perf, x86: Fix silly bug in data store buffer allocation

Fix up the ds allocation error path, where we could free @buffer before
we used it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: paulus@samba.org
Cc: eranian@google.com
Cc: robert.richter@amd.com
Cc: fweisbec@gmail.com
LKML-Reference: <20100305154128.813452402@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/cpu/perf_event_intel_ds.c

@@ -127,10 +127,8 @@ static int reserve_ds_buffers(void)
 
 		err = -ENOMEM;
 		ds = kzalloc(sizeof(*ds), GFP_KERNEL);
-		if (unlikely(!ds)) {
-			kfree(buffer);
+		if (unlikely(!ds))
 			break;
-		}
 		per_cpu(cpu_hw_events, cpu).ds = ds;
 
 		if (x86_pmu.bts) {