Date:   Thu, 2 Feb 2023 14:15:00 +0000
From:   Gary Guo <gary@garyguo.net>
To:     Boqun Feng <boqun.feng@gmail.com>
Cc:     rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        Will Deacon <will@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        =?UTF-8?B?QmrDtnJu?= Roy Baron <bjorn3_gh@protonmail.com>,
        Vincenzo Palazzo <vincenzopalazzodev@gmail.com>
Subject: Re: [RFC 1/5] rust: sync: impl Display for {Unique,}Arc
Message-ID: <20230202141500.2b7d348f.gary@garyguo.net>
In-Reply-To: <20230201232244.212908-2-boqun.feng@gmail.com>
References: <20230201232244.212908-1-boqun.feng@gmail.com>
        <20230201232244.212908-2-boqun.feng@gmail.com>
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?1T0uP8oYL81OJRZoGJ1hQoJdcZEr83owFW4401W3VDa57MAO2dMtemX2tmdt?=
 =?us-ascii?Q?o0j6nLHxtB0e2f8BexS7VlNkgwwQ0xFZHYbJmJxOn52SlLS/CSMIAhRplEtl?=
 =?us-ascii?Q?HxtDCh+F4LpAUIkfbEDn3zHSSOrcG++b3JF8ZNriW9J1JiQlrD/zIzWf+k/q?=
 =?us-ascii?Q?Jpq4sY1FMyAkuAKn6FbpZ+pO2C6JPTeiTz6SRa9fYgEB+fLk/EJ2kwbpeSZW?=
 =?us-ascii?Q?EavRXHqtiMJWvdIGiIg7ErqxvzcWVGKwefmsCRILFvBgqgjrsBonMhx8nSoH?=
 =?us-ascii?Q?5EdVnd+fFVtgASR3L55G9RhRXz/WN7Wl6NvWxt7tuEHhgiTHo3a7sE2Vw0QG?=
 =?us-ascii?Q?8Ocpic5kEP6NRQeExczvTgzcBrr2y/3LoNJJelrOlDlxlsO4EJLyXsm6ka/h?=
 =?us-ascii?Q?ci5v4IZozkWQSI83sKIiLdvyljSeekqnMfIRfkgRihSqQoInr3UQWR9HRn2/?=
 =?us-ascii?Q?D0s6GZjvVYYMk6FjudCqYXv+uskVDRwz7wrLHCDMXY/ypr7Ev4jgvZJJEcio?=
 =?us-ascii?Q?ZRsLdjV/8+J4CbslIEEIPaAy6ZoC5S9bPkuW39EZi745PwVEj6MRKVy62mZK?=
 =?us-ascii?Q?ti3oLFdjf55IFTtRkQ9z0SCflDnLiG3sRi5DeXQtBTGj/1/zZc3V8YFTYXbm?=
 =?us-ascii?Q?AFC9mzH0gUa77h+KqIGXa8rQs5CUQ/4+hcP0Eh3ZYYnsmr2/YJ43HeqoYOvk?=
 =?us-ascii?Q?X+3e5KIc0QLD2P5g7L+j8zT6Do5VPPLu/L7UNK5k4cq9xDds6tYR0Sz/tber?=
 =?us-ascii?Q?wCs9jT/92ruK5ArGoSyZEpRCk4EEA0orZF6AGVx8ISg8TriON9iJK0Dg8EQ7?=
 =?us-ascii?Q?eqD+V1Xs8Gd9F0dOauAuqH35QS7oxrKjagGVbnYwsGMiN9UNFag25buP8CWi?=
 =?us-ascii?Q?uGO5MsTNptOoaWEfayxGgvF/ERkAHaMKZgpWpmD39AzZwRgi5/n77G2G4nLU?=
 =?us-ascii?Q?0W4V1k7GX480UDM2VjLNTyLbZsT9wsOKmaRAzn2b5FsnsmZ0YAjyMTfuM42T?=
 =?us-ascii?Q?5l5hxW30Ogz3U/C+8K/2igXMKgi0951mn//Wfcsi5PpmalrNKCJIwRJr33GR?=
 =?us-ascii?Q?oTDhYN7KKu6uAOGMhjhH8aMXLku/ey+pu6voVz6Ws+SPINOOVUpX5G3sLt2O?=
 =?us-ascii?Q?iekWTgW/LSBkcVwfw8UhzRAtGA7D5zKFBzQpnwItbQZpL//HGOQTtGFreOeo?=
 =?us-ascii?Q?Rqs+k2PpY36OArxZlO5o95f1try71zvTKsWCtOTNo/2D+qKdmj37dj/RMB3M?=
 =?us-ascii?Q?fJpISMLS4A+rEo0qGe845oGEKaU0O8OFd99WmO+Pdi2WsXR86nkFwIIcClbR?=
 =?us-ascii?Q?tib+K9Pm/9mKBskzRz+YHOi/bqehbN33G/GO4pKeAzaYUISklFEcz04snmex?=
 =?us-ascii?Q?zLm93YMbompyrxtIXZ+WgKBwCmJr73M+4RLuNegv9nh/LcatkH5julEJu/7t?=
 =?us-ascii?Q?wN6MGNobmi1asDMg6sQGYRVw3pVEytpj6964V978nMI62JVp7qxWCVEfP5g0?=
 =?us-ascii?Q?CykuFY9TrVb5jsAxLSEcW1pJQZkej2mPvC4kosT9qDr3zLWjhG8W+lkEXgtT?=
 =?us-ascii?Q?tUQOFzoGvTfXh5WEZulvA49xRhx7vWWSjKStBOdZ?=
X-OriginatorOrg: garyguo.net
X-MS-Exchange-CrossTenant-Network-Message-Id: c3765c62-6ea4-4626-6623-08db0527dfc4
X-MS-Exchange-CrossTenant-AuthSource: LO2P265MB5183.GBRP265.PROD.OUTLOOK.COM
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Feb 2023 14:15:02.0842
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: bbc898ad-b10f-4e10-8552-d9377b823d45
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: zWEb/5SSXZUZEE4HriBVaQezzJlKYNKnNzLauZ5tyPwBWwOyo4Do6OrRNOyNqQWsOY1zGwGXXYuNGk9ekB3Olg==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CWLP265MB5881
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Wed,  1 Feb 2023 15:22:40 -0800
Boqun Feng <boqun.feng@gmail.com> wrote:

> This allows printing the inner data of `Arc` and its friends if the
> inner data implements `Display`. It's useful for logging and debugging
> purpose.
> 
> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>

Reviewed-by: Gary Guo <gary@garyguo.net>

> ---
>  rust/kernel/sync/arc.rs | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
> index 519a6ec43644..fc680a4a795c 100644
> --- a/rust/kernel/sync/arc.rs
> +++ b/rust/kernel/sync/arc.rs
> @@ -22,6 +22,7 @@ use crate::{
>  };
>  use alloc::boxed::Box;
>  use core::{
> +    fmt,
>      marker::{PhantomData, Unsize},
>      mem::{ManuallyDrop, MaybeUninit},
>      ops::{Deref, DerefMut},
> @@ -522,3 +523,15 @@ impl<T: ?Sized> DerefMut for UniqueArc<T> {
>          unsafe { &mut self.inner.ptr.as_mut().data }
>      }
>  }
> +
> +impl<T: fmt::Display + ?Sized> fmt::Display for UniqueArc<T> {
> +    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> +        fmt::Display::fmt(self.deref(), f)
> +    }
> +}
> +
> +impl<T: fmt::Display + ?Sized> fmt::Display for Arc<T> {
> +    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> +        fmt::Display::fmt(self.deref(), f)
> +    }
> +}