tracing: print out start and stop in latency traces
authorSteven Rostedt <srostedt@redhat.com>
Wed, 2 Sep 2009 16:27:41 +0000 (12:27 -0400)
committerSteven Rostedt <rostedt@goodmis.org>
Fri, 4 Sep 2009 15:48:12 +0000 (11:48 -0400)
During development of the tracer, we would copy information from
the live tracer to the max tracer with one memcpy. Since then we
added a generic ring buffer and we handle the copies differently now.
Unfortunately, we never copied the critical section information, and
we lost the output:

 #  => started at: kmem_cache_alloc
 #  => ended at:   kmem_cache_alloc

This patch adds back the critical start and end copying as well as
removes the unused "trace_idx" and "overrun" fields of the
trace_array_cpu structure.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
kernel/trace/trace.c
kernel/trace/trace.h

index 0f0881676dc98f9cfdb0ac622d01ef9d6a24944d..df2c9f730ac6c19276ac322b8691b68a772f20de 100644 (file)
@@ -407,19 +407,22 @@ static void
 __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 {
        struct trace_array_cpu *data = tr->data[cpu];
+       struct trace_array_cpu *max_data = tr->data[cpu];
 
        max_tr.cpu = cpu;
        max_tr.time_start = data->preempt_timestamp;
 
-       data = max_tr.data[cpu];
-       data->saved_latency = tracing_max_latency;
+       max_data = max_tr.data[cpu];
+       max_data->saved_latency = tracing_max_latency;
+       max_data->critical_start = data->critical_start;
+       max_data->critical_end = data->critical_end;
 
        memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
-       data->pid = tsk->pid;
-       data->uid = task_uid(tsk);
-       data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
-       data->policy = tsk->policy;
-       data->rt_priority = tsk->rt_priority;
+       max_data->pid = tsk->pid;
+       max_data->uid = task_uid(tsk);
+       max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
+       max_data->policy = tsk->policy;
+       max_data->rt_priority = tsk->rt_priority;
 
        /* record this tasks comm */
        tracing_record_cmdline(tsk);
@@ -1501,7 +1504,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
                seq_puts(m, "\n#  => ended at:   ");
                seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
                trace_print_seq(m, &iter->seq);
-               seq_puts(m, "#\n");
+               seq_puts(m, "\n#\n");
        }
 
        seq_puts(m, "#\n");
index e2c06b21dd828f9131403775f9bb584e91d32d67..f2af713a8bcc0fc48261103323a7e3e75e0c83ed 100644 (file)
@@ -234,9 +234,6 @@ struct trace_array_cpu {
        atomic_t                disabled;
        void                    *buffer_page;   /* ring buffer spare */
 
-       /* these fields get copied into max-trace: */
-       unsigned long           trace_idx;
-       unsigned long           overrun;
        unsigned long           saved_latency;
        unsigned long           critical_start;
        unsigned long           critical_end;