linux-kernel - Re: [PATCH] locking/ww-mutex: use swap()

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <a24c716b-258e-f698-c03e-e81b86b1dcf8@redhat.com>
Date:   Tue, 19 Oct 2021 10:04:27 -0400
From:   Waiman Long <longman@...hat.com>
To:     cgel.zte@...il.com, mingo@...hat.com
Cc:     will@...nel.org, boqun.feng@...il.com,
        linux-kernel@...r.kernel.org,
        Changcheng Deng <deng.changcheng@....com.cn>,
        Zeal Robot <zealci@....com.cn>
Subject: Re: [PATCH] locking/ww-mutex: use swap()

On 10/18/21 11:22 PM, cgel.zte@...il.com wrote:
> From: Changcheng Deng <deng.changcheng@....com.cn>
>
> Use swap() in order to make code cleaner. Issue found by coccinelle.
>
> Reported-by: Zeal Robot <zealci@....com.cn>
> Signed-off-by: Changcheng Deng <deng.changcheng@....com.cn>
> ---
>   kernel/locking/test-ww_mutex.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c
> index 353004155d65..daad819fcd16 100644
> --- a/kernel/locking/test-ww_mutex.c
> +++ b/kernel/locking/test-ww_mutex.c
> @@ -389,7 +389,7 @@ struct stress {
>   static int *get_random_order(int count)
>   {
>   	int *order;
> -	int n, r, tmp;
> +	int n, r;
>   
>   	order = kmalloc_array(count, sizeof(*order), GFP_KERNEL);
>   	if (!order)
> @@ -401,9 +401,7 @@ static int *get_random_order(int count)
>   	for (n = count - 1; n > 1; n--) {
>   		r = get_random_int() % (n + 1);
>   		if (r != n) {
> -			tmp = order[n];
> -			order[n] = order[r];
> -			order[r] = tmp;
> +			swap(order[n], order[r]);
>   		}
>   	}
>   

You can also get rid of the {} as well. I will also suggest clarifying 
in the patch title that you are cleaning up WW mutex selftest instead of 
the WW mutex code itself as that was my initial assumption when I saw 
the subject line.

Cheers,
Longman