| Message ID | 159972809455.428528.4737752126800169128.stgit@devnote2 |
|---|---|
| Headers | show |
| Series | tracing/boot: Add new options for tracing specific period | expand |
On Thu, 10 Sep 2020 17:54:54 +0900 Masami Hiramatsu <mhiramat@kernel.org> 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
On Thu, 10 Sep 2020 19:34:33 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > On Thu, 10 Sep 2020 17:54:54 +0900 > Masami Hiramatsu <mhiramat@kernel.org> 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,
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) <mhiramat@kernel.org>