the attached patch adds two scheduler related fixes:
- changes the migration code to use struct completion. Andrew pointed out
that there might be a small window in where the up() touches the
semaphore while the waiting task goes on and frees its stack. And
completion is more suited for this kind of stuff anyway.
- removes two unneeded exports, pointed out by Andrew.
Ingo
--- linux/kernel/sched.c.orig Fri Aug 30 09:34:34 2002
+++ linux/kernel/sched.c Fri Aug 30 09:35:49 2002
@@ -1901,7 +1901,7 @@
typedef struct {
list_t list;
task_t *task;
- struct semaphore sem;
+ struct completion done;
} migration_req_t;
/*
@@ -1945,13 +1945,13 @@
task_rq_unlock(rq, &flags);
goto out;
}
- init_MUTEX_LOCKED(&req.sem);
+ init_completion(&req.done);
req.task = p;
list_add(&req.list, &rq->migration_queue);
task_rq_unlock(rq, &flags);
wake_up_process(rq->migration_thread);
- down(&req.sem);
+ wait_for_completion(&req.done);
out:
preempt_enable();
}
@@ -2032,7 +2032,7 @@
double_rq_unlock(rq_src, rq_dest);
local_irq_restore(flags);
- up(&req->sem);
+ complete(&req->done);
}
}
--- linux/kernel/ksyms.c.orig Fri Aug 30 09:37:36 2002
+++ linux/kernel/ksyms.c Fri Aug 30 09:37:38 2002
@@ -496,8 +496,6 @@
#endif
EXPORT_SYMBOL(kstat);
-EXPORT_SYMBOL(nr_running);
-EXPORT_SYMBOL(nr_context_switches);
/* misc */
EXPORT_SYMBOL(panic);
-
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This archive was generated by hypermail 2b29 : Sat Aug 31 2002 - 22:00:30 EST