/*
* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
*
- * 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 <assert.h>
#include <string.h>
#include <unistd.h>
-#include <common/lttng-share.h>
-
-/*
- * 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 <common/common.h>
/*
* Maximum number of fd we can monitor.
*/
#ifdef HAVE_EPOLL
#include <sys/epoll.h>
+#include <stdio.h>
+#include <features.h>
+#include <common/compat/fcntl.h>
/* 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 */
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.
#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.
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
*/
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.
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)
/*
* 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
}
}
+/*
+ * 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 */
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
*/
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.
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
*/
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)
/*
* 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)
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.
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);
}
}
projects / lttng-tools.git / blobdiff