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From:   David Howells <dhowells@redhat.com>
In-Reply-To: <CAHk-=whFKL4VuFBWvenG8fAgfvbf36PDgouUSx47rZDWr9BkJw@mail.gmail.com>
References: <CAHk-=whFKL4VuFBWvenG8fAgfvbf36PDgouUSx47rZDWr9BkJw@mail.gmail.com> <2009825.1677229488@warthog.procyon.org.uk> <CAHk-=whAAOVBrzwb2uMjCmdRrtudGesYj0tuqdUgi8X_gbw1jw@mail.gmail.com> <20230220135225.91b0f28344c01d5306c31230@linux-foundation.org> <2134430.1677240738@warthog.procyon.org.uk> <2213409.1677249075@warthog.procyon.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     dhowells@redhat.com, Steve French <stfrench@microsoft.com>,
        Vishal Moola <vishal.moola@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jan Kara <jack@suse.cz>, Paulo Alcantara <pc@cjr.nz>,
        Matthew Wilcox <willy@infradead.org>,
        Huang Ying <ying.huang@intel.com>,
        Baolin Wang <baolin.wang@linux.alibaba.com>,
        Xin Hao <xhao@linux.alibaba.com>, linux-mm@kvack.org,
        mm-commits@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH] cifs: Fix cifs_writepages_region()
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Date:   Fri, 24 Feb 2023 17:19:27 +0000
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Linus Torvalds <torvalds@linux-foundation.org> wrote:

> Can you humor me, and try if just removing that skip count thing
> instead? IOW, this attached patch?

That works too.

> Because that whole "let's stop writing if we need to reschedule" sounds
> truly odd (we have a cond_resched(), although it's per folio batch, not
> per-folio), and the skip count logic doesn't make much sense to me either.

The skip thing, in my code, is only used in WB_SYNC_NONE mode.  If we hit 5
things in progress or rescheduling is required, we return to the caller on the
basis that conflicting flushes appear to be happening in other threads.

David