When in TUI mode, it is impossible to show all the debug messages to
console. This make it hard to debug perf issues using debug messages.
This patch adds support for logging debug messages to file to resolve
this problem.
The usage is:
perf -debug verbose=2 --debug file=1 COMMAND
And the path of log file is '~/perf.log'.
Signed-off-by: Changbin Du <[email protected]>
---
tools/perf/Documentation/perf.txt | 4 +++-
tools/perf/util/debug.c | 20 ++++++++++++++++++++
2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/tools/perf/Documentation/perf.txt b/tools/perf/Documentation/perf.txt
index 401f0ed67439..45db7b22d1a5 100644
--- a/tools/perf/Documentation/perf.txt
+++ b/tools/perf/Documentation/perf.txt
@@ -16,7 +16,8 @@ OPTIONS
Setup debug variable (see list below) in value
range (0, 10). Use like:
--debug verbose # sets verbose = 1
- --debug verbose=2 # sets verbose = 2
+ --debug verbose=2 --debug file=1
+ # sets verbose = 2 and save log to file
List of debug variables allowed to set:
verbose - general debug messages
@@ -24,6 +25,7 @@ OPTIONS
data-convert - data convert command debug messages
stderr - write debug output (option -v) to stderr
in browser mode
+ file - write debug output to log file ~/perf.log
--buildid-dir::
Setup buildid cache directory. It has higher priority than
diff --git a/tools/perf/util/debug.c b/tools/perf/util/debug.c
index 3780fe42453b..f0b4346a0efa 100644
--- a/tools/perf/util/debug.c
+++ b/tools/perf/util/debug.c
@@ -8,6 +8,7 @@
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
+#include <errno.h>
#include <sys/wait.h>
#include <api/debug.h>
#include <linux/time64.h>
@@ -28,6 +29,8 @@ int verbose;
bool dump_trace = false, quiet = false;
int debug_ordered_events;
static int redirect_to_stderr;
+static int log_to_file;
+static FILE *log_file;
int debug_data_convert;
int veprintf(int level, int var, const char *fmt, va_list args)
@@ -39,6 +42,9 @@ int veprintf(int level, int var, const char *fmt, va_list args)
ui_helpline__vshow(fmt, args);
else
ret = vfprintf(stderr, fmt, args);
+
+ if (log_file)
+ vfprintf(log_file, fmt, args);
}
return ret;
@@ -180,6 +186,7 @@ static struct debug_variable {
{ .name = "verbose", .ptr = &verbose },
{ .name = "ordered-events", .ptr = &debug_ordered_events},
{ .name = "stderr", .ptr = &redirect_to_stderr},
+ { .name = "file", .ptr = &log_to_file},
{ .name = "data-convert", .ptr = &debug_data_convert },
{ .name = NULL, }
};
@@ -219,6 +226,19 @@ int perf_debug_option(const char *str)
v = -1;
*var->ptr = v;
+
+ if (log_to_file) {
+ char log_path[PATH_MAX];
+
+ strcat(strcpy(log_path, getenv("HOME")), "/perf.log");
+ log_file = fopen(log_path, "a");
+ if (!log_file) {
+ pr_err("Can not create log file: %s\n", strerror(errno));
+ free(s);
+ return -1;
+ }
+ }
+
free(s);
return 0;
}
--
2.20.1
On Sun, Sep 15, 2019 at 06:27:40PM +0800, Changbin Du wrote:
> When in TUI mode, it is impossible to show all the debug messages to
> console. This make it hard to debug perf issues using debug messages.
> This patch adds support for logging debug messages to file to resolve
> this problem.
>
> The usage is:
> perf -debug verbose=2 --debug file=1 COMMAND
>
> And the path of log file is '~/perf.log'.
>
> Signed-off-by: Changbin Du <[email protected]>
> ---
> tools/perf/Documentation/perf.txt | 4 +++-
> tools/perf/util/debug.c | 20 ++++++++++++++++++++
> 2 files changed, 23 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/Documentation/perf.txt b/tools/perf/Documentation/perf.txt
> index 401f0ed67439..45db7b22d1a5 100644
> --- a/tools/perf/Documentation/perf.txt
> +++ b/tools/perf/Documentation/perf.txt
> @@ -16,7 +16,8 @@ OPTIONS
> Setup debug variable (see list below) in value
> range (0, 10). Use like:
> --debug verbose # sets verbose = 1
> - --debug verbose=2 # sets verbose = 2
> + --debug verbose=2 --debug file=1
> + # sets verbose = 2 and save log to file
it's variable already, why not allow to pass the path directly like:
--debug file=~/perf.log
would be great if we won't need to use --debug twice and allow:
--debug verbose=2,file=perf.log
jirka
On Fri, Sep 20, 2019 at 10:53:56PM +0200, Jiri Olsa wrote:
> On Sun, Sep 15, 2019 at 06:27:40PM +0800, Changbin Du wrote:
> > When in TUI mode, it is impossible to show all the debug messages to
> > console. This make it hard to debug perf issues using debug messages.
> > This patch adds support for logging debug messages to file to resolve
> > this problem.
> >
> > The usage is:
> > perf -debug verbose=2 --debug file=1 COMMAND
> >
> > And the path of log file is '~/perf.log'.
> >
> > Signed-off-by: Changbin Du <[email protected]>
> > ---
> > tools/perf/Documentation/perf.txt | 4 +++-
> > tools/perf/util/debug.c | 20 ++++++++++++++++++++
> > 2 files changed, 23 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/Documentation/perf.txt b/tools/perf/Documentation/perf.txt
> > index 401f0ed67439..45db7b22d1a5 100644
> > --- a/tools/perf/Documentation/perf.txt
> > +++ b/tools/perf/Documentation/perf.txt
> > @@ -16,7 +16,8 @@ OPTIONS
> > Setup debug variable (see list below) in value
> > range (0, 10). Use like:
> > --debug verbose # sets verbose = 1
> > - --debug verbose=2 # sets verbose = 2
> > + --debug verbose=2 --debug file=1
> > + # sets verbose = 2 and save log to file
>
> it's variable already, why not allow to pass the path directly like:
>
> --debug file=~/perf.log
>
> would be great if we won't need to use --debug twice and allow:
>
> --debug verbose=2,file=perf.log
>
This could be done, but first we need to change the option parsing code
first. will do it later.
> jirka
--
Cheers,
Changbin Du