From: Steven Rostedt <rostedt@goodmis.org>
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Masami Hiramatsu <mhiramat@kernel.org>,
Tom Zanussi <zanussi@kernel.org>
Subject: [for-next][PATCH 07/21] tracing: Add trace_array_find/_get() to find instance trace arrays
Date: Thu, 30 Jan 2020 09:47:50 -0500 [thread overview]
Message-ID: <20200130144811.265074620@goodmis.org> (raw)
In-Reply-To: 20200130144743.527378179@goodmis.org
From: Tom Zanussi <zanussi@kernel.org>
Add a new trace_array_find() function that can be used to find a trace
array given the instance name, and replace existing code that does the
same thing with it. Also add trace_array_find_get() which does the
same but returns the trace array after upping its refcount.
Also make both available for use outside of trace.c.
Link: http://lkml.kernel.org/r/cb68528c975eba95bee4561ac67dd1499423b2e5.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
kernel/trace/trace.c | 43 +++++++++++++++++++++++++++++++++----------
kernel/trace/trace.h | 2 ++
2 files changed, 35 insertions(+), 10 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8d144fd94aa8..183b031a3828 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -8499,6 +8499,34 @@ static void update_tracer_options(struct trace_array *tr)
mutex_unlock(&trace_types_lock);
}
+/* Must have trace_types_lock held */
+struct trace_array *trace_array_find(const char *instance)
+{
+ struct trace_array *tr, *found = NULL;
+
+ list_for_each_entry(tr, &ftrace_trace_arrays, list) {
+ if (tr->name && strcmp(tr->name, instance) == 0) {
+ found = tr;
+ break;
+ }
+ }
+
+ return found;
+}
+
+struct trace_array *trace_array_find_get(const char *instance)
+{
+ struct trace_array *tr;
+
+ mutex_lock(&trace_types_lock);
+ tr = trace_array_find(instance);
+ if (tr)
+ tr->ref++;
+ mutex_unlock(&trace_types_lock);
+
+ return tr;
+}
+
static struct trace_array *trace_array_create(const char *name)
{
struct trace_array *tr;
@@ -8575,10 +8603,8 @@ static int instance_mkdir(const char *name)
mutex_lock(&trace_types_lock);
ret = -EEXIST;
- list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (tr->name && strcmp(tr->name, name) == 0)
- goto out_unlock;
- }
+ if (trace_array_find(name))
+ goto out_unlock;
tr = trace_array_create(name);
@@ -8706,12 +8732,9 @@ static int instance_rmdir(const char *name)
mutex_lock(&trace_types_lock);
ret = -ENODEV;
- list_for_each_entry(tr, &ftrace_trace_arrays, list) {
- if (tr->name && strcmp(tr->name, name) == 0) {
- ret = __remove_instance(tr);
- break;
- }
- }
+ tr = trace_array_find(name);
+ if (tr)
+ ret = __remove_instance(tr);
mutex_unlock(&trace_types_lock);
mutex_unlock(&event_mutex);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index b3075b637d14..f5480a2aa334 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -358,6 +358,8 @@ extern struct mutex trace_types_lock;
extern int trace_array_get(struct trace_array *tr);
extern int tracing_check_open_get_tr(struct trace_array *tr);
+extern struct trace_array *trace_array_find(const char *instance);
+extern struct trace_array *trace_array_find_get(const char *instance);
extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
--
2.24.1
next prev parent reply other threads:[~2020-01-30 14:48 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-30 14:47 [for-next][PATCH 00/21] tracing: Some more last minute updates for 5.6 Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 01/21] tracing/boot: Include required headers and sort it alphabetically Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 02/21] tracing/boot: Move external function declarations to kernel/trace/trace.h Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 03/21] tracing: Fix sched switch start/stop refcount racy updates Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 04/21] ftrace: fpid_next() should increase position index Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 05/21] tracing: eval_map_next() should always " Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 06/21] trigger_next should " Steven Rostedt
2020-01-30 14:47 ` Steven Rostedt [this message]
2020-01-30 14:47 ` [for-next][PATCH 08/21] tracing: Add trace_get/put_event_file() Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 09/21] tracing: Add synth_event_delete() Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 10/21] tracing: Add dynamic event command creation interface Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 11/21] tracing: Add synthetic event command generation functions Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 12/21] tracing: Add synth_event_trace() and related functions Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 13/21] tracing: Add synth event generation test module Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 14/21] tracing: Add kprobe event command generation functions Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 15/21] tracing: Change trace_boot to use kprobe_event interface Steven Rostedt
2020-01-30 14:47 ` [for-next][PATCH 16/21] tracing: Add kprobe event command generation test module Steven Rostedt
2020-01-30 14:48 ` [for-next][PATCH 17/21] tracing: Documentation for in-kernel synthetic event API Steven Rostedt
2020-01-30 14:48 ` [for-next][PATCH 18/21] tracing: Move all function tracing configs together Steven Rostedt
2020-01-30 14:48 ` [for-next][PATCH 19/21] tracing: Move tracing test module " Steven Rostedt
2020-01-30 14:48 ` [for-next][PATCH 20/21] tracing: Move mmio tracer config up with the other tracers Steven Rostedt
2020-01-30 14:48 ` [for-next][PATCH 21/21] tracing: Move tracing selftests to bottom of menu Steven Rostedt
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