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From: Josef Bacik <josef@toxicpanda.com>
To: Mateusz Guzik <mjguzik@gmail.com>
Cc: brauner@kernel.org, viro@zeniv.linux.org.uk, jack@suse.cz,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] vfs: only read fops once in fops_get/put
Date: Thu, 8 Aug 2024 16:55:08 -0400	[thread overview]
Message-ID: <20240808205508.GC625513@perftesting> (raw)
In-Reply-To: <20240808155429.1080545-1-mjguzik@gmail.com>

On Thu, Aug 08, 2024 at 05:54:28PM +0200, Mateusz Guzik wrote:
> The compiler emits 2 access in fops_get(), put is patched to maintain some
> consistency.
> 
> This makes do_dentry_open() go down from 1177 to 1154 bytes.
> 
> This popped up due to false-sharing where loads from inode->i_fop end up
> bouncing a cacheline on parallel open. While this is going to be fixed,
> the spurious load does not need to be there.
> 
> No functional changes.
> 
> Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>

Reviewed-by: Josef Bacik <josef@toxicpanda.com>

Thanks,

Josef

  reply	other threads:[~2024-08-08 20:55 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-08-08 15:54 [PATCH] vfs: only read fops once in fops_get/put Mateusz Guzik
2024-08-08 20:55 ` Josef Bacik [this message]
2024-08-09  8:30 ` Christian Brauner

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