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authorDmitry Safonov <0x7f454c46@gmail.com>2015-11-06 22:07:26 +0300
committerSteven Rostedt <rostedt@goodmis.org>2015-11-07 13:25:14 -0500
commit03e88ae6b369da2a26a6e09ad165e57d210789cd (patch)
tree263c536f2003d6cd3779b85cdf4988ab9b88c0ca
parent8b1291994d8e5e621a8af7e165b106e50d04bbf1 (diff)
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tracing: Remove unused ftrace_cpu_disabled per cpu variable
Since the ring buffer is lockless, there is no need to disable ftrace on CPU. And no one doing so: after commit 68179686ac67cb ("tracing: Remove ftrace_disable/enable_cpu()") ftrace_cpu_disabled stays the same after initialization, nothing changes it. ftrace_cpu_disabled shouldn't be used by any external module since it disables only function and graph_function tracers but not any other tracer. Link: http://lkml.kernel.org/r/1446836846-22239-1-git-send-email-0x7f454c46@gmail.com Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
-rw-r--r--kernel/trace/trace.c6
-rw-r--r--kernel/trace/trace.h1
-rw-r--r--kernel/trace/trace_functions_graph.c6
3 files changed, 0 insertions, 13 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 08af79c106e1..b11582618991 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -100,8 +100,6 @@ static DEFINE_PER_CPU(bool, trace_cmdline_save);
*/
static int tracing_disabled = 1;
-DEFINE_PER_CPU(int, ftrace_cpu_disabled);
-
cpumask_var_t __read_mostly tracing_buffer_mask;
/*
@@ -1775,10 +1773,6 @@ trace_function(struct trace_array *tr,
struct ring_buffer_event *event;
struct ftrace_entry *entry;
- /* If we are reading the ring buffer, don't trace */
- if (unlikely(__this_cpu_read(ftrace_cpu_disabled)))
- return;
-
event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
flags, pc);
if (!event)
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index dd7620802e72..919d9d07686f 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -667,7 +667,6 @@ extern int DYN_FTRACE_TEST_NAME2(void);
extern bool ring_buffer_expanded;
extern bool tracing_selftest_disabled;
-DECLARE_PER_CPU(int, ftrace_cpu_disabled);
#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 92382af7a213..a663cbb84107 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -288,9 +288,6 @@ int __trace_graph_entry(struct trace_array *tr,
struct ring_buffer *buffer = tr->trace_buffer.buffer;
struct ftrace_graph_ent_entry *entry;
- if (unlikely(__this_cpu_read(ftrace_cpu_disabled)))
- return 0;
-
event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT,
sizeof(*entry), flags, pc);
if (!event)
@@ -403,9 +400,6 @@ void __trace_graph_return(struct trace_array *tr,
struct ring_buffer *buffer = tr->trace_buffer.buffer;
struct ftrace_graph_ret_entry *entry;
- if (unlikely(__this_cpu_read(ftrace_cpu_disabled)))
- return;
-
event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
sizeof(*entry), flags, pc);
if (!event)