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From: Waiman Long <longman@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>, Will Deacon <will.deacon@arm.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Borislav Petkov <bp@alien8.de>, "H. Peter Anvin" <hpa@zytor.com>,
	linux-kernel@vger.kernel.org, x86@kernel.org,
	Davidlohr Bueso <dave@stgolabs.net>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Tim Chen <tim.c.chen@linux.intel.com>,
	huang ying <huang.ying.caritas@gmail.com>
Subject: Re: [PATCH v8 13/19] locking/rwsem: Make rwsem->owner an atomic_long_t
Date: Tue, 4 Jun 2019 11:44:46 -0400	[thread overview]
Message-ID: <0d4d11c4-80e8-f75f-fae8-b653481db260@redhat.com> (raw)
In-Reply-To: <20190604085238.GF3402@hirez.programming.kicks-ass.net>

On 6/4/19 4:52 AM, Peter Zijlstra wrote:
> On Mon, May 20, 2019 at 04:59:12PM -0400, Waiman Long wrote:
>> +static inline struct task_struct *rwsem_read_owner(struct rw_semaphore *sem)
>> +{
>> +	return (struct task_struct *)(atomic_long_read(&sem->owner) &
>> +					~RWSEM_OWNER_FLAGS_MASK);
>> +}
>> +
>> +/*
>> + * Return the real task structure pointer of the owner and the embedded
>> + * flags in the owner. pflags must be non-NULL.
>> + */
>> +static inline struct task_struct *
>> +rwsem_read_owner_flags(struct rw_semaphore *sem, long *pflags)
>> +{
>> +	long owner = atomic_long_read(&sem->owner);
>> +
>> +	*pflags = owner & RWSEM_OWNER_FLAGS_MASK;
>> +	return (struct task_struct *)(owner & ~RWSEM_OWNER_FLAGS_MASK);
>> +}
> I got confused by the 'read' part in those nanes, I initially thought
> they paired with rwsem_set_reader_owned().

Sorry for the confusion. I initially use "get", but I am afraid that it
may get confused with "get/put" for reference counting. So I used read
instead.


> So I've done 's/rwsem_read_owner/rwsem_owner/g on it.

I am fine with getting rid of the "read" from the function names.

Cheers,
Longman


  reply	other threads:[~2019-06-04 15:44 UTC|newest]

Thread overview: 83+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-20 20:58 [PATCH v8 00/19] locking/rwsem: Rwsem rearchitecture part 2 Waiman Long
2019-05-20 20:59 ` [PATCH v8 01/19] locking/rwsem: Make owner available even if !CONFIG_RWSEM_SPIN_ON_OWNER Waiman Long
2019-06-17 14:23   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 02/19] locking/rwsem: Remove rwsem_wake() wakeup optimization Waiman Long
2019-06-17 14:24   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 03/19] locking/rwsem: Implement a new locking scheme Waiman Long
2019-06-17 14:24   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 04/19] locking/rwsem: Merge rwsem.h and rwsem-xadd.c into rwsem.c Waiman Long
2019-06-17 14:25   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 05/19] locking/rwsem: Code cleanup after files merging Waiman Long
2019-06-17 14:26   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 06/19] locking/rwsem: Make rwsem_spin_on_owner() return owner state Waiman Long
2019-06-17 14:27   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 07/19] locking/rwsem: Implement lock handoff to prevent lock starvation Waiman Long
2019-06-04  3:03   ` Yuyang Du
2019-06-04  3:26     ` Yuyang Du
2019-06-04  9:12       ` Boqun Feng
2019-06-04 16:00         ` Waiman Long
2019-06-05  7:48           ` Yuyang Du
2019-06-04 13:21       ` Waiman Long
2019-06-17 14:27   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 08/19] locking/rwsem: Always release wait_lock before waking up tasks Waiman Long
2019-06-17 14:28   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 09/19] locking/rwsem: More optimal RT task handling of null owner Waiman Long
2019-06-17 14:29   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 10/19] locking/rwsem: Wake up almost all readers in wait queue Waiman Long
2019-06-17 14:29   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 11/19] locking/rwsem: Clarify usage of owner's nonspinaable bit Waiman Long
2019-06-17 14:30   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 12/19] locking/rwsem: Enable readers spinning on writer Waiman Long
2019-06-17 14:31   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 13/19] locking/rwsem: Make rwsem->owner an atomic_long_t Waiman Long
2019-06-04  8:52   ` Peter Zijlstra
2019-06-04 15:44     ` Waiman Long [this message]
2019-06-17 14:32   ` [tip:locking/core] " tip-bot for Waiman Long
2019-07-19 18:45   ` [PATCH v8 13/19] " Luis Henriques
2019-07-19 19:32     ` Waiman Long
2019-07-19 19:45       ` Luis Henriques
2019-07-19 20:14         ` Waiman Long
2019-07-19 19:51       ` Linus Torvalds
2019-07-20  8:41         ` Luis Henriques
2019-07-20  9:32           ` Luis Henriques
2019-07-20  9:45             ` Luis Henriques
2019-07-20 11:10           ` Peter Zijlstra
2019-07-20 15:04           ` Waiman Long
2019-07-21 20:49             ` Luis Henriques
2019-07-23  2:57               ` Waiman Long
2019-07-25 15:59             ` [tip:locking/core] locking/rwsem: Don't call owner_on_cpu() on read-owner tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 14/19] locking/rwsem: Enable time-based spinning on reader-owned rwsem Waiman Long
2019-06-04  9:03   ` Peter Zijlstra
2019-06-04 16:54     ` Waiman Long
2019-06-17 14:32   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 15/19] locking/rwsem: Adaptive disabling of reader optimistic spinning Waiman Long
2019-06-04  9:10   ` Peter Zijlstra
2019-06-04 17:28     ` Waiman Long
2019-06-04  9:14   ` Peter Zijlstra
2019-06-04 17:29     ` Waiman Long
2019-06-04  9:20   ` Peter Zijlstra
2019-06-04 17:30     ` Waiman Long
2019-06-04 17:38       ` Peter Zijlstra
2019-06-04 18:04         ` Waiman Long
2019-06-04 18:14           ` Peter Zijlstra
2019-06-04 18:21             ` Waiman Long
2019-06-05 18:13               ` Waiman Long
2019-06-05 20:19                 ` Peter Zijlstra
2019-06-05 20:52                   ` Linus Torvalds
2019-06-06  8:03                     ` Peter Zijlstra
2019-06-06  8:11                       ` Peter Zijlstra
2019-06-04 10:58   ` Peter Zijlstra
2019-06-17 14:33   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 16/19] locking/rwsem: Guard against making count negative Waiman Long
2019-06-11 13:11   ` Peter Zijlstra
2019-06-11 13:27     ` Peter Zijlstra
2019-06-11 13:13   ` Peter Zijlstra
2019-06-17 14:34   ` [tip:locking/core] " tip-bot for Waiman Long
2019-05-20 20:59 ` [PATCH v8 17/19] locking/rwsem: Merge owner into count on x86-64 Waiman Long
2019-06-04  9:45   ` Peter Zijlstra
2019-06-04 15:47     ` Waiman Long
2019-06-04 17:02       ` Peter Zijlstra
2019-06-04 17:06         ` Waiman Long
2019-06-04 17:18           ` Peter Zijlstra
2019-05-20 20:59 ` [PATCH v8 18/19] locking/rwsem: Remove redundant computation of writer lock word Waiman Long
2019-05-20 20:59 ` [PATCH v8 19/19] locking/rwsem: Disable preemption in down_read*() if owner in count Waiman Long

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