script: Make native script disable uftrace record

This patch makes the given script to disable the actual uftrace record to shared memory. It allows the script control the behavior of uftrace. Signed-off-by: Honggyu Kim <[email protected]>
namhyung · Feb 20, 2023 · 6494fc0 · 6494fc0
1 parent 58bcbca
commit 6494fc0
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Showing 2 changed files with 7 additions and 1 deletion.
diff --git a/libmcount/mcount.c b/libmcount/mcount.c
@@ -1135,7 +1135,7 @@ void mcount_exit_filter_record(struct mcount_thread_data *mtdp, struct mcount_re
 			mtdp->record_idx--;
 
 		if (!mcount_enabled)
-			return;
+			goto out;
 
 		if (!(rstack->flags & MCOUNT_FL_RETVAL))
 			retval = NULL;
@@ -1179,6 +1179,7 @@ void mcount_exit_filter_record(struct mcount_thread_data *mtdp, struct mcount_re
 				mtdp->nr_events = k; /* invalidate sync events */
 		}
 
+out:
 		/* script hooking for function exit */
 		if (script_str)
 			script_hook_exit(mtdp, rstack);
@@ -1755,6 +1756,8 @@ static void mcount_script_init(enum uftrace_pattern_type patt_type)
 
 	if (script_init(&info, patt_type) < 0)
 		script_str = NULL;
+	else if (!info.record)
+		mcount_enabled = false;
 }
 
 static int agent_init(struct sockaddr_un *addr)

diff --git a/scripts/info.c b/scripts/info.c
@@ -9,6 +9,9 @@ void uftrace_begin(struct uftrace_script_info *sc_info)
 	printf("%s\n", sc_info->version);
 	printf("%s\n", sc_info->name);
 	printf("%s\n", sc_info->cmds);
+
+	/* disable actual data record by uftrace */
+	sc_info->record = false;
 }
 
 void uftrace_entry(struct uftrace_script_base_ctx *sc_ctx)