From: David Laight <David.Laight@ACULAB.COM>
To: 'Haris Okanovic' <harisokn@amazon.com>,
"ankur.a.arora@oracle.com" <ankur.a.arora@oracle.com>,
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Subject: RE: [PATCH 2/5] arm64: add __READ_ONCE_EX()
Date: Sat, 9 Nov 2024 09:49:03 +0000 [thread overview]
Message-ID: <c2bee816a4a44d55951ca839fea0a6dd@AcuMS.aculab.com> (raw)
In-Reply-To: <20241105183041.1531976-3-harisokn@amazon.com>
From: Haris Okanovic
> Sent: 05 November 2024 18:31
>
> Perform an exclusive load, which atomically loads a word and arms the
> exclusive monitor to enable wfet()/wfe() accelerated polling.
>
...
> + atomic ? (typeof(*__x))__u.__val : (*(volatile typeof(__x))__x);\
That doesn't do what you want it to do.
(It is wrong in READ_ONCE() as well.)
?: is treated like an arithmetic operator and the result will get
promoted to 'int'.
Moving the first cast outside the ?: probably works:
(typeof(*__x))(atomic ? __u.__val : (*(volatile typeof(__x))__x));
David
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next prev parent reply other threads:[~2024-11-09 9:49 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-25 23:24 [PATCH v8 00/11] Enable haltpoll on arm64 Ankur Arora
2024-09-25 23:24 ` [PATCH v8 01/11] cpuidle/poll_state: poll via smp_cond_load_relaxed() Ankur Arora
2024-10-15 12:04 ` Catalin Marinas
2024-10-15 16:42 ` Christoph Lameter (Ampere)
2024-10-15 16:50 ` Catalin Marinas
2024-10-15 17:17 ` Christoph Lameter (Ampere)
2024-10-15 17:40 ` Catalin Marinas
2024-10-15 21:53 ` Ankur Arora
2024-10-15 22:28 ` Christoph Lameter (Ampere)
2024-10-16 7:06 ` Ankur Arora
2024-10-17 16:54 ` Christoph Lameter (Ampere)
2024-10-17 18:36 ` Ankur Arora
2024-10-15 22:40 ` Christoph Lameter (Ampere)
2024-10-16 9:54 ` Catalin Marinas
2024-10-17 16:56 ` Christoph Lameter (Ampere)
2024-10-17 18:15 ` Catalin Marinas
2024-10-17 19:34 ` Ankur Arora
2024-10-15 21:32 ` Ankur Arora
2024-10-16 6:20 ` maobibo
2024-10-16 10:06 ` Catalin Marinas
2024-10-16 15:13 ` Okanovic, Haris
2024-10-16 17:04 ` Ankur Arora
2024-10-16 18:04 ` Okanovic, Haris
2024-10-17 14:01 ` Catalin Marinas
2024-10-17 22:47 ` Ankur Arora
2024-10-18 11:05 ` Catalin Marinas
2024-10-18 19:00 ` Ankur Arora
2024-10-21 12:02 ` Catalin Marinas
2024-09-25 23:24 ` [PATCH v8 02/11] cpuidle: rename ARCH_HAS_CPU_RELAX to ARCH_HAS_OPTIMIZED_POLL Ankur Arora
2024-09-25 23:24 ` [PATCH v8 03/11] Kconfig: move ARCH_HAS_OPTIMIZED_POLL to arch/Kconfig Ankur Arora
2024-09-25 23:24 ` [PATCH v8 04/11] cpuidle-haltpoll: define arch_haltpoll_want() Ankur Arora
2024-09-25 23:24 ` [PATCH v8 05/11] governors/haltpoll: drop kvm_para_available() check Ankur Arora
2024-09-25 23:24 ` [PATCH v8 06/11] cpuidle-haltpoll: condition on ARCH_CPUIDLE_HALTPOLL Ankur Arora
2024-09-25 23:24 ` [PATCH v8 07/11] arm64: define TIF_POLLING_NRFLAG Ankur Arora
2024-09-25 23:24 ` [PATCH v8 08/11] arm64: idle: export arch_cpu_idle Ankur Arora
2024-09-25 23:24 ` [PATCH v8 09/11] arm64: select ARCH_HAS_OPTIMIZED_POLL Ankur Arora
2024-09-25 23:24 ` [PATCH v8 10/11] cpuidle/poll_state: limit POLL_IDLE_RELAX_COUNT on arm64 Ankur Arora
2024-09-25 23:24 ` [PATCH v8 11/11] arm64: support cpuidle-haltpoll Ankur Arora
2024-10-02 22:42 ` Okanovic, Haris
2024-10-03 3:29 ` Ankur Arora
2024-10-16 15:13 ` Okanovic, Haris
2024-10-09 2:37 ` [PATCH v8 00/11] Enable haltpoll on arm64 zhenglifeng (A)
2024-10-15 1:53 ` Ankur Arora
2024-10-14 22:54 ` Christoph Lameter (Ampere)
2024-10-15 12:36 ` Marc Zyngier
2024-10-16 21:55 ` Ankur Arora
2024-10-17 8:19 ` Marc Zyngier
2024-10-17 18:35 ` Ankur Arora
2024-10-22 22:01 ` Ankur Arora
2024-11-05 18:30 ` Haris Okanovic
2024-11-05 18:30 ` [PATCH 1/5] asm-generic: add smp_vcond_load_relaxed() Haris Okanovic
2024-11-05 19:36 ` Christoph Lameter (Ampere)
2024-11-06 17:06 ` Okanovic, Haris
2024-11-06 11:08 ` Catalin Marinas
2024-11-06 18:13 ` Okanovic, Haris
2024-11-06 19:55 ` Catalin Marinas
2024-11-06 20:31 ` Okanovic, Haris
2024-11-06 11:39 ` Will Deacon
2024-11-06 17:18 ` Okanovic, Haris
2024-11-05 18:30 ` [PATCH 2/5] arm64: add __READ_ONCE_EX() Haris Okanovic
2024-11-05 19:39 ` Christoph Lameter (Ampere)
2024-11-06 17:37 ` Okanovic, Haris
2024-11-06 11:43 ` Will Deacon
2024-11-06 17:09 ` Okanovic, Haris
2024-11-09 9:49 ` David Laight [this message]
2024-11-05 18:30 ` [PATCH 3/5] arm64: refactor delay() to enable polling for value Haris Okanovic
2024-11-05 19:42 ` Christoph Lameter (Ampere)
2024-11-06 17:42 ` Okanovic, Haris
2024-11-06 9:18 ` Catalin Marinas
2024-11-06 17:38 ` Okanovic, Haris
2024-11-05 18:30 ` [PATCH 4/5] arm64: add smp_vcond_load_relaxed() Haris Okanovic
2024-11-05 18:30 ` [PATCH 5/5] cpuidle: implement poll_idle() using smp_vcond_load_relaxed() Haris Okanovic
2024-11-05 19:45 ` Christoph Lameter (Ampere)
2024-11-05 18:49 ` [PATCH v8 00/11] Enable haltpoll on arm64 Ankur Arora
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