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Date: Tue, 16 Jun 2026 07:28:31 +0200
From: Christoph Hellwig <hch@lst.de>
To: Zorro Lang <zlang@kernel.org>
Cc: fstests@vger.kernel.org
Subject: Re: [PATCH] generic/366: check minimum dio size correctly
Message-ID: <20260616052831.GA23960@lst.de>
References: <20260608070010.1285677-1-hch@lst.de> <ai75PcdwbK7kYBTU@zlang-mailbox> <20260615133331.GA26132@lst.de> <ajBbo5LX-1tk-y3_@zlang-mailbox>
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On Tue, Jun 16, 2026 at 04:13:22AM +0800, Zorro Lang wrote:
> Oh, if we only need to run it once, how about:
> 
> blksz=""
> for (( i = 0; i < $iterations; i++)); do
>     ...
>     if [ -z "$blksz" ];then
> 	    blksz=`$here/src/min_dio_alignment $SCRATCH_MNT $SCRATCH_DEV`
>         if [[ $blksz -gt 512 ]]; then
>             _notrun "512 byte dio alignment required"
>         fi
>     fi
> ...

I can look into it.  But to me this doesn't really seem worth the
effort as calling min_dio_alignment is so cheap compared to the
mount/unmount cycle never mind everything else we do in the loop.