Revert "Revert "Upgrade to 2.1.8-stable (2017-01-22)." and "Probably Mac build fix?""
This reverts commit 83a0c9c65a60a92d3ea5542596b3ba56db492c37.
Bug: 64543673
Test: make checkbuild
Test: Manual tombstoned test
Change-Id: I84bb128d1dec433195f2cbdbf70236ba17fa9955
diff --git a/epoll.c b/epoll.c
index 4c5c3da..bf730b2 100644
--- a/epoll.c
+++ b/epoll.c
@@ -25,11 +25,14 @@
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "event2/event-config.h"
+#include "evconfig-private.h"
+
+#ifdef EVENT__HAVE_EPOLL
#include <stdint.h>
#include <sys/types.h>
#include <sys/resource.h>
-#ifdef _EVENT_HAVE_SYS_TIME_H
+#ifdef EVENT__HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#include <sys/queue.h>
@@ -41,9 +44,12 @@
#include <string.h>
#include <unistd.h>
#include <errno.h>
-#ifdef _EVENT_HAVE_FCNTL_H
+#ifdef EVENT__HAVE_FCNTL_H
#include <fcntl.h>
#endif
+#ifdef EVENT__HAVE_SYS_TIMERFD_H
+#include <sys/timerfd.h>
+#endif
#include "event-internal.h"
#include "evsignal-internal.h"
@@ -52,11 +58,38 @@
#include "log-internal.h"
#include "evmap-internal.h"
#include "changelist-internal.h"
+#include "time-internal.h"
+
+/* Since Linux 2.6.17, epoll is able to report about peer half-closed connection
+ using special EPOLLRDHUP flag on a read event.
+*/
+#if !defined(EPOLLRDHUP)
+#define EPOLLRDHUP 0
+#define EARLY_CLOSE_IF_HAVE_RDHUP 0
+#else
+#define EARLY_CLOSE_IF_HAVE_RDHUP EV_FEATURE_EARLY_CLOSE
+#endif
+
+#include "epolltable-internal.h"
+
+#if defined(EVENT__HAVE_SYS_TIMERFD_H) && \
+ defined(EVENT__HAVE_TIMERFD_CREATE) && \
+ defined(HAVE_POSIX_MONOTONIC) && defined(TFD_NONBLOCK) && \
+ defined(TFD_CLOEXEC)
+/* Note that we only use timerfd if TFD_NONBLOCK and TFD_CLOEXEC are available
+ and working. This means that we can't support it on 2.6.25 (where timerfd
+ was introduced) or 2.6.26, since 2.6.27 introduced those flags.
+ */
+#define USING_TIMERFD
+#endif
struct epollop {
struct epoll_event *events;
int nevents;
int epfd;
+#ifdef USING_TIMERFD
+ int timerfd;
+#endif
};
static void *epoll_init(struct event_base *);
@@ -66,12 +99,12 @@
static const struct eventop epollops_changelist = {
"epoll (with changelist)",
epoll_init,
- event_changelist_add,
- event_changelist_del,
+ event_changelist_add_,
+ event_changelist_del_,
epoll_dispatch,
epoll_dealloc,
1, /* need reinit */
- EV_FEATURE_ET|EV_FEATURE_O1,
+ EV_FEATURE_ET|EV_FEATURE_O1| EARLY_CLOSE_IF_HAVE_RDHUP,
EVENT_CHANGELIST_FDINFO_SIZE
};
@@ -89,7 +122,7 @@
epoll_dispatch,
epoll_dealloc,
1, /* need reinit */
- EV_FEATURE_ET|EV_FEATURE_O1,
+ EV_FEATURE_ET|EV_FEATURE_O1|EV_FEATURE_EARLY_CLOSE,
0
};
@@ -107,19 +140,24 @@
static void *
epoll_init(struct event_base *base)
{
- int epfd;
+ int epfd = -1;
struct epollop *epollop;
- /* Initialize the kernel queue. (The size field is ignored since
- * 2.6.8.) */
- if ((epfd = epoll_create(32000)) == -1) {
- if (errno != ENOSYS)
- event_warn("epoll_create");
- return (NULL);
+#ifdef EVENT__HAVE_EPOLL_CREATE1
+ /* First, try the shiny new epoll_create1 interface, if we have it. */
+ epfd = epoll_create1(EPOLL_CLOEXEC);
+#endif
+ if (epfd == -1) {
+ /* Initialize the kernel queue using the old interface. (The
+ size field is ignored since 2.6.8.) */
+ if ((epfd = epoll_create(32000)) == -1) {
+ if (errno != ENOSYS)
+ event_warn("epoll_create");
+ return (NULL);
+ }
+ evutil_make_socket_closeonexec(epfd);
}
- evutil_make_socket_closeonexec(epfd);
-
if (!(epollop = mm_calloc(1, sizeof(struct epollop)))) {
close(epfd);
return (NULL);
@@ -138,10 +176,48 @@
if ((base->flags & EVENT_BASE_FLAG_EPOLL_USE_CHANGELIST) != 0 ||
((base->flags & EVENT_BASE_FLAG_IGNORE_ENV) == 0 &&
- evutil_getenv("EVENT_EPOLL_USE_CHANGELIST") != NULL))
- base->evsel = &epollops_changelist;
+ evutil_getenv_("EVENT_EPOLL_USE_CHANGELIST") != NULL)) {
- evsig_init(base);
+ base->evsel = &epollops_changelist;
+ }
+
+#ifdef USING_TIMERFD
+ /*
+ The epoll interface ordinarily gives us one-millisecond precision,
+ so on Linux it makes perfect sense to use the CLOCK_MONOTONIC_COARSE
+ timer. But when the user has set the new PRECISE_TIMER flag for an
+ event_base, we can try to use timerfd to give them finer granularity.
+ */
+ if ((base->flags & EVENT_BASE_FLAG_PRECISE_TIMER) &&
+ base->monotonic_timer.monotonic_clock == CLOCK_MONOTONIC) {
+ int fd;
+ fd = epollop->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC);
+ if (epollop->timerfd >= 0) {
+ struct epoll_event epev;
+ memset(&epev, 0, sizeof(epev));
+ epev.data.fd = epollop->timerfd;
+ epev.events = EPOLLIN;
+ if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, fd, &epev) < 0) {
+ event_warn("epoll_ctl(timerfd)");
+ close(fd);
+ epollop->timerfd = -1;
+ }
+ } else {
+ if (errno != EINVAL && errno != ENOSYS) {
+ /* These errors probably mean that we were
+ * compiled with timerfd/TFD_* support, but
+ * we're running on a kernel that lacks those.
+ */
+ event_warn("timerfd_create");
+ }
+ epollop->timerfd = -1;
+ }
+ } else {
+ epollop->timerfd = -1;
+ }
+#endif
+
+ evsig_init_(base);
return (epollop);
}
@@ -170,6 +246,23 @@
"???";
}
+#define PRINT_CHANGES(op, events, ch, status) \
+ "Epoll %s(%d) on fd %d " status ". " \
+ "Old events were %d; " \
+ "read change was %d (%s); " \
+ "write change was %d (%s); " \
+ "close change was %d (%s)", \
+ epoll_op_to_string(op), \
+ events, \
+ ch->fd, \
+ ch->old_events, \
+ ch->read_change, \
+ change_to_string(ch->read_change), \
+ ch->write_change, \
+ change_to_string(ch->write_change), \
+ ch->close_change, \
+ change_to_string(ch->close_change)
+
static int
epoll_apply_one_change(struct event_base *base,
struct epollop *epollop,
@@ -177,156 +270,86 @@
{
struct epoll_event epev;
int op, events = 0;
+ int idx;
- if (1) {
- /* The logic here is a little tricky. If we had no events set
- on the fd before, we need to set op="ADD" and set
- events=the events we want to add. If we had any events set
- on the fd before, and we want any events to remain on the
- fd, we need to say op="MOD" and set events=the events we
- want to remain. But if we want to delete the last event,
- we say op="DEL" and set events=the remaining events. What
- fun!
- */
+ idx = EPOLL_OP_TABLE_INDEX(ch);
+ op = epoll_op_table[idx].op;
+ events = epoll_op_table[idx].events;
- /* TODO: Turn this into a switch or a table lookup. */
-
- if ((ch->read_change & EV_CHANGE_ADD) ||
- (ch->write_change & EV_CHANGE_ADD)) {
- /* If we are adding anything at all, we'll want to do
- * either an ADD or a MOD. */
- events = 0;
- op = EPOLL_CTL_ADD;
- if (ch->read_change & EV_CHANGE_ADD) {
- events |= EPOLLIN;
- } else if (ch->read_change & EV_CHANGE_DEL) {
- ;
- } else if (ch->old_events & EV_READ) {
- events |= EPOLLIN;
- }
- if (ch->write_change & EV_CHANGE_ADD) {
- events |= EPOLLOUT;
- } else if (ch->write_change & EV_CHANGE_DEL) {
- ;
- } else if (ch->old_events & EV_WRITE) {
- events |= EPOLLOUT;
- }
- if ((ch->read_change|ch->write_change) & EV_ET)
- events |= EPOLLET;
-
- if (ch->old_events) {
- /* If MOD fails, we retry as an ADD, and if
- * ADD fails we will retry as a MOD. So the
- * only hard part here is to guess which one
- * will work. As a heuristic, we'll try
- * MOD first if we think there were old
- * events and ADD if we think there were none.
- *
- * We can be wrong about the MOD if the file
- * has in fact been closed and re-opened.
- *
- * We can be wrong about the ADD if the
- * the fd has been re-created with a dup()
- * of the same file that it was before.
- */
- op = EPOLL_CTL_MOD;
- }
- } else if ((ch->read_change & EV_CHANGE_DEL) ||
- (ch->write_change & EV_CHANGE_DEL)) {
- /* If we're deleting anything, we'll want to do a MOD
- * or a DEL. */
- op = EPOLL_CTL_DEL;
-
- if (ch->read_change & EV_CHANGE_DEL) {
- if (ch->write_change & EV_CHANGE_DEL) {
- events = EPOLLIN|EPOLLOUT;
- } else if (ch->old_events & EV_WRITE) {
- events = EPOLLOUT;
- op = EPOLL_CTL_MOD;
- } else {
- events = EPOLLIN;
- }
- } else if (ch->write_change & EV_CHANGE_DEL) {
- if (ch->old_events & EV_READ) {
- events = EPOLLIN;
- op = EPOLL_CTL_MOD;
- } else {
- events = EPOLLOUT;
- }
- }
- }
-
- if (!events)
- return 0;
-
- memset(&epev, 0, sizeof(epev));
- epev.data.fd = ch->fd;
- epev.events = events;
- if (epoll_ctl(epollop->epfd, op, ch->fd, &epev) == -1) {
- if (op == EPOLL_CTL_MOD && errno == ENOENT) {
- /* If a MOD operation fails with ENOENT, the
- * fd was probably closed and re-opened. We
- * should retry the operation as an ADD.
- */
- if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, ch->fd, &epev) == -1) {
- event_warn("Epoll MOD(%d) on %d retried as ADD; that failed too",
- (int)epev.events, ch->fd);
- return -1;
- } else {
- event_debug(("Epoll MOD(%d) on %d retried as ADD; succeeded.",
- (int)epev.events,
- ch->fd));
- }
- } else if (op == EPOLL_CTL_ADD && errno == EEXIST) {
- /* If an ADD operation fails with EEXIST,
- * either the operation was redundant (as with a
- * precautionary add), or we ran into a fun
- * kernel bug where using dup*() to duplicate the
- * same file into the same fd gives you the same epitem
- * rather than a fresh one. For the second case,
- * we must retry with MOD. */
- if (epoll_ctl(epollop->epfd, EPOLL_CTL_MOD, ch->fd, &epev) == -1) {
- event_warn("Epoll ADD(%d) on %d retried as MOD; that failed too",
- (int)epev.events, ch->fd);
- return -1;
- } else {
- event_debug(("Epoll ADD(%d) on %d retried as MOD; succeeded.",
- (int)epev.events,
- ch->fd));
- }
- } else if (op == EPOLL_CTL_DEL &&
- (errno == ENOENT || errno == EBADF ||
- errno == EPERM)) {
- /* If a delete fails with one of these errors,
- * that's fine too: we closed the fd before we
- * got around to calling epoll_dispatch. */
- event_debug(("Epoll DEL(%d) on fd %d gave %s: DEL was unnecessary.",
- (int)epev.events,
- ch->fd,
- strerror(errno)));
- } else {
- event_warn("Epoll %s(%d) on fd %d failed. Old events were %d; read change was %d (%s); write change was %d (%s)",
- epoll_op_to_string(op),
- (int)epev.events,
- ch->fd,
- ch->old_events,
- ch->read_change,
- change_to_string(ch->read_change),
- ch->write_change,
- change_to_string(ch->write_change));
- return -1;
- }
- } else {
- event_debug(("Epoll %s(%d) on fd %d okay. [old events were %d; read change was %d; write change was %d]",
- epoll_op_to_string(op),
- (int)epev.events,
- (int)ch->fd,
- ch->old_events,
- ch->read_change,
- ch->write_change));
- }
+ if (!events) {
+ EVUTIL_ASSERT(op == 0);
+ return 0;
}
- return 0;
+
+ if ((ch->read_change|ch->write_change) & EV_CHANGE_ET)
+ events |= EPOLLET;
+
+ memset(&epev, 0, sizeof(epev));
+ epev.data.fd = ch->fd;
+ epev.events = events;
+ if (epoll_ctl(epollop->epfd, op, ch->fd, &epev) == 0) {
+ event_debug((PRINT_CHANGES(op, epev.events, ch, "okay")));
+ return 0;
+ }
+
+ switch (op) {
+ case EPOLL_CTL_MOD:
+ if (errno == ENOENT) {
+ /* If a MOD operation fails with ENOENT, the
+ * fd was probably closed and re-opened. We
+ * should retry the operation as an ADD.
+ */
+ if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, ch->fd, &epev) == -1) {
+ event_warn("Epoll MOD(%d) on %d retried as ADD; that failed too",
+ (int)epev.events, ch->fd);
+ return -1;
+ } else {
+ event_debug(("Epoll MOD(%d) on %d retried as ADD; succeeded.",
+ (int)epev.events,
+ ch->fd));
+ return 0;
+ }
+ }
+ break;
+ case EPOLL_CTL_ADD:
+ if (errno == EEXIST) {
+ /* If an ADD operation fails with EEXIST,
+ * either the operation was redundant (as with a
+ * precautionary add), or we ran into a fun
+ * kernel bug where using dup*() to duplicate the
+ * same file into the same fd gives you the same epitem
+ * rather than a fresh one. For the second case,
+ * we must retry with MOD. */
+ if (epoll_ctl(epollop->epfd, EPOLL_CTL_MOD, ch->fd, &epev) == -1) {
+ event_warn("Epoll ADD(%d) on %d retried as MOD; that failed too",
+ (int)epev.events, ch->fd);
+ return -1;
+ } else {
+ event_debug(("Epoll ADD(%d) on %d retried as MOD; succeeded.",
+ (int)epev.events,
+ ch->fd));
+ return 0;
+ }
+ }
+ break;
+ case EPOLL_CTL_DEL:
+ if (errno == ENOENT || errno == EBADF || errno == EPERM) {
+ /* If a delete fails with one of these errors,
+ * that's fine too: we closed the fd before we
+ * got around to calling epoll_dispatch. */
+ event_debug(("Epoll DEL(%d) on fd %d gave %s: DEL was unnecessary.",
+ (int)epev.events,
+ ch->fd,
+ strerror(errno)));
+ return 0;
+ }
+ break;
+ default:
+ break;
+ }
+
+ event_warn(PRINT_CHANGES(op, epev.events, ch, "failed"));
+ return -1;
}
static int
@@ -355,13 +378,16 @@
struct event_change ch;
ch.fd = fd;
ch.old_events = old;
- ch.read_change = ch.write_change = 0;
+ ch.read_change = ch.write_change = ch.close_change = 0;
if (events & EV_WRITE)
ch.write_change = EV_CHANGE_ADD |
(events & EV_ET);
if (events & EV_READ)
ch.read_change = EV_CHANGE_ADD |
(events & EV_ET);
+ if (events & EV_CLOSED)
+ ch.close_change = EV_CHANGE_ADD |
+ (events & EV_ET);
return epoll_apply_one_change(base, base->evbase, &ch);
}
@@ -373,11 +399,13 @@
struct event_change ch;
ch.fd = fd;
ch.old_events = old;
- ch.read_change = ch.write_change = 0;
+ ch.read_change = ch.write_change = ch.close_change = 0;
if (events & EV_WRITE)
ch.write_change = EV_CHANGE_DEL;
if (events & EV_READ)
ch.read_change = EV_CHANGE_DEL;
+ if (events & EV_CLOSED)
+ ch.close_change = EV_CHANGE_DEL;
return epoll_apply_one_change(base, base->evbase, &ch);
}
@@ -390,8 +418,35 @@
int i, res;
long timeout = -1;
+#ifdef USING_TIMERFD
+ if (epollop->timerfd >= 0) {
+ struct itimerspec is;
+ is.it_interval.tv_sec = 0;
+ is.it_interval.tv_nsec = 0;
+ if (tv == NULL) {
+ /* No timeout; disarm the timer. */
+ is.it_value.tv_sec = 0;
+ is.it_value.tv_nsec = 0;
+ } else {
+ if (tv->tv_sec == 0 && tv->tv_usec == 0) {
+ /* we need to exit immediately; timerfd can't
+ * do that. */
+ timeout = 0;
+ }
+ is.it_value.tv_sec = tv->tv_sec;
+ is.it_value.tv_nsec = tv->tv_usec * 1000;
+ }
+ /* TODO: we could avoid unnecessary syscalls here by only
+ calling timerfd_settime when the top timeout changes, or
+ when we're called with a different timeval.
+ */
+ if (timerfd_settime(epollop->timerfd, 0, &is, NULL) < 0) {
+ event_warn("timerfd_settime");
+ }
+ } else
+#endif
if (tv != NULL) {
- timeout = evutil_tv_to_msec(tv);
+ timeout = evutil_tv_to_msec_(tv);
if (timeout < 0 || timeout > MAX_EPOLL_TIMEOUT_MSEC) {
/* Linux kernels can wait forever if the timeout is
* too big; see comment on MAX_EPOLL_TIMEOUT_MSEC. */
@@ -400,7 +455,7 @@
}
epoll_apply_changes(base);
- event_changelist_remove_all(&base->changelist, base);
+ event_changelist_remove_all_(&base->changelist, base);
EVBASE_RELEASE_LOCK(base, th_base_lock);
@@ -423,6 +478,10 @@
for (i = 0; i < res; i++) {
int what = events[i].events;
short ev = 0;
+#ifdef USING_TIMERFD
+ if (events[i].data.fd == epollop->timerfd)
+ continue;
+#endif
if (what & (EPOLLHUP|EPOLLERR)) {
ev = EV_READ | EV_WRITE;
@@ -431,12 +490,14 @@
ev |= EV_READ;
if (what & EPOLLOUT)
ev |= EV_WRITE;
+ if (what & EPOLLRDHUP)
+ ev |= EV_CLOSED;
}
if (!ev)
continue;
- evmap_io_active(base, events[i].data.fd, ev | EV_ET);
+ evmap_io_active_(base, events[i].data.fd, ev | EV_ET);
}
if (res == epollop->nevents && epollop->nevents < MAX_NEVENT) {
@@ -462,12 +523,18 @@
{
struct epollop *epollop = base->evbase;
- evsig_dealloc(base);
+ evsig_dealloc_(base);
if (epollop->events)
mm_free(epollop->events);
if (epollop->epfd >= 0)
close(epollop->epfd);
+#ifdef USING_TIMERFD
+ if (epollop->timerfd >= 0)
+ close(epollop->timerfd);
+#endif
memset(epollop, 0, sizeof(struct epollop));
mm_free(epollop);
}
+
+#endif /* EVENT__HAVE_EPOLL */
