perf: Humanize the number of contexts

Instead of hardcoding the number of contexts for the recursions
barriers, define a cpp constant to make the code more
self-explanatory.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 75ab8a2df6b2..f416aef242c3 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -1772,7 +1772,7 @@ struct callchain_cpus_entries {
         struct perf_callchain_entry     *cpu_entries[0];
 };
 
-static DEFINE_PER_CPU(int, callchain_recursion[4]);
+static DEFINE_PER_CPU(int, callchain_recursion[PERF_NR_CONTEXTS]);
 static atomic_t nr_callchain_events;
 static DEFINE_MUTEX(callchain_mutex);
 struct callchain_cpus_entries *callchain_cpus_entries;
@@ -1828,7 +1828,7 @@ static int alloc_callchain_buffers(void)
         if (!entries)
                 return -ENOMEM;
 
-        size = sizeof(struct perf_callchain_entry) * 4;
+        size = sizeof(struct perf_callchain_entry) * PERF_NR_CONTEXTS;
 
         for_each_possible_cpu(cpu) {
                 entries->cpu_entries[cpu] = kmalloc_node(size, GFP_KERNEL,