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Date:   Wed, 15 Sep 2021 13:02:29 -0400
From:   "Theodore Ts'o" <tytso@mit.edu>
To:     NeilBrown <neilb@suse.de>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        "Darrick J. Wong" <djwong@kernel.org>,
        Matthew Wilcox <willy@infradead.org>,
        Mel Gorman <mgorman@suse.com>, linux-xfs@vger.kernel.org,
        linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-nfs@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/6] EXT4: Remove ENOMEM/congestion_wait() loops.
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On Wed, Sep 15, 2021 at 03:25:40PM +1000, NeilBrown wrote:
> Adding gfp_mask to __ext4_journal_start_sb() make perfect sense.
> There doesn't seem much point adding one to __ext4_journal_start(),
> we can have ext4_journal_start_with_revoke() call
> __ext4_journal_start_sb() directly.
> But I cannot see what it doesn't already do that.
> i.e. why have the inline __ext4_journal_start() at all?
> Is it OK if I don't use that for ext4_journal_start_with_revoke()?

Sure.  I think the only reason why we have __ext4_journal_start() as
an inline function at all was for historical reasons.  That is, we
modified __ext4_journal_start() so that it took a struct super, and
instead of changing all of the macros which called
__ext4_journal_start(), we named it to be __ext4_journal_start_sb()
and added the inline definition of __ext4_journal_start() to avoid
changing all of the existing users of __ext4_journal_start().

So sure, it's fine not to use that for
ext4_journal_start_with_revoke(), and we probably should clean up the
use of __ext4_journal_start() at some point.  That's unrelated to your
work, though.

Cheers,

					- Ted