Re: [PATCH 06/15] tools lib api: Make tracing_path_strerror_open message generic

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

Em Wed, Sep 02, 2015 at 09:56:36AM +0200, Jiri Olsa escreveu:
> Making tracing_path__strerror_open_tp message generic by mentioning

What means "making message generic"? What is the current behaviour you
think is problematic. what is the new behaviour ad why do you think it
is better?

The test for ENOENT became confusing, i.e. since this was a test for
"tracefs", if debugfs_configured() returned true, i.e. debugfs _was_
found in the system, then, the message makes sense, even if probably
could be made better, i.e. isn't true that if CONFIG_DEBUGFS is
configured and furthermore, debugfs_configure() returns true, then it
should be something like CONFIG_TRACEFS that needs enabling?

I applied all patches before this one, BTW.

- Arnaldo

> both debugfs/tracefs words in error message plus the tracing_path
> instead of debugfs_mountpoint.
> 
> Link: http://lkml.kernel.org/n/tip-5y7nboe2xe619hp649ry58z6@git.kernel.org
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
>  tools/lib/api/fs/tracing_path.c | 20 ++++++++++----------
>  1 file changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/tools/lib/api/fs/tracing_path.c b/tools/lib/api/fs/tracing_path.c
> index 3b3e4f5fc50b..b0ee3b3acef0 100644
> --- a/tools/lib/api/fs/tracing_path.c
> +++ b/tools/lib/api/fs/tracing_path.c
> @@ -90,33 +90,33 @@ static int strerror_open(int err, char *buf, size_t size, const char *filename)
>  
>  	switch (err) {
>  	case ENOENT:
> -		if (debugfs_configured()) {
> +		if (debugfs_configured() || tracefs_configured()) {
>  			snprintf(buf, size,
>  				 "Error:\tFile %s/%s not found.\n"
>  				 "Hint:\tPerhaps this kernel misses some CONFIG_ setting to enable this feature?.\n",
> -				 debugfs_mountpoint, filename);
> +				 tracing_events_path, filename);

Humm

>  			break;
>  		}
>  		snprintf(buf, size, "%s",
> -			 "Error:\tUnable to find debugfs\n"
> -			 "Hint:\tWas your kernel compiled with debugfs support?\n"
> -			 "Hint:\tIs the debugfs filesystem mounted?\n"
> +			 "Error:\tUnable to find debugfs/tracefs\n"
> +			 "Hint:\tWas your kernel compiled with debugfs/tracefs support?\n"
> +			 "Hint:\tIs the debugfs/tracefs filesystem mounted?\n"
>  			 "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'");
>  		break;
>  	case EACCES: {
> -		const char *mountpoint = debugfs_mountpoint;
> +		const char *mountpoint = debugfs_find_mountpoint();
>  
> -		if (!access(debugfs_mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) {
> +		if (!access(mountpoint, R_OK) && strncmp(filename, "tracing/", 8) == 0) {
>  			const char *tracefs_mntpoint = tracefs_find_mountpoint();
>  
>  			if (tracefs_mntpoint)
> -				mountpoint = tracefs_mntpoint;
> +				mountpoint = tracefs_find_mountpoint();
>  		}
>  
>  		snprintf(buf, size,
>  			 "Error:\tNo permissions to read %s/%s\n"
>  			 "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n",
> -			 debugfs_mountpoint, filename, mountpoint);
> +			 tracing_events_path, filename, mountpoint);
>  	}
>  		break;
>  	default:
> @@ -131,7 +131,7 @@ int tracing_path__strerror_open_tp(int err, char *buf, size_t size, const char *
>  {
>  	char path[PATH_MAX];
>  
> -	snprintf(path, PATH_MAX, "tracing/events/%s/%s", sys, name ?: "*");
> +	snprintf(path, PATH_MAX, "%s/%s", sys, name ?: "*");
>  
>  	return strerror_open(err, buf, size, path);
>  }
> -- 
> 2.4.3