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Date:   Sun, 30 Jul 2023 20:00:33 -0700
From:   Boqun Feng <boqun.feng@gmail.com>
To:     Benno Lossin <benno.lossin@proton.me>
Cc:     Miguel Ojeda <ojeda@kernel.org>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Gary Guo <gary@garyguo.net>,
        =?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
        Alice Ryhl <aliceryhl@google.com>,
        Andreas Hindborg <nmi@metaspace.dk>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        Asahi Lina <lina@asahilina.net>
Subject: Re: [PATCH v3 08/13] rust: init: Add functions to create array
 initializers
Message-ID: <ZMcj0TswxyCu5hpd@boqun-archlinux>
References: <20230729090838.225225-1-benno.lossin@proton.me>
 <20230729090838.225225-9-benno.lossin@proton.me>
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On Sat, Jul 29, 2023 at 09:10:02AM +0000, Benno Lossin wrote:
[...]
> +/// Initializes an array by initializing each element via the provided initializer.
> +///
> +/// # Examples
> +///
> +/// ```rust
> +/// use kernel::{sync::{Arc, Mutex}, init::pin_init_array_from_fn, new_mutex};
> +/// let array: Arc<[Mutex<usize>; 1_000_000_000]>=

This is nice, but (if I got my math correct) it requires ~30G memory on
a 64bit machine, and when this example got generated as a kunit test,
my poor VM took forever to finish it ;-) ;-) ;-) Maybe descrease it to,
say, 1000?

Regards,
Boqun

> +///     Arc::pin_init(pin_init_array_from_fn(|i| new_mutex!(i))).unwrap();
> +/// assert_eq!(array.len(), 1_000_000_000);
> +/// ```
[...]