setup(gras_trp_plugin_t plug) +{ + THROW0(mismatch_error, 0, "No SG transport on live platforms"); } -