Merge tag 'pstore-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees...

[cascardo/linux.git] / arch / x86 / events / core.c

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 18a1acf..d31735f 100644 (file)
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -37,6 +37,7 @@
 #include <asm/timer.h>
 #include <asm/desc.h>
 #include <asm/ldt.h>
+#include <asm/unwind.h>
 
 #include "perf_event.h"
 
@@ -2267,39 +2268,26 @@ void arch_perf_update_userpage(struct perf_event *event,
        cyc2ns_read_end(data);
 }
 
-/*
- * callchain support
- */
-
-static int backtrace_stack(void *data, char *name)
-{
-       return 0;
-}
-
-static int backtrace_address(void *data, unsigned long addr, int reliable)
-{
-       struct perf_callchain_entry_ctx *entry = data;
-
-       return perf_callchain_store(entry, addr);
-}
-
-static const struct stacktrace_ops backtrace_ops = {
-       .stack                  = backtrace_stack,
-       .address                = backtrace_address,
-       .walk_stack             = print_context_stack_bp,
-};
-
 void
 perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs)
 {
+       struct unwind_state state;
+       unsigned long addr;
+
        if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
                /* TODO: We don't support guest os callchain now */
                return;
        }
 
-       perf_callchain_store(entry, regs->ip);
+       if (perf_callchain_store(entry, regs->ip))
+               return;
 
-       dump_trace(NULL, regs, NULL, 0, &backtrace_ops, entry);
+       for (unwind_start(&state, current, regs, NULL); !unwind_done(&state);
+            unwind_next_frame(&state)) {
+               addr = unwind_get_return_address(&state);
+               if (!addr || perf_callchain_store(entry, addr))
+                       return;
+       }
 }
 
 static inline int