[PATCH 0/6] [GIT PULL] tracing: more updates

[PATCH 0/6] [GIT PULL] tracing: more updates

[Steven Rostedt]

Ingo,

Please pull the latest tip/tracing/core3 tree, which can be found at:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
tip/tracing/core3


Steven Rostedt (3):
      tracing: move tgid out of generic entry and into userstack
      tracing: add lock depth to entries
      tracing: consolidate code between trace_output.c and trace_function_graph.c

jolsa@redhat.com (3):
      tracing: create generic trace parser
      tracing: trace parser support for set_event
      tracing: trace parser support for function and graph

----
 include/linux/ftrace_event.h         |    2 +-
 kernel/trace/ftrace.c                |  150 +++++++++-------------------------
 kernel/trace/trace.c                 |  117 +++++++++++++++++++++++++-
 kernel/trace/trace.h                 |   36 ++++++++
 kernel/trace/trace_events.c          |   64 ++++-----------
 kernel/trace/trace_functions_graph.c |   26 ++-----
 kernel/trace/trace_output.c          |   42 ++++++++--
 kernel/trace/trace_output.h          |    2 +
 8 files changed, 246 insertions(+), 193 deletions(-)
-- 

[PATCH 1/6] tracing: move tgid out of generic entry and into userstack

[Steven Rostedt]

[-- Attachment #1: 0001-tracing-move-tgid-out-of-generic-entry-and-into-user.patch --]
[-- Type: text/plain, Size: 3425 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

The userstack trace required the recording of the tgid entry.
Unfortunately, it was added to the generic entry where it wasted
4 bytes of every entry and was only used by one entry.

This patch moves it out of the generic field and moves it into the
only user (userstack_entry).

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/linux/ftrace_event.h |    1 -
 kernel/trace/trace.c         |    2 +-
 kernel/trace/trace.h         |    1 +
 kernel/trace/trace_events.c  |    5 +----
 kernel/trace/trace_output.c  |    2 +-
 5 files changed, 4 insertions(+), 7 deletions(-)

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 23f7179..06c795b 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -34,7 +34,6 @@ struct trace_entry {
 	unsigned char		flags;
 	unsigned char		preempt_count;
 	int			pid;
-	int			tgid;
 };
 
 #define FTRACE_MAX_EVENT						\
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c75dee..1a37da2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -886,7 +886,6 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 
 	entry->preempt_count		= pc & 0xff;
 	entry->pid			= (tsk) ? tsk->pid : 0;
-	entry->tgid			= (tsk) ? tsk->tgid : 0;
 	entry->flags =
 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 		(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1068,6 +1067,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
 		return;
 	entry	= ring_buffer_event_data(event);
 
+	entry->tgid		= current->tgid;
 	memset(&entry->caller, 0, sizeof(entry->caller));
 
 	trace.nr_entries	= 0;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index acaa680..b69697b 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -101,6 +101,7 @@ struct stack_entry {
 
 struct userstack_entry {
 	struct trace_entry	ent;
+	unsigned int		tgid;
 	unsigned long		caller[FTRACE_STACK_ENTRIES];
 };
 
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 78b1ed2..28d9202 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -86,7 +86,6 @@ int trace_define_common_fields(struct ftrace_event_call *call)
 	__common_field(unsigned char, flags);
 	__common_field(unsigned char, preempt_count);
 	__common_field(int, pid);
-	__common_field(int, tgid);
 
 	return ret;
 }
@@ -572,13 +571,11 @@ static int trace_write_header(struct trace_seq *s)
 				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
 				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
 				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
-				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
 				"\n",
 				FIELD(unsigned short, type),
 				FIELD(unsigned char, flags),
 				FIELD(unsigned char, preempt_count),
-				FIELD(int, pid),
-				FIELD(int, tgid));
+				FIELD(int, pid));
 }
 
 static ssize_t
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index e0c2545..be34a6a 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -407,7 +407,7 @@ seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
 		 * since individual threads might have already quit!
 		 */
 		rcu_read_lock();
-		task = find_task_by_vpid(entry->ent.tgid);
+		task = find_task_by_vpid(entry->tgid);
 		if (task)
 			mm = get_task_mm(task);
 		rcu_read_unlock();
-- 
1.6.3.3

-- 

[PATCH 2/6] tracing: add lock depth to entries

[Steven Rostedt]

[-- Attachment #1: 0002-tracing-add-lock-depth-to-entries.patch --]
[-- Type: text/plain, Size: 7062 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

This patch adds the lock depth of the big kernel lock to the generic
entry header. This way we can see the depth of the lock and help
in removing the BKL.

Example:

 #                  _------=> CPU#
 #                 / _-----=> irqs-off
 #                | / _----=> need-resched
 #                || / _---=> hardirq/softirq
 #                ||| / _--=> preempt-depth
 #                |||| /_--=> lock-depth
 #                |||||/     delay
 #  cmd     pid   |||||| time  |   caller
 #     \   /      ||||||   \   |   /
   <idle>-0       2.N..3 5902255250us+: lock_acquire: read rcu_read_lock
   <idle>-0       2.N..3 5902255253us+: lock_release: rcu_read_lock
   <idle>-0       2dN..3 5902255257us+: lock_acquire: xtime_lock
   <idle>-0       2dN..4 5902255259us : lock_acquire: clocksource_lock
   <idle>-0       2dN..4 5902255261us+: lock_release: clocksource_lock

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/linux/ftrace_event.h         |    1 +
 kernel/trace/trace.c                 |    9 +++++----
 kernel/trace/trace_events.c          |    5 ++++-
 kernel/trace/trace_functions_graph.c |   16 ++++++++++++----
 kernel/trace/trace_output.c          |   10 +++++++++-
 5 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 06c795b..0608b0f 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -34,6 +34,7 @@ struct trace_entry {
 	unsigned char		flags;
 	unsigned char		preempt_count;
 	int			pid;
+	int			lock_depth;
 };
 
 #define FTRACE_MAX_EVENT						\
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1a37da2..3b91828 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -886,6 +886,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 
 	entry->preempt_count		= pc & 0xff;
 	entry->pid			= (tsk) ? tsk->pid : 0;
+	entry->lock_depth		= (tsk) ? tsk->lock_depth : 0;
 	entry->flags =
 #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
 		(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
@@ -1530,10 +1531,10 @@ static void print_lat_help_header(struct seq_file *m)
 	seq_puts(m, "#                | / _----=> need-resched    \n");
 	seq_puts(m, "#                || / _---=> hardirq/softirq \n");
 	seq_puts(m, "#                ||| / _--=> preempt-depth   \n");
-	seq_puts(m, "#                |||| /                      \n");
-	seq_puts(m, "#                |||||     delay             \n");
-	seq_puts(m, "#  cmd     pid   ||||| time  |   caller      \n");
-	seq_puts(m, "#     \\   /      |||||   \\   |   /           \n");
+	seq_puts(m, "#                |||| /_--=> lock-depth       \n");
+	seq_puts(m, "#                |||||/     delay             \n");
+	seq_puts(m, "#  cmd     pid   |||||| time  |   caller      \n");
+	seq_puts(m, "#     \\   /      ||||||   \\   |   /           \n");
 }
 
 static void print_func_help_header(struct seq_file *m)
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 28d9202..975f324 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -86,6 +86,7 @@ int trace_define_common_fields(struct ftrace_event_call *call)
 	__common_field(unsigned char, flags);
 	__common_field(unsigned char, preempt_count);
 	__common_field(int, pid);
+	__common_field(int, lock_depth);
 
 	return ret;
 }
@@ -571,11 +572,13 @@ static int trace_write_header(struct trace_seq *s)
 				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
 				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
 				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
+				"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
 				"\n",
 				FIELD(unsigned short, type),
 				FIELD(unsigned char, flags),
 				FIELD(unsigned char, preempt_count),
-				FIELD(int, pid));
+				FIELD(int, pid),
+				FIELD(int, lock_depth));
 }
 
 static ssize_t
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index ee791a9..48af493 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -368,6 +368,7 @@ static enum print_line_t
 print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
 	int hardirq, softirq;
+	int ret;
 
 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
@@ -382,6 +383,13 @@ print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 				hardirq ? 'h' : softirq ? 's' : '.'))
 		return 0;
 
+	if (entry->lock_depth < 0)
+		ret = trace_seq_putc(s, '.');
+	else
+		ret = trace_seq_printf(s, "%d", entry->lock_depth);
+	if (!ret)
+		return 0;
+
 	if (entry->preempt_count)
 		return trace_seq_printf(s, "%x", entry->preempt_count);
 	return trace_seq_puts(s, ".");
@@ -1001,8 +1009,8 @@ static void print_lat_header(struct seq_file *s)
 	seq_printf(s, "#%.*s / _----=> need-resched    \n", size, spaces);
 	seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces);
 	seq_printf(s, "#%.*s|| / _--=> preempt-depth   \n", size, spaces);
-	seq_printf(s, "#%.*s||| /                      \n", size, spaces);
-	seq_printf(s, "#%.*s||||                       \n", size, spaces);
+	seq_printf(s, "#%.*s||| / _-=> lock-depth      \n", size, spaces);
+	seq_printf(s, "#%.*s|||| /                     \n", size, spaces);
 }
 
 static void print_graph_headers(struct seq_file *s)
@@ -1021,7 +1029,7 @@ static void print_graph_headers(struct seq_file *s)
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
 		seq_printf(s, "  TASK/PID       ");
 	if (lat)
-		seq_printf(s, "||||");
+		seq_printf(s, "|||||");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
 		seq_printf(s, "  DURATION   ");
 	seq_printf(s, "               FUNCTION CALLS\n");
@@ -1035,7 +1043,7 @@ static void print_graph_headers(struct seq_file *s)
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
 		seq_printf(s, "   |    |        ");
 	if (lat)
-		seq_printf(s, "||||");
+		seq_printf(s, "|||||");
 	if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
 		seq_printf(s, "   |   |      ");
 	seq_printf(s, "               |   |   |   |\n");
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index be34a6a..29a370a 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -465,6 +465,7 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 {
 	int hardirq, softirq;
 	char comm[TASK_COMM_LEN];
+	int ret;
 
 	trace_find_cmdline(entry->pid, comm);
 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
@@ -481,9 +482,16 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 				hardirq ? 'h' : softirq ? 's' : '.'))
 		return 0;
 
+	if (entry->lock_depth < 0)
+		ret = trace_seq_putc(s, '.');
+	else
+		ret = trace_seq_printf(s, "%d", entry->lock_depth);
+	if (!ret)
+		return 0;
+
 	if (entry->preempt_count)
 		return trace_seq_printf(s, "%x", entry->preempt_count);
-	return trace_seq_puts(s, ".");
+	return trace_seq_putc(s, '.');
 }
 
 static unsigned long preempt_mark_thresh = 100;
-- 
1.6.3.3

-- 

[PATCH 3/6] tracing: consolidate code between trace_output.c and trace_function_graph.c

[Steven Rostedt]

[-- Attachment #1: 0003-tracing-consolidate-code-between-trace_output.c-and-.patch --]
[-- Type: text/plain, Size: 3989 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

Both trace_output.c and trace_function_graph.c do basically the same
thing to handle the printing of the latency-format. This patch moves
the code into one function that both can use.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace_functions_graph.c |   26 ++------------------------
 kernel/trace/trace_output.c          |   30 ++++++++++++++++++++++++------
 kernel/trace/trace_output.h          |    2 ++
 3 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 48af493..61f1667 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -367,32 +367,10 @@ print_graph_proc(struct trace_seq *s, pid_t pid)
 static enum print_line_t
 print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
-	int hardirq, softirq;
-	int ret;
-
-	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
-	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
-
-	if (!trace_seq_printf(s, " %c%c%c",
-			      (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
-				(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
-				  'X' : '.',
-			      (entry->flags & TRACE_FLAG_NEED_RESCHED) ?
-				'N' : '.',
-			      (hardirq && softirq) ? 'H' :
-				hardirq ? 'h' : softirq ? 's' : '.'))
-		return 0;
-
-	if (entry->lock_depth < 0)
-		ret = trace_seq_putc(s, '.');
-	else
-		ret = trace_seq_printf(s, "%d", entry->lock_depth);
-	if (!ret)
+	if (!trace_seq_putc(s, ' '))
 		return 0;
 
-	if (entry->preempt_count)
-		return trace_seq_printf(s, "%x", entry->preempt_count);
-	return trace_seq_puts(s, ".");
+	return trace_print_lat_fmt(s, entry);
 }
 
 /* If the pid changed since the last trace, output this event */
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 29a370a..f572f44 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -460,19 +460,23 @@ seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
 	return ret;
 }
 
-static int
-lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+/**
+ * trace_print_lat_fmt - print the irq, preempt and lockdep fields
+ * @s: trace seq struct to write to
+ * @entry: The trace entry field from the ring buffer
+ *
+ * Prints the generic fields of irqs off, in hard or softirq, preempt
+ * count and lock depth.
+ */
+int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 {
 	int hardirq, softirq;
-	char comm[TASK_COMM_LEN];
 	int ret;
 
-	trace_find_cmdline(entry->pid, comm);
 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
 	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
 
-	if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c",
-			      comm, entry->pid, cpu,
+	if (!trace_seq_printf(s, "%c%c%c",
 			      (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 				(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
 				  'X' : '.',
@@ -494,6 +498,20 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
 	return trace_seq_putc(s, '.');
 }
 
+static int
+lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+{
+	char comm[TASK_COMM_LEN];
+
+	trace_find_cmdline(entry->pid, comm);
+
+	if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
+			      comm, entry->pid, cpu))
+		return 0;
+
+	return trace_print_lat_fmt(s, entry);
+}
+
 static unsigned long preempt_mark_thresh = 100;
 
 static int
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index d38bec4..9d91c72 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -26,6 +26,8 @@ extern struct trace_event *ftrace_find_event(int type);
 
 extern enum print_line_t trace_nop_print(struct trace_iterator *iter,
 					 int flags);
+extern int
+trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry);
 
 /* used by module unregistering */
 extern int __unregister_ftrace_event(struct trace_event *event);
-- 
1.6.3.3

-- 

[PATCH 4/6] tracing: create generic trace parser

[Steven Rostedt]

[-- Attachment #1: 0004-tracing-create-generic-trace-parser.patch --]
[-- Type: text/plain, Size: 4250 bytes --]

From: jolsa@redhat.com <jolsa@redhat.com>

Create a "trace_parser" that can parse the user space input for
separate words.

struct trace_parser is the descriptor.

Generic "trace_get_user" function that can be a helper to read multiple
words passed in by user space.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-2-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace.c |  106 ++++++++++++++++++++++++++++++++++++++++++++++++++
 kernel/trace/trace.h |   35 ++++++++++++++++
 2 files changed, 141 insertions(+), 0 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 3b91828..45c3f03 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -339,6 +339,112 @@ static struct {
 
 int trace_clock_id;
 
+/*
+ * trace_parser_get_init - gets the buffer for trace parser
+ */
+int trace_parser_get_init(struct trace_parser *parser, int size)
+{
+	memset(parser, 0, sizeof(*parser));
+
+	parser->buffer = kmalloc(size, GFP_KERNEL);
+	if (!parser->buffer)
+		return 1;
+
+	parser->size = size;
+	return 0;
+}
+
+/*
+ * trace_parser_put - frees the buffer for trace parser
+ */
+void trace_parser_put(struct trace_parser *parser)
+{
+	kfree(parser->buffer);
+}
+
+/*
+ * trace_get_user - reads the user input string separated by  space
+ * (matched by isspace(ch))
+ *
+ * For each string found the 'struct trace_parser' is updated,
+ * and the function returns.
+ *
+ * Returns number of bytes read.
+ *
+ * See kernel/trace/trace.h for 'struct trace_parser' details.
+ */
+int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+	size_t cnt, loff_t *ppos)
+{
+	char ch;
+	size_t read = 0;
+	ssize_t ret;
+
+	if (!*ppos)
+		trace_parser_clear(parser);
+
+	ret = get_user(ch, ubuf++);
+	if (ret)
+		goto out;
+
+	read++;
+	cnt--;
+
+	/*
+	 * The parser is not finished with the last write,
+	 * continue reading the user input without skipping spaces.
+	 */
+	if (!parser->cont) {
+		/* skip white space */
+		while (cnt && isspace(ch)) {
+			ret = get_user(ch, ubuf++);
+			if (ret)
+				goto out;
+			read++;
+			cnt--;
+		}
+
+		/* only spaces were written */
+		if (isspace(ch)) {
+			*ppos += read;
+			ret = read;
+			goto out;
+		}
+
+		parser->idx = 0;
+	}
+
+	/* read the non-space input */
+	while (cnt && !isspace(ch)) {
+		if (parser->idx < parser->size)
+			parser->buffer[parser->idx++] = ch;
+		else {
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = get_user(ch, ubuf++);
+		if (ret)
+			goto out;
+		read++;
+		cnt--;
+	}
+
+	/* We either got finished input or we have to wait for another call. */
+	if (isspace(ch)) {
+		parser->buffer[parser->idx] = 0;
+		parser->cont = false;
+	} else {
+		parser->cont = true;
+		parser->buffer[parser->idx++] = ch;
+	}
+
+	*ppos += read;
+	ret = read;
+
+out:
+	return ret;
+}
+
 ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
 {
 	int len;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b69697b..28247ce 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -616,6 +616,41 @@ static inline int ftrace_trace_task(struct task_struct *task)
 #endif
 
 /*
+ * struct trace_parser - servers for reading the user input separated by spaces
+ * @cont: set if the input is not complete - no final space char was found
+ * @buffer: holds the parsed user input
+ * @idx: user input lenght
+ * @size: buffer size
+ */
+struct trace_parser {
+	bool		cont;
+	char		*buffer;
+	unsigned	idx;
+	unsigned	size;
+};
+
+static inline bool trace_parser_loaded(struct trace_parser *parser)
+{
+	return (parser->idx != 0);
+}
+
+static inline bool trace_parser_cont(struct trace_parser *parser)
+{
+	return parser->cont;
+}
+
+static inline void trace_parser_clear(struct trace_parser *parser)
+{
+	parser->cont = false;
+	parser->idx = 0;
+}
+
+extern int trace_parser_get_init(struct trace_parser *parser, int size);
+extern void trace_parser_put(struct trace_parser *parser);
+extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+	size_t cnt, loff_t *ppos);
+
+/*
  * trace_iterator_flags is an enumeration that defines bit
  * positions into trace_flags that controls the output.
  *
-- 
1.6.3.3

-- 

[PATCH 5/6] tracing: trace parser support for set_event

[Steven Rostedt]

[-- Attachment #1: 0005-tracing-trace-parser-support-for-set_event.patch --]
[-- Type: text/plain, Size: 2212 bytes --]

From: jolsa@redhat.com <jolsa@redhat.com>

Convert the parsing of the file 'set_event' to use the generic
trace_praser 'trace_get_user' function.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-3-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace_events.c |   60 +++++++++---------------------------------
 1 files changed, 13 insertions(+), 47 deletions(-)

diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 975f324..f46d14c 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -230,11 +230,9 @@ static ssize_t
 ftrace_event_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos)
 {
+	struct trace_parser parser;
 	size_t read = 0;
-	int i, set = 1;
 	ssize_t ret;
-	char *buf;
-	char ch;
 
 	if (!cnt || cnt < 0)
 		return 0;
@@ -243,60 +241,28 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
 	if (ret < 0)
 		return ret;
 
-	ret = get_user(ch, ubuf++);
-	if (ret)
-		return ret;
-	read++;
-	cnt--;
-
-	/* skip white space */
-	while (cnt && isspace(ch)) {
-		ret = get_user(ch, ubuf++);
-		if (ret)
-			return ret;
-		read++;
-		cnt--;
-	}
-
-	/* Only white space found? */
-	if (isspace(ch)) {
-		file->f_pos += read;
-		ret = read;
-		return ret;
-	}
-
-	buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL);
-	if (!buf)
+	if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
 		return -ENOMEM;
 
-	if (cnt > EVENT_BUF_SIZE)
-		cnt = EVENT_BUF_SIZE;
+	read = trace_get_user(&parser, ubuf, cnt, ppos);
+
+	if (trace_parser_loaded((&parser))) {
+		int set = 1;
 
-	i = 0;
-	while (cnt && !isspace(ch)) {
-		if (!i && ch == '!')
+		if (*parser.buffer == '!')
 			set = 0;
-		else
-			buf[i++] = ch;
 
-		ret = get_user(ch, ubuf++);
+		parser.buffer[parser.idx] = 0;
+
+		ret = ftrace_set_clr_event(parser.buffer + !set, set);
 		if (ret)
-			goto out_free;
-		read++;
-		cnt--;
+			goto out_put;
 	}
-	buf[i] = 0;
-
-	file->f_pos += read;
-
-	ret = ftrace_set_clr_event(buf, set);
-	if (ret)
-		goto out_free;
 
 	ret = read;
 
- out_free:
-	kfree(buf);
+ out_put:
+	trace_parser_put(&parser);
 
 	return ret;
 }
-- 
1.6.3.3

-- 

[PATCH 6/6] tracing: trace parser support for function and graph

[Steven Rostedt]

[-- Attachment #1: 0006-tracing-trace-parser-support-for-function-and-graph.patch --]
[-- Type: text/plain, Size: 6605 bytes --]

From: jolsa@redhat.com <jolsa@redhat.com>

Convert the writing to 'set_graph_function', 'set_ftrace_filter'
and 'set_ftrace_notrace' to use the generic trace_parser
'trace_get_user' function.

Removed FTRACE_ITER_CONT flag, since it's not needed after this change.

Minor fix in set_graph_function display - g_show function.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-4-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/ftrace.c |  150 +++++++++++++------------------------------------
 1 files changed, 40 insertions(+), 110 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 8c804e2..8b23d56 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1323,11 +1323,10 @@ static int __init ftrace_dyn_table_alloc(unsigned long num_to_init)
 
 enum {
 	FTRACE_ITER_FILTER	= (1 << 0),
-	FTRACE_ITER_CONT	= (1 << 1),
-	FTRACE_ITER_NOTRACE	= (1 << 2),
-	FTRACE_ITER_FAILURES	= (1 << 3),
-	FTRACE_ITER_PRINTALL	= (1 << 4),
-	FTRACE_ITER_HASH	= (1 << 5),
+	FTRACE_ITER_NOTRACE	= (1 << 1),
+	FTRACE_ITER_FAILURES	= (1 << 2),
+	FTRACE_ITER_PRINTALL	= (1 << 3),
+	FTRACE_ITER_HASH	= (1 << 4),
 };
 
 #define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
@@ -1337,8 +1336,7 @@ struct ftrace_iterator {
 	int			hidx;
 	int			idx;
 	unsigned		flags;
-	unsigned char		buffer[FTRACE_BUFF_MAX+1];
-	unsigned		buffer_idx;
+	struct trace_parser	parser;
 };
 
 static void *
@@ -1604,6 +1602,11 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
 	if (!iter)
 		return -ENOMEM;
 
+	if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
+		kfree(iter);
+		return -ENOMEM;
+	}
+
 	mutex_lock(&ftrace_regex_lock);
 	if ((file->f_mode & FMODE_WRITE) &&
 	    (file->f_flags & O_TRUNC))
@@ -2196,9 +2199,8 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos, int enable)
 {
 	struct ftrace_iterator *iter;
-	char ch;
-	size_t read = 0;
-	ssize_t ret;
+	struct trace_parser *parser;
+	ssize_t ret, read;
 
 	if (!cnt || cnt < 0)
 		return 0;
@@ -2211,72 +2213,23 @@ ftrace_regex_write(struct file *file, const char __user *ubuf,
 	} else
 		iter = file->private_data;
 
-	if (!*ppos) {
-		iter->flags &= ~FTRACE_ITER_CONT;
-		iter->buffer_idx = 0;
-	}
-
-	ret = get_user(ch, ubuf++);
-	if (ret)
-		goto out;
-	read++;
-	cnt--;
-
-	/*
-	 * If the parser haven't finished with the last write,
-	 * continue reading the user input without skipping spaces.
-	 */
-	if (!(iter->flags & FTRACE_ITER_CONT)) {
-		/* skip white space */
-		while (cnt && isspace(ch)) {
-			ret = get_user(ch, ubuf++);
-			if (ret)
-				goto out;
-			read++;
-			cnt--;
-		}
+	parser = &iter->parser;
+	read = trace_get_user(parser, ubuf, cnt, ppos);
 
-		/* only spaces were written */
-		if (isspace(ch)) {
-			*ppos += read;
-			ret = read;
-			goto out;
-		}
-
-		iter->buffer_idx = 0;
-	}
-
-	while (cnt && !isspace(ch)) {
-		if (iter->buffer_idx < FTRACE_BUFF_MAX)
-			iter->buffer[iter->buffer_idx++] = ch;
-		else {
-			ret = -EINVAL;
-			goto out;
-		}
-		ret = get_user(ch, ubuf++);
+	if (trace_parser_loaded(parser) &&
+	    !trace_parser_cont(parser)) {
+		ret = ftrace_process_regex(parser->buffer,
+					   parser->idx, enable);
 		if (ret)
 			goto out;
-		read++;
-		cnt--;
-	}
 
-	if (isspace(ch)) {
-		iter->buffer[iter->buffer_idx] = 0;
-		ret = ftrace_process_regex(iter->buffer,
-					   iter->buffer_idx, enable);
-		if (ret)
-			goto out;
-		iter->buffer_idx = 0;
-	} else {
-		iter->flags |= FTRACE_ITER_CONT;
-		iter->buffer[iter->buffer_idx++] = ch;
+		trace_parser_clear(parser);
 	}
 
-	*ppos += read;
 	ret = read;
- out:
-	mutex_unlock(&ftrace_regex_lock);
 
+	mutex_unlock(&ftrace_regex_lock);
+out:
 	return ret;
 }
 
@@ -2381,6 +2334,7 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 {
 	struct seq_file *m = (struct seq_file *)file->private_data;
 	struct ftrace_iterator *iter;
+	struct trace_parser *parser;
 
 	mutex_lock(&ftrace_regex_lock);
 	if (file->f_mode & FMODE_READ) {
@@ -2390,9 +2344,10 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 	} else
 		iter = file->private_data;
 
-	if (iter->buffer_idx) {
-		iter->buffer[iter->buffer_idx] = 0;
-		ftrace_match_records(iter->buffer, iter->buffer_idx, enable);
+	parser = &iter->parser;
+	if (trace_parser_loaded(parser)) {
+		parser->buffer[parser->idx] = 0;
+		ftrace_match_records(parser->buffer, parser->idx, enable);
 	}
 
 	mutex_lock(&ftrace_lock);
@@ -2400,7 +2355,9 @@ ftrace_regex_release(struct inode *inode, struct file *file, int enable)
 		ftrace_run_update_code(FTRACE_ENABLE_CALLS);
 	mutex_unlock(&ftrace_lock);
 
+	trace_parser_put(parser);
 	kfree(iter);
+
 	mutex_unlock(&ftrace_regex_lock);
 	return 0;
 }
@@ -2499,7 +2456,7 @@ static int g_show(struct seq_file *m, void *v)
 		return 0;
 	}
 
-	seq_printf(m, "%pf\n", v);
+	seq_printf(m, "%pf\n", (void *)*ptr);
 
 	return 0;
 }
@@ -2602,12 +2559,10 @@ static ssize_t
 ftrace_graph_write(struct file *file, const char __user *ubuf,
 		   size_t cnt, loff_t *ppos)
 {
-	unsigned char buffer[FTRACE_BUFF_MAX+1];
+	struct trace_parser parser;
 	unsigned long *array;
 	size_t read = 0;
 	ssize_t ret;
-	int index = 0;
-	char ch;
 
 	if (!cnt || cnt < 0)
 		return 0;
@@ -2625,51 +2580,26 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
 	} else
 		array = file->private_data;
 
-	ret = get_user(ch, ubuf++);
-	if (ret)
+	if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
+		ret = -ENOMEM;
 		goto out;
-	read++;
-	cnt--;
-
-	/* skip white space */
-	while (cnt && isspace(ch)) {
-		ret = get_user(ch, ubuf++);
-		if (ret)
-			goto out;
-		read++;
-		cnt--;
 	}
 
-	if (isspace(ch)) {
-		*ppos += read;
-		ret = read;
-		goto out;
-	}
+	read = trace_get_user(&parser, ubuf, cnt, ppos);
 
-	while (cnt && !isspace(ch)) {
-		if (index < FTRACE_BUFF_MAX)
-			buffer[index++] = ch;
-		else {
-			ret = -EINVAL;
-			goto out;
-		}
-		ret = get_user(ch, ubuf++);
+	if (trace_parser_loaded((&parser))) {
+		parser.buffer[parser.idx] = 0;
+
+		/* we allow only one expression at a time */
+		ret = ftrace_set_func(array, &ftrace_graph_count,
+					parser.buffer);
 		if (ret)
 			goto out;
-		read++;
-		cnt--;
 	}
-	buffer[index] = 0;
-
-	/* we allow only one expression at a time */
-	ret = ftrace_set_func(array, &ftrace_graph_count, buffer);
-	if (ret)
-		goto out;
-
-	file->f_pos += read;
 
 	ret = read;
  out:
+	trace_parser_put(&parser);
 	mutex_unlock(&graph_lock);
 
 	return ret;
-- 
1.6.3.3

-- 

Re: [PATCH 4/6] tracing: create generic trace parser

[Steven Rostedt]

On Fri, 2009-09-11 at 15:31 -0400, Steven Rostedt wrote:
> plain text document attachment
> (0004-tracing-create-generic-trace-parser.patch)
> From: jolsa@redhat.com <jolsa@redhat.com>

Ug! I didn't realize that Jiri's email from line did not contain his
name. Thus his email became the author not his real name.

Ingo, do you want me to fix this? His SoB is correct though.

-- Steve

> 
> Create a "trace_parser" that can parse the user space input for
> separate words.
> 
> struct trace_parser is the descriptor.
> 
> Generic "trace_get_user" function that can be a helper to read multiple
> words passed in by user space.
> 
> Signed-off-by: Jiri Olsa <jolsa@redhat.com>
> LKML-Reference: <1252682969-3366-2-git-send-email-jolsa@redhat.com>
> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
> ---
>  kernel/trace/trace.c |  106 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  kernel/trace/trace.h |   35 ++++++++++++++++
>  2 files changed, 141 insertions(+), 0 deletions(-)
> 
> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
> index 3b91828..45c3f03 100644
> --- a/kernel/trace/trace.c
> +++ b/kernel/trace/trace.c
> @@ -339,6 +339,112 @@ static struct {
>  
>  int trace_clock_id;
>  
> +/*
> + * trace_parser_get_init - gets the buffer for trace parser
> + */
> +int trace_parser_get_init(struct trace_parser *parser, int size)
> +{
> +	memset(parser, 0, sizeof(*parser));
> +
> +	parser->buffer = kmalloc(size, GFP_KERNEL);
> +	if (!parser->buffer)
> +		return 1;
> +
> +	parser->size = size;
> +	return 0;
> +}
> +
> +/*
> + * trace_parser_put - frees the buffer for trace parser
> + */
> +void trace_parser_put(struct trace_parser *parser)
> +{
> +	kfree(parser->buffer);
> +}
> +
> +/*
> + * trace_get_user - reads the user input string separated by  space
> + * (matched by isspace(ch))
> + *
> + * For each string found the 'struct trace_parser' is updated,
> + * and the function returns.
> + *
> + * Returns number of bytes read.
> + *
> + * See kernel/trace/trace.h for 'struct trace_parser' details.
> + */
> +int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
> +	size_t cnt, loff_t *ppos)
> +{
> +	char ch;
> +	size_t read = 0;
> +	ssize_t ret;
> +
> +	if (!*ppos)
> +		trace_parser_clear(parser);
> +
> +	ret = get_user(ch, ubuf++);
> +	if (ret)
> +		goto out;
> +
> +	read++;
> +	cnt--;
> +
> +	/*
> +	 * The parser is not finished with the last write,
> +	 * continue reading the user input without skipping spaces.
> +	 */
> +	if (!parser->cont) {
> +		/* skip white space */
> +		while (cnt && isspace(ch)) {
> +			ret = get_user(ch, ubuf++);
> +			if (ret)
> +				goto out;
> +			read++;
> +			cnt--;
> +		}
> +
> +		/* only spaces were written */
> +		if (isspace(ch)) {
> +			*ppos += read;
> +			ret = read;
> +			goto out;
> +		}
> +
> +		parser->idx = 0;
> +	}
> +
> +	/* read the non-space input */
> +	while (cnt && !isspace(ch)) {
> +		if (parser->idx < parser->size)
> +			parser->buffer[parser->idx++] = ch;
> +		else {
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +		ret = get_user(ch, ubuf++);
> +		if (ret)
> +			goto out;
> +		read++;
> +		cnt--;
> +	}
> +
> +	/* We either got finished input or we have to wait for another call. */
> +	if (isspace(ch)) {
> +		parser->buffer[parser->idx] = 0;
> +		parser->cont = false;
> +	} else {
> +		parser->cont = true;
> +		parser->buffer[parser->idx++] = ch;
> +	}
> +
> +	*ppos += read;
> +	ret = read;
> +
> +out:
> +	return ret;
> +}
> +
>  ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
>  {
>  	int len;
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index b69697b..28247ce 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -616,6 +616,41 @@ static inline int ftrace_trace_task(struct task_struct *task)
>  #endif
>  
>  /*
> + * struct trace_parser - servers for reading the user input separated by spaces
> + * @cont: set if the input is not complete - no final space char was found
> + * @buffer: holds the parsed user input
> + * @idx: user input lenght
> + * @size: buffer size
> + */
> +struct trace_parser {
> +	bool		cont;
> +	char		*buffer;
> +	unsigned	idx;
> +	unsigned	size;
> +};
> +
> +static inline bool trace_parser_loaded(struct trace_parser *parser)
> +{
> +	return (parser->idx != 0);
> +}
> +
> +static inline bool trace_parser_cont(struct trace_parser *parser)
> +{
> +	return parser->cont;
> +}
> +
> +static inline void trace_parser_clear(struct trace_parser *parser)
> +{
> +	parser->cont = false;
> +	parser->idx = 0;
> +}
> +
> +extern int trace_parser_get_init(struct trace_parser *parser, int size);
> +extern void trace_parser_put(struct trace_parser *parser);
> +extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
> +	size_t cnt, loff_t *ppos);
> +
> +/*
>   * trace_iterator_flags is an enumeration that defines bit
>   * positions into trace_flags that controls the output.
>   *
> -- 
> 1.6.3.3
> 

Re: [PATCH 0/6] [GIT PULL] tracing: more updates

[Ingo Molnar]

* Steven Rostedt <rostedt@goodmis.org> wrote:

> 
> Ingo,
> 
> Please pull the latest tip/tracing/core3 tree, which can be found at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
> tip/tracing/core3
> 
> 
> Steven Rostedt (3):
>       tracing: move tgid out of generic entry and into userstack
>       tracing: add lock depth to entries
>       tracing: consolidate code between trace_output.c and trace_function_graph.c
> 
> jolsa@redhat.com (3):
>       tracing: create generic trace parser
>       tracing: trace parser support for set_event
>       tracing: trace parser support for function and graph
> 
> ----
>  include/linux/ftrace_event.h         |    2 +-
>  kernel/trace/ftrace.c                |  150 +++++++++-------------------------
>  kernel/trace/trace.c                 |  117 +++++++++++++++++++++++++-
>  kernel/trace/trace.h                 |   36 ++++++++
>  kernel/trace/trace_events.c          |   64 ++++-----------
>  kernel/trace/trace_functions_graph.c |   26 ++-----
>  kernel/trace/trace_output.c          |   42 ++++++++--
>  kernel/trace/trace_output.h          |    2 +
>  8 files changed, 246 insertions(+), 193 deletions(-)

Pulled, thanks Steve!

	Ingo