perf core: Add perf_callchain_store_context() helper

We need have different helpers to account how many contexts we have in
the sample and for real addresses, so do it now as a prep patch, to
ease review.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-q964tnyuqrxw5gld18vizs3c@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

arch/powerpc/perf/callchain.c

@@ -76,7 +76,7 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re
 			next_ip = regs->nip;
 			lr = regs->link;
 			level = 0;
-			perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+			perf_callchain_store_context(entry, PERF_CONTEXT_KERNEL);
 
 		} else {
 			if (level == 0)
@@ -274,7 +274,7 @@ static void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
 			    read_user_stack_64(&uregs[PT_R1], &sp))
 				return;
 			level = 0;
-			perf_callchain_store(entry, PERF_CONTEXT_USER);
+			perf_callchain_store_context(entry, PERF_CONTEXT_USER);
 			perf_callchain_store(entry, next_ip);
 			continue;
 		}
@@ -473,7 +473,7 @@ static void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry,
 			    read_user_stack_32(&uregs[PT_R1], &sp))
 				return;
 			level = 0;
-			perf_callchain_store(entry, PERF_CONTEXT_USER);
+			perf_callchain_store_context(entry, PERF_CONTEXT_USER);
 			perf_callchain_store(entry, next_ip);
 			continue;
 		}

include/linux/perf_event.h

@@ -1079,6 +1079,8 @@ extern void put_callchain_buffers(void);
 
 extern int sysctl_perf_event_max_stack;
 
+#define perf_callchain_store_context(ctx, context) perf_callchain_store(ctx, context)
+
 static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
 {
 	if (ctx->nr < ctx->max_stack) {

kernel/events/callchain.c

@@ -200,7 +200,7 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
 
 	if (kernel && !user_mode(regs)) {
 		if (add_mark)
-			perf_callchain_store(&ctx, PERF_CONTEXT_KERNEL);
+			perf_callchain_store_context(&ctx, PERF_CONTEXT_KERNEL);
 		perf_callchain_kernel(&ctx, regs);
 	}
 
@@ -217,7 +217,7 @@ get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
 				goto exit_put;
 
 			if (add_mark)
-				perf_callchain_store(&ctx, PERF_CONTEXT_USER);
+				perf_callchain_store_context(&ctx, PERF_CONTEXT_USER);
 			perf_callchain_user(&ctx, regs);
 		}
 	}