X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fcompat%2Fpoll.h;h=77c46a1d08d60ac8bca806628f368fc46fc915c2;hp=bb046c3427af53f49a76997874a3d43b1808ba37;hb=a97dd6ce0d6f658c50b7cca73724fd8e1d5a36a1;hpb=b2c3836f9872dfe8c0328c03fa5a01efe0ed6017 diff --git a/src/common/compat/poll.h b/src/common/compat/poll.h index bb046c342..77c46a1d0 100644 --- a/src/common/compat/poll.h +++ b/src/common/compat/poll.h @@ -1,23 +1,24 @@ /* * Copyright (C) 2011 - David Goulet * - * 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; only version 2 of the License. + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2 only, + * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., 59 Temple - * Place - Suite 330, Boston, MA 02111-1307, USA. + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #ifndef _LTT_POLL_H #define _LTT_POLL_H +#include #include #include @@ -50,6 +51,9 @@ static inline void __lttng_poll_free(void *events) */ #ifdef HAVE_EPOLL #include +#include +#include +#include /* See man epoll(7) for this define path */ #define COMPAT_EPOLL_PROC_PATH "/proc/sys/fs/epoll/max_user_watches" @@ -69,17 +73,41 @@ enum { LPOLLNVAL = EPOLLHUP, LPOLLRDHUP = EPOLLRDHUP, /* Close on exec feature of epoll */ +#if defined(HAVE_EPOLL_CREATE1) && defined(EPOLL_CLOEXEC) LTTNG_CLOEXEC = EPOLL_CLOEXEC, +#else + /* + * EPOLL_CLOEXEC was added in glibc 2.8 (usually used in conjunction with + * epoll_create1(..)), but since neither EPOLL_CLOEXEC exists nor + * epoll_create1(..), we set it to FD_CLOEXEC so that we can pass it + * directly to fcntl(..) instead. + */ + LTTNG_CLOEXEC = FD_CLOEXEC, +#endif }; struct compat_epoll_event { int epfd; uint32_t nb_fd; /* Current number of fd in events */ - uint32_t events_size; /* Size of events array */ + uint32_t alloc_size; /* Size of events array */ + uint32_t init_size; /* Initial size of events array */ struct epoll_event *events; }; #define lttng_poll_event compat_epoll_event +static inline int __lttng_epoll_get_prev_fd(struct lttng_poll_event *events, + int index, uint32_t nb_fd) +{ + assert(events); + assert(index != nb_fd); + + if (index == 0 || nb_fd == 0) { + return -1; + } else { + return events->events[index - 1].data.fd; + } +} + /* * For the following calls, consider 'e' to be a lttng_poll_event pointer and i * being the index of the events array. @@ -88,6 +116,8 @@ struct compat_epoll_event { #define LTTNG_POLL_GETEV(e, i) LTTNG_REF(e)->events[i].events #define LTTNG_POLL_GETNB(e) LTTNG_REF(e)->nb_fd #define LTTNG_POLL_GETSZ(e) LTTNG_REF(e)->events_size +#define LTTNG_POLL_GET_PREV_FD(e, i, nb_fd) \ + __lttng_epoll_get_prev_fd(LTTNG_REF(e), i, nb_fd) /* * Create the epoll set. No memory allocation is done here. @@ -97,6 +127,27 @@ extern int compat_epoll_create(struct lttng_poll_event *events, #define lttng_poll_create(events, size, flags) \ compat_epoll_create(events, size, flags) +#if defined(HAVE_EPOLL_CREATE1) && defined(EPOLL_CLOEXEC) +static inline int compat_glibc_epoll_create(int size __attribute__((unused)), + int flags) +{ + return epoll_create1(flags); +} +#else +static inline int compat_glibc_epoll_create(int size, int flags) +{ + /* + * epoll_create1 was added in glibc 2.9, but unfortunatly reverting to + * epoll_create(..) also means that we lose the possibility to + * directly set the EPOLL_CLOEXEC, so try and do it anyway but through + * fcntl(..). + */ + int efd = epoll_create(size); + assert(fcntl(efd, F_SETFD, flags) != -1); + return efd; +} +#endif + /* * Wait on epoll set with the number of fd registered to the lttng_poll_event * data structure (events). @@ -123,7 +174,7 @@ extern int compat_epoll_del(struct lttng_poll_event *events, int fd); /* * Set up the poll set limits variable poll_max_size */ -extern void compat_epoll_set_max_size(void); +extern int compat_epoll_set_max_size(void); #define lttng_poll_set_max_size() \ compat_epoll_set_max_size() @@ -140,16 +191,37 @@ static inline void lttng_poll_reset(struct lttng_poll_event *events) } } +/* + * Initialize an already allocated poll event data structure. For epoll(), the + * epfd is set to -1 to indicate that it's not usable. + */ +static inline void lttng_poll_init(struct lttng_poll_event *events) +{ + memset(events, 0, sizeof(struct lttng_poll_event)); + /* Set fd to -1 so if clean before created, we don't close 0. */ + events->epfd = -1; +} + /* * Clean the events structure of a lttng_poll_event. It's the caller * responsability to free the lttng_poll_event memory. */ static inline void lttng_poll_clean(struct lttng_poll_event *events) { - if (events) { - close(events->epfd); - __lttng_poll_free((void *) events->events); + int ret; + + if (!events) { + return; + } + + if (events->epfd >= 0) { + ret = close(events->epfd); + if (ret) { + PERROR("close"); + } } + + __lttng_poll_free((void *) events->events); } #else /* HAVE_EPOLL */ @@ -182,7 +254,7 @@ enum { #if __linux__ LPOLLMSG = POLLMSG, LPOLLRDHUP = POLLRDHUP, -#elif defined(__FreeBSD__) +#elif (defined(__FreeBSD__) || defined(__CYGWIN__) || defined(__sun__) || defined(__APPLE__)) LPOLLMSG = 0, LPOLLRDHUP = 0, #else @@ -194,21 +266,54 @@ enum { LTTNG_CLOEXEC = 0xdead, }; -struct compat_poll_event { +struct compat_poll_event_array { uint32_t nb_fd; /* Current number of fd in events */ - uint32_t events_size; /* Size of events array */ + uint32_t alloc_size; /* Size of events array */ + /* Initial size of the pollset. We never shrink below that. */ + uint32_t init_size; struct pollfd *events; }; + +struct compat_poll_event { + /* + * Modified by the wait action. Updated using current fields if the + * need_update flag is set. + */ + struct compat_poll_event_array wait; + /* + * This is modified by add/del actions being the _current_ flow of + * execution before a poll wait is done. + */ + struct compat_poll_event_array current; + + /* Indicate if wait.events need to be updated from current. */ + int need_update:1; +}; #define lttng_poll_event compat_poll_event +static inline int __lttng_poll_get_prev_fd(struct lttng_poll_event *events, + int index, uint32_t nb_fd) +{ + assert(events); + assert(index != nb_fd); + + if (index == 0 || nb_fd == 0) { + return -1; + } else { + return events->current.events[index - 1].fd; + } +} + /* * For the following calls, consider 'e' to be a lttng_poll_event pointer and i * being the index of the events array. */ -#define LTTNG_POLL_GETFD(e, i) LTTNG_REF(e)->events[i].fd -#define LTTNG_POLL_GETEV(e, i) LTTNG_REF(e)->events[i].revents -#define LTTNG_POLL_GETNB(e) LTTNG_REF(e)->nb_fd -#define LTTNG_POLL_GETSZ(e) LTTNG_REF(e)->events_size +#define LTTNG_POLL_GETFD(e, i) LTTNG_REF(e)->wait.events[i].fd +#define LTTNG_POLL_GETEV(e, i) LTTNG_REF(e)->wait.events[i].revents +#define LTTNG_POLL_GETNB(e) LTTNG_REF(e)->wait.nb_fd +#define LTTNG_POLL_GETSZ(e) LTTNG_REF(e)->wait.events_size +#define LTTNG_POLL_GET_PREV_FD(e, i, nb_fd) \ + __lttng_poll_get_prev_fd(LTTNG_REF(e), i, nb_fd) /* * Create a pollfd structure of size 'size'. @@ -245,7 +350,7 @@ extern int compat_poll_del(struct lttng_poll_event *events, int fd); /* * Set up the poll set limits variable poll_max_size */ -extern void compat_poll_set_max_size(void); +extern int compat_poll_set_max_size(void); #define lttng_poll_set_max_size() \ compat_poll_set_max_size() @@ -255,6 +360,14 @@ extern void compat_poll_set_max_size(void); static inline void lttng_poll_reset(struct lttng_poll_event *events) {} +/* + * Initialize an already allocated poll event data structure. + */ +static inline void lttng_poll_init(struct lttng_poll_event *events) +{ + memset(events, 0, sizeof(struct lttng_poll_event)); +} + /* * Clean the events structure of a lttng_poll_event. It's the caller * responsability to free the lttng_poll_event memory. @@ -262,7 +375,8 @@ static inline void lttng_poll_reset(struct lttng_poll_event *events) static inline void lttng_poll_clean(struct lttng_poll_event *events) { if (events) { - __lttng_poll_free((void *) events->events); + __lttng_poll_free((void *) events->wait.events); + __lttng_poll_free((void *) events->current.events); } }