Merge branch 'tip/perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/core

7 files changed, 76 insertions, 14 deletions

diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 28d0615a513f..3632ce87674f 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -443,6 +443,7 @@ int ring_buffer_print_page_header(struct trace_seq *s)
  */
 struct ring_buffer_per_cpu {
         int                             cpu;
+        atomic_t                        record_disabled;
         struct ring_buffer              *buffer;
         spinlock_t                      reader_lock;    /* serialize readers */
         arch_spinlock_t                 lock;
@@ -462,7 +463,6 @@ struct ring_buffer_per_cpu {
         unsigned long                   read;
         u64                             write_stamp;
         u64                             read_stamp;
-        atomic_t                        record_disabled;
 };
 
 struct ring_buffer {
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c1752dac613e..4b1122d0df37 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -344,7 +344,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
 /* trace_flags holds trace_options default values */
 unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
         TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
-        TRACE_ITER_GRAPH_TIME;
+        TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD;
 
 static int trace_stop_count;
 static DEFINE_SPINLOCK(tracing_start_lock);
@@ -428,6 +428,7 @@ static const char *trace_options[] = {
         "latency-format",
         "sleep-time",
         "graph-time",
+        "record-cmd",
         NULL
 };
 
@@ -659,6 +660,10 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
                 return;
 
         WARN_ON_ONCE(!irqs_disabled());
+        if (!current_trace->use_max_tr) {
+                WARN_ON_ONCE(1);
+                return;
+        }
         arch_spin_lock(&ftrace_max_lock);
 
         tr->buffer = max_tr.buffer;
@@ -685,6 +690,11 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
                 return;
 
         WARN_ON_ONCE(!irqs_disabled());
+        if (!current_trace->use_max_tr) {
+                WARN_ON_ONCE(1);
+                return;
+        }
+
         arch_spin_lock(&ftrace_max_lock);
 
         ftrace_disable_cpu();
@@ -729,7 +739,7 @@ __acquires(kernel_lock)
                 return -1;
         }
 
-        if (strlen(type->name) > MAX_TRACER_SIZE) {
+        if (strlen(type->name) >= MAX_TRACER_SIZE) {
                 pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
                 return -1;
         }
@@ -2508,6 +2518,9 @@ static void set_tracer_flags(unsigned int mask, int enabled)
                 trace_flags |= mask;
         else
                 trace_flags &= ~mask;
+
+        if (mask == TRACE_ITER_RECORD_CMD)
+                trace_event_enable_cmd_record(enabled);
 }
 
 static ssize_t
@@ -2746,6 +2759,9 @@ static int tracing_resize_ring_buffer(unsigned long size)
         if (ret < 0)
                 return ret;
 
+        if (!current_trace->use_max_tr)
+                goto out;
+
         ret = ring_buffer_resize(max_tr.buffer, size);
         if (ret < 0) {
                 int r;
@@ -2773,11 +2789,14 @@ static int tracing_resize_ring_buffer(unsigned long size)
                 return ret;
         }
 
+        max_tr.entries = size;
+ out:
         global_trace.entries = size;
 
         return ret;
 }
 
+
 /**
  * tracing_update_buffers - used by tracing facility to expand ring buffers
  *
@@ -2838,12 +2857,26 @@ static int tracing_set_tracer(const char *buf)
         trace_branch_disable();
         if (current_trace && current_trace->reset)
                 current_trace->reset(tr);
-
+        if (current_trace && current_trace->use_max_tr) {
+                /*
+                 * We don't free the ring buffer. instead, resize it because
+                 * The max_tr ring buffer has some state (e.g. ring->clock) and
+                 * we want preserve it.
+                 */
+                ring_buffer_resize(max_tr.buffer, 1);
+                max_tr.entries = 1;
+        }
         destroy_trace_option_files(topts);
 
         current_trace = t;
 
         topts = create_trace_option_files(current_trace);
+        if (current_trace->use_max_tr) {
+                ret = ring_buffer_resize(max_tr.buffer, global_trace.entries);
+                if (ret < 0)
+                        goto out;
+                max_tr.entries = global_trace.entries;
+        }
 
         if (t->init) {
                 ret = tracer_init(t, tr);
@@ -3426,7 +3459,6 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
         }
 
         tracing_start();
-        max_tr.entries = global_trace.entries;
         mutex_unlock(&trace_types_lock);
 
         return cnt;
@@ -4531,16 +4563,14 @@ __init static int tracer_alloc_buffers(void)
 
 
 #ifdef CONFIG_TRACER_MAX_TRACE
-        max_tr.buffer = ring_buffer_alloc(ring_buf_size,
-                                             TRACE_BUFFER_FLAGS);
+        max_tr.buffer = ring_buffer_alloc(1, TRACE_BUFFER_FLAGS);
         if (!max_tr.buffer) {
                 printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
                 WARN_ON(1);
                 ring_buffer_free(global_trace.buffer);
                 goto out_free_cpumask;
         }
-        max_tr.entries = ring_buffer_size(max_tr.buffer);
-        WARN_ON(max_tr.entries != global_trace.entries);
+        max_tr.entries = 1;
 #endif
 
         /* Allocate the first page for all buffers */
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 638a5887e2ec..d05c873dd4b2 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -274,6 +274,7 @@ struct tracer {
         struct tracer           *next;
         int                     print_max;
         struct tracer_flags     *flags;
+        int                     use_max_tr;
 };
 
 
@@ -581,6 +582,7 @@ enum trace_iterator_flags {
         TRACE_ITER_LATENCY_FMT          = 0x20000,
         TRACE_ITER_SLEEP_TIME           = 0x40000,
         TRACE_ITER_GRAPH_TIME           = 0x80000,
+        TRACE_ITER_RECORD_CMD           = 0x100000,
 };
 
 /*
@@ -713,6 +715,8 @@ filter_check_discard(struct ftrace_event_call *call, void *rec,
         return 0;
 }
 
+extern void trace_event_enable_cmd_record(bool enable);
+
 extern struct mutex event_mutex;
 extern struct list_head ftrace_events;
 
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index e8e6043f4d29..09b4fa6e4d3b 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -170,6 +170,26 @@ int ftrace_event_reg(struct ftrace_event_call *call, enum trace_reg type)
 }
 EXPORT_SYMBOL_GPL(ftrace_event_reg);
 
+void trace_event_enable_cmd_record(bool enable)
+{
+        struct ftrace_event_call *call;
+
+        mutex_lock(&event_mutex);
+        list_for_each_entry(call, &ftrace_events, list) {
+                if (!(call->flags & TRACE_EVENT_FL_ENABLED))
+                        continue;
+
+                if (enable) {
+                        tracing_start_cmdline_record();
+                        call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
+                } else {
+                        tracing_stop_cmdline_record();
+                        call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
+                }
+        }
+        mutex_unlock(&event_mutex);
+}
+
 static int ftrace_event_enable_disable(struct ftrace_event_call *call,
                                         int enable)
 {
@@ -179,13 +199,19 @@ static int ftrace_event_enable_disable(struct ftrace_event_call *call,
         case 0:
                 if (call->flags & TRACE_EVENT_FL_ENABLED) {
                         call->flags &= ~TRACE_EVENT_FL_ENABLED;
-                        tracing_stop_cmdline_record();
+                        if (call->flags & TRACE_EVENT_FL_RECORDED_CMD) {
+                                tracing_stop_cmdline_record();
+                                call->flags &= ~TRACE_EVENT_FL_RECORDED_CMD;
+                        }
                         call->class->reg(call, TRACE_REG_UNREGISTER);
                 }
                 break;
         case 1:
                 if (!(call->flags & TRACE_EVENT_FL_ENABLED)) {
-                        tracing_start_cmdline_record();
+                        if (trace_flags & TRACE_ITER_RECORD_CMD) {
+                                tracing_start_cmdline_record();
+                                call->flags |= TRACE_EVENT_FL_RECORDED_CMD;
+                        }
                         ret = call->class->reg(call, TRACE_REG_REGISTER);
                         if (ret) {
                                 tracing_stop_cmdline_record();
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 6fd486e0cef4..73a6b0601f2e 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -649,6 +649,7 @@ static struct tracer irqsoff_tracer __read_mostly =
 #endif
         .open           = irqsoff_trace_open,
         .close          = irqsoff_trace_close,
+        .use_max_tr     = 1,
 };
 # define register_irqsoff(trace) register_tracer(&trace)
 #else
@@ -681,6 +682,7 @@ static struct tracer preemptoff_tracer __read_mostly =
 #endif
         .open           = irqsoff_trace_open,
         .close          = irqsoff_trace_close,
+        .use_max_tr     = 1,
 };
 # define register_preemptoff(trace) register_tracer(&trace)
 #else
@@ -715,6 +717,7 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
 #endif
         .open           = irqsoff_trace_open,
         .close          = irqsoff_trace_close,
+        .use_max_tr     = 1,
 };
 
 # define register_preemptirqsoff(trace) register_tracer(&trace)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index a46197b80b7f..02272baa2206 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -16,9 +16,6 @@
 
 DECLARE_RWSEM(trace_event_mutex);
 
-DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq);
-EXPORT_PER_CPU_SYMBOL(ftrace_event_seq);
-
 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
 
 static int next_event_type = __TRACE_LAST_TYPE + 1;
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index c9fd5bd02036..4086eae6e81b 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -382,6 +382,7 @@ static struct tracer wakeup_tracer __read_mostly =
 #ifdef CONFIG_FTRACE_SELFTEST
         .selftest    = trace_selftest_startup_wakeup,
 #endif
+        .use_max_tr     = 1,
 };
 
 static struct tracer wakeup_rt_tracer __read_mostly =
@@ -396,6 +397,7 @@ static struct tracer wakeup_rt_tracer __read_mostly =
 #ifdef CONFIG_FTRACE_SELFTEST
         .selftest    = trace_selftest_startup_wakeup,
 #endif
+        .use_max_tr     = 1,
 };
 
 __init static int init_wakeup_tracer(void)