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Diffstat (limited to 'xorg-server/mi/mieq.c')
-rw-r--r--xorg-server/mi/mieq.c188
1 files changed, 152 insertions, 36 deletions
diff --git a/xorg-server/mi/mieq.c b/xorg-server/mi/mieq.c
index b75bde9de..093dba20f 100644
--- a/xorg-server/mi/mieq.c
+++ b/xorg-server/mi/mieq.c
@@ -59,7 +59,12 @@ in this Software without prior written authorization from The Open Group.
# include <X11/extensions/dpmsconst.h>
#endif
-#define QUEUE_SIZE 512
+/* Maximum size should be initial size multiplied by a power of 2 */
+#define QUEUE_INITIAL_SIZE 256
+#define QUEUE_RESERVED_SIZE 64
+#define QUEUE_MAXIMUM_SIZE 4096
+#define QUEUE_DROP_BACKTRACE_FREQUENCY 100
+#define QUEUE_DROP_BACKTRACE_MAX 10
#define EnqueueScreen(dev) dev->spriteInfo->sprite->pEnqueueScreen
#define DequeueScreen(dev) dev->spriteInfo->sprite->pDequeueScreen
@@ -74,7 +79,9 @@ typedef struct _EventQueue {
HWEventQueueType head, tail; /* long for SetInputCheck */
CARD32 lastEventTime; /* to avoid time running backwards */
int lastMotion; /* device ID if last event motion? */
- EventRec events[QUEUE_SIZE]; /* static allocation for signals */
+ EventRec *events; /* our queue as an array */
+ size_t nevents; /* the number of buckets in our queue */
+ size_t dropped; /* counter for number of consecutive dropped events */
mieqHandler handlers[128]; /* custom event handler */
} EventQueueRec, *EventQueuePtr;
@@ -99,25 +106,87 @@ static inline void wait_for_server_init(void) {
}
#endif
+static size_t
+mieqNumEnqueued(EventQueuePtr eventQueue) {
+ size_t n_enqueued = 0;
+ if (eventQueue->nevents) {
+ /* % is not well-defined with negative numbers... sigh */
+ n_enqueued = eventQueue->tail - eventQueue->head + eventQueue->nevents;
+ if (n_enqueued >= eventQueue->nevents)
+ n_enqueued -= eventQueue->nevents;
+ }
+ return n_enqueued;
+}
+
+/* Pre-condition: Called with miEventQueueMutex held */
+static Bool
+mieqGrowQueue(EventQueuePtr eventQueue, size_t new_nevents) {
+ size_t i, n_enqueued, first_hunk;
+ EventRec *new_events;
+
+ if (!eventQueue) {
+ ErrorF("[mi] mieqGrowQueue called with a NULL eventQueue\n");
+ return FALSE;
+ }
+
+ if (new_nevents <= eventQueue->nevents)
+ return FALSE;
+
+ new_events = calloc(new_nevents, sizeof(EventRec));
+ if (new_events == NULL) {
+ ErrorF("[mi] mieqGrowQueue memory allocation error.\n");
+ return FALSE;
+ }
+
+ n_enqueued = mieqNumEnqueued(eventQueue);
+
+ /* We block signals, so an mieqEnqueue triggered by SIGIO does not
+ * write to our queue as we are modifying it.
+ */
+ OsBlockSignals();
+
+ /* First copy the existing events */
+ first_hunk = eventQueue->nevents - eventQueue->head;
+ memcpy(new_events,
+ &eventQueue->events[eventQueue->head],
+ first_hunk * sizeof(EventRec));
+ memcpy(&new_events[first_hunk],
+ eventQueue->events,
+ eventQueue->head * sizeof(EventRec));
+
+ /* Initialize the new portion */
+ for (i = eventQueue->nevents; i < new_nevents; i++) {
+ InternalEvent* evlist = InitEventList(1);
+ if (!evlist) {
+ size_t j;
+ for (j = 0; j < i; j++)
+ FreeEventList(new_events[j].events, 1);
+ free(new_events);
+ OsReleaseSignals();
+ return FALSE;
+ }
+ new_events[i].events = evlist;
+ }
+
+ /* And update our record */
+ eventQueue->tail = n_enqueued;
+ eventQueue->head = 0;
+ eventQueue->nevents = new_nevents;
+ free(eventQueue->events);
+ eventQueue->events = new_events;
+
+ OsReleaseSignals();
+ return TRUE;
+}
+
Bool
mieqInit(void)
{
- int i;
-
- miEventQueue.head = miEventQueue.tail = 0;
+ memset(&miEventQueue, 0, sizeof(miEventQueue));
miEventQueue.lastEventTime = GetTimeInMillis ();
- miEventQueue.lastMotion = FALSE;
- for (i = 0; i < 128; i++)
- miEventQueue.handlers[i] = NULL;
- for (i = 0; i < QUEUE_SIZE; i++)
- {
- if (miEventQueue.events[i].events == NULL) {
- InternalEvent* evlist = InitEventList(1);
- if (!evlist)
- FatalError("Could not allocate event queue.\n");
- miEventQueue.events[i].events = evlist;
- }
- }
+
+ if(!mieqGrowQueue(&miEventQueue, QUEUE_INITIAL_SIZE))
+ FatalError("Could not allocate event queue.\n");
SetInputCheck(&miEventQueue.head, &miEventQueue.tail);
return TRUE;
@@ -127,13 +196,34 @@ void
mieqFini(void)
{
int i;
- for (i = 0; i < QUEUE_SIZE; i++)
+ for (i = 0; i < miEventQueue.nevents; i++)
{
if (miEventQueue.events[i].events != NULL) {
FreeEventList(miEventQueue.events[i].events, 1);
miEventQueue.events[i].events = NULL;
}
}
+ free(miEventQueue.events);
+}
+
+/* This function will determine if the given event is allowed to used the reserved
+ * queue space.
+ */
+static Bool
+mieqReservedCandidate(InternalEvent *e) {
+ switch(e->any.type) {
+ case ET_KeyRelease:
+ case ET_ButtonRelease:
+#if XFreeXDGA
+ case ET_DGAEvent:
+#endif
+ case ET_RawKeyRelease:
+ case ET_RawButtonRelease:
+ case ET_XQuartz:
+ return TRUE;
+ default:
+ return FALSE;
+ }
}
/*
@@ -151,6 +241,7 @@ mieqEnqueue(DeviceIntPtr pDev, InternalEvent *e)
int isMotion = 0;
int evlen;
Time time;
+ size_t n_enqueued;
#ifdef XQUARTZ
wait_for_server_init();
@@ -159,32 +250,40 @@ mieqEnqueue(DeviceIntPtr pDev, InternalEvent *e)
verify_internal_event(e);
+ n_enqueued = mieqNumEnqueued(&miEventQueue);
+
/* avoid merging events from different devices */
if (e->any.type == ET_Motion)
isMotion = pDev->id;
if (isMotion && isMotion == miEventQueue.lastMotion &&
oldtail != miEventQueue.head) {
- oldtail = (oldtail - 1) % QUEUE_SIZE;
- }
- else {
- static int stuck = 0;
+ oldtail = (oldtail - 1) % miEventQueue.nevents;
+ } else if ((n_enqueued + 1 == miEventQueue.nevents) ||
+ ((n_enqueued + 1 >= miEventQueue.nevents - QUEUE_RESERVED_SIZE) && !mieqReservedCandidate(e))) {
/* Toss events which come in late. Usually this means your server's
* stuck in an infinite loop somewhere, but SIGIO is still getting
- * handled. */
- if (((oldtail + 1) % QUEUE_SIZE) == miEventQueue.head) {
- if (!stuck) {
- ErrorF("[mi] EQ overflowing. The server is probably stuck "
- "in an infinite loop.\n");
- xorg_backtrace();
- stuck = 1;
+ * handled.
+ */
+ miEventQueue.dropped++;
+ if (miEventQueue.dropped == 1) {
+ ErrorF("[mi] EQ overflowing. Additional events will be discarded until existing events are processed.\n");
+ xorg_backtrace();
+ ErrorF("[mi] These backtraces from mieqEnqueue may point to a culprit higher up the stack.\n");
+ ErrorF("[mi] mieq is *NOT* the cause. It is a victim.\n");
+ } else if (miEventQueue.dropped % QUEUE_DROP_BACKTRACE_FREQUENCY == 0 &&
+ miEventQueue.dropped / QUEUE_DROP_BACKTRACE_FREQUENCY <= QUEUE_DROP_BACKTRACE_MAX) {
+ ErrorF("[mi] EQ overflow continuing. %lu events have been dropped.\n", miEventQueue.dropped);
+ if (miEventQueue.dropped / QUEUE_DROP_BACKTRACE_FREQUENCY == QUEUE_DROP_BACKTRACE_MAX) {
+ ErrorF("[mi] No further overflow reports will be reported until the clog is cleared.\n");
}
+ xorg_backtrace();
+ }
+
#ifdef XQUARTZ
- pthread_mutex_unlock(&miEventQueueMutex);
+ pthread_mutex_unlock(&miEventQueueMutex);
#endif
- return;
- }
- stuck = 0;
+ return;
}
evlen = e->any.length;
@@ -203,7 +302,7 @@ mieqEnqueue(DeviceIntPtr pDev, InternalEvent *e)
miEventQueue.events[oldtail].pDev = pDev;
miEventQueue.lastMotion = isMotion;
- miEventQueue.tail = (oldtail + 1) % QUEUE_SIZE;
+ miEventQueue.tail = (oldtail + 1) % miEventQueue.nevents;
#ifdef XQUARTZ
pthread_mutex_unlock(&miEventQueueMutex);
#endif
@@ -437,11 +536,28 @@ mieqProcessInputEvents(void)
static InternalEvent event;
DeviceIntPtr dev = NULL,
master = NULL;
+ size_t n_enqueued;
#ifdef XQUARTZ
pthread_mutex_lock(&miEventQueueMutex);
#endif
-
+
+ /* Grow our queue if we are reaching capacity: < 2 * QUEUE_RESERVED_SIZE remaining */
+ n_enqueued = mieqNumEnqueued(&miEventQueue);
+ if (n_enqueued >= (miEventQueue.nevents - (2 * QUEUE_RESERVED_SIZE)) &&
+ miEventQueue.nevents < QUEUE_MAXIMUM_SIZE) {
+ ErrorF("[mi] Increasing EQ size to %lu to prevent dropped events.\n", miEventQueue.nevents << 1);
+ if (!mieqGrowQueue(&miEventQueue, miEventQueue.nevents << 1)) {
+ ErrorF("[mi] Increasing the size of EQ failed.\n");
+ }
+ }
+
+ if (miEventQueue.dropped) {
+ ErrorF("[mi] EQ processing has resumed after %lu dropped events.\n", miEventQueue.dropped);
+ ErrorF("[mi] This may be caused my a misbehaving driver monopolizing the server's resources.\n");
+ miEventQueue.dropped = 0;
+ }
+
while (miEventQueue.head != miEventQueue.tail) {
e = &miEventQueue.events[miEventQueue.head];
@@ -449,7 +565,7 @@ mieqProcessInputEvents(void)
dev = e->pDev;
screen = e->pScreen;
- miEventQueue.head = (miEventQueue.head + 1) % QUEUE_SIZE;
+ miEventQueue.head = (miEventQueue.head + 1) % miEventQueue.nevents;
#ifdef XQUARTZ
pthread_mutex_unlock(&miEventQueueMutex);