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Date:   Thu, 29 Jul 2021 16:37:35 +0200
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Christoph Lameter <cl@linux.com>,
        David Rientjes <rientjes@google.com>,
        Pekka Enberg <penberg@kernel.org>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Mel Gorman <mgorman@techsingularity.net>,
        Jesper Dangaard Brouer <brouer@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Jann Horn <jannh@google.com>
Subject: Re: [RFC v2 00/34] SLUB: reduce irq disabled scope and make it RT
 compatible
Message-ID: <20210729143735.wuql2keewd444nvq@linutronix.de>
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On 2021-07-29 16:17:26 [+0200], Vlastimil Babka wrote:
> I forgot to point that out in the cover letter, but with v3 this change to
> raw_spinlock_t is AFAICS no longer possible (at least with
> CONFIG_SLUB_CPU_PARTIAL) because in put_cpu_partial() we now take the local_lock
> and it can be called from get_partial_node() which takes the list_lock.

I saw increased latency numbers with CONFIG_SLUB_CPU_PARTIAL before it
got disabled for other reasons so I'm not too sad if it remains
disabled.

> Hm but SLUB should never call the page allocator from under list_lock in my series?

oh yes. I run into CPU_PARTIAL instead. Sorry for the confusion. So
without PARTIAL it says "24,643 CPUs utilized" and no warnings :)

Sebastian