Re: [PATCH 10/20] perf data: Add directory support

[Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>]

Em Sun, Feb 24, 2019 at 08:06:46PM +0100, Jiri Olsa escreveu:
> Adding support to have directory as perf.data.
> 
> The caller needs to set 'struct perf_data::is_dir flag
> and the path will be treated as directory.
> 
> The 'struct perf_data::file' is initialized and open
> as 'path/header' file.
> 
> Adding check to direcory interface functions to check
> on is_dir flag.
> 
> Link: http://lkml.kernel.org/n/tip-pvot1aywiem9epgqpfi1agaj@git.kernel.org
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
>  tools/perf/util/data.c    | 41 ++++++++++++++++++++++++++++++++++++++-
>  tools/perf/util/data.h    |  6 ++++++
>  tools/perf/util/session.c |  4 ++++
>  3 files changed, 50 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c
> index 7bd5ddeb7a41..72ac4dbb5c69 100644
> --- a/tools/perf/util/data.c
> +++ b/tools/perf/util/data.c
> @@ -34,6 +34,9 @@ int perf_data__create_dir(struct perf_data *data, int nr)
>  	struct perf_data_file *files = NULL;
>  	int i, ret = -1;
>  
> +	if (WARN_ON(!data->is_dir))
> +		return -EINVAL;
> +
>  	files = zalloc(nr * sizeof(*files));
>  	if (!files)
>  		return -ENOMEM;
> @@ -69,6 +72,9 @@ int perf_data__open_dir(struct perf_data *data)
>  	DIR *dir;
>  	int nr = 0;
>  
> +	if (WARN_ON(!data->is_dir))
> +		return -EINVAL;
> +
>  	dir = opendir(data->path);
>  	if (!dir)
>  		return -EINVAL;
> @@ -173,6 +179,16 @@ static int check_backup(struct perf_data *data)
>  	return 0;
>  }
>  
> +static bool is_dir(struct perf_data *data)
> +{
> +	struct stat st;
> +
> +	if (stat(data->path, &st))
> +		return false;
> +
> +	return (st.st_mode & S_IFMT) == S_IFDIR;
> +}
> +
>  static int open_file_read(struct perf_data *data)
>  {
>  	struct stat st;
> @@ -254,6 +270,22 @@ static int open_file_dup(struct perf_data *data)
>  	return open_file(data);
>  }
>  
> +static int open_dir(struct perf_data *data)
> +{
> +	if (perf_data__is_write(data) &&
> +	    mkdir(data->path, S_IRWXU) < 0)
> +		return -1;
> +
> +	/*
> +	 * So far we open only the header, so we
> +	 * can read the data version and layout.
> +	 */
> +	if (asprintf(&data->file.path, "%s/header", data->path) < 0)
> +		return -ENOMEM;

so, if this fails, then we should unwind the mkdir, if it was
performed, so that we leave things as they were before calling
open_dir(), right?

I processed everything up to here.

- Arnaldo

> +
> +	return open_file(data);
> +}
> +
>  int perf_data__open(struct perf_data *data)
>  {
>  	if (check_pipe(data))
> @@ -265,11 +297,18 @@ int perf_data__open(struct perf_data *data)
>  	if (check_backup(data))
>  		return -1;
>  
> -	return open_file_dup(data);
> +	if (perf_data__is_read(data))
> +		data->is_dir = is_dir(data);
> +
> +	return perf_data__is_dir(data) ?
> +	       open_dir(data) : open_file_dup(data);
>  }
>  
>  void perf_data__close(struct perf_data *data)
>  {
> +	if (perf_data__is_dir(data))
> +		perf_data__close_dir(data);
> +
>  	free(data->file.path);
>  	close(data->file.fd);
>  }
> diff --git a/tools/perf/util/data.h b/tools/perf/util/data.h
> index 14b47be2bd69..06aefeda311f 100644
> --- a/tools/perf/util/data.h
> +++ b/tools/perf/util/data.h
> @@ -19,6 +19,7 @@ struct perf_data {
>  	const char		*path;
>  	struct perf_data_file	 file;
>  	bool			 is_pipe;
> +	bool			 is_dir;
>  	bool			 force;
>  	enum perf_data_mode	 mode;
>  
> @@ -43,6 +44,11 @@ static inline int perf_data__is_pipe(struct perf_data *data)
>  	return data->is_pipe;
>  }
>  
> +static inline bool perf_data__is_dir(struct perf_data *data)
> +{
> +	return data->is_dir;
> +}
> +
>  static inline int perf_data__fd(struct perf_data *data)
>  {
>  	return data->file.fd;
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index c764bbc91009..9991e9a8bc12 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -152,6 +152,10 @@ struct perf_session *perf_session__new(struct perf_data *data,
>  			}
>  
>  			perf_evlist__init_trace_event_sample_raw(session->evlist);
> +
> +			/* Open the directory data. */
> +			if (data->is_dir && perf_data__open_dir(data))
> +				goto out_close;
>  		}
>  	} else  {
>  		session->machines.host.env = &perf_env;
> -- 
> 2.17.2

-- 

- Arnaldo