Re: [PATCH 00/19] perf: ftrace enhancement

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Sun, May 10, 2020 at 11:06:09PM +0800, Changbin Du escreveu:
> The perf has basic kernel ftrace support but lack support of most tracing
> options. This serias is target to enhance the perf ftrace functionality so
> that we can make full use of kernel ftrace with only perf.

Quite a lot! Going thru it now.

- Arnaldo
 
> In general, this serias be cataloged into two main changes:
>   1) Improve usability of existing functions. For example, we don't need to type
>      extra option to select the tracer.
>   2) Add new options to support all other ftrace functions.
> 
> Here is a glance of all ftrace functions with this serias:
>   * - improved existing options.
>   + - new added options.
> 
> $ sudo perf ftrace -h
> 
>  Usage: perf ftrace [<options>] [<command>]
>     or: perf ftrace [<options>] -- <command> [<options>]
> 
> *   -a, --all-cpus        system-wide collection from all CPUs
> +   -b, --buffer-size <n>
>                           size of per cpu buffer in kb
>     -C, --cpu <cpu>       list of cpus to monitor
> +   -d, --delay <n>       Wait <n> ms before tracing
>     -D, --graph-depth <n>
>                           Max depth for function graph tracer
> *   -G, --graph-funcs <func>
>                           Set graph filter on given functions (imply to use function_graph tracer)
>     -g, --nograph-funcs <func>
>                           Set nograph filter on given functions (imply to use function_graph tracer)
> +   -L, --list-functions  List available functions to filter
> +   -l, --long-info       Show process names, PIDs, timestamps, irq-info if available
>     -N, --notrace-funcs <func>
>                           do not trace given functions
> +   -P, --no-pager        Do not use pager
>     -p, --pid <pid>       trace on existing process id
> +   -s, --func-stack-trace
>                           Show kernel stack trace for function tracer
> +   -t, --tid <tid>       trace on existing thread id (exclusive to --pid)
>     -T, --trace-funcs <func>
>                           trace given functions only
> +   -u, --userstacktrace  Show stacktrace of the current user space thread
>     -v, --verbose         be more verbose
> +       --funcgraph-tail  Show function tails comment (function_graph only)
> +       --latency-format  displays additional information about the latency (function_graph only)
> +       --nofuncgraph-irqs
>                           Ignore functions that happen inside interrupt (function_graph only)
> +       --nosleep-time    Measure on-CPU time only (function_graph only)
> +       --trace-children  Trace children processes
> +       --tracing-thresh <n>
>                           Only show functions of which the duration is greater than <n>µs
> 
> 
> Changbin Du (19):
>   perf ftrace: trace system wide if no target is given
>   perf ftrace: detect workload failure
>   perf ftrace: select function/function_graph tracer automatically
>   perf ftrace: add support for tracing option 'func_stack_trace'
>   perf ftrace: add option '-l/--list-functions' to list available
>     functions
>   perf ftrace: add support for trace option sleep-time
>   perf ftrace: add support for trace option funcgraph-irqs
>   perf ftrace: add option -l/--long-info to show more info
>   perf ftrace: add support for trace option tracing_thresh
>   perf ftrace: add support for trace option funcgraph-tail
>   perf ftrace: add option '-u/--userstacktrace' to show userspace
>     stacktrace
>   perf ftrace: add support for tracing children processes
>   perf ftrace: add option '-b/--buffer-size' to set per-cpu buffer size
>   perf ftrace: add option -P/--no-pager to disable pager
>   perf ftrace: show trace column header
>   perf ftrace: add option -t/--tid to filter by thread id
>   perf ftrace: add option -d/--delay to delay tracing
>   perf ftrace: add option --latency-format to display more info about
>     delay
>   perf ftrace: add change log
> 
>  tools/perf/Documentation/perf-config.txt |   5 -
>  tools/perf/builtin-ftrace.c              | 388 ++++++++++++++++++++---
>  2 files changed, 345 insertions(+), 48 deletions(-)
> 
> -- 
> 2.25.1
> 

-- 

- Arnaldo