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authorJungseok Lee <jungseoklee85@gmail.com>2015-07-11 14:51:40 +0000
committerSteven Rostedt <rostedt@goodmis.org>2015-07-20 22:30:52 -0400
commitb838e1d96c613019095ba008afbee800977b0582 (patch)
tree15f8f4c15836f7617a91c167fe46be3cef63bb10 /Documentation/trace
parent82c355e81afbf16bc1ab379899a79eb66e2b7504 (diff)
downloadlwn-b838e1d96c613019095ba008afbee800977b0582.tar.gz
lwn-b838e1d96c613019095ba008afbee800977b0582.zip
tracing: Introduce two additional marks for delay
A fine granulity support for delay would be very useful when profiling VM logics, such as page allocation including page reclaim and memory compaction with function graph. Thus, this patch adds two additional marks with two changes. - An equal sign in mark selection function is removed to align code behavior with comments and documentation. - The function graph example related to delay in ftrace.txt is updated to cover all supported marks. Link: http://lkml.kernel.org/r/1436626300-1679-3-git-send-email-jungseoklee85@gmail.com Cc: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'Documentation/trace')
-rw-r--r--Documentation/trace/ftrace.txt51
1 files changed, 38 insertions, 13 deletions
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index 7ddb1e319f84..072d3c4d5753 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -686,6 +686,8 @@ The above is mostly meaningful for kernel developers.
The marks are determined by the difference between this
current trace and the next trace.
'$' - greater than 1 second
+ '@' - greater than 100 milisecond
+ '*' - greater than 10 milisecond
'#' - greater than 1000 microsecond
'!' - greater than 100 microsecond
'+' - greater than 10 microsecond
@@ -1939,26 +1941,49 @@ want, depending on your needs.
ie:
- 0) | up_write() {
- 0) 0.646 us | _spin_lock_irqsave();
- 0) 0.684 us | _spin_unlock_irqrestore();
- 0) 3.123 us | }
- 0) 0.548 us | fput();
- 0) + 58.628 us | }
+ 3) # 1837.709 us | } /* __switch_to */
+ 3) | finish_task_switch() {
+ 3) 0.313 us | _raw_spin_unlock_irq();
+ 3) 3.177 us | }
+ 3) # 1889.063 us | } /* __schedule */
+ 3) ! 140.417 us | } /* __schedule */
+ 3) # 2034.948 us | } /* schedule */
+ 3) * 33998.59 us | } /* schedule_preempt_disabled */
[...]
- 0) | putname() {
- 0) | kmem_cache_free() {
- 0) 0.518 us | __phys_addr();
- 0) 1.757 us | }
- 0) 2.861 us | }
- 0) ! 115.305 us | }
- 0) ! 116.402 us | }
+ 1) 0.260 us | msecs_to_jiffies();
+ 1) 0.313 us | __rcu_read_unlock();
+ 1) + 61.770 us | }
+ 1) + 64.479 us | }
+ 1) 0.313 us | rcu_bh_qs();
+ 1) 0.313 us | __local_bh_enable();
+ 1) ! 217.240 us | }
+ 1) 0.365 us | idle_cpu();
+ 1) | rcu_irq_exit() {
+ 1) 0.417 us | rcu_eqs_enter_common.isra.47();
+ 1) 3.125 us | }
+ 1) ! 227.812 us | }
+ 1) ! 457.395 us | }
+ 1) @ 119760.2 us | }
+
+ [...]
+
+ 2) | handle_IPI() {
+ 1) 6.979 us | }
+ 2) 0.417 us | scheduler_ipi();
+ 1) 9.791 us | }
+ 1) + 12.917 us | }
+ 2) 3.490 us | }
+ 1) + 15.729 us | }
+ 1) + 18.542 us | }
+ 2) $ 3594274 us | }
+ means that the function exceeded 10 usecs.
! means that the function exceeded 100 usecs.
# means that the function exceeded 1000 usecs.
+ * means that the function exceeded 10 msecs.
+ @ means that the function exceeded 100 msecs.
$ means that the function exceeded 1 sec.