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Fix bug in broadcast event trigger
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There was an issue with aliasing the number of event locations and the
requested event number that would cause a bug. A test needs to be
written to make sure it works anyhow.
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Dan Schatzberg authored and Dan Schatzberg committed May 16, 2012
1 parent f4a0e4d commit f2aaecb
Showing 1 changed file with 57 additions and 57 deletions.
114 changes: 57 additions & 57 deletions l0/lrt/ulnx/event.c
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Expand Up @@ -52,7 +52,7 @@ struct lrt_event_local_data {
};

//To be allocated at preinit, the array of local event data
static struct lrt_event_local_data *event_data;
static struct lrt_event_local_data *event_data;
static int num_cores = 0;

static const intptr_t PIPE_UDATA = -1;
Expand All @@ -79,7 +79,7 @@ lrt_event_loop(void)
do {
rc = epoll_wait(ldata->fd, &kev, 1, -1);
} while(rc == -1 && errno == EINTR);

if (rc == -1) {
perror("epoll");
LRT_Assert(0);
Expand All @@ -88,23 +88,23 @@ lrt_event_loop(void)
#endif

lrt_event_num ev;

if (
#if __APPLE__
kev.udata == (void *)PIPE_UDATA
kev.udata == (void *)PIPE_UDATA
#elif __linux__
kev.data.u64 == (uint64_t)PIPE_UDATA
kev.data.u64 == (uint64_t)PIPE_UDATA
#endif
) {
) {
//We received at least a byte on the pipe

//This is technically a blocking read, but I don't believe it
//matters because we only woke up because the pipe was ready
//to read and we are the only reader
ssize_t rc = read(ldata->pipefd_read, &ev, sizeof(ev));
LRT_Assert(rc == sizeof(ev));
//FIXME: check for errors

} else {
//IRQ occurred
#if __APPLE__
Expand All @@ -113,15 +113,15 @@ lrt_event_loop(void)
ev = (lrt_event_num)kev.data.u64;
#endif
}

struct lrt_event_descriptor *desc = &lrt_event_table[ev];
EBBId id = desc->id;
FuncNum fnum = desc->fnum;

//this infrastructure should be pulled out of this file
EBBRepRef ref = EBBId_DREF((EBBRepRef *)id);
(void)(*ref)[fnum](ref);

//an optimization here would be to keep reading from the pipe or checking
//other events before going back around the loop
}
Expand All @@ -146,7 +146,7 @@ lrt_event_init(void *myloc)
#else
lrt_event_myloc = (lrt_event_loc)(uintptr_t)myloc;
#endif

//get my local event data
struct lrt_event_local_data *ldata = &event_data[lrt_my_event_loc()];

Expand All @@ -166,7 +166,7 @@ lrt_event_init(void *myloc)

ldata->pipefd_read = pipes[0];
//this act publishes that this event location is ready to receive events
ldata->pipefd_write = pipes[1];
ldata->pipefd_write = pipes[1];

//add the pipe to the watched fd
#if __APPLE__
Expand All @@ -178,7 +178,7 @@ lrt_event_init(void *myloc)
//setup the read pipe event
struct kevent kev;
EV_SET(&kev, ldata->pipefd_read, EVFILT_READ,
EV_ADD, 0, 0, (void *)PIPE_UDATA);
EV_ADD, 0, 0, (void *)PIPE_UDATA);

//add it to the keventfd
kevent(ldata->fd, &kev, 1, NULL, 0, &timeout);
Expand All @@ -191,15 +191,15 @@ lrt_event_init(void *myloc)
epoll_ctl(ldata->fd, EPOLL_CTL_ADD, ldata->pipefd_read, &ev);
#endif

// we call the start routine to initialize
// we call the start routine to initialize
// mem and trans before falling into the loop
lrt_start();
lrt_event_loop();
}


/* get number of logical pics, i.e., cores */
lrt_event_loc
lrt_event_loc
lrt_num_event_loc()
{
return num_cores;
Expand All @@ -225,77 +225,77 @@ lrt_event_preinit(int cores)
//FIXME: initialize event table
}

void
void
lrt_event_bind_event(lrt_event_num num, EBBId handler, FuncNum fnum)
{
lrt_event_table[num].id = handler;
lrt_event_table[num].fnum = fnum;
}

void
lrt_event_trigger_event(lrt_event_num num,
enum lrt_event_loc_desc desc,
lrt_event_loc loc)
lrt_event_trigger_event(lrt_event_num num,
enum lrt_event_loc_desc desc,
lrt_event_loc loc)
{
int pipefd;

//TODO: Do something better for a local event

if (desc == LRT_EVENT_LOC_SINGLE) {
//protects from a race on startup
do {
pipefd = *(volatile int *)&event_data[loc].pipefd_write;
} while (pipefd == 0);

ssize_t rc = write(pipefd, &num, sizeof(num));
LRT_Assert(rc == sizeof(num));
//FIXME: check errors
} else if (desc == LRT_EVENT_LOC_ALL) {
lrt_event_loc num = lrt_num_event_loc();
for (lrt_event_loc i = 0; i < num; i++) {
lrt_event_loc num_ev = lrt_num_event_loc();
for (lrt_event_loc i = 0; i < num_ev; i++) {
//protects from a race on startup
do {
pipefd = *(volatile int *)&event_data[i].pipefd_write;
pipefd = *(volatile int *)&event_data[i].pipefd_write;
} while (pipefd == 0);
ssize_t rc = write(pipefd, &num, sizeof(num));

ssize_t rc = write(pipefd, &num, sizeof(num));
LRT_Assert(rc == sizeof(num));
}
}
//FIXME: check for errors
}

void
lrt_event_route_irq(struct IRQ_t *isrc, lrt_event_num num,
enum lrt_event_loc_desc desc, lrt_event_loc loc)
lrt_event_route_irq(struct IRQ_t *isrc, lrt_event_num num,
enum lrt_event_loc_desc desc, lrt_event_loc loc)
{
//No changes necessary if this conditional is true
if ((desc == LRT_EVENT_LOC_NONE && isrc->desc == LRT_EVENT_LOC_NONE) ||
(num == isrc->num &&
((desc == LRT_EVENT_LOC_ALL && isrc->desc == LRT_EVENT_LOC_ALL) ||
(desc == LRT_EVENT_LOC_SINGLE && isrc->desc == LRT_EVENT_LOC_SINGLE &&
loc == isrc->loc)))) {
(desc == LRT_EVENT_LOC_SINGLE && isrc->desc == LRT_EVENT_LOC_SINGLE &&
loc == isrc->loc)))) {
return;
}
#if __APPLE__
int numkevents = __builtin_popcount(isrc->flags);

struct kevent kevs_add[numkevents];
struct kevent kevs_remove[numkevents];

int i = numkevents;
if (isrc->flags & LRT_EVENT_IRQ_READ) {
EV_SET(&kevs_add[--i], isrc->fd, EVFILT_READ,
EV_ADD, 0, 0, (void *)(uintptr_t)num);
EV_ADD, 0, 0, (void *)(uintptr_t)num);
EV_SET(&kevs_remove[i], isrc->fd, EVFILT_READ,
EV_DELETE, 0, 0, (void *)(uintptr_t)num);
EV_DELETE, 0, 0, (void *)(uintptr_t)num);
}

if (isrc->flags & LRT_EVENT_IRQ_WRITE) {
EV_SET(&kevs_add[--i], isrc->fd, EVFILT_WRITE,
EV_ADD, 0, 0, (void *)(uintptr_t)num);
EV_ADD, 0, 0, (void *)(uintptr_t)num);
EV_SET(&kevs_remove[i], isrc->fd, EVFILT_WRITE,
EV_DELETE, 0, 0, (void *)(uintptr_t)num);
EV_DELETE, 0, 0, (void *)(uintptr_t)num);
}

struct timespec timeout = {
Expand All @@ -308,7 +308,7 @@ lrt_event_route_irq(struct IRQ_t *isrc, lrt_event_num num,
if (isrc->flags & LRT_EVENT_IRQ_READ) {
ev.events |= EPOLLIN;
}

if (isrc->flags & LRT_EVENT_IRQ_WRITE) {
ev.events |= EPOLLOUT;
}
Expand All @@ -323,38 +323,38 @@ lrt_event_route_irq(struct IRQ_t *isrc, lrt_event_num num,
// and not requested to be mapped or having a different event.
//In such a case, remove the event
if ((isrc->desc == LRT_EVENT_LOC_ALL ||
(isrc->desc == LRT_EVENT_LOC_SINGLE && isrc->loc == i)) &&
!(num == isrc->num &&
(desc == LRT_EVENT_LOC_ALL ||
(desc == LRT_EVENT_LOC_SINGLE && loc == i)))) {
(isrc->desc == LRT_EVENT_LOC_SINGLE && isrc->loc == i)) &&
!(num == isrc->num &&
(desc == LRT_EVENT_LOC_ALL ||
(desc == LRT_EVENT_LOC_SINGLE && loc == i)))) {
#if __APPLE__
kevent(ldata->fd, kevs_remove, numkevents, NULL, 0, &timeout);
kevent(ldata->fd, kevs_remove, numkevents, NULL, 0, &timeout);
#elif __linux__
epoll_ctl(ldata->fd, EPOLL_CTL_DEL, isrc->fd, NULL);
#endif
epoll_ctl(ldata->fd, EPOLL_CTL_DEL, isrc->fd, NULL);
#endif
}
//This checks if the irq is requested to be mapped in on core i
// and not already mapped or having a different event
//In such a case, add the event
if ((desc == LRT_EVENT_LOC_ALL ||
(desc == LRT_EVENT_LOC_SINGLE && loc == i)) &&
!(num == isrc->num &&
(isrc->desc == LRT_EVENT_LOC_ALL ||
(isrc->desc == LRT_EVENT_LOC_SINGLE && isrc->loc == i)))) {
(desc == LRT_EVENT_LOC_SINGLE && loc == i)) &&
!(num == isrc->num &&
(isrc->desc == LRT_EVENT_LOC_ALL ||
(isrc->desc == LRT_EVENT_LOC_SINGLE && isrc->loc == i)))) {
#if __APPLE__
kevent(ldata->fd, kevs_add, numkevents, NULL, 0, &timeout);
kevent(ldata->fd, kevs_add, numkevents, NULL, 0, &timeout);
#elif __linux__
epoll_ctl(ldata->fd, EPOLL_CTL_ADD, isrc->fd, &ev);
#endif
epoll_ctl(ldata->fd, EPOLL_CTL_ADD, isrc->fd, &ev);
#endif
}
}
} else {
//Checks if the irq is currently mapped and either is on a different
// event or is not mapped to the same event, then removes
if (isrc->desc == LRT_EVENT_LOC_SINGLE &&
!(num == isrc->num &&
desc == LRT_EVENT_LOC_SINGLE &&
isrc->loc == loc)) {
!(num == isrc->num &&
desc == LRT_EVENT_LOC_SINGLE &&
isrc->loc == loc)) {
struct lrt_event_local_data *ldata = &event_data[isrc->loc];
#if __APPLE__
kevent(ldata->fd, kevs_remove, numkevents, NULL, 0, &timeout);
Expand All @@ -365,9 +365,9 @@ lrt_event_route_irq(struct IRQ_t *isrc, lrt_event_num num,
//Checks if the request is to map it and either is on a different event
// or not the same location
if (desc == LRT_EVENT_LOC_SINGLE &&
!(num == isrc->num &&
isrc->desc == LRT_EVENT_LOC_SINGLE &&
isrc->loc == loc)) {
!(num == isrc->num &&
isrc->desc == LRT_EVENT_LOC_SINGLE &&
isrc->loc == loc)) {
struct lrt_event_local_data *ldata = &event_data[loc];
#if __APPLE__
kevent(ldata->fd, kevs_add, numkevents, NULL, 0, &timeout);
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