ktrace: Have synthetic event creation do deltas

Allow the create synthetic event allow fields to compare the start and end
events.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

1 files changed, 229 insertions, 67 deletions

diff --git a/src/create.c b/src/create.c
index bd851d8..6e6d9d2 100644
--- a/src/create.c
+++ b/src/create.c
@@ -271,22 +271,44 @@ static int usage_synthetic(struct ccli *ccli)
 		    "#  match system/event2 fields. Then add the fields of the synthetic event\n"
 		    "#  on how they will map to the other fields.\n#\n"
 		    "#  A synthetic event field may also equal timestamps:\n"
-		    "#    start=system/event.TIMESTAMP\n#\n"
+		    "#    start=system/event.TIMESTAMP\n"
+		    "#    start=system/event.TIMESTAMP_USECS\n#\n"
 		    "#  Or even a delta:\n"
 		    "#    delta=system/event.TIMESTAMP-system2/event2.TIMESTAMP\n"
 		);
 	return 0;
 }
 
+static char *check_ts(char *val)
+{
+	if (strcmp(val, "TIMESTAMP") == 0)
+		val = TRACEFS_HIST_TIMESTAMP;
+	else if ((strcmp(val, "TIMESTAMP_USECS") == 0) ||
+		 strcmp(val, "TIMESTAMP_USEC") == 0)
+		val = TRACEFS_HIST_TIMESTAMP_USECS;
+	return val;
+}
+
 int add_synth_field(struct ccli *ccli, struct tracefs_synth *synth,
 		    char *start_system, char *start_event,
 		    char *end_system, char *end_event, char *field)
 {
 	char *system;
+	char *system2;
 	char *event;
+	char *event2;
+	bool start1;
+	bool start2;
 	char *name;
 	char *val;
+	char *val2;
 	char *sav;
+	char *p;
+	int ret;
+
+	p = strchr(field, '-');
+	if (p)
+		*p = '\0';
 
 	name = strtok_r(field, "=", &sav);
 	system = strtok_r(NULL, "/", &sav);
@@ -301,25 +323,84 @@ int add_synth_field(struct ccli *ccli, struct tracefs_synth *synth,
 		return -1;
 	}
 
+
 	val = strtok_r(NULL, ".", &sav);
-	if (!system) {
+	if (!val) {
 		ccli_printf(ccli, "# Missing .field in '%s' \n", event);
 		return -1;
 	}
 
+	val = check_ts(val);
+
 	if ((strcmp(system, start_system) == 0) &&
 	    (strcmp(event, start_event) == 0)) {
-		return tracefs_synth_add_start_field(synth, val, name);
-	}
+		start1 = true;
 
-	if ((strcmp(system, end_system) == 0) &&
-	    (strcmp(event, end_event) == 0)) {
-		return tracefs_synth_add_end_field(synth, val, name);
+	} else if ((strcmp(system, end_system) == 0) &&
+		   (strcmp(event, end_event) == 0)) {
+		start1 = false;
+	} else {
+		ccli_printf(ccli, "# %s/%s does not match either start or end events\n",
+			    system, event);
+		return -1;
 	}
 
-	ccli_printf(ccli, "# %s/%s does not match either start or end events\n",
-		    system, event);
-	return -1;
+	if (p) {
+		p++;
+		system2 = strtok_r(p, "/", &sav);
+		if (!system2) {
+			ccli_printf(ccli, "# Missing '/' in '%s'\n", p);
+			return -1;
+		}
+
+		event2 = strtok_r(NULL, ".", &sav);
+		if (!event) {
+			ccli_printf(ccli, "# Missing /event.field in '%s'\n", system2);
+			return -1;
+		}
+
+		val2 = strtok_r(NULL, ".", &sav);
+		if (!val2) {
+			ccli_printf(ccli, "# Missing .field in '%s' \n", event2);
+			return -1;
+		}
+
+		val2 = check_ts(val2);
+
+		if ((strcmp(system2, start_system) == 0) &&
+		    (strcmp(event2, start_event) == 0)) {
+			start2 = true;
+
+		} else if ((strcmp(system2, end_system) == 0) &&
+			   (strcmp(event2, end_event) == 0)) {
+			start2 = false;
+		} else {
+			ccli_printf(ccli, "# %s/%s does not match either start or end events\n",
+				    system2, event2);
+			return -1;
+		}
+
+		if (start1 == start2) {
+			ccli_printf(ccli, "# Can not compare with the same event\n");
+			return -1;
+		}
+
+		if (start2) {
+			p = val;
+			val = val2;
+			val2 = p;
+		}
+		printf("val=%s val2=%s name=%s\n", val, val2, name);
+		ret = tracefs_synth_add_compare_field(synth, val, val2,
+						      TRACEFS_SYNTH_DELTA_END, name);
+		if (ret < 0)
+			perror("add_compare_field");
+		return ret;
+	}
+	if (start1)
+		return tracefs_synth_add_start_field(synth, val, name);
+	else
+		return tracefs_synth_add_end_field(synth, val, name);
 }
 
 static int create_synthetic(struct ccli *ccli, void *data,
@@ -692,6 +773,7 @@ static int event_completion(struct ccli *ccli, struct tep_handle *tep,
 		systems = tracefs_event_systems(NULL);
 		if (!systems)
 			return 0;
+
 		for (i = 0; ret >= 0 && systems[i]; i++)
 			ret = ccli_list_add(ccli, list, &cnt, systems[i]);
 
@@ -836,31 +918,19 @@ static int append_event_field(struct ccli *ccli, struct tep_handle *tep, char **
 	return field_completion(ccli, event, list, ename, &cnt);
 }
 
-static int append_field_ts(struct ccli *ccli, struct tep_handle *tep, char ***list,
-			      char *ename)
+static int append_field_completion(struct ccli *ccli, char ***list, int *cnt,
+				   struct tep_handle *tep, char *p, char *str,
+				   char *ename, char *match)
 {
 	struct tep_event *event;
-	int cnt = 0;
-	char *e;
-	char *p;
 	int ret;
+	int i, r;
 
-	/* Find start of the event */
-	e = strchr(ename, '=');
-	if (!e) // should not happen
-		return 0;
-	e++;
-
-	/* Find the end of the event */
-	for (p = e; *p && *p != '.'; p++)
-		;
-	if (!*p) // Should not happen!
-		return 0;
 	*p = '\0';
 
-	event = find_event(tep, e);
+	event = find_event(tep, ename);
 	if (!event) {
-		ccli_printf(ccli, "\n# Event %s not found\n", e);
+		ccli_printf(ccli, "\n# Event %s not found\n", ename);
 		ccli_line_refresh(ccli);
 		return 0;
 	}
@@ -868,23 +938,137 @@ static int append_field_ts(struct ccli *ccli, struct tep_handle *tep, char ***li
 	*p = '.';
 	p[1] = '\0';
 
-	ret = field_completion(ccli, event, list, ename, &cnt);
+	ret = field_completion(ccli, event, list, str, cnt);
 
 	if (ret > 0) {
-		ret = ccli_list_add_printf(ccli, list, &cnt,
-				     "%sTIMESTAMP", ename);
+		ret = ccli_list_add_printf(ccli, list, cnt,
+				     "%sTIMESTAMP", str);
+		ret = ccli_list_add_printf(ccli, list, cnt,
+				     "%sTIMESTAMP_USECS", str);
 		if (ret < 0)
-			ccli_list_free(ccli, list, cnt);
+			ccli_list_free(ccli, list, *cnt);
 	}
+	if (ret > 0) {
+		/* If there's any matches, add the "subtraction" */
+		for (i = 0, r = ret; ret > 0 && i < r; i++) {
+			if (strcmp((*list)[i], match) == 0) {
+				ret = ccli_list_add_printf(ccli, list, cnt,
+							   "%s-", match);
+				break;
+			}
+		}
+	}
+	if (ret < 0)
+		ccli_list_free(ccli, list, *cnt);
+
+	match[strlen(match)] = CCLI_NOSPACE;
 	return ret;
 }
 
+static int synth_event_match(struct ccli *ccli, char ***list, int *cnt,
+			     struct tep_handle *tep, char *prefix,
+			     char *ename1, char *ename2)
+{
+	struct tep_event *event1;
+	struct tep_event *event2;
+	char *p;
+
+	/* Can only be one of the previous events */
+	p = strchr(ename1, '.');
+	if (!p) {
+		ccli_printf(ccli, "# %s needs a field\n", ename1);
+		ccli_line_refresh(ccli);
+		return 0;
+	}
+	*p = '\0';
+	event1 = find_event(tep, ename1);
+	if (!event1) {
+		ccli_printf(ccli, "\n# Event %s not found\n", ename1);
+		ccli_line_refresh(ccli);
+		return 0;
+	}
+	p = strchr(ename2, '.');
+	if (!p) {
+		ccli_printf(ccli, "\n# %s needs a field\n", ename2);
+		ccli_line_refresh(ccli);
+		return 0;
+	}
+	*p = '\0';
+	event2 = find_event(tep, ename2);
+	if (!event2) {
+		ccli_printf(ccli, "\n# Event %s not found\n", ename2);
+		ccli_line_refresh(ccli);
+		return 0;
+	}
+
+	ccli_list_add_printf(ccli, list, cnt, "%s%s/%s",
+			     prefix, event1->system, event1->name);
+	return ccli_list_add_printf(ccli, list, cnt, "%s%s/%s",
+				    prefix, event2->system, event2->name);
+}
+
+static int append_field_cal(struct ccli *ccli, struct tep_handle *tep, char ***list,
+			    char *ename1, char *ename2,
+			    char *str, char *match)
+{
+	char *prefix;
+	int cnt = 0;
+	char *e;
+	char *p;
+	int ret;
+
+	/* Find start of the event */
+	e = strchr(str, '-');
+	if (!e) // should not happen
+		return 0;
+
+	*e = 0;
+	ret = asprintf(&prefix, "%s-", str);
+	if (ret < 0)
+		return 0;
+	*e = '-';
+	e++;
+	p = strchr(e, '.');
+	if (!p) {
+		ret = synth_event_match(ccli, list, &cnt,
+					tep, prefix, ename1, ename2);
+		free(prefix);
+		match[strlen(match)] = '.';
+		return ret;
+	}
+	free(prefix);
+
+	return append_field_completion(ccli, list, &cnt, tep, p, str, e, match);
+}
+
+static int append_field_ts(struct ccli *ccli, struct tep_handle *tep, char ***list,
+			      char *str, char *match)
+{
+	int cnt = 0;
+	char *e;
+	char *p;
+
+	/* Find start of the event */
+	e = strchr(str, '=');
+	if (!e) // should not happen
+		return 0;
+	e++;
+
+	/* Find the end of the event */
+	for (p = e; *p && *p != '.'; p++)
+		;
+	if (!*p) // Should not happen!
+		return 0;
+
+	return append_field_completion(ccli, list, &cnt, tep, p, str, e, match);
+}
+
 static int synthetic_completion(struct ccli *ccli, void *data,
 				int argc, char **argv,
 				char ***list, int word, char *match)
 {
 	struct tep_handle *tep = data;
-	struct tep_event *event1, *event2;
+	char *prefix;
 	char *p;
 	int cnt = 0;
 	int len;
@@ -915,45 +1099,23 @@ static int synthetic_completion(struct ccli *ccli, void *data,
 			ccli_line_refresh(ccli);
 			return 0;
 		}
+		if (strchr(p, '-'))
+			return append_field_cal(ccli, tep, list,
+						argv[1], argv[2], argv[word], match);
+
 		if (strchr(p, '.'))
-			return append_field_ts(ccli, tep, list, argv[word]);
+			return append_field_ts(ccli, tep, list, argv[word], match);
 
-		argv[word][p - match] = '\0';
+		len = p - match;
+		prefix = argv[word];
+		prefix[len + 1] = '\0';
+		prefix[len] = '=';
 
-		/* Can only be one of the previous events */
-		p = strchr(argv[1], '.');
-		if (!p) {
-			ccli_printf(ccli, "# %s needs a field\n", argv[1]);
-			ccli_line_refresh(ccli);
-			return 0;
-		}
-		*p = '\0';
-		event1 = find_event(tep, argv[1]);
-		if (!event1) {
-			ccli_printf(ccli, "\n# Event %s not found\n", argv[1]);
-			ccli_line_refresh(ccli);
-			return 0;
-		}
-		p = strchr(argv[2], '.');
-		if (!p) {
-			ccli_printf(ccli, "\n# %s needs a field\n", argv[2]);
-			ccli_line_refresh(ccli);
-			return 0;
-		}
-		*p = '\0';
-		event2 = find_event(tep, argv[2]);
-		if (!event2) {
-			ccli_printf(ccli, "\n# Event %s not found\n", argv[2]);
-			ccli_line_refresh(ccli);
-			return 0;
-		}
-
-		ccli_list_add_printf(ccli, list, &cnt, "%s=%s/%s", argv[word],
-				     event1->system, event1->name);
-		ret = ccli_list_add_printf(ccli, list, &cnt, "%s=%s/%s",
-					   argv[word], event2->system, event2->name);
+		ret = synth_event_match(ccli, list, &cnt, tep, prefix, argv[1], argv[2]);
 		match[strlen(match)] = '.';
 
+		if (ret < 0)
+			ccli_list_free(ccli, list, cnt);
 		return ret;
 	}
 	printf("\neprobe word=%d match=%s\n", word, match);