perf/x86: Convert perf_callchain_kernel() to use the new unwinder

Convert perf_callchain_kernel() to use the new unwinder.  dump_trace()
has been deprecated.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a2df0c4f09b3d438e11b41681f10b0775a819a7f.1474045023.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 477dc38b62b1af5f4d0ee31327a3f172326507e8..0a8bd7fcdbed9f533ee38c0586b88d338ee721a4 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"
 
@@ -2247,31 +2248,12 @@ void arch_perf_update_userpage(struct perf_event *event,
        cyc2ns_read_end(data);
 }
 
-/*
- * callchain support
- */
-
-static int backtrace_stack(void *data, const 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;
@@ -2280,7 +2262,12 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re
        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