From: Tom Zanussi <tom.zanu...@linux.intel.com>
Hi,
This is v5 of the frace error_log patchset. This version updates the
patches according to suggestions from Masami and Namhyung and moves
some of the selftest code from the kprobe/uprobe testcases to a common
function that can be reused by multiple testcases, including the new
error_log testcase.
Changes from v4:
- Merged in the >& -> 2> redirection patch into '[PATCH v5 06/11]
selftests/ftrace: Add error_log testcase for probe errors'
- Added new patch, '[PATCH v5 07/11] selftests/ftrace: Move
kprobe/uprobe check_error() to test.d/functions' that adds a new
ftrace_errlog_check() to test.d/functions, which is based on
check_error() from '[PATCH v5 06/11] selftests/ftrace: Add
error_log testcase for probe errors'
- Modified the kprobe/uprobe test cases to use the common
ftrace_errlog_check()
- Modified the error_log test cases to display the error position
using the common ftrace_errlog_check()
- Updated subject for '[PATCH v5 08/11] selftests/ftrace: Remove
trigger-extended-error-support testcase
- Streamlined the error_log open and write file operations as
suggested by Masami
- Fixed the long lines in '[PATCH v4 04/11] tracing: Use tracing
error_log with trace event filters' as suggested by Namhyung
Changes from v3:
- Added Masami's [PATCH 05/11] tracing: Use tracing error_log with probe
events
- Added Masami's [PATCH 06/11] selftests/ftrace: Add error_log testcase for
probe
- Added [PATCH 11/11] to fix [PATCH 06/11]
- Removed [RFC PATCH v3 4/5] tracing: Use tracing error_log with kprobe events
- Added [PATCH 08/11] selftests/ftrace: Add tracing/error_log testcase
- Removed trigger-extended-error-support testcase
- Changed [n] numbering to [timestamp] numbering as suggested by Masami
- Updated Documentation and README
Changes from v2:
- Added [n] numbering as suggested by Masami
Text from original post:
Last April, I posted an RFC patchset [1] implementing a common
error_log interface as suggested by Masami [2]. We were supposed to
discuss it at Plumbers but that never happened, and Steve recently
asked about patches for a follow-on discussion [3], so here they are.
I incorporated comments from the previous discussion, the most
important of which are:
- Incorporated Steve's suggestion of using static strings as in the
existing trace event filter code, along with err_info indexing into
the string arrays and a position for the error caret.
- Converted all the hist trigger errors and the existing trace event
filter parse errors to use the new interface.
- Converted a few kprobe_event errors to the new interface as
examples, but these will require more work - I didn't spend much
time figuring out how to get the full kprobe command into the error
info, for instance.
- Got rid of the custom single-page ring buffer and used standard
lists instead.
For now, this is implemented on top of the latest 'hist trigger
snapshot and onchange additions' patchset [4].
Below is an example session of a few failed commands and the
corresponding error_log contents:
# echo > /sys/kernel/debug/tracing/error_log
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >>
/sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >>
/sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/error_log
[ 217.431858] hist:sched:sched_wakeup: error: Variable already defined
Command: keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"
^
# echo 'hist:key=comm:p=prio:onchange($q).snapshot()' >
/sys/kernel/debug/tracing/events/sched/sched_waking/trigger
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/error_log
[ 217.431858] hist:sched:sched_wakeup: error: Variable already defined
Command: keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"
^
[ 311.554978] hist:sched:sched_waking: error: Couldn't find onmax or
onchange variable
Command: key=comm:p=prio:onchange($q).snapshot()
^
# echo 'hist:keys=pid' >>
/sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# echo 'hist:keys=pid' >>
/sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
-su: echo: write error: File exists
# echo 'comm="cyclictest"' >
/sys/kernel/debug/tracing/events/sched/sched_wakeup/filter
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/error_log
[ 217.431858] hist:sched:sched_wakeup: error: Variable already defined
Command: keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"
^
[ 311.554978] hist:sched:sched_waking: error: Couldn't find onmax or
onchange variable
Command: key=comm:p=prio:onchange($q).snapshot()
^
[ 715.626153] hist:sched:sched_wakeup: error: Hist trigger already exists
Command: keys=pid
^
[ 730.480310] event filter parse error: error: Invalid operator
Command: comm="cyclictest"
^
# echo "((sig >= 10 && sig < 15) || dsig == 17) && comm != bash" >
/sys/kernel/debug/tracing/events/signal/signal_generate/filter
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/error_log
[ 217.431858] hist:sched:sched_wakeup: error: Variable already defined
Command: keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"
^
[ 311.554978] hist:sched:sched_waking: error: Couldn't find onmax or
onchange variable
Command: key=comm:p=prio:onchange($q).snapshot()
^
[ 715.626153] hist:sched:sched_wakeup: error: Hist trigger already exists
Command: keys=pid
^
[ 730.480310] event filter parse error: error: Invalid operator
Command: comm="cyclictest"
^
[ 800.548673] event filter parse error: error: Field not found
Command: ((sig >= 10 && sig < 15) || dsig == 17) && comm != bash
^
Thanks,
Tom
[1]
https://lore.kernel.org/lkml/cover.1523545519.git.tom.zanu...@linux.intel.com/
[2]
https://lore.kernel.org/lkml/20180406105309.b50ea1a21d2cbd9b0e39d...@kernel.org/
[3]
https://lore.kernel.org/lkml/e885d1fd02e76f121d6cc2bb28e58b523e2434a7.ca...@linux.intel.com/
[4]
https://lore.kernel.org/lkml/cover.1549403369.git.tom.zanu...@linux.intel.com/
The following changes since commit 01c4e8042fc949018b70ded769f959bc3d80e8b6:
tracing: initialize variable in create_dyn_event() (2019-03-22 15:19:34 -0400)
are available in the git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/zanussi/linux-trace.git
ftrace/error_log_v5
Masami Hiramatsu (2):
tracing: Use tracing error_log with probe events
selftests/ftrace: Add error_log testcase for probe errors
Tom Zanussi (9):
tracing: Add tracing error log
tracing: Save the last hist command's associated event name
tracing: Use tracing error_log with hist triggers
tracing: Use tracing error_log with trace event filters
selftests/ftrace: Move kprobe/uprobe check_error() to test.d/functions
selftests/ftrace: Remove trigger-extended-error-support testcase
selftests/ftrace: Add tracing/error_log testcase
tracing: Add tracing/error_log Documentation
tracing: Add error_log to README
Documentation/trace/ftrace.rst | 31 +++
Documentation/trace/histogram.rst | 16 +-
kernel/trace/trace.c | 219 ++++++++++++++++
kernel/trace/trace.h | 4 +
kernel/trace/trace_events_filter.c | 11 +-
kernel/trace/trace_events_hist.c | 221 +++++++++--------
kernel/trace/trace_kprobe.c | 77 +++---
kernel/trace/trace_probe.c | 274 +++++++++++++++------
kernel/trace/trace_probe.h | 77 +++++-
kernel/trace/trace_uprobe.c | 44 +++-
.../ftrace/test.d/ftrace/tracing-error-log.tc | 19 ++
tools/testing/selftests/ftrace/test.d/functions | 12 +
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 85 +++++++
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 23 ++
.../inter-event/trigger-extended-error-support.tc | 28 ---
15 files changed, 874 insertions(+), 267 deletions(-)
create mode 100644
tools/testing/selftests/ftrace/test.d/ftrace/tracing-error-log.tc
create mode 100644
tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
create mode 100644
tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
delete mode 100644
tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-extended-error-support.tc
--
2.14.1
