Re: [PATCH V2 11/19] csky: Atomic operations

On Fri, Jul 06, 2018 at 02:03:23PM +0200, Peter Zijlstra wrote:

quoted

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Test-and-set with MB acting as ACQUIRE, ok.

Em ... Ok, I'll try to use test-and-set function instead of it.

"test-and-set" is just the name of this type of spinlock implementation.

You _could_ use the linux test_and_set bitop, but those are defined on
unsigned long and spinlock_t is generally assumed to be of unsigned int
size.

Go with the ticket locks as per below.

Ok, I'll learn it.

quoted

Ok, I'll try to implement ticket lock in next version patch.

If you need inspiration, look at:

arch/arm/include/asm/spinlock.h

Or look at the current version of that file and ignore the LSE version.

Note that unlock is a store half-word (u16), not having seen your arch
manual yet I don't know if you even have that.

Nice tips, thank you very much.

 Guo Ren