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Message-ID: <e51e9fb1-ad5c-5cf8-fa04-4e3a10023739@sandeen.net>
Date:   Tue, 4 Apr 2023 09:19:06 -0500
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To:     Ryosuke Yasuoka <ryasuoka@redhat.com>, djwong@kernel.org
Cc:     linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230404084701.2791683-1-ryasuoka@redhat.com>
From:   Eric Sandeen <sandeen@sandeen.net>
Subject: Re: [PATCH] xfs: Use for_each_perag() to iterate all available AGs
In-Reply-To: <20230404084701.2791683-1-ryasuoka@redhat.com>
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On 4/4/23 3:47 AM, Ryosuke Yasuoka wrote:
> for_each_perag_wrap() doesn't expect 0 as 2nd arg.
> To iterate all the available AGs, just use for_each_perag() instead.

Can you explain what goes wrong if it is zero? Is there a test for this?

If it's a general problem, what if the other 2 callers pass in the variable
start_agno with a value of 0?

(I may well be missing something obvious as those macros are a bit dense)

Thanks,
-Eric
 
> Signed-off-by: Ryosuke Yasuoka <ryasuoka@redhat.com>
> ---
>  fs/xfs/xfs_filestream.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c
> index 22c13933c8f8..48f43c340c58 100644
> --- a/fs/xfs/xfs_filestream.c
> +++ b/fs/xfs/xfs_filestream.c
> @@ -151,7 +151,7 @@ xfs_filestream_pick_ag(
>  		 * grab.
>  		 */
>  		if (!max_pag) {
> -			for_each_perag_wrap(args->mp, 0, start_agno, args->pag)
> +			for_each_perag(args->mp, start_agno, args->pag)
>  				break;
>  			atomic_inc(&args->pag->pagf_fstrms);
>  			*longest = 0;