From: Peter Zijlstra <peterz@infradead.org>
To: kan.liang@linux.intel.com
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org,
namhyung@kernel.org, eranian@google.com, ak@linux.intel.com,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] perf/x86/intel/ds: Fix the conversion from TSC to perf time
Date: Mon, 23 Jan 2023 21:39:25 +0100 [thread overview]
Message-ID: <Y87wfaMJ2HLchgap@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20230123172027.125385-1-kan.liang@linux.intel.com>
On Mon, Jan 23, 2023 at 09:20:27AM -0800, kan.liang@linux.intel.com wrote:
> The TSC unstable case seems to be some corner cases (e.g., due to broken
> BIOS). This patch doesn't support the conversion when the TSC is
> unstable. The TSC in a PEBS record will be dropped and fallback to the
> software perf time provided by the generic code.
:-(
You're saying there's modern systems (PEBS timestamps are fairly new)
that trigger unstable TSC ?
What systems in specific have you observed this on -- we really need to
name and shame them, this is fully unacceptable.
next prev parent reply other threads:[~2023-01-23 20:41 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-23 17:20 [PATCH] perf/x86/intel/ds: Fix the conversion from TSC to perf time kan.liang
2023-01-23 20:39 ` Peter Zijlstra [this message]
2023-01-23 21:34 ` Liang, Kan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y87wfaMJ2HLchgap@hirez.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=ak@linux.intel.com \
--cc=eranian@google.com \
--cc=kan.liang@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=namhyung@kernel.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox