diff options
| -rw-r--r-- | include/linux/ftrace.h | 16 | ||||
| -rw-r--r-- | kernel/trace/ftrace.c | 4 |
2 files changed, 18 insertions, 2 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index a69f363b61bf..832e65f06754 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -643,6 +643,22 @@ static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; } extern int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr); +/** + * ftrace_need_init_nop - return whether nop call sites should be initialized + * + * Normally the compiler's -mnop-mcount generates suitable nops, so we don't + * need to call ftrace_init_nop() if the code is built with that flag. + * Architectures where this is not always the case may define their own + * condition. + * + * Return must be: + * 0 if ftrace_init_nop() should be called + * Nonzero if ftrace_init_nop() should not be called + */ + +#ifndef ftrace_need_init_nop +#define ftrace_need_init_nop() (!__is_defined(CC_USING_NOP_MCOUNT)) +#endif /** * ftrace_init_nop - initialize a nop call site diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7b180f61e6d3..7efbc8aaf7f6 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3100,6 +3100,7 @@ ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) { + bool init_nop = ftrace_need_init_nop(); struct ftrace_page *pg; struct dyn_ftrace *p; u64 start, stop; @@ -3138,8 +3139,7 @@ static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) * Do the initial record conversion from mcount jump * to the NOP instructions. */ - if (!__is_defined(CC_USING_NOP_MCOUNT) && - !ftrace_nop_initialize(mod, p)) + if (init_nop && !ftrace_nop_initialize(mod, p)) break; update_cnt++; |