Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / arch / x86 / kernel / mcount_64.S

diff --git a/kernel/arch/x86/kernel/mcount_64.S b/kernel/arch/x86/kernel/mcount_64.S
index 94ea120..5d9afbc 100644 (file)
--- a/kernel/arch/x86/kernel/mcount_64.S
+++ b/kernel/arch/x86/kernel/mcount_64.S
@@ -180,7 +180,8 @@ GLOBAL(ftrace_graph_call)
        jmp ftrace_stub
 #endif
 
-GLOBAL(ftrace_stub)
+/* This is weak to keep gas from relaxing the jumps */
+WEAK(ftrace_stub)
        retq
 END(ftrace_caller)
 
@@ -278,6 +279,12 @@ trace:
        /* save_mcount_regs fills in first two parameters */
        save_mcount_regs
 
+       /*
+        * When DYNAMIC_FTRACE is not defined, ARCH_SUPPORTS_FTRACE_OPS is not
+        * set (see include/asm/ftrace.h and include/linux/ftrace.h).  Only the
+        * ip and parent ip are used and the list function is called when
+        * function tracing is enabled.
+        */
        call   *ftrace_trace_function
 
        restore_mcount_regs