[PATCH perf/core 5/8] perf probe: Allow to use filter on --del command

[Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>]

This makes perf-probe --del option to accept filter rules
not only simple glob pattern. This simplifies the code and
improve the flexibility.

E.g. if we remove 2 different pattern events, we need 2
     -d options.
  ----
  # ./perf probe -d vfs\* -d malloc
  Removed event: probe_libc:malloc
  Removed event: probe:vfs_read
  ----

  This allows you to joint the 2 patterns with '|'.

  ----
  # ./perf probe -d 'vfs*|malloc'
  Removed event: probe:vfs_read
  Removed event: probe_libc:malloc
  ----

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
---
 tools/perf/builtin-probe.c    |   16 +++----
 tools/perf/util/probe-event.c |   89 +++++++++++------------------------------
 tools/perf/util/probe-event.h |    2 -
 tools/perf/util/strfilter.c   |   66 ++++++++++++++++++++++++++++++
 tools/perf/util/strfilter.h   |    9 ++++
 5 files changed, 106 insertions(+), 76 deletions(-)

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index feca316..1f41b4e 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -55,12 +55,12 @@ static struct {
 	bool show_ext_vars;
 	bool show_funcs;
 	bool mod_events;
+	bool del_events;
 	bool uprobes;
 	bool quiet;
 	bool target_used;
 	int nevents;
 	struct perf_probe_event events[MAX_PROBES];
-	struct strlist *dellist;
 	struct line_range line_range;
 	char *target;
 	int max_probe_points;
@@ -195,10 +195,8 @@ static int opt_del_probe_event(const struct option *opt __maybe_unused,
 			       const char *str, int unset __maybe_unused)
 {
 	if (str) {
-		params.mod_events = true;
-		if (!params.dellist)
-			params.dellist = strlist__new(true, NULL);
-		strlist__add(params.dellist, str);
+		params.del_events = true;
+		return params_add_filter(str);
 	}
 	return 0;
 }
@@ -313,8 +311,6 @@ static void cleanup_params(void)
 
 	for (i = 0; i < params.nevents; i++)
 		clear_perf_probe_event(params.events + i);
-	if (params.dellist)
-		strlist__delete(params.dellist);
 	line_range__clear(&params.line_range);
 	free(params.target);
 	if (params.filter)
@@ -454,7 +450,7 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
 	if (params.max_probe_points == 0)
 		params.max_probe_points = MAX_PROBES;
 
-	if ((!params.nevents && !params.dellist && !params.list_events &&
+	if ((!params.nevents && !params.del_events && !params.list_events &&
 	     !params.show_lines && !params.show_funcs))
 		usage_with_options(probe_usage, options);
 
@@ -514,8 +510,8 @@ __cmd_probe(int argc, const char **argv, const char *prefix __maybe_unused)
 	}
 #endif
 
-	if (params.dellist) {
-		ret = del_perf_probe_events(params.dellist);
+	if (params.del_events) {
+		ret = del_perf_probe_events(params.filter);
 		if (ret < 0) {
 			pr_err_with_code("  Error: Failed to delete events.", ret);
 			return ret;
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index 38bb282..2b08992 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2701,40 +2701,36 @@ error:
 	return ret;
 }
 
-static int del_trace_probe_event(int fd, const char *buf,
-						  struct strlist *namelist)
+static int del_trace_probe_events(int fd, struct strfilter *filter,
+				  struct strlist *namelist)
 {
-	struct str_node *ent, *n;
+	struct str_node *ent;
+	const char *p;
 	int ret = -1;
 
-	if (strpbrk(buf, "*?")) { /* Glob-exp */
-		strlist__for_each_safe(ent, n, namelist)
-			if (strglobmatch(ent->s, buf)) {
-				ret = __del_trace_probe_event(fd, ent);
-				if (ret < 0)
-					break;
-				strlist__remove(namelist, ent);
-			}
-	} else {
-		ent = strlist__find(namelist, buf);
-		if (ent) {
+	if (!namelist)
+		return -ENOENT;
+
+	strlist__for_each(ent, namelist) {
+		p = strchr(ent->s, ':');
+		if ((p && strfilter__compare(filter, p + 1)) ||
+		    strfilter__compare(filter, ent->s)) {
 			ret = __del_trace_probe_event(fd, ent);
-			if (ret >= 0)
-				strlist__remove(namelist, ent);
+			if (ret < 0)
+				break;
 		}
 	}
 
 	return ret;
 }
 
-int del_perf_probe_events(struct strlist *dellist)
+int del_perf_probe_events(struct strfilter *filter)
 {
-	int ret = -1, ret2, ufd = -1, kfd = -1;
-	char buf[128];
-	const char *group, *event;
-	char *p, *str;
-	struct str_node *ent;
+	int ret = 0, ufd = -1, kfd = -1;
 	struct strlist *namelist = NULL, *unamelist = NULL;
+	char *str = strfilter__string(filter);
+
+	pr_debug("Filter: \'%s\'\n", str);
 
 	/* Get current event names */
 	kfd = open_kprobe_events(true);
@@ -2747,53 +2743,15 @@ int del_perf_probe_events(struct strlist *dellist)
 
 	if (kfd < 0 && ufd < 0) {
 		print_both_open_warning(kfd, ufd);
+		ret = kfd;
 		goto error;
 	}
 
-	if (namelist == NULL && unamelist == NULL) {
-		ret = -ENOENT;
-		goto error;
-	}
-
-	strlist__for_each(ent, dellist) {
-		str = strdup(ent->s);
-		if (str == NULL) {
-			ret = -ENOMEM;
-			goto error;
-		}
-		pr_debug("Parsing: %s\n", str);
-		p = strchr(str, ':');
-		if (p) {
-			group = str;
-			*p = '\0';
-			event = p + 1;
-		} else {
-			group = "*";
-			event = str;
-		}
-
-		ret = e_snprintf(buf, 128, "%s:%s", group, event);
-		if (ret < 0) {
-			pr_err("Failed to copy event.");
-			free(str);
-			goto error;
-		}
-
-		pr_debug("Group: %s, Event: %s\n", group, event);
-
-		ret = ret2 = -ENOENT;
-		if (namelist)
-			ret = del_trace_probe_event(kfd, buf, namelist);
-
-		if (unamelist)
-			ret2 = del_trace_probe_event(ufd, buf, unamelist);
-
-		/* Since we can remove probes which already removed, no error  */
-		if (ret != 0 && ret2 != 0)
-			pr_debug("Event \"%s\" does not exist.\n", buf);
+	ret = del_trace_probe_events(kfd, filter, namelist);
+	if (del_trace_probe_events(ufd, filter, unamelist) < 0 && ret < 0) {
+		pr_debug("\"%s\" does not hit any event.\n", str);
+		/* Note that this is silently ignored */
 		ret = 0;
-
-		free(str);
 	}
 
 error:
@@ -2806,6 +2764,7 @@ error:
 		strlist__delete(unamelist);
 		close(ufd);
 	}
+	free(str);
 
 	return ret;
 }
diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h
index 819e825..027356f 100644
--- a/tools/perf/util/probe-event.h
+++ b/tools/perf/util/probe-event.h
@@ -126,7 +126,7 @@ extern const char *kernel_get_module_path(const char *module);
 
 extern int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
 				 int max_probe_points, bool force_add);
-extern int del_perf_probe_events(struct strlist *dellist);
+extern int del_perf_probe_events(struct strfilter *filter);
 extern int show_perf_probe_events(struct strfilter *filter);
 extern int show_line_range(struct line_range *lr, const char *module,
 			   bool user);
diff --git a/tools/perf/util/strfilter.c b/tools/perf/util/strfilter.c
index cd659e6..9206618 100644
--- a/tools/perf/util/strfilter.c
+++ b/tools/perf/util/strfilter.c
@@ -231,3 +231,69 @@ bool strfilter__compare(struct strfilter *filter, const char *str)
 		return false;
 	return strfilter_node__compare(filter->root, str);
 }
+
+static int strfilter_node__sprint(struct strfilter_node *node, char *buf);
+
+/* sprint node in parenthesis if needed */
+static int strfilter_node__sprint_pt(struct strfilter_node *node, char *buf)
+{
+	int len;
+	int pt = node->r ? 2 : 0;	/* don't need to check node->l */
+
+	if (buf && pt)
+		*buf++ = '(';
+	len = strfilter_node__sprint(node, buf);
+	if (len < 0)
+		return len;
+	if (buf && pt)
+		*(buf + len) = ')';
+	return len + pt;
+}
+
+static int strfilter_node__sprint(struct strfilter_node *node, char *buf)
+{
+	int len = 0, rlen;
+
+	if (!node || !node->p)
+		return -EINVAL;
+
+	switch (*node->p) {
+	case '|':
+	case '&':
+		len = strfilter_node__sprint_pt(node->l, buf);
+		if (len < 0)
+			return len;
+	case '!':
+		if (buf) {
+			*(buf + len++) = *node->p;
+			buf += len;
+		} else
+			len++;
+		rlen = strfilter_node__sprint_pt(node->r, buf);
+		if (rlen < 0)
+			return rlen;
+		len += rlen;
+		break;
+	default:
+		len = strlen(node->p);
+		if (buf)
+			strcpy(buf, node->p);
+	}
+
+	return len;
+}
+
+char *strfilter__string(struct strfilter *filter)
+{
+	int len;
+	char *ret = NULL;
+
+	len = strfilter_node__sprint(filter->root, NULL);
+	if (len < 0)
+		return NULL;
+
+	ret = malloc(len + 1);
+	strfilter_node__sprint(filter->root, ret);
+
+	return ret;
+}
diff --git a/tools/perf/util/strfilter.h b/tools/perf/util/strfilter.h
index c81ff97..d0b772c 100644
--- a/tools/perf/util/strfilter.h
+++ b/tools/perf/util/strfilter.h
@@ -58,4 +58,13 @@ bool strfilter__compare(struct strfilter *filter, const char *str);
  */
 void strfilter__delete(struct strfilter *filter);
 
+/**
+ * strfilter__string - Reconstruct a rule string from filter
+ * @filter: String filter to reconstruct
+ *
+ * Reconstruct a rule string from @filter. This will be good for
+ * debug messages. Note that returning string must be freed afterward.
+ */
+char *strfilter__string(struct strfilter *filter);
+
 #endif