perf, x86: Extract DS alloc/free functions

Again, mostly a cleanup to unclutter the reserve_ds_buffer() code.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Stephane Eranian <eranian@google.com>
LKML-Reference: <20101019134808.304495776@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 26 insertions, 14 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 14d98bd52055..3c86f4d2f02d 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -148,6 +148,30 @@ static void release_bts_buffer(int cpu)
         ds->bts_buffer_base = 0;
 }
 
+static int alloc_ds_buffer(int cpu)
+{
+        struct debug_store *ds;
+
+        ds = kzalloc(sizeof(*ds), GFP_KERNEL);
+        if (unlikely(!ds))
+                return -ENOMEM;
+
+        per_cpu(cpu_hw_events, cpu).ds = ds;
+
+        return 0;
+}
+
+static void release_ds_buffer(int cpu)
+{
+        struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
+
+        if (!ds)
+                return;
+
+        per_cpu(cpu_hw_events, cpu).ds = NULL;
+        kfree(ds);
+}
+
 static void release_ds_buffers(void)
 {
         int cpu;
@@ -160,16 +184,9 @@ static void release_ds_buffers(void)
                 fini_debug_store_on_cpu(cpu);
 
         for_each_possible_cpu(cpu) {
-                struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
-
-                if (!ds)
-                        continue;
-
                 release_pebs_buffer(cpu);
                 release_bts_buffer(cpu);
-
-                per_cpu(cpu_hw_events, cpu).ds = NULL;
-                kfree(ds);
+                release_ds_buffer(cpu);
         }
         put_online_cpus();
 }
@@ -184,13 +201,8 @@ static int reserve_ds_buffers(void)
         get_online_cpus();
 
         for_each_possible_cpu(cpu) {
-                struct debug_store *ds;
-
-                err = -ENOMEM;
-                ds = kzalloc(sizeof(*ds), GFP_KERNEL);
-                if (unlikely(!ds))
+                if (alloc_ds_buffer(cpu))
                         break;
-                per_cpu(cpu_hw_events, cpu).ds = ds;
 
                 if (alloc_bts_buffer(cpu))
                         break;