Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f8b755ac authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Ingo Molnar
Browse files

tracing/function-graph-tracer: Output arrows signal on hardirq call/return



Impact: make more obvious the hardirq calls in the output

When a hardirq is triggered inside the codeflow on output, we have
now two arrows that indicate the entry and return of the hardirq.

 0)               |          bit_waitqueue() {
 0)   0.880 us    |            __phys_addr();
 0)   2.699 us    |          }
 0)               |          __wake_up_bit() {
 0)   ==========> |          smp_apic_timer_interrupt() {
 0)   0.797 us    |            native_apic_mem_write();
 0)   0.715 us    |            exit_idle();
 0)               |            irq_enter() {
 0)   0.722 us    |              idle_cpu();
 0)   5.519 us    |            }
 0)               |            hrtimer_interrupt() {
 0)               |              ktime_get() {
 0)               |                ktime_get_ts() {
 0)   0.805 us    |                  getnstimeofday();

 [...]

 0) ! 108.528 us  |            }
 0)               |            irq_exit() {
 0)               |              do_softirq() {
 0)               |                __do_softirq() {
 0)   0.895 us    |                  __local_bh_disable();
 0)               |                  run_timer_softirq() {
 0)   0.827 us    |                    hrtimer_run_pending();
 0)   1.226 us    |                    _spin_lock_irq();
 0)               |                    _spin_unlock_irq() {
 0)   6.550 us    |                  }
 0)   0.924 us    |                  _local_bh_enable();
 0) + 12.129 us   |                }
 0) + 13.911 us   |              }
 0)   0.707 us    |              idle_cpu();
 0) + 17.009 us   |            }
 0) ! 137.419 us  |          }
 0)   <========== |
 0)   1.045 us    |          }
 0) ! 148.908 us  |        }
 0) ! 151.022 us  |      }
 0) ! 153.022 us  |    }
 0)   0.963 us    |    journal_mark_dirty();
 0)   0.925 us    |    __brelse();

Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent bcbc4f20
Loading
Loading
Loading
Loading
+62 −4
Original line number Diff line number Diff line
@@ -231,6 +231,49 @@ trace_branch_is_leaf(struct trace_iterator *iter,
	return true;
}

static enum print_line_t
print_graph_irq(struct trace_seq *s, unsigned long addr,
				enum trace_type type, int cpu, pid_t pid)
{
	int ret;

	if (addr < (unsigned long)__irqentry_text_start ||
		addr >= (unsigned long)__irqentry_text_end)
		return TRACE_TYPE_UNHANDLED;

	if (type == TRACE_GRAPH_ENT) {
		ret = trace_seq_printf(s, "==========> |  ");
	} else {
		/* Cpu */
		if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
			ret = print_graph_cpu(s, cpu);
			if (ret == TRACE_TYPE_PARTIAL_LINE)
				return TRACE_TYPE_PARTIAL_LINE;
		}
		/* Proc */
		if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
			ret = print_graph_proc(s, pid);
			if (ret == TRACE_TYPE_PARTIAL_LINE)
				return TRACE_TYPE_PARTIAL_LINE;

			ret = trace_seq_printf(s, " | ");
			if (!ret)
				return TRACE_TYPE_PARTIAL_LINE;
		}

		/* No overhead */
		if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
			ret = trace_seq_printf(s, "  ");
			if (!ret)
				return TRACE_TYPE_PARTIAL_LINE;
		}

		ret = trace_seq_printf(s, "<========== |\n");
	}
	if (!ret)
		return TRACE_TYPE_PARTIAL_LINE;
	return TRACE_TYPE_HANDLED;
}

static enum print_line_t
print_graph_duration(unsigned long long duration, struct trace_seq *s)
@@ -344,7 +387,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,

static enum print_line_t
print_graph_entry_nested(struct ftrace_graph_ent_entry *entry,
			struct trace_seq *s)
			struct trace_seq *s, pid_t pid, int cpu)
{
	int i;
	int ret;
@@ -357,8 +400,18 @@ print_graph_entry_nested(struct ftrace_graph_ent_entry *entry,
			return TRACE_TYPE_PARTIAL_LINE;
	}

	/* Interrupt */
	ret = print_graph_irq(s, call->func, TRACE_GRAPH_ENT, cpu, pid);
	if (ret == TRACE_TYPE_UNHANDLED) {
		/* No time */
		ret = trace_seq_printf(s, "            |  ");
		if (!ret)
			return TRACE_TYPE_PARTIAL_LINE;
	} else {
		if (ret == TRACE_TYPE_PARTIAL_LINE)
			return TRACE_TYPE_PARTIAL_LINE;
	}


	/* Function */
	for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
@@ -410,7 +463,7 @@ print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
	if (trace_branch_is_leaf(iter, field))
		return print_graph_entry_leaf(iter, field, s);
	else
		return print_graph_entry_nested(field, s);
		return print_graph_entry_nested(field, s, iter->ent->pid, cpu);

}

@@ -474,6 +527,11 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
		if (!ret)
			return TRACE_TYPE_PARTIAL_LINE;
	}

	ret = print_graph_irq(s, trace->func, TRACE_GRAPH_RET, cpu, ent->pid);
	if (ret == TRACE_TYPE_PARTIAL_LINE)
		return TRACE_TYPE_PARTIAL_LINE;

	return TRACE_TYPE_HANDLED;
}