ftrace: sched_switch: show the wakee's cpu

While profiling the smp behaviour of the scheduler it was needed to know to
which cpu a task got woken.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 10 insertions, 3 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8a00d6c5c0f5..7e6cb4fe62f2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -977,6 +977,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
         entry->field.ctx.next_pid       = next->pid;
         entry->field.ctx.next_prio      = next->prio;
         entry->field.ctx.next_state     = next->state;
+        entry->field.ctx.next_cpu       = task_cpu(next);
         __trace_stack(tr, data, flags, 5);
         __raw_spin_unlock(&data->lock);
         raw_local_irq_restore(irq_flags);
@@ -1003,6 +1004,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
         entry->field.ctx.next_pid       = wakee->pid;
         entry->field.ctx.next_prio      = wakee->prio;
         entry->field.ctx.next_state     = wakee->state;
+        entry->field.ctx.next_cpu       = task_cpu(wakee);
         __trace_stack(tr, data, flags, 6);
         __raw_spin_unlock(&data->lock);
         raw_local_irq_restore(irq_flags);
@@ -1636,10 +1638,11 @@ print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
                         __ffs(field->ctx.prev_state) + 1 : 0;
                 S = state < sizeof(state_to_char) - 1 ? state_to_char[state] : 'X';
                 comm = trace_find_cmdline(field->ctx.next_pid);
-                trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c %s\n",
+                trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
                                  field->ctx.prev_pid,
                                  field->ctx.prev_prio,
                                  S, entry->type == TRACE_CTX ? "==>" : "  +",
+                                 field->ctx.next_cpu,
                                  field->ctx.next_pid,
                                  field->ctx.next_prio,
                                  T, comm);
@@ -1736,11 +1739,12 @@ static int print_trace_fmt(struct trace_iterator *iter)
                         state_to_char[field->ctx.prev_state] : 'X';
                 T = field->ctx.next_state < sizeof(state_to_char) ?
                         state_to_char[field->ctx.next_state] : 'X';
-                ret = trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c\n",
+                ret = trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c\n",
                                        field->ctx.prev_pid,
                                        field->ctx.prev_prio,
                                        S,
                                        entry->type == TRACE_CTX ? "==>" : "  +",
+                                       field->ctx.next_cpu,
                                        field->ctx.next_pid,
                                        field->ctx.next_prio,
                                        T);
@@ -1817,10 +1821,11 @@ static int print_raw_fmt(struct trace_iterator *iter)
                         state_to_char[field->ctx.next_state] : 'X';
                 if (entry->type == TRACE_WAKE)
                         S = '+';
-                ret = trace_seq_printf(s, "%d %d %c %d %d %c\n",
+                ret = trace_seq_printf(s, "%d %d %c %d %d %d %c\n",
                                        field->ctx.prev_pid,
                                        field->ctx.prev_prio,
                                        S,
+                                       field->ctx.next_cpu,
                                        field->ctx.next_pid,
                                        field->ctx.next_prio,
                                        T);
@@ -1893,6 +1898,7 @@ static int print_hex_fmt(struct trace_iterator *iter)
                 SEQ_PUT_HEX_FIELD_RET(s, field->ctx.prev_pid);
                 SEQ_PUT_HEX_FIELD_RET(s, field->ctx.prev_prio);
                 SEQ_PUT_HEX_FIELD_RET(s, S);
+                SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_cpu);
                 SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_pid);
                 SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_prio);
                 SEQ_PUT_HEX_FIELD_RET(s, T);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 5f54c875c8be..77c265f6a779 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -41,6 +41,7 @@ struct ctx_switch_entry {
         unsigned int            next_pid;
         unsigned char           next_prio;
         unsigned char           next_state;
+        unsigned int            next_cpu;
 };
 
 /*