çå: [PATCH -next] mmc: core: Use DEFINE_DEBUGFS_ATTRIBUTE instead of DEFINE_SIMPLE_ATTRIBUTE

[Zouwei (Samuel)]

Hi Ulf,

Thanks for your review and reply.

1. DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file() imposes some significant overhead as compared to DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().
  You can refer to the patch of 1a2b3666da58 ("mt76: fix debugfs_simple_attr.cocci warnings")
2. debugfs_create_file_unsafe(...&mmc_clock_fops) is corresponds to DEFINE_DEBUGFS_ATTRIBUTE(mmc_clock_fops...), so I only modified this one.

-----éäåä-----
åää: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx] 
åéæé: 2020å4æ23æ 19:17
æää: Zouwei (Samuel) <zou_wei@xxxxxxxxxx>
æé: linux-mmc@xxxxxxxxxxxxxxx; Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx>
äé: Re: [PATCH -next] mmc: core: Use DEFINE_DEBUGFS_ATTRIBUTE instead of DEFINE_SIMPLE_ATTRIBUTE

On Thu, 23 Apr 2020 at 11:09, Zou Wei <zou_wei@xxxxxxxxxx> wrote:
>
> Fixes coccicheck warning:
>
> drivers/mmc/core/debugfs.c:222:0-23: WARNING: mmc_clock_fops should be 
> defined with DEFINE_DEBUGFS_ATTRIBUTE
>
> Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE for 
> debugfs files
>
> Fixes: 703aae3d09a4b ("mmc: add a file to debugfs for changing host 
> clock at runtime")
> Fixes: a04c50aaa916f ("mmc: core: no need to check return value of 
> debugfs_create functions")
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Zou Wei <zou_wei@xxxxxxxxxx>
> ---
>  drivers/mmc/core/debugfs.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mmc/core/debugfs.c b/drivers/mmc/core/debugfs.c 
> index 09e0c76..9ec84c8 100644
> --- a/drivers/mmc/core/debugfs.c
> +++ b/drivers/mmc/core/debugfs.c
> @@ -219,7 +219,7 @@ static int mmc_clock_opt_set(void *data, u64 val)
>         return 0;
>  }
>
> -DEFINE_SIMPLE_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, 
> mmc_clock_opt_set,
> +DEFINE_DEBUGFS_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, 
> +mmc_clock_opt_set,
>         "%llu\n");
>
>  void mmc_add_host_debugfs(struct mmc_host *host) @@ -232,8 +232,8 @@ 
> void mmc_add_host_debugfs(struct mmc_host *host)
>         debugfs_create_file("ios", S_IRUSR, root, host, &mmc_ios_fops);
>         debugfs_create_x32("caps", S_IRUSR, root, &host->caps);
>         debugfs_create_x32("caps2", S_IRUSR, root, &host->caps2);
> -       debugfs_create_file("clock", S_IRUSR | S_IWUSR, root, host,
> -                           &mmc_clock_fops);
> +       debugfs_create_file_unsafe("clock", S_IRUSR | S_IWUSR, root, host,
> +                                  &mmc_clock_fops);

Apologize for my ignorance, but why convert to the *_unsafe option for this one, but not for the others?

[...]

Kind regards
Uffe