linux-kernel - Re: [PATCH 1/3] perf ftrace: Fix latency stats with BPF

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] [day] [month] [year] [list]

Message-Id: <174188337460.3466761.2196877504904331124.b4-ty@kernel.org>
Date: Thu, 13 Mar 2025 09:29:34 -0700
From: Namhyung Kim <namhyung@...nel.org>
To: Arnaldo Carvalho de Melo <acme@...nel.org>, 
 Ian Rogers <irogers@...gle.com>, Kan Liang <kan.liang@...ux.intel.com>, 
 Namhyung Kim <namhyung@...nel.org>
Cc: Jiri Olsa <jolsa@...nel.org>, Adrian Hunter <adrian.hunter@...el.com>, 
 Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...nel.org>, 
 LKML <linux-kernel@...r.kernel.org>, linux-perf-users@...r.kernel.org, 
 bpf@...r.kernel.org, Gabriele Monaco <gmonaco@...hat.com>
Subject: Re: [PATCH 1/3] perf ftrace: Fix latency stats with BPF

On Thu, 27 Feb 2025 11:12:21 -0800, Namhyung Kim wrote:
> When BPF collects the stats for the latency in usec, it first divides
> the time by 1000.  But that means it would have 0 if the delta is small
> and won't update the total time properly.
> 
> Let's keep the stats in nsec always and adjust to usec before printing.
> 
> Before:
> 
> [...]
Applied to perf-tools-next, thanks!

Best regards,
Namhyung