linux-kernel - Re: [PATCH v2 5/7] perf evlist: Skip dummy event sample_type check for evlist

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <5797e5a7-a85f-4f7c-1649-88f8f9ff7a6b@intel.com>
Date:   Mon, 17 Jul 2023 17:41:24 +0300
From:   Adrian Hunter <adrian.hunter@...el.com>
To:     Yang Jihong <yangjihong1@...wei.com>, peterz@...radead.org,
        mingo@...hat.com, acme@...nel.org, mark.rutland@....com,
        alexander.shishkin@...ux.intel.com, jolsa@...nel.org,
        namhyung@...nel.org, irogers@...gle.com, kan.liang@...ux.intel.com,
        james.clark@....com, tmricht@...ux.ibm.com, ak@...ux.intel.com,
        anshuman.khandual@....com, linux-kernel@...r.kernel.org,
        linux-perf-users@...r.kernel.org
Subject: Re: [PATCH v2 5/7] perf evlist: Skip dummy event sample_type check
 for evlist_config

On 15/07/23 06:29, Yang Jihong wrote:
> The dummp event does not contain sampls data. Therefore, sample_type does
> not need to be checked.
> 
> Currently, the sample id format of the actual sampling event may be changed
> after the dummy event is added.
> 
> Signed-off-by: Yang Jihong <yangjihong1@...wei.com>
> ---
>  tools/perf/util/record.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c
> index 9eb5c6a08999..0240be3b340f 100644
> --- a/tools/perf/util/record.c
> +++ b/tools/perf/util/record.c
> @@ -128,6 +128,13 @@ void evlist__config(struct evlist *evlist, struct record_opts *opts, struct call
>  		evlist__for_each_entry(evlist, evsel) {
>  			if (evsel->core.attr.sample_type == first->core.attr.sample_type)
>  				continue;
> +
> +			/*
> +			 * Skip the sample_type check for the dummy event
> +			 * because it does not have any samples anyway.
> +			 */
> +			if (evsel__is_dummy_event(evsel))
> +				continue;

Sideband event records have "ID samples" so the sample type still matters.


>  			use_sample_identifier = perf_can_sample_identifier();
>  			break;
>  		}