Page MenuHomeFreeBSD
Files F135460108

D15914.id44923.diff
No OneTemporary
Actions

D15914.id44923.diff
View Options

Index: head/sys/kern/kern_clock.c
===================================================================
--- head/sys/kern/kern_clock.c
+++ head/sys/kern/kern_clock.c
@@ -185,12 +185,70 @@
static int sleepfreq = 3;
static void
+deadlres_td_on_lock(struct proc *p, struct thread *td, int blkticks)
+{
+ int tticks;
+
+ sx_assert(&allproc_lock, SX_LOCKED);
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+ THREAD_LOCK_ASSERT(td, MA_OWNED);
+ /*
+ * The thread should be blocked on a turnstile, simply check
+ * if the turnstile channel is in good state.
+ */
+ MPASS(td->td_blocked != NULL);
+
+ tticks = ticks - td->td_blktick;
+ if (tticks > blkticks)
+ /*
+ * Accordingly with provided thresholds, this thread is stuck
+ * for too long on a turnstile.
+ */
+ panic("%s: possible deadlock detected for %p, "
+ "blocked for %d ticks\n", __func__, td, tticks);
+}
+
+static void
+deadlres_td_sleep_q(struct proc *p, struct thread *td, int slpticks)
+{
+ void *wchan;
+ int i, slptype, tticks;
+
+ sx_assert(&allproc_lock, SX_LOCKED);
+ PROC_LOCK_ASSERT(p, MA_OWNED);
+ THREAD_LOCK_ASSERT(td, MA_OWNED);
+ /*
+ * Check if the thread is sleeping on a lock, otherwise skip the check.
+ * Drop the thread lock in order to avoid a LOR with the sleepqueue
+ * spinlock.
+ */
+ wchan = td->td_wchan;
+ tticks = ticks - td->td_slptick;
+ slptype = sleepq_type(wchan);
+ if ((slptype == SLEEPQ_SX || slptype == SLEEPQ_LK) &&
+ tticks > slpticks) {
+
+ /*
+ * Accordingly with provided thresholds, this thread is stuck
+ * for too long on a sleepqueue.
+ * However, being on a sleepqueue, we might still check for the
+ * blessed list.
+ */
+ for (i = 0; blessed[i] != NULL; i++)
+ if (!strcmp(blessed[i], td->td_wmesg))
+ return;
+
+ panic("%s: possible deadlock detected for %p, "
+ "blocked for %d ticks\n", __func__, td, tticks);
+ }
+}
+
+static void
deadlkres(void)
{
struct proc *p;
struct thread *td;
- void *wchan;
- int blkticks, i, slpticks, slptype, tryl, tticks;
+ int blkticks, slpticks, tryl;
tryl = 0;
for (;;) {
@@ -198,14 +256,15 @@
slpticks = slptime_threshold * hz;
/*
- * Avoid to sleep on the sx_lock in order to avoid a possible
- * priority inversion problem leading to starvation.
+ * Avoid to sleep on the sx_lock in order to avoid a
+ * possible priority inversion problem leading to
+ * starvation.
* If the lock can't be held after 100 tries, panic.
*/
if (!sx_try_slock(&allproc_lock)) {
if (tryl > 100)
- panic("%s: possible deadlock detected on allproc_lock\n",
- __func__);
+ panic("%s: possible deadlock detected "
+ "on allproc_lock\n", __func__);
tryl++;
pause("allproc", sleepfreq * hz);
continue;
@@ -218,80 +277,15 @@
continue;
}
FOREACH_THREAD_IN_PROC(p, td) {
-
thread_lock(td);
- if (TD_ON_LOCK(td)) {
-
- /*
- * The thread should be blocked on a
- * turnstile, simply check if the
- * turnstile channel is in good state.
- */
- MPASS(td->td_blocked != NULL);
-
- tticks = ticks - td->td_blktick;
- thread_unlock(td);
- if (tticks > blkticks) {
-
- /*
- * Accordingly with provided
- * thresholds, this thread is
- * stuck for too long on a
- * turnstile.
- */
- PROC_UNLOCK(p);
- sx_sunlock(&allproc_lock);
- panic("%s: possible deadlock detected for %p, blocked for %d ticks\n",
- __func__, td, tticks);
- }
- } else if (TD_IS_SLEEPING(td) &&
- TD_ON_SLEEPQ(td)) {
-
- /*
- * Check if the thread is sleeping on a
- * lock, otherwise skip the check.
- * Drop the thread lock in order to
- * avoid a LOR with the sleepqueue
- * spinlock.
- */
- wchan = td->td_wchan;
- tticks = ticks - td->td_slptick;
- thread_unlock(td);
- slptype = sleepq_type(wchan);
- if ((slptype == SLEEPQ_SX ||
- slptype == SLEEPQ_LK) &&
- tticks > slpticks) {
-
- /*
- * Accordingly with provided
- * thresholds, this thread is
- * stuck for too long on a
- * sleepqueue.
- * However, being on a
- * sleepqueue, we might still
- * check for the blessed
- * list.
- */
- tryl = 0;
- for (i = 0; blessed[i] != NULL;
- i++) {
- if (!strcmp(blessed[i],
- td->td_wmesg)) {
- tryl = 1;
- break;
- }
- }
- if (tryl != 0) {
- tryl = 0;
- continue;
- }
- PROC_UNLOCK(p);
- sx_sunlock(&allproc_lock);
- panic("%s: possible deadlock detected for %p, blocked for %d ticks\n",
- __func__, td, tticks);
- }
- } else
- thread_unlock(td);
+ if (TD_ON_LOCK(td))
+ deadlres_td_on_lock(p, td,
+ blkticks);
+ else if (TD_IS_SLEEPING(td) &&
+ TD_ON_SLEEPQ(td))
+ deadlres_td_sleep_q(p, td,
+ slpticks);
+ thread_unlock(td);
}
PROC_UNLOCK(p);
}

File Metadata

Mime Type
text/plain
Expires
Tue, Nov 11, 1:25 AM (19 h, 22 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
25131932
Default Alt Text
D15914.id44923.diff (4 KB)

Event Timeline