[patch 4/14] x86, ds: wait before freeing the DS configuration

[Markus Metzger]

After suspending bts tracing, the task is still traced as long as it is
running. The suspend will take effect when the task is scheduled out.

Wait until the traced task becomes inactive before freeing the DS configuration.

Signed-off-by: Markus Metzger <markus.t.metzger@xxxxxxxxx>
---

Index: git-tip/arch/x86/kernel/ds.c
===================================================================
--- git-tip.orig/arch/x86/kernel/ds.c	2009-03-27 07:59:23.000000000 +0100
+++ git-tip/arch/x86/kernel/ds.c	2009-03-27 08:00:41.000000000 +0100
@@ -783,6 +783,14 @@ void ds_release_bts(struct bts_tracer *t
 
 	ds_suspend_bts(tracer);
 
+	/*
+	 * We must wait for the suspend to take effect before we may
+	 * free the tracer and the ds configuration.
+	 */
+	if (tracer->ds.context->task &&
+	    (tracer->ds.context->task != current))
+		wait_task_inactive(tracer->ds.context->task, 0);
+
 	WARN_ON_ONCE(tracer->ds.context->bts_master != tracer);
 	tracer->ds.context->bts_master = NULL;
 
---------------------------------------------------------------------
Intel GmbH
Dornacher Strasse 1
85622 Feldkirchen/Muenchen Germany
Sitz der Gesellschaft: Feldkirchen bei Muenchen
Geschaeftsfuehrer: Douglas Lusk, Peter Gleissner, Hannes Schwaderer
Registergericht: Muenchen HRB 47456 Ust.-IdNr.
VAT Registration No.: DE129385895
Citibank Frankfurt (BLZ 502 109 00) 600119052

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.

--
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/