Re: [PATCH v8 21/22] perf session: Introduce READER_NODATA state

["Bayduraev, Alexey V" <alexey.v.bayduraev@linux.intel.com>]

Hi,

On 30.06.2021 18:55, Alexey Bayduraev wrote:
> Adding READER_NODATA state to differentiate it from the real end-of-file
> state. Also an indent depth in reades initialization loop is reduced.

Just a little note: I will squash this patch to 19 and 20.

Regards,
Alexey

> 
> Suggested-by: Namhyung Kim <namhyung@gmail.com>
> Signed-off-by: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
> ---
>  tools/perf/util/session.c | 45 ++++++++++++++++++++-------------------
>  1 file changed, 23 insertions(+), 22 deletions(-)
> 
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index b11a502c22a3..c2b6c5f4e119 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -70,7 +70,8 @@ struct reader_state {
>  
>  enum {
>  	READER_EOF	=  0,
> -	READER_OK	=  1,
> +	READER_NODATA	=  1,
> +	READER_OK	=  2,
>  };
>  
>  struct reader {
> @@ -2305,7 +2306,7 @@ reader__read_event(struct reader *rd, struct perf_session *session,
>  		return PTR_ERR(event);
>  
>  	if (!event)
> -		return READER_EOF;
> +		return READER_NODATA;
>  
>  	session->active_reader = rd;
>  	size = event->header.size;
> @@ -2395,7 +2396,7 @@ static int __perf_session__process_events(struct perf_session *session)
>  		err = reader__read_event(rd, session, &prog);
>  		if (err < 0)
>  			break;
> -		if (err == READER_EOF) {
> +		if (err == READER_NODATA) {
>  			err = reader__mmap(rd, session);
>  			if (err <= 0)
>  				break;
> @@ -2472,25 +2473,25 @@ static int __perf_session__process_dir_events(struct perf_session *session)
>  	readers++;
>  
>  	for (i = 0; i < data->dir.nr; i++) {
> -		if (data->dir.files[i].size) {
> -			rd[readers] = (struct reader) {
> -				.fd		 = data->dir.files[i].fd,
> -				.path		 = data->dir.files[i].path,
> -				.data_size	 = data->dir.files[i].size,
> -				.data_offset	 = 0,
> -				.in_place_update = session->data->in_place_update,
> -			};
> -			ret = reader__init(&rd[readers], NULL);
> -			if (ret)
> -				goto out_err;
> -			ret = reader__mmap(&rd[readers], session);
> -			if (ret != READER_OK) {
> -				if (ret == READER_EOF)
> -					ret = -EINVAL;
> -				goto out_err;
> -			}
> -			readers++;
> +		if (!data->dir.files[i].size)
> +			continue;
> +		rd[readers] = (struct reader) {
> +			.fd		 = data->dir.files[i].fd,
> +			.path		 = data->dir.files[i].path,
> +			.data_size	 = data->dir.files[i].size,
> +			.data_offset	 = 0,
> +			.in_place_update = session->data->in_place_update,
> +		};
> +		ret = reader__init(&rd[readers], NULL);
> +		if (ret)
> +			goto out_err;
> +		ret = reader__mmap(&rd[readers], session);
> +		if (ret != READER_OK) {
> +			if (ret == READER_EOF)
> +				ret = -EINVAL;
> +			goto out_err;
>  		}
> +		readers++;
>  	}
>  
>  	i = 0;
> @@ -2507,7 +2508,7 @@ static int __perf_session__process_dir_events(struct perf_session *session)
>  		ret = reader__read_event(&rd[i], session, &prog);
>  		if (ret < 0)
>  			break;
> -		if (ret == READER_EOF) {
> +		if (ret == READER_NODATA) {
>  			ret = reader__mmap(&rd[i], session);
>  			if (ret < 0)
>  				goto out_err;
>