All of lore.kernel.org
 help / color / mirror / Atom feed
From: Thomas Gleixner <tglx@linutronix.de>
To: Waiman Long <longman@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org, Waiman Long <longman@redhat.com>
Subject: Re: [PATCH v3 2/2] debugobjects: Allow object pool refill mostly in non-atomic context
Date: Thu, 26 Jun 2025 17:22:36 +0200	[thread overview]
Message-ID: <871pr6r0hv.ffs@tglx> (raw)
In-Reply-To: <20250617053527.1223411-3-longman@redhat.com>

On Tue, Jun 17 2025 at 01:35, Waiman Long wrote:
> Removing the pool refill call from the other two may make pool
> exhaustion happen more easily leading to the disabling of the debug
> object tracking.

May is not a technical argument. Why would that happen?

As we established before the only reason why activate() or assert() can
consume an object from the pool is when the object was statically
initialized.

Are there really enough statically initialized objects to actually lead
to pool depletion without that activate/assert hackery?

> As a middle ground, we will allow pool refill from the
> activate and assert_init functions if they are called from a non-atomic
> context which is roughly half of the times depending on the workloads.

Which brings you back to the square one on RT enabled kernels because
the held locks in this circular lock chain scenario do _NOT_ disable
preemption, so in_atomic() evaluates to false ....

Thanks,

        tglx

      parent reply	other threads:[~2025-06-26 15:22 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-17  5:35 [PATCH v3 0/2] debugobjects: Allow object pool refill mostly in non-atomic context Waiman Long
2025-06-17  5:35 ` [PATCH v3 1/2] debugobjects: Show the state of debug_objects_enabled Waiman Long
2025-06-17  5:35 ` [PATCH v3 2/2] debugobjects: Allow object pool refill mostly in non-atomic context Waiman Long
2025-06-24  8:28   ` kernel test robot
2025-06-26 15:22   ` Thomas Gleixner [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=871pr6r0hv.ffs@tglx \
    --to=tglx@linutronix.de \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=longman@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.