From f83ac7544fbf7ba3f77c122e16ab5319f75bbdfd Mon Sep 17 00:00:00 2001 From: pengdonglin Date: Tue, 25 Nov 2025 17:34:25 +0800 Subject: function_graph: Enable funcgraph-args and funcgraph-retaddr to work simultaneously Currently, the funcgraph-args and funcgraph-retaddr features are mutually exclusive. This patch resolves this limitation by allowing funcgraph-retaddr to have an args array. To verify the change, use perf to trace vfs_write with both options enabled: Before: # perf ftrace -G vfs_write --graph-opts args,retaddr ...... down_read() { /* <-n_tty_write+0xa3/0x540 */ __cond_resched(); /* <-down_read+0x12/0x160 */ preempt_count_add(); /* <-down_read+0x3b/0x160 */ preempt_count_sub(); /* <-down_read+0x8b/0x160 */ } After: # perf ftrace -G vfs_write --graph-opts args,retaddr ...... down_read(sem=0xffff8880100bea78) { /* <-n_tty_write+0xa3/0x540 */ __cond_resched(); /* <-down_read+0x12/0x160 */ preempt_count_add(val=1); /* <-down_read+0x3b/0x160 */ preempt_count_sub(val=1); /* <-down_read+0x8b/0x160 */ } Cc: Steven Rostedt (Google) Cc: Sven Schnelle Cc: Masami Hiramatsu Cc: Xiaoqin Zhang Link: https://patch.msgid.link/20251125093425.2563849-1-dolinux.peng@gmail.com Signed-off-by: pengdonglin Signed-off-by: Steven Rostedt (Google) --- kernel/trace/trace.h | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) (limited to 'kernel/trace/trace.h') diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 666f9a2c189d..c2b61bcd912f 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -964,7 +964,8 @@ extern int __trace_graph_entry(struct trace_array *tr, extern int __trace_graph_retaddr_entry(struct trace_array *tr, struct ftrace_graph_ent *trace, unsigned int trace_ctx, - unsigned long retaddr); + unsigned long retaddr, + struct ftrace_regs *fregs); extern void __trace_graph_return(struct trace_array *tr, struct ftrace_graph_ret *trace, unsigned int trace_ctx, @@ -2276,4 +2277,25 @@ static inline int rv_init_interface(void) */ #define FTRACE_TRAMPOLINE_MARKER ((unsigned long) INT_MAX) +/* + * This is used to get the address of the args array based on + * the type of the entry. + */ +#define FGRAPH_ENTRY_ARGS(e) \ + ({ \ + unsigned long *_args; \ + struct ftrace_graph_ent_entry *_e = e; \ + \ + if (IS_ENABLED(CONFIG_FUNCTION_GRAPH_RETADDR) && \ + e->ent.type == TRACE_GRAPH_RETADDR_ENT) { \ + struct fgraph_retaddr_ent_entry *_re; \ + \ + _re = (typeof(_re))_e; \ + _args = _re->args; \ + } else { \ + _args = _e->args; \ + } \ + _args; \ + }) + #endif /* _LINUX_KERNEL_TRACE_H */ -- cgit v1.2.3