[PATCH v6 00/17] perf: ftrace enhancement

[PATCH v6 00/17] perf: ftrace enhancement

[Changbin Du]

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 perf.

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:

$ sudo perf ftrace -h

 Usage: perf ftrace [<options>] [<command>]
    or: perf ftrace [<options>] -- <command> [<options>]

    -a, --all-cpus        system-wide collection from all CPUs
    -C, --cpu <cpu>       list of cpus to monitor
    -D, --delay <n>       ms to wait before starting tracing after program start
    -F, --funcs           Show available functions to filter
    -G, --graph-funcs <func>
                          trace given functions using function_graph tracer
    -g, --nograph-funcs <func>
                          Set nograph filter on given functions
    -m, --buffer-size <size>
                          size of per cpu buffer
    -N, --notrace-funcs <func>
                          do not trace given functions
    -p, --pid <pid>       trace on existing process id
    -T, --trace-funcs <func>
                          trace given functions using function tracer
    -t, --tracer <tracer>
                          tracer to use: function or function_graph (This option is deprecated)
    -v, --verbose         be more verbose
        --func-opts <options>
                          function tracer options, available options: call-graph,irq-info
        --graph-opts <options>
                          graph tracer options, available options: nosleep-time,noirqs,verbose,thresh=<n>,depth=<n>
        --inherit         trace children processes

v6:
  o fix return value of read_tracing_file_to_stdout().
  o make __cmd_ftrace() shorter.
  o remove option '-t, --tid <tid>'.
v5:
  o trivial fixes.
v4:
  o add util/parse-sublevel-options.c
  O remove -D/--graph-depth
v3:
  o add --func-opts and --graph-opts to set tracer specific options.
  o support units as a suffix for option '-m/--buffer-size'.
v2:
  o patches for option '-u/--userstacktrace' and '--no-pager' are dropped.
  o update all related perf documentation.
  o rename some options. Now all funcgraph tracer options are prefixed with
    '--graph-', while all function tracer options are prefixed with '--func-'.
  o mark old options deprecated instead of removing them.


Changbin Du (17):
  perf ftrace: select function/function_graph tracer automatically
  perf ftrace: add option '-F/--funcs' to list available functions
  perf ftrace: factor out function write_tracing_file_int()
  perf ftrace: add option '-m/--buffer-size' to set per-cpu buffer size
  perf ftrace: show trace column header
  perf ftrace: add option '--inherit' to trace children processes
  perf: util: add general function to parse sublevel options
  perf ftrace: add support for tracing option 'func_stack_trace'
  perf ftrace: add support for trace option sleep-time
  perf ftrace: add support for trace option funcgraph-irqs
  perf ftrace: add support for tracing option 'irq-info'
  perf ftrace: add option 'verbose' to show more info for graph tracer
  perf ftrace: add support for trace option tracing_thresh
  perf: ftrace: allow set graph depth by '--graph-opts'
  perf ftrace: add option -D/--delay to delay tracing
  perf: ftrace: Add set_tracing_options() to set all trace options
  perf ftrace: add change log

 tools/perf/Documentation/perf-config.txt |   5 -
 tools/perf/Documentation/perf-ftrace.txt |  33 +-
 tools/perf/builtin-ftrace.c              | 412 +++++++++++++++++++++--
 tools/perf/util/Build                    |   1 +
 tools/perf/util/debug.c                  |  61 +---
 tools/perf/util/parse-sublevel-options.c |  70 ++++
 tools/perf/util/parse-sublevel-options.h |  11 +
 7 files changed, 507 insertions(+), 86 deletions(-)
 create mode 100644 tools/perf/util/parse-sublevel-options.c
 create mode 100644 tools/perf/util/parse-sublevel-options.h

-- 
2.25.1

[PATCH v6 01/17] perf ftrace: select function/function_graph tracer automatically

[Changbin Du]

The '-g/-G' options have already implied function_graph tracer should be
used instead of function tracer. So the extra option '--tracer' can be
killed.

This patch changes the behavior as below:
  - By default, function tracer is used.
  - If '-g' or '-G' option is on, then function_graph tracer is used.
  - The perf configuration item 'ftrace.tracer' is marked as deprecated.
  - The option '--tracer' is marked as deprecated.

Here are some examples.

This will start tracing all functions using function tracer:
  $ sudo perf ftrace

This will trace all functions using function graph tracer:
  $ sudo perf ftrace -G '*'

This will trace function vfs_read using function graph tracer:
  $ sudo perf ftrace -G vfs_read

Signed-off-by: Changbin Du <changbin.du@gmail.com>

---
v3: remove default '*' for -G/-T.
---
 tools/perf/Documentation/perf-config.txt |  5 -----
 tools/perf/Documentation/perf-ftrace.txt |  2 +-
 tools/perf/builtin-ftrace.c              | 15 ++++++++++-----
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/tools/perf/Documentation/perf-config.txt b/tools/perf/Documentation/perf-config.txt
index c7d3df5798e2..a25fee7de3b2 100644
--- a/tools/perf/Documentation/perf-config.txt
+++ b/tools/perf/Documentation/perf-config.txt
@@ -612,11 +612,6 @@ trace.*::
 		"libbeauty", the default, to use the same argument beautifiers used in the
 		strace-like sys_enter+sys_exit lines.
 
-ftrace.*::
-	ftrace.tracer::
-		Can be used to select the default tracer. Possible values are
-		'function' and 'function_graph'.
-
 llvm.*::
 	llvm.clang-path::
 		Path to clang. If omit, search it from $PATH.
diff --git a/tools/perf/Documentation/perf-ftrace.txt b/tools/perf/Documentation/perf-ftrace.txt
index b80c84307dc9..952e46669168 100644
--- a/tools/perf/Documentation/perf-ftrace.txt
+++ b/tools/perf/Documentation/perf-ftrace.txt
@@ -24,7 +24,7 @@ OPTIONS
 
 -t::
 --tracer=::
-	Tracer to use: function_graph or function.
+	Tracer to use: function_graph or function. This option is deprecated.
 
 -v::
 --verbose=::
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 2bfc1b0db536..5f53da87040d 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -27,7 +27,6 @@
 #include "util/cap.h"
 #include "util/config.h"
 
-#define DEFAULT_TRACER  "function_graph"
 
 struct perf_ftrace {
 	struct evlist		*evlist;
@@ -419,6 +418,7 @@ static int perf_ftrace_config(const char *var, const char *value, void *cb)
 	if (strcmp(var, "ftrace.tracer"))
 		return -1;
 
+	pr_warning("Configuration ftrace.tracer is deprecated\n");
 	if (!strcmp(value, "function_graph") ||
 	    !strcmp(value, "function")) {
 		ftrace->tracer = value;
@@ -459,7 +459,7 @@ int cmd_ftrace(int argc, const char **argv)
 {
 	int ret;
 	struct perf_ftrace ftrace = {
-		.tracer = DEFAULT_TRACER,
+		.tracer = "function",
 		.target = { .uid = UINT_MAX, },
 	};
 	const char * const ftrace_usage[] = {
@@ -469,7 +469,7 @@ int cmd_ftrace(int argc, const char **argv)
 	};
 	const struct option ftrace_options[] = {
 	OPT_STRING('t', "tracer", &ftrace.tracer, "tracer",
-		   "tracer to use: function_graph(default) or function"),
+		   "tracer to use: function or function_graph (This option is deprecated)"),
 	OPT_STRING('p', "pid", &ftrace.target.pid, "pid",
 		   "trace on existing process id"),
 	OPT_INCR('v', "verbose", &verbose,
@@ -479,11 +479,13 @@ int cmd_ftrace(int argc, const char **argv)
 	OPT_STRING('C', "cpu", &ftrace.target.cpu_list, "cpu",
 		    "list of cpus to monitor"),
 	OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
-		     "trace given functions only", parse_filter_func),
+		     "trace given functions using function tracer",
+		     parse_filter_func),
 	OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func",
 		     "do not trace given functions", parse_filter_func),
 	OPT_CALLBACK('G', "graph-funcs", &ftrace.graph_funcs, "func",
-		     "Set graph filter on given functions", parse_filter_func),
+		     "trace given functions using function_graph tracer",
+		     parse_filter_func),
 	OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func",
 		     "Set nograph filter on given functions", parse_filter_func),
 	OPT_INTEGER('D', "graph-depth", &ftrace.graph_depth,
@@ -505,6 +507,9 @@ int cmd_ftrace(int argc, const char **argv)
 	if (!argc && target__none(&ftrace.target))
 		ftrace.target.system_wide = true;
 
+	if (!list_empty(&ftrace.graph_funcs) || !list_empty(&ftrace.nograph_funcs))
+		ftrace.tracer = "function_graph";
+
 	ret = target__validate(&ftrace.target);
 	if (ret) {
 		char errbuf[512];
-- 
2.25.1

[PATCH v6 00/17] perf: ftrace enhancement

[Changbin Du]

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 perf.

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:

$ sudo perf ftrace -h

 Usage: perf ftrace [<options>] [<command>]
    or: perf ftrace [<options>] -- <command> [<options>]

    -a, --all-cpus        system-wide collection from all CPUs
    -C, --cpu <cpu>       list of cpus to monitor
    -D, --delay <n>       ms to wait before starting tracing after program start
    -F, --funcs           Show available functions to filter
    -G, --graph-funcs <func>
                          trace given functions using function_graph tracer
    -g, --nograph-funcs <func>
                          Set nograph filter on given functions
    -m, --buffer-size <size>
                          size of per cpu buffer
    -N, --notrace-funcs <func>
                          do not trace given functions
    -p, --pid <pid>       trace on existing process id
    -T, --trace-funcs <func>
                          trace given functions using function tracer
    -t, --tracer <tracer>
                          tracer to use: function or function_graph (This option is deprecated)
    -v, --verbose         be more verbose
        --func-opts <options>
                          function tracer options, available options: call-graph,irq-info
        --graph-opts <options>
                          graph tracer options, available options: nosleep-time,noirqs,verbose,thresh=<n>,depth=<n>
        --inherit         trace children processes

v6:
  o fix return value of read_tracing_file_to_stdout().
  o make __cmd_ftrace() shorter.
  o remove option '-t, --tid <tid>'.
v5:
  o trivial fixes.
v4:
  o add util/parse-sublevel-options.c
  O remove -D/--graph-depth
v3:
  o add --func-opts and --graph-opts to set tracer specific options.
  o support units as a suffix for option '-m/--buffer-size'.
v2:
  o patches for option '-u/--userstacktrace' and '--no-pager' are dropped.
  o update all related perf documentation.
  o rename some options. Now all funcgraph tracer options are prefixed with
    '--graph-', while all function tracer options are prefixed with '--func-'.
  o mark old options deprecated instead of removing them.


Changbin Du (17):
  perf ftrace: select function/function_graph tracer automatically
  perf ftrace: add option '-F/--funcs' to list available functions
  perf ftrace: factor out function write_tracing_file_int()
  perf ftrace: add option '-m/--buffer-size' to set per-cpu buffer size
  perf ftrace: show trace column header
  perf ftrace: add option '--inherit' to trace children processes
  perf: util: add general function to parse sublevel options
  perf ftrace: add support for tracing option 'func_stack_trace'
  perf ftrace: add support for trace option sleep-time
  perf ftrace: add support for trace option funcgraph-irqs
  perf ftrace: add support for tracing option 'irq-info'
  perf ftrace: add option 'verbose' to show more info for graph tracer
  perf ftrace: add support for trace option tracing_thresh
  perf: ftrace: allow set graph depth by '--graph-opts'
  perf ftrace: add option -D/--delay to delay tracing
  perf: ftrace: Add set_tracing_options() to set all trace options
  perf ftrace: add change log

 tools/perf/Documentation/perf-config.txt |   5 -
 tools/perf/Documentation/perf-ftrace.txt |  33 +-
 tools/perf/builtin-ftrace.c              | 412 +++++++++++++++++++++--
 tools/perf/util/Build                    |   1 +
 tools/perf/util/debug.c                  |  61 +---
 tools/perf/util/parse-sublevel-options.c |  70 ++++
 tools/perf/util/parse-sublevel-options.h |  11 +
 7 files changed, 507 insertions(+), 86 deletions(-)
 create mode 100644 tools/perf/util/parse-sublevel-options.c
 create mode 100644 tools/perf/util/parse-sublevel-options.h

-- 
2.25.1