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CID1508860: double lock confusion #10443

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Merged
cmcfarlen merged 2 commits into from
Sep 19, 2023
Merged

CID1508860: double lock confusion #10443

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98a38b6
CID1508860: double lock confusion
cmcfarlen Sep 15, 2023
3bc5126
fix renames inside conditional code. Fix casts
cmcfarlen Sep 19, 2023
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24 changes: 12 additions & 12 deletions iocore/aio/AIO.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -77,8 +77,9 @@ AIOTestData::ink_aio_stats(int event, void *d)
ink_hrtime now = ink_get_hrtime();
double time_msec = (double)(now - start) / (double)HRTIME_MSECOND;
int i = (aio_reqs[0] == nullptr) ? 1 : 0;
for (; i < num_filedes; ++i)
for (; i < num_filedes; ++i) {
printf("%0.2f\t%i\t%i\t%i\n", time_msec, aio_reqs[i]->filedes, aio_reqs[i]->pending, aio_reqs[i]->queued);
}
printf("Num Requests: %i Num Queued: %i num Moved: %i\n\n", data->num_req, data->num_queue, data->num_temp);
eventProcessor.schedule_in(this, HRTIME_MSECONDS(50), ET_CALL);
return EVENT_DONE;
Expand Down Expand Up @@ -306,7 +307,7 @@ aio_queue_req(AIOCallbackInternal *op, int fromAPI = 0)
op->link.next = nullptr;
op->link.prev = nullptr;
#ifdef AIO_STATS
ink_atomic_increment((int *)&data->num_req, 1);
ink_atomic_increment(&data->num_req, 1);
#endif
if (!fromAPI && (!req || req->filedes != op->aiocb.aio_fildes)) {
/* search for the matching file descriptor */
Expand Down Expand Up @@ -423,27 +424,27 @@ ink_aio_thread_num_set(int thread_num)
void *
AIOThreadInfo::aio_thread_main(AIOThreadInfo *thr_info)
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@ywkaras ywkaras Sep 19, 2023

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Not directly relevant to this PR, but thr_info is redundant, it's the same as the this pointer in this function.

{
AIO_Reqs *my_aio_req = thr_info->req;
AIO_Reqs *current_req = nullptr;
AIOCallback *op = nullptr;
AIO_Reqs *my_aio_req = thr_info->req;
AIOCallback *op = nullptr;
ink_mutex_acquire(&my_aio_req->aio_mutex);
for (;;) {
do {
if (TSSystemState::is_event_system_shut_down()) {
ink_mutex_release(&my_aio_req->aio_mutex);
return nullptr;
}
current_req = my_aio_req;
/* check if any pending requests on the atomic list */
aio_move(my_aio_req);
if (!(op = my_aio_req->aio_todo.pop())) {
break;
}
#ifdef AIO_STATS
num_requests--;
current_req->queued--;
ink_atomic_increment((int *)&current_req->pending, 1);
my_aio_req->queued--;
ink_atomic_increment(&my_aio_req->pending, 1);
#endif
ink_mutex_release(&my_aio_req->aio_mutex);
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@ywkaras ywkaras Sep 19, 2023

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Releasing early looks OK.


// update the stats;
if (op->aiocb.aio_lio_opcode == LIO_WRITE) {
Metrics::increment(aio_rsb.write_count);
Expand All @@ -452,11 +453,10 @@ AIOThreadInfo::aio_thread_main(AIOThreadInfo *thr_info)
Metrics::increment(aio_rsb.read_count);
Metrics::increment(aio_rsb.kb_read, op->aiocb.aio_nbytes >> 10);
}
ink_mutex_release(&current_req->aio_mutex);
cache_op((AIOCallbackInternal *)op);
ink_atomic_increment(&current_req->requests_queued, -1);
cache_op(reinterpret_cast<AIOCallbackInternal *>(op));
ink_atomic_increment(&my_aio_req->requests_queued, -1);
#ifdef AIO_STATS
ink_atomic_increment((int *)&current_req->pending, -1);
ink_atomic_increment(&my_aio_req->pending, -1);
#endif
op->link.prev = nullptr;
op->link.next = nullptr;
Expand Down