Re: 2.6.13-rt3

From: Steven Rostedt
Date: Thu Sep 01 2005 - 11:25:44 EST


Ingo,

Here's a patch to fix some of the problems when defining ALL_TASKS_PI.
The pi_setprio logic is currently incorrect. This should fix that. I
converted ALL_TASKS_PI to a constant number, so that it can be used in
if statements.

-- Steve

Note: I compiled this, but I haven't run it yet. I'll run it right after
I send this note and respond how it worked.

Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx>

Index: linux_realtime_goliath/kernel/rt.c
===================================================================
--- linux_realtime_goliath/kernel/rt.c (revision 314)
+++ linux_realtime_goliath/kernel/rt.c (working copy)
@@ -104,7 +104,7 @@
* in the system fall under PI handling. Normally only SCHED_FIFO/RR
* tasks are PI-handled:
*/
-#define ALL_TASKS_PI
+#define ALL_TASKS_PI 1

#ifdef CONFIG_RT_DEADLOCK_DETECT
# define __EIP_DECL__ , unsigned long eip
@@ -663,7 +663,7 @@

#endif

-#if defined(ALL_TASKS_PI) && defined(CONFIG_RT_DEADLOCK_DETECT)
+#if ALL_TASKS_PI && defined(CONFIG_RT_DEADLOCK_DETECT)

static void
check_pi_list_present(struct rt_mutex *lock, struct rt_mutex_waiter *waiter,
@@ -674,7 +674,6 @@

__raw_spin_lock(&old_owner->task->pi_lock);
TRACE_WARN_ON_LOCKED(plist_empty(&waiter->pi_list));
- TRACE_WARN_ON_LOCKED(lock_owner(lock));

plist_for_each(curr1, &old_owner->task->pi_waiters) {
w = plist_entry(curr1, struct rt_mutex_waiter, pi_list);
@@ -851,7 +850,7 @@
__raw_spin_lock(&l->wait_lock);

TRACE_BUG_ON_LOCKED(!lock_owner(l));
- if (rt_task(p) && plist_empty(&w->pi_list)) {
+ if ((ALL_TASKS_PI || rt_task(p)) && plist_empty(&w->pi_list)) {
TRACE_BUG_ON_LOCKED(was_rt);
plist_init(&w->pi_list, prio);
plist_add(&w->pi_list, &lock_owner(l)->task->pi_waiters);
@@ -868,7 +867,7 @@
* (TODO: this can be unfair to SCHED_NORMAL tasks if they
* get PI handled.)
*/
- if (!rt_task(p) && !plist_empty(&w->pi_list)) {
+ if (!ALL_TASKS_PI && !rt_task(p) && !plist_empty(&w->pi_list)) {
TRACE_BUG_ON_LOCKED(!was_rt);
plist_del(&w->pi_list, &lock_owner(l)->task->pi_waiters);
plist_del(&w->list, &l->wait_list);
@@ -970,7 +969,7 @@
*/
TRACE_BUG_ON_LOCKED(!spin_is_locked(&task->pi_lock));
TRACE_BUG_ON_LOCKED(!spin_is_locked(&lock->wait_lock));
-#ifndef ALL_TASKS_PI
+#if !ALL_TASKS_PI
if (!rt_task(task)) {
plist_add(&waiter->list, &lock->wait_list);
set_lock_owner_pending(lock);
@@ -1083,7 +1082,7 @@
#endif
trace_special_pid(waiter->ti->task->pid, waiter->ti->task->prio, 0);

-#ifdef ALL_TASKS_PI
+#if ALL_TASKS_PI
check_pi_list_present(lock, waiter, old_owner);
#endif
new_owner = waiter->ti;
@@ -1543,7 +1542,7 @@
list_del_init(&lock->held_list);
#endif

-#ifdef ALL_TASKS_PI
+#if ALL_TASKS_PI
if (plist_empty(&lock->wait_list))
check_pi_list_empty(lock, lock_owner(lock));
#endif


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/