From 6483ee77ed12f037d68a6adc690624fa1b508dc0 Mon Sep 17 00:00:00 2001

From: Daniel P. Berrange <berrange@redhat.com>

Date: Tue, 12 May 2009 16:43:04 +0000

Subject: [PATCH 2/2] Fix watch/timer event deletion

---

 qemud/event.c |  112 ++++++++++++++++++++++++++-------------------------------

 1 files changed, 51 insertions(+), 61 deletions(-)

diff --git a/qemud/event.c b/qemud/event.c

index 754f2b1..a57d967 100644

--- a/qemud/event.c

+++ b/qemud/event.c

@@ -313,7 +313,7 @@ static int virEventCalculateTimeout(int *timeout) {

     EVENT_DEBUG("Calculate expiry of %d timers", eventLoop.timeoutsCount);

     /* Figure out if we need a timeout */

     for (i = 0 ; i < eventLoop.timeoutsCount ; i++) {

-        if (eventLoop.timeouts[i].deleted || eventLoop.timeouts[i].frequency < 0)

+        if (eventLoop.timeouts[i].frequency < 0)

             continue;

         EVENT_DEBUG("Got a timeout scheduled for %llu", eventLoop.timeouts[i].expiresAt);

@@ -350,32 +350,26 @@ static int virEventCalculateTimeout(int *timeout) {

  * file handles. The caller must free the returned data struct

  * returns: the pollfd array, or NULL on error

  */

-static int virEventMakePollFDs(struct pollfd **retfds) {

+static struct pollfd *virEventMakePollFDs(void) {

     struct pollfd *fds;

-    int i, nfds = 0;

+    int i;

-    for (i = 0 ; i < eventLoop.handlesCount ; i++) {

-        if (eventLoop.handles[i].deleted)

-            continue;

-        nfds++;

-    }

-    *retfds = NULL;

     /* Setup the poll file handle data structs */

-    if (VIR_ALLOC_N(fds, nfds) < 0)

-        return -1;

+    if (VIR_ALLOC_N(fds, eventLoop.handlesCount) < 0)

+        return NULL;

-    for (i = 0, nfds = 0 ; i < eventLoop.handlesCount ; i++) {

-        if (eventLoop.handles[i].deleted)

-            continue;

-        fds[nfds].fd = eventLoop.handles[i].fd;

-        fds[nfds].events = eventLoop.handles[i].events;

-        fds[nfds].revents = 0;

+    for (i = 0 ; i < eventLoop.handlesCount ; i++) {

+        EVENT_DEBUG("Prepare n=%d w=%d, f=%d e=%d", i,

+                    eventLoop.handles[i].watch,

+                    eventLoop.handles[i].fd,

+                    eventLoop.handles[i].events);

+        fds[i].fd = eventLoop.handles[i].fd;

+        fds[i].events = eventLoop.handles[i].events;

+        fds[i].revents = 0;

         //EVENT_DEBUG("Wait for %d %d", eventLoop.handles[i].fd, eventLoop.handles[i].events);

-        nfds++;

     }

-    *retfds = fds;

-    return nfds;

+    return fds;

 }

@@ -435,26 +429,30 @@ static int virEventDispatchTimeouts(void) {

  * Returns 0 upon success, -1 if an error occurred

  */

 static int virEventDispatchHandles(int nfds, struct pollfd *fds) {

-    int i, n;

+    int i;

-    for (i = 0, n = 0 ; i < eventLoop.handlesCount && n < nfds ; i++) {

+    /* NB, use nfds not eventLoop.handlesCount, because new

+     * fds might be added on end of list, and they're not

+     * in the fds array we've got */

+    for (i = 0 ; i < nfds ; i++) {

         if (eventLoop.handles[i].deleted) {

-            EVENT_DEBUG("Skip deleted %d", eventLoop.handles[i].fd);

+            EVENT_DEBUG("Skip deleted n=%d w=%d f=%d", i,

+                        eventLoop.handles[i].watch, eventLoop.handles[i].fd);

             continue;

         }

-        if (fds[n].revents) {

+        if (fds[i].revents) {

             virEventHandleCallback cb = eventLoop.handles[i].cb;

             void *opaque = eventLoop.handles[i].opaque;

-            int hEvents = virPollEventToEventHandleType(fds[n].revents);

-            EVENT_DEBUG("Dispatch %d %d %p", fds[n].fd,

-                        fds[n].revents, eventLoop.handles[i].opaque);

+            int hEvents = virPollEventToEventHandleType(fds[i].revents);

+            EVENT_DEBUG("Dispatch n=%d f=%d w=%d e=%d %p", i,

+                        fds[i].fd, eventLoop.handles[i].watch,

+                        fds[i].revents, eventLoop.handles[i].opaque);

             virEventUnlock();

             (cb)(eventLoop.handles[i].watch,

-                 fds[n].fd, hEvents, opaque);

+                 fds[i].fd, hEvents, opaque);

             virEventLock();

         }

-        n++;

     }

     return 0;

@@ -545,22 +543,21 @@ static int virEventCleanupHandles(void) {

  * at least one file handle has an event, or a timer expires

  */

 int virEventRunOnce(void) {

-    struct pollfd *fds;

+    struct pollfd *fds = NULL;

     int ret, timeout, nfds;

     virEventLock();

     eventLoop.running = 1;

     eventLoop.leader = pthread_self();

-    if ((nfds = virEventMakePollFDs(&fds)) < 0) {

-        virEventUnlock();

-        return -1;

-    }

-    if (virEventCalculateTimeout(&timeout) < 0) {

-        VIR_FREE(fds);

-        virEventUnlock();

-        return -1;

-    }

+    if (virEventCleanupTimeouts() < 0 ||

+        virEventCleanupHandles() < 0)

+        goto error;

+

+    if (!(fds = virEventMakePollFDs()) ||

+        virEventCalculateTimeout(&timeout) < 0)

+        goto error;

+    nfds = eventLoop.handlesCount;

     virEventUnlock();

@@ -572,38 +569,31 @@ int virEventRunOnce(void) {

         if (errno == EINTR) {

             goto retry;

         }

-        VIR_FREE(fds);

-        return -1;

+        goto error_unlocked;

     }

     virEventLock();

-    if (virEventDispatchTimeouts() < 0) {

-        VIR_FREE(fds);

-        virEventUnlock();

-        return -1;

-    }

+    if (virEventDispatchTimeouts() < 0)

+        goto error;

     if (ret > 0 &&

-        virEventDispatchHandles(nfds, fds) < 0) {

-        VIR_FREE(fds);

-        virEventUnlock();

-        return -1;

-    }

-    VIR_FREE(fds);

-

-    if (virEventCleanupTimeouts() < 0) {

-        virEventUnlock();

-        return -1;

-    }

+        virEventDispatchHandles(nfds, fds) < 0)

+        goto error;

-    if (virEventCleanupHandles() < 0) {

-        virEventUnlock();

-        return -1;

-    }

+    if (virEventCleanupTimeouts() < 0 ||

+        virEventCleanupHandles() < 0)

+        goto error;

     eventLoop.running = 0;

     virEventUnlock();

+    VIR_FREE(fds);

     return 0;

+

+error:

+    virEventUnlock();

+error_unlocked:

+    VIR_FREE(fds);

+    return -1;

 }

 static void virEventHandleWakeup(int watch ATTRIBUTE_UNUSED,

-- 

1.6.0.6