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authorChangbin Du <changbin.du@gmail.com>2019-01-01 16:46:10 +0100
committerSteven Rostedt (VMware) <rostedt@goodmis.org>2019-02-06 17:56:18 +0100
commit9acd8de69d107537a68d010c9149fa9d9aba91f4 (patch)
tree38d0a608a4b6c4364d176d1be82dff5ee1b186e9 /kernel
parentLinux 5.0-rc5 (diff)
downloadlinux-9acd8de69d107537a68d010c9149fa9d9aba91f4.tar.xz
linux-9acd8de69d107537a68d010c9149fa9d9aba91f4.zip
function_graph: Support displaying relative timestamp
When function_graph is used for latency tracers, relative timestamp is more straightforward than absolute timestamp as function trace does. This change adds relative timestamp support to function_graph and applies to latency tracers (wakeup and irqsoff). Instead of: # tracer: irqsoff # # irqsoff latency trace v1.1.5 on 5.0.0-rc1-test # -------------------------------------------------------------------- # latency: 521 us, #1125/1125, CPU#2 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:8) # ----------------- # | task: swapper/2-0 (uid:0 nice:0 policy:0 rt_prio:0) # ----------------- # => started at: __schedule # => ended at: _raw_spin_unlock_irq # # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / # TIME CPU TASK/PID |||| DURATION FUNCTION CALLS # | | | | |||| | | | | | | 124.974306 | 2) systemd-693 | d..1 0.000 us | __schedule(); 124.974307 | 2) systemd-693 | d..1 | rcu_note_context_switch() { 124.974308 | 2) systemd-693 | d..1 0.487 us | rcu_preempt_deferred_qs(); 124.974309 | 2) systemd-693 | d..1 0.451 us | rcu_qs(); 124.974310 | 2) systemd-693 | d..1 2.301 us | } [..] 124.974826 | 2) <idle>-0 | d..2 | finish_task_switch() { 124.974826 | 2) <idle>-0 | d..2 | _raw_spin_unlock_irq() { 124.974827 | 2) <idle>-0 | d..2 0.000 us | _raw_spin_unlock_irq(); 124.974828 | 2) <idle>-0 | d..2 0.000 us | tracer_hardirqs_on(); <idle>-0 2d..2 552us : <stack trace> => __schedule => schedule_idle => do_idle => cpu_startup_entry => start_secondary => secondary_startup_64 Show: # tracer: irqsoff # # irqsoff latency trace v1.1.5 on 5.0.0-rc1-test+ # -------------------------------------------------------------------- # latency: 511 us, #1053/1053, CPU#7 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:8) # ----------------- # | task: swapper/7-0 (uid:0 nice:0 policy:0 rt_prio:0) # ----------------- # => started at: __schedule # => ended at: _raw_spin_unlock_irq # # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / # REL TIME CPU TASK/PID |||| DURATION FUNCTION CALLS # | | | | |||| | | | | | | 0 us | 7) sshd-1704 | d..1 0.000 us | __schedule(); 1 us | 7) sshd-1704 | d..1 | rcu_note_context_switch() { 1 us | 7) sshd-1704 | d..1 0.611 us | rcu_preempt_deferred_qs(); 2 us | 7) sshd-1704 | d..1 0.484 us | rcu_qs(); 3 us | 7) sshd-1704 | d..1 2.599 us | } [..] 509 us | 7) <idle>-0 | d..2 | finish_task_switch() { 510 us | 7) <idle>-0 | d..2 | _raw_spin_unlock_irq() { 510 us | 7) <idle>-0 | d..2 0.000 us | _raw_spin_unlock_irq(); 512 us | 7) <idle>-0 | d..2 0.000 us | tracer_hardirqs_on(); <idle>-0 7d..2 543us : <stack trace> => __schedule => schedule_idle => do_idle => cpu_startup_entry => start_secondary => secondary_startup_64 Link: http://lkml.kernel.org/r/20190101154614.8887-2-changbin.du@gmail.com Signed-off-by: Changbin Du <changbin.du@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/trace/trace.h9
-rw-r--r--kernel/trace/trace_functions_graph.c25
-rw-r--r--kernel/trace/trace_irqsoff.c2
-rw-r--r--kernel/trace/trace_sched_wakeup.c2
4 files changed, 32 insertions, 6 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 08900828d282..a34fa5e76abb 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -855,10 +855,11 @@ static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
#define TRACE_GRAPH_PRINT_PROC 0x8
#define TRACE_GRAPH_PRINT_DURATION 0x10
#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
-#define TRACE_GRAPH_PRINT_IRQS 0x40
-#define TRACE_GRAPH_PRINT_TAIL 0x80
-#define TRACE_GRAPH_SLEEP_TIME 0x100
-#define TRACE_GRAPH_GRAPH_TIME 0x200
+#define TRACE_GRAPH_PRINT_REL_TIME 0x40
+#define TRACE_GRAPH_PRINT_IRQS 0x80
+#define TRACE_GRAPH_PRINT_TAIL 0x100
+#define TRACE_GRAPH_SLEEP_TIME 0x200
+#define TRACE_GRAPH_GRAPH_TIME 0x400
#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index c2af1560e856..16ebbdd7b22e 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -501,6 +501,17 @@ static void print_graph_abs_time(u64 t, struct trace_seq *s)
}
static void
+print_graph_rel_time(struct trace_iterator *iter, struct trace_seq *s)
+{
+ unsigned long long usecs;
+
+ usecs = iter->ts - iter->trace_buffer->time_start;
+ do_div(usecs, NSEC_PER_USEC);
+
+ trace_seq_printf(s, "%9llu us | ", usecs);
+}
+
+static void
print_graph_irq(struct trace_iterator *iter, unsigned long addr,
enum trace_type type, int cpu, pid_t pid, u32 flags)
{
@@ -517,6 +528,10 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
print_graph_abs_time(iter->ts, s);
+ /* Relative time */
+ if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+ print_graph_rel_time(iter, s);
+
/* Cpu */
if (flags & TRACE_GRAPH_PRINT_CPU)
print_graph_cpu(s, cpu);
@@ -725,6 +740,10 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
print_graph_abs_time(iter->ts, s);
+ /* Relative time */
+ if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+ print_graph_rel_time(iter, s);
+
/* Cpu */
if (flags & TRACE_GRAPH_PRINT_CPU)
print_graph_cpu(s, cpu);
@@ -1101,6 +1120,8 @@ static void print_lat_header(struct seq_file *s, u32 flags)
if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
size += 16;
+ if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+ size += 16;
if (flags & TRACE_GRAPH_PRINT_CPU)
size += 4;
if (flags & TRACE_GRAPH_PRINT_PROC)
@@ -1125,6 +1146,8 @@ static void __print_graph_headers_flags(struct trace_array *tr,
seq_putc(s, '#');
if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
seq_puts(s, " TIME ");
+ if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+ seq_puts(s, " REL TIME ");
if (flags & TRACE_GRAPH_PRINT_CPU)
seq_puts(s, " CPU");
if (flags & TRACE_GRAPH_PRINT_PROC)
@@ -1139,6 +1162,8 @@ static void __print_graph_headers_flags(struct trace_array *tr,
seq_putc(s, '#');
if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
seq_puts(s, " | ");
+ if (flags & TRACE_GRAPH_PRINT_REL_TIME)
+ seq_puts(s, " | ");
if (flags & TRACE_GRAPH_PRINT_CPU)
seq_puts(s, " | ");
if (flags & TRACE_GRAPH_PRINT_PROC)
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index d3294721f119..e6a62e7c6b69 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -238,7 +238,7 @@ static void irqsoff_trace_close(struct trace_iterator *iter)
#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \
TRACE_GRAPH_PRINT_PROC | \
- TRACE_GRAPH_PRINT_ABS_TIME | \
+ TRACE_GRAPH_PRINT_REL_TIME | \
TRACE_GRAPH_PRINT_DURATION)
static enum print_line_t irqsoff_print_line(struct trace_iterator *iter)
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 4ea7e6845efb..b6c5fa10347e 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -180,7 +180,7 @@ static void wakeup_trace_close(struct trace_iterator *iter)
}
#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \
- TRACE_GRAPH_PRINT_ABS_TIME | \
+ TRACE_GRAPH_PRINT_REL_TIME | \
TRACE_GRAPH_PRINT_DURATION)
static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 20:54:45 +0100