X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fcompat%2Fpoll.h;h=fde54ddb91331c46a28ce75c590b060d338ef845;hp=a7766400d95adcc5a4b8ed9fb5bb4ce7d0bd21b3;hb=2a85be8e0e679da996b48252b1d9aebb9bb29126;hpb=0ba98ebc83bf874d34c8c84b164a6ad803e9de75 diff --git a/src/common/compat/poll.h b/src/common/compat/poll.h index a7766400d..fde54ddb9 100644 --- a/src/common/compat/poll.h +++ b/src/common/compat/poll.h @@ -1,33 +1,28 @@ /* * 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 -#include - -/* - * Value taken from the hard limit allowed by the kernel when using setrlimit - * with RLIMIT_NOFILE on an Intel i7 CPU and Linux 3.0.3. - */ -#define LTTNG_POLL_DEFAULT_SIZE 65535 +#include /* * Maximum number of fd we can monitor. @@ -56,9 +51,12 @@ static inline void __lttng_poll_free(void *events) */ #ifdef HAVE_EPOLL #include +#include +#include +#include /* See man epoll(7) for this define path */ -#define LTTNG_EPOLL_PROC_PATH "/proc/sys/fs/epoll/max_user_watches" +#define COMPAT_EPOLL_PROC_PATH "/proc/sys/fs/epoll/max_user_watches" enum { /* Polling variables compatibility for epoll */ @@ -75,17 +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. @@ -94,6 +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. @@ -101,7 +125,28 @@ struct compat_epoll_event { extern int compat_epoll_create(struct lttng_poll_event *events, int size, int flags); #define lttng_poll_create(events, size, flags) \ - compat_epoll_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 @@ -109,7 +154,7 @@ extern int compat_epoll_create(struct lttng_poll_event *events, */ extern int compat_epoll_wait(struct lttng_poll_event *events, int timeout); #define lttng_poll_wait(events, timeout) \ - compat_epoll_wait(events, timeout); + compat_epoll_wait(events, timeout) /* * Add a fd to the epoll set and resize the epoll_event structure if needed. @@ -117,21 +162,29 @@ extern int compat_epoll_wait(struct lttng_poll_event *events, int timeout); extern int compat_epoll_add(struct lttng_poll_event *events, int fd, uint32_t req_events); #define lttng_poll_add(events, fd, req_events) \ - compat_epoll_add(events, fd, req_events); + compat_epoll_add(events, fd, req_events) /* * Remove a fd from the epoll set. */ extern int compat_epoll_del(struct lttng_poll_event *events, int fd); #define lttng_poll_del(events, fd) \ - compat_epoll_del(events, fd); + compat_epoll_del(events, fd) + +/* + * Modify an fd's events in the epoll set. + */ +extern int compat_epoll_mod(struct lttng_poll_event *events, + int fd, uint32_t req_events); +#define lttng_poll_mod(events, fd, req_events) \ + compat_epoll_mod(events, fd, req_events) /* * Set up the poll set limits variable poll_max_size */ -extern void compat_epoll_set_max_size(void); -#define lttng_poll_set_max_size(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() /* * This function memset with zero the structure since it can be reused at each @@ -146,16 +199,37 @@ 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 */ @@ -185,36 +259,76 @@ enum { LPOLLRDBAND = POLLRDBAND, LPOLLWRNORM = POLLWRNORM, LPOLLWRBAND = POLLWRBAND, +#if __linux__ LPOLLMSG = POLLMSG, + LPOLLRDHUP = POLLRDHUP, +#elif (defined(__FreeBSD__) || defined(__CYGWIN__) || defined(__sun__) || defined(__APPLE__)) + LPOLLMSG = 0, + LPOLLRDHUP = 0, +#else +#error "Please add support for your OS." +#endif /* __linux__ */ LPOLLERR = POLLERR, LPOLLHUP = POLLHUP | POLLNVAL, - LPOLLRDHUP = POLLRDHUP, /* Close on exec feature does not exist for poll(2) */ 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'. */ extern int compat_poll_create(struct lttng_poll_event *events, int size); #define lttng_poll_create(events, size, flags) \ - compat_poll_create(events, size); + compat_poll_create(events, size) /* * Wait on poll(2) event with nb_fd registered to the lttng_poll_event data @@ -222,7 +336,7 @@ extern int compat_poll_create(struct lttng_poll_event *events, int size); */ extern int compat_poll_wait(struct lttng_poll_event *events, int timeout); #define lttng_poll_wait(events, timeout) \ - compat_poll_wait(events, timeout); + compat_poll_wait(events, timeout) /* * Add the fd to the pollfd structure. Resize if needed. @@ -230,7 +344,7 @@ extern int compat_poll_wait(struct lttng_poll_event *events, int timeout); extern int compat_poll_add(struct lttng_poll_event *events, int fd, uint32_t req_events); #define lttng_poll_add(events, fd, req_events) \ - compat_poll_add(events, fd, req_events); + compat_poll_add(events, fd, req_events) /* * Remove the fd from the pollfd. Memory allocation is done to recreate a new @@ -239,14 +353,22 @@ extern int compat_poll_add(struct lttng_poll_event *events, */ extern int compat_poll_del(struct lttng_poll_event *events, int fd); #define lttng_poll_del(events, fd) \ - compat_poll_del(events, fd); + compat_poll_del(events, fd) + +/* + * Modify an fd's events in the epoll set. + */ +extern int compat_poll_mod(struct lttng_poll_event *events, + int fd, uint32_t req_events); +#define lttng_poll_mod(events, fd, req_events) \ + compat_poll_mod(events, fd, req_events) /* * Set up the poll set limits variable poll_max_size */ -extern void compat_poll_set_max_size(void); -#define lttng_poll_set_max_size(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() /* * No need to reset a pollfd structure for poll(2) @@ -254,6 +376,14 @@ 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. @@ -261,7 +391,8 @@ 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); } }