ComputerSurge/bind9
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Make sure all priority tasks are done before entering normal execution

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This commit is contained in:
Witold Kręcicki
2018-10-22 10:57:05 +00:00
parent 8fffa3760d
commit 0e1e295ddb
1 changed files with 26 additions and 6 deletions
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32
lib/isc/task.c
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@@ -43,6 +43,14 @@
#include <openssl/err.h>
#endif
/*
* Task manager is built around 'as little locking as possible' concept.
* Each thread has his own queue of tasks to be run, if a task is in running
* state it will stay on the runner it's currently on, if a task is in idle
* state it can be woken up on a specific runner with isc_task_sendto - that
* helps with data locality on CPU.
*/
#ifdef ISC_TASK_TRACE
#define XTRACE(m) fprintf(stderr, "task %p thread %lu: %s\n", \
task, isc_thread_self(), (m))
@@ -95,7 +103,7 @@ struct isc__task {
isc_time_t tnow;
char name[16];
void * tag;
int threadid;
unsigned int threadid;
/* Locked by task manager lock. */
LINK(isc__task_t) link;
LINK(isc__task_t) ready_link;
@@ -911,7 +919,7 @@ push_readyq(isc__taskmgr_t *manager, isc__task_t *task, int c) {
}
static void
dispatch(isc__taskmgr_t *manager, int threadid) {
dispatch(isc__taskmgr_t *manager, unsigned int threadid) {
isc__task_t *task;
REQUIRE(VALID_MANAGER(manager));
@@ -1191,10 +1199,22 @@ dispatch(isc__taskmgr_t *manager, int threadid) {
* we're stuck. Automatically drop privileges at that
* point and continue with the regular ready queue.
*/
if (manager->tasks_running == 0 && empty_readyq(manager, threadid)) {
manager->mode = isc_taskmgrmode_normal;
for (unsigned i=0; i < manager->workers; i++) {
BROADCAST(&manager->queues[i].work_available);
if (atomic_load(&manager->tasks_running) == 0 && manager->mode != isc_taskmgrmode_normal) {
bool empty = true;
for (unsigned i=0; i<manager->workers && empty; i++) {
if (i != threadid) {
LOCK(&manager->queues[i].lock);
}
empty &= empty_readyq(manager, i);
if (i != threadid) {
UNLOCK(&manager->queues[i].lock);
}
}
if (empty) {
manager->mode = isc_taskmgrmode_normal;
for (unsigned i=0; i < manager->workers; i++) {
BROADCAST(&manager->queues[i].work_available);
}
}
}
}