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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Peter Zijlstra' <peterz@infradead.org>,
        Wedson Almeida Filho <wedsonaf@gmail.com>
CC:     Greg KH <gregkh@linuxfoundation.org>,
        "rust-for-linux@vger.kernel.org" <rust-for-linux@vger.kernel.org>,
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        Wedson Almeida Filho <walmeida@microsoft.com>,
        Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Waiman Long <longman@redhat.com>
Subject: RE: [PATCH v2 03/13] rust: lock: introduce `Mutex`
Thread-Topic: [PATCH v2 03/13] rust: lock: introduce `Mutex`
Thread-Index: AQHZaAAyCAs/X7+57kyon/cEM0LTmK8d9EKQ
Date:   Thu, 6 Apr 2023 08:38:24 +0000
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From: Peter Zijlstra
> Sent: 05 April 2023 21:50
> 
> On Wed, Apr 05, 2023 at 05:40:39PM -0300, Wedson Almeida Filho wrote:
...
> > So the situation is improved in that we don't need to manually write (and
> > commit) the helpers. It may improve further in the future if we get better
> > integration of the languages.
> 
> But yeah, feel free to convert macros to inline functions where the
> difference is moot. There is indeed no real reason for mutex_lock() to
> not be an inline function in that case.

mutex_lock() is probably ok.
But there are cases where gcc generates much better code
for #defines than for inline functions.
Almost certainly because the front end gets to optimise
#defines, but inlines are done much later on.

	David

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