[PATCH][2.6.8-rc4-mm1] perfctr SMP hang fix

[Mikael Pettersson]

Andrew,

This patch fixes a critical SMP bug in the perfctr
inheritance fix I sent yesterday. I added a spinlock
to the perfctr state, but forgot to initialise it,
which results in a hard hang on SMP the first time
someone tries to program their perfctrs. It works
on UP, which is why I didn't detect it before :-(

Signed-off-by: Mikael Pettersson <mikpe@xxxxxxxxx>

 drivers/perfctr/virtual.c |    1 +
 1 files changed, 1 insertion(+)

diff -ruN linux-2.6.8-rc4-mm1/drivers/perfctr/virtual.c linux-2.6.8-rc4-mm1.perfctr-spinlock-fix/drivers/perfctr/virtual.c
--- linux-2.6.8-rc4-mm1/drivers/perfctr/virtual.c	2004-08-10 13:52:17.000000000 +0200
+++ linux-2.6.8-rc4-mm1.perfctr-spinlock-fix/drivers/perfctr/virtual.c	2004-08-10 13:53:57.644784000 +0200
@@ -156,6 +156,7 @@
 		atomic_set(&perfctr->count, 1);
 		vperfctr_init_bad_cpus_allowed(perfctr);
 		spin_lock_init(&perfctr->owner_lock);
+		spin_lock_init(&perfctr->children_lock);
 	}
 	return perfctr;
 }
-
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