lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <a6eef00b11a018ed3b7d1cb90fe990be38704ecf.1445530672.git.tom.zanussi@linux.intel.com>
Date:	Thu, 22 Oct 2015 13:14:14 -0500
From:	Tom Zanussi <tom.zanussi@...ux.intel.com>
To:	rostedt@...dmis.org
Cc:	daniel.wagner@...-carit.de, masami.hiramatsu.pt@...achi.com,
	namhyung@...nel.org, josh@...htriplett.org, andi@...stfloor.org,
	mathieu.desnoyers@...icios.com, peterz@...radead.org,
	linux-kernel@...r.kernel.org,
	Tom Zanussi <tom.zanussi@...ux.intel.com>
Subject: [PATCH v11 10/28] tracing: Add hist trigger support for multiple values ('vals=' param)

Allow users to specify trace event fields to use in aggregated sums
via a new 'vals=' keyword.  Before this addition, the only aggregated
sum supported was the implied value 'hitcount'.  With this addition,
'hitcount' is also supported as an explicit value field, as is any
numeric trace event field.

This expands the hist trigger syntax from this:

  # echo hist:keys=xxx [ if filter] > event/trigger

to this:

  # echo hist:keys=xxx:vals=yyy [ if filter] > event/trigger

Signed-off-by: Tom Zanussi <tom.zanussi@...ux.intel.com>
Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
---
 kernel/trace/trace.c             | 12 ++++---
 kernel/trace/trace_events_hist.c | 75 +++++++++++++++++++++++++++++++++++++++-
 2 files changed, 81 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 6d5870b..98817d5 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3799,14 +3799,16 @@ static const char readme_msg[] =
 #ifdef CONFIG_HIST_TRIGGERS
 	"      hist trigger\t- If set, event hits are aggregated into a hash table\n"
 	"\t    Format: hist:keys=<field1>\n"
+	"\t            [:values=<field1[,field2,...]]\n"
 	"\t            [:size=#entries]\n"
 	"\t            [if <filter>]\n\n"
 	"\t    When a matching event is hit, an entry is added to a hash\n"
-	"\t    table using the key named, and the value of a sum called\n"
-	"\t    'hitcount' is incremented.  Keys correspond to fields in the\n"
-	"\t    event's format description.  Keys can be any field.  The\n"
-	"\t    'size' parameter can be  used to specify more or fewer than\n"
-	"\t    the default 2048 entries for the hashtable size.\n\n"
+	"\t    table using the key(s) and value(s) named, and the value of a\n"
+	"\t    sum called 'hitcount' is incremented.  Keys and values\n"
+	"\t    correspond to fields in the event's format description.  Keys\n"
+	"\t    can be any field.  Values must correspond to numeric fields.\n"
+	"\t    The 'size' parameter can be  used to specify more or fewer\n"
+	"\t    than the default 2048 entries for the hashtable size.\n\n"
 	"\t    Reading the 'hist' file for the event will dump the hash\n"
 	"\t    table in its entirety to stdout."
 #endif
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 376626b..efa62b3 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -75,6 +75,7 @@ enum hist_field_flags {
 
 struct hist_trigger_attrs {
 	char		*keys_str;
+	char		*vals_str;
 	unsigned int	map_bits;
 };
 
@@ -155,6 +156,7 @@ static int parse_map_size(char *str)
 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
 {
 	kfree(attrs->keys_str);
+	kfree(attrs->vals_str);
 	kfree(attrs);
 }
 
@@ -173,6 +175,10 @@ static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
 		if (!strncmp(str, "keys", strlen("keys")) ||
 		    !strncmp(str, "key", strlen("key")))
 			attrs->keys_str = kstrdup(str, GFP_KERNEL);
+		else if (!strncmp(str, "values", strlen("values")) ||
+			 !strncmp(str, "vals", strlen("vals")) ||
+			 !strncmp(str, "val", strlen("val")))
+			attrs->vals_str = kstrdup(str, GFP_KERNEL);
 		else if (!strncmp(str, "size", strlen("size"))) {
 			int map_bits = parse_map_size(str);
 
@@ -256,13 +262,66 @@ static int create_hitcount_val(struct hist_trigger_data *hist_data)
 	return 0;
 }
 
+static int create_val_field(struct hist_trigger_data *hist_data,
+			    unsigned int val_idx,
+			    struct trace_event_file *file,
+			    char *field_str)
+{
+	struct ftrace_event_field *field = NULL;
+	unsigned long flags = 0;
+	int ret = 0;
+
+	field = trace_find_event_field(file->event_call, field_str);
+	if (!field) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	hist_data->fields[val_idx] = create_hist_field(field, flags);
+	if (!hist_data->fields[val_idx]) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	hist_data->n_vals++;
+ out:
+	return ret;
+}
+
 static int create_val_fields(struct hist_trigger_data *hist_data,
 			     struct trace_event_file *file)
 {
+	unsigned int vals_max = TRACING_MAP_FIELDS_MAX - TRACING_MAP_KEYS_MAX;
+	char *fields_str, *field_str;
+	unsigned int i, j;
 	int ret;
 
 	ret = create_hitcount_val(hist_data);
+	if (ret)
+		goto out;
 
+	fields_str = hist_data->attrs->vals_str;
+	if (!fields_str)
+		goto out;
+
+	strsep(&fields_str, "=");
+	if (!fields_str)
+		goto out;
+
+	vals_max = TRACING_MAP_FIELDS_MAX - TRACING_MAP_KEYS_MAX;
+
+	for (i = 0, j = 1; i < vals_max; i++) {
+		field_str = strsep(&fields_str, ",");
+		if (!field_str)
+			break;
+		if (!strcmp(field_str, "hitcount"))
+			continue;
+		ret = create_val_field(hist_data, j++, file, field_str);
+		if (ret)
+			goto out;
+	}
+	if (fields_str)
+		ret = -EINVAL;
+ out:
 	return ret;
 }
 
@@ -534,6 +593,12 @@ hist_trigger_entry_print(struct seq_file *m,
 	seq_printf(m, " hitcount: %10llu",
 		   tracing_map_read_sum(elt, HITCOUNT_IDX));
 
+	for (i = 1; i < hist_data->n_vals; i++) {
+		seq_printf(m, "  %s: %10llu",
+			   hist_data->fields[i]->field->name,
+			   tracing_map_read_sum(elt, i));
+	}
+
 	seq_puts(m, "\n");
 }
 
@@ -641,7 +706,15 @@ static int event_hist_trigger_print(struct seq_file *m,
 	}
 
 	seq_puts(m, ":vals=");
-	seq_puts(m, "hitcount");
+
+	for (i = 0; i < hist_data->n_vals; i++) {
+		if (i == 0)
+			seq_puts(m, "hitcount");
+		else {
+			seq_puts(m, ",");
+			hist_field_print(m, hist_data->fields[i]);
+		}
+	}
 
 	seq_puts(m, ":sort=");
 	seq_puts(m, "hitcount");
-- 
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ