From: K Prateek Nayak <kprateek.nayak@amd.com>
To: Shrikanth Hegde <sshegde@linux.ibm.com>,
Naman Jain <namjain@linux.microsoft.com>
Cc: <stable@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
Steve Wahl <steve.wahl@hpe.com>,
Saurabh Singh Sengar <ssengar@linux.microsoft.com>,
<srivatsa@csail.mit.edu>, Michael Kelley <mhklinux@outlook.com>,
Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
Valentin Schneider <vschneid@redhat.com>
Subject: Re: [PATCH v3] sched/topology: Enable topology_span_sane check only for debug builds
Date: Tue, 11 Feb 2025 16:26:40 +0530 [thread overview]
Message-ID: <0f51023c-7413-4503-95d4-42113fa3e2e4@amd.com> (raw)
In-Reply-To: <ef199f2a-f970-4c86-a3f2-ddb6ad7abc96@linux.ibm.com>
Hello Shrikanth,
On 2/11/2025 11:22 AM, Shrikanth Hegde wrote:
>
> [..snip..]
>>
>> What I'm getting to is that the arch specific topology parsing code
>> can set a "SDTL_ARCH_VERIFIED" flag indicating that the arch specific
>> bits have verified that the cpumasks are either equal or disjoint and
>> since sched_debug() is "false" by default, topology_span_sane() can
>> bail out if:
>>
>> if (!sched_debug() && (tl->flags & SDTL_ARCH_VERIFIED))
>> return;
>>
>
> it would simpler to use sched_debug(). no?
>
> Since it can be enabled at runtime by "echo Y > verbose", if one one needs to enable even after boot. Wouldn't that suffice to run topology_span_sane by doing a hotplug?
Ack! It was a suggestion in case folks felt apprehensive about guarding
the check behind sched_debug() ...
>
>> In case arch specific parsing was wrong, "sched_verbose" can always
>> be used to double check the topology and for the arch that require
>> this sanity check, Steve's optimized version of
>> topology_span_sane() can be run to be sure of the sanity.
>>
>> All this justification is in case folks want to keep
>> topology_span_sane() around but if no one cares, Naman and Saurabh's
>> approach works as intended.
... which is why I ended that long explanation with this :)
Valentin seems to be on board with the current approach from Naman and
Saurabh and it works as intended.
>>
>
--
Thanks and Regards,
Prateek
prev parent reply other threads:[~2025-02-11 10:56 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-02-03 11:47 [PATCH v3] sched/topology: Enable topology_span_sane check only for debug builds Naman Jain
2025-02-05 7:20 ` K Prateek Nayak
2025-02-05 7:23 ` Naman Jain
2025-02-10 9:53 ` Naman Jain
2025-02-05 9:48 ` K Prateek Nayak
2025-02-05 9:55 ` Peter Zijlstra
2025-02-05 10:13 ` K Prateek Nayak
2025-02-05 10:16 ` Peter Zijlstra
2025-02-06 9:10 ` K Prateek Nayak
2025-02-06 9:47 ` Naman Jain
2025-02-06 10:19 ` K Prateek Nayak
2025-02-06 10:55 ` Naman Jain
2025-02-06 15:24 ` Valentin Schneider
2025-02-06 15:30 ` Steve Wahl
2025-02-06 17:18 ` Naman Jain
2025-02-07 2:44 ` K Prateek Nayak
2025-02-11 5:52 ` Shrikanth Hegde
2025-02-11 7:06 ` Naman Jain
2025-02-11 10:56 ` K Prateek Nayak [this message]
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=0f51023c-7413-4503-95d4-42113fa3e2e4@amd.com \
--to=kprateek.nayak@amd.com \
--cc=bsegall@google.com \
--cc=dietmar.eggemann@arm.com \
--cc=juri.lelli@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mgorman@suse.de \
--cc=mhklinux@outlook.com \
--cc=mingo@redhat.com \
--cc=namjain@linux.microsoft.com \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=srivatsa@csail.mit.edu \
--cc=ssengar@linux.microsoft.com \
--cc=sshegde@linux.ibm.com \
--cc=stable@vger.kernel.org \
--cc=steve.wahl@hpe.com \
--cc=vincent.guittot@linaro.org \
--cc=vschneid@redhat.com \
/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