perf: generalize perf_callchain

[linux-2.6-block.git] / arch / x86 / kernel / stacktrace.c

diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c
index fdd0c6430e5abc97c878d192439447298b2fd06c..9ee98eefc44dec04148dada9c3b8000c016fd738 100644 (file)
--- a/arch/x86/kernel/stacktrace.c
+++ b/arch/x86/kernel/stacktrace.c
@@ -14,30 +14,34 @@ static int save_stack_stack(void *data, char *name)
        return 0;
 }
 
-static void
+static int
 __save_stack_address(void *data, unsigned long addr, bool reliable, bool nosched)
 {
        struct stack_trace *trace = data;
 #ifdef CONFIG_FRAME_POINTER
        if (!reliable)
-               return;
+               return 0;
 #endif
        if (nosched && in_sched_functions(addr))
-               return;
+               return 0;
        if (trace->skip > 0) {
                trace->skip--;
-               return;
+               return 0;
        }
-       if (trace->nr_entries < trace->max_entries)
+       if (trace->nr_entries < trace->max_entries) {
                trace->entries[trace->nr_entries++] = addr;
+               return 0;
+       } else {
+               return -1; /* no more room, stop walking the stack */
+       }
 }
 
-static void save_stack_address(void *data, unsigned long addr, int reliable)
+static int save_stack_address(void *data, unsigned long addr, int reliable)
 {
        return __save_stack_address(data, addr, reliable, false);
 }
 
-static void
+static int
 save_stack_address_nosched(void *data, unsigned long addr, int reliable)
 {
        return __save_stack_address(data, addr, reliable, true);