Re: [PATCH v3 0/8] tracing/boot: Add new options for tracing specific period
On 9/10/20 7:27 PM, Masami Hiramatsu wrote:
On Thu, 10 Sep 2020 19:34:33 -0400
Steven Rostedt wrote:
On Thu, 10 Sep 2020 17:54:54 +0900
Masami Hiramatsu wrote:
Hi,
Here is the 3rd version of the series to improve the boot-time tracing to
support kretprobe and tracing_on option. Previous version is here:
https://lkml.kernel.org/r/159894698993.1478826.2813843560314595660.stgit@devnote2
This version adds uprobe %return suffix support ([5/8]) and the testcases
([8/8]), and update kprobe %suffix support([4/8]) and the uprobe event
document([6/8]).
The combination of tracing_on and kretprobe allows us to trace events
while a specific function call period. For example, the below bootconfig
will make a function callgraph in the pci_proc_init() function at boot
time.
ftrace {
tracing_on = 0 # off at start
tracer = function_graph
event.kprobes {
start_event {
probes = "pci_proc_init"
actions = "traceon"
}
end_event {
probes = "pci_proc_init%return"
actions = "traceoff"
}
}
}
Here is the example output;
[..]
Hi Masami,
This looks really great! I just got back from a 10 day holiday, and I'm
drowning in "catch-up". I plan on looking at all this relatively soon
(in a week or two?). I just don't want you to think I'm ignoring this.
Hi Steve,
Thanks, I hope you enjoyed the holiday!
BTW, this series includes some document update and testcases.
Since we can not decouple these updates, I think it is better you to
pull the series.
Hi Steve and Masami,
selftests patch 8/8 in this series looks good to me. My ack for
it to go through Steve's ftrace tree
Acked-by: Shuah Khan
thanks,
-- Shuah
Re: [PATCH v3 0/8] tracing/boot: Add new options for tracing specific period
On Thu, 10 Sep 2020 19:34:33 -0400
Steven Rostedt wrote:
> On Thu, 10 Sep 2020 17:54:54 +0900
> Masami Hiramatsu wrote:
>
> > Hi,
> >
> > Here is the 3rd version of the series to improve the boot-time tracing to
> > support kretprobe and tracing_on option. Previous version is here:
> >
> >
> > https://lkml.kernel.org/r/159894698993.1478826.2813843560314595660.stgit@devnote2
> >
> > This version adds uprobe %return suffix support ([5/8]) and the testcases
> > ([8/8]), and update kprobe %suffix support([4/8]) and the uprobe event
> > document([6/8]).
> >
> >
> > The combination of tracing_on and kretprobe allows us to trace events
> > while a specific function call period. For example, the below bootconfig
> > will make a function callgraph in the pci_proc_init() function at boot
> > time.
> >
> > ftrace {
> > tracing_on = 0 # off at start
> > tracer = function_graph
> > event.kprobes {
> > start_event {
> > probes = "pci_proc_init"
> > actions = "traceon"
> > }
> > end_event {
> > probes = "pci_proc_init%return"
> > actions = "traceoff"
> > }
> > }
> > }
> >
> > Here is the example output;
> >
>
> [..]
>
> Hi Masami,
>
> This looks really great! I just got back from a 10 day holiday, and I'm
> drowning in "catch-up". I plan on looking at all this relatively soon
> (in a week or two?). I just don't want you to think I'm ignoring this.
Hi Steve,
Thanks, I hope you enjoyed the holiday!
BTW, this series includes some document update and testcases.
Since we can not decouple these updates, I think it is better you to
pull the series.
Regards,
--
Masami Hiramatsu
Re: [PATCH v3 0/8] tracing/boot: Add new options for tracing specific period
On Thu, 10 Sep 2020 17:54:54 +0900
Masami Hiramatsu wrote:
> Hi,
>
> Here is the 3rd version of the series to improve the boot-time tracing to
> support kretprobe and tracing_on option. Previous version is here:
>
>
> https://lkml.kernel.org/r/159894698993.1478826.2813843560314595660.stgit@devnote2
>
> This version adds uprobe %return suffix support ([5/8]) and the testcases
> ([8/8]), and update kprobe %suffix support([4/8]) and the uprobe event
> document([6/8]).
>
>
> The combination of tracing_on and kretprobe allows us to trace events
> while a specific function call period. For example, the below bootconfig
> will make a function callgraph in the pci_proc_init() function at boot
> time.
>
> ftrace {
> tracing_on = 0 # off at start
> tracer = function_graph
> event.kprobes {
> start_event {
> probes = "pci_proc_init"
> actions = "traceon"
> }
> end_event {
> probes = "pci_proc_init%return"
> actions = "traceoff"
> }
> }
> }
>
> Here is the example output;
>
[..]
Hi Masami,
This looks really great! I just got back from a 10 day holiday, and I'm
drowning in "catch-up". I plan on looking at all this relatively soon
(in a week or two?). I just don't want you to think I'm ignoring this.
-- Steve
[PATCH v3 0/8] tracing/boot: Add new options for tracing specific period
Hi,
Here is the 3rd version of the series to improve the boot-time tracing to
support kretprobe and tracing_on option. Previous version is here:
https://lkml.kernel.org/r/159894698993.1478826.2813843560314595660.stgit@devnote2
This version adds uprobe %return suffix support ([5/8]) and the testcases
([8/8]), and update kprobe %suffix support([4/8]) and the uprobe event
document([6/8]).
The combination of tracing_on and kretprobe allows us to trace events
while a specific function call period. For example, the below bootconfig
will make a function callgraph in the pci_proc_init() function at boot
time.
ftrace {
tracing_on = 0 # off at start
tracer = function_graph
event.kprobes {
start_event {
probes = "pci_proc_init"
actions = "traceon"
}
end_event {
probes = "pci_proc_init%return"
actions = "traceoff"
}
}
}
Here is the example output;
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
0) | pci_proc_init() {
0) |proc_mkdir() {
0) | proc_mkdir_data() {
0) |__proc_create() {
0) | _raw_read_lock() {
0) 0.179 us|preempt_count_add();
0) 0.203 us|do_raw_read_lock();
0) 1.210 us| }
0) | __xlate_proc_name() {
0) 0.449 us|pde_subdir_find();
0) 0.913 us| }
0) | _raw_read_unlock() {
0) 0.169 us|do_raw_read_unlock();
0) 0.175 us|preempt_count_sub();
0) 0.841 us| }
0) | kmem_cache_alloc() {
0) |fs_reclaim_acquire() {
0) 0.154 us| __need_fs_reclaim();
0) 0.240 us| fs_reclaim_acquire.part.0();
0) 0.889 us|}
0) |fs_reclaim_release() {
0) 0.174 us| __need_fs_reclaim();
0) 0.516 us|}
0) 0.157 us|should_failslab();
0) |rcu_read_lock_sched_held() {
0) | rcu_read_lock_held_common() {
0) 0.156 us|rcu_is_watching();
0) 0.158 us|rcu_lockdep_current_cpu_online();
0) 0.735 us| }
0) 1.054 us|}
0) 3.407 us| }
0) 0.168 us| __raw_spin_lock_init();
0) 7.575 us|}
0) |proc_register() {
0) | _raw_spin_lock_irqsave() {
0) 0.187 us|preempt_count_add();
...
Thank you,
---
Masami Hiramatsu (8):
kprobes: tracing/kprobes: Fix to kill kprobes on initmem after boot
tracing/boot: Add per-instance tracing_on option support
Documentation: tracing: Add tracing_on option to boot-time tracer
tracing/kprobes: Support perf-style return probe
tracing/uprobes: Support perf-style return probe
Documentation: tracing: Add %return suffix description
Documentation: tracing: boot: Add an example of tracing function-calls
selftests/ftrace: Add %return suffix tests
Documentation/trace/boottime-trace.rst | 24
Documentation/trace/kprobetrace.rst|2 ++
Documentation/trace/uprobetracer.rst |2 ++
include/linux/kprobes.h|5
init/main.c|2 ++
kernel/kprobes.c | 22 ++
kernel/trace/trace.c |4 ++-
kernel/trace/trace_boot.c | 10
kernel/trace/trace_kprobe.c| 18 ++-
kernel/trace/trace_probe.h |1 +
kernel/trace/trace_uprobe.c| 15 -
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc |6 +
.../test.d/kprobe/kretprobe_return_suffix.tc | 21 ++
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc |6 +
14 files changed, 134 insertions(+), 4 deletions(-)
create mode 100644
tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_return_suffix.tc
--
Masami Hiramatsu (Linaro)
