Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1199049

[PATCH v4 0/8] Add generic support for relaxed atomics

Show all headers | View raw

Hello,

Here is version four of the patches previously posted here:

  v1: https://lwn.net/Articles/650862/
  v2: https://lwn.net/Articles/651293/
  v3: https://lwn.net/Articles/652369/

The series adds support for a family of relaxed atomics to the kernel.
More specifically:

  - acquire/release/relaxed flavours of xchg, cmpxchg and {add,sub}_return
  - atomic_read_acquire
  - atomic_set_release

This came out of a separate patch series porting the (barrier-heavy)
qrwlock code to arm64. Rather than have arch-specific hooks littered
around the place, it makes more sense to define a core set of relaxed
atomics that can be used regardless of architecture.

The only change since v3 is an extension to the comment in
linux/atomic.h, as suggested by Peter.

Build tested on ARM, arm64, PowerPC and x86.

All feedback welcome,

Will

--->8

Will Deacon (8):
  atomics: add acquire/release/relaxed variants of some atomic
    operations
  asm-generic: rework atomic-long.h to avoid bulk code duplication
  asm-generic: add relaxed/acquire/release variants for atomic_long_t
  lockref: remove homebrew cmpxchg64_relaxed macro definition
  locking/qrwlock: implement queue_write_unlock using smp_store_release
  locking/qrwlock: make use of acquire/release/relaxed atomics
  include/llist: use linux/atomic.h instead of asm/cmpxchg.h
  ARM: atomics: define our SMP atomics in terms of _relaxed operations

 arch/arm/include/asm/atomic.h     |  37 ++---
 arch/arm/include/asm/cmpxchg.h    |  47 +-----
 arch/x86/include/asm/qrwlock.h    |  10 --
 include/asm-generic/atomic-long.h | 263 +++++++++++-------------------
 include/asm-generic/qrwlock.h     |  22 +--
 include/linux/atomic.h            | 328 ++++++++++++++++++++++++++++++++++++++
 include/linux/llist.h             |   2 +-
 kernel/locking/qrwlock.c          |  23 ++-
 lib/lockref.c                     |   8 -
 9 files changed, 468 insertions(+), 272 deletions(-)

-- 
2.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

[PATCH v4 0/8] Add generic support for relaxed atomics Will Deacon <will.deacon@arm.com> - 2015-08-03 19:10 +0200
  [PATCH v4 6/8] locking/qrwlock: make use of acquire/release/relaxed atomics Will Deacon <will.deacon@arm.com> - 2015-08-03 19:10 +0200
    Re: [PATCH v4 6/8] locking/qrwlock: make use of acquire/release/relaxed  atomics Waiman Long <waiman.long@hp.com> - 2015-08-03 22:50 +0200
      Re: [PATCH v4 6/8] locking/qrwlock: make use of  acquire/release/relaxed atomics Will Deacon <will.deacon@arm.com> - 2015-08-04 13:30 +0200
  [PATCH v4 5/8] locking/qrwlock: implement queue_write_unlock using smp_store_release Will Deacon <will.deacon@arm.com> - 2015-08-03 19:10 +0200
    Re: [PATCH v4 5/8] locking/qrwlock: implement queue_write_unlock  using smp_store_release Waiman Long <waiman.long@hp.com> - 2015-08-03 22:50 +0200
  [PATCH v4 7/8] include/llist: use linux/atomic.h instead of asm/cmpxchg.h Will Deacon <will.deacon@arm.com> - 2015-08-03 19:20 +0200
  [PATCH v4 8/8] ARM: atomics: define our SMP atomics in terms of _relaxed operations Will Deacon <will.deacon@arm.com> - 2015-08-03 19:20 +0200
  [PATCH v4 2/8] asm-generic: rework atomic-long.h to avoid bulk code duplication Will Deacon <will.deacon@arm.com> - 2015-08-03 19:20 +0200
  [PATCH v4 1/8] atomics: add acquire/release/relaxed variants of some atomic operations Will Deacon <will.deacon@arm.com> - 2015-08-03 19:20 +0200
    Re: [PATCH v4 1/8] atomics: add acquire/release/relaxed variants of  some atomic operations Peter Zijlstra <peterz@infradead.org> - 2015-08-03 19:30 +0200
      Re: [PATCH v4 1/8] atomics: add acquire/release/relaxed variants of  some atomic operations Will Deacon <will.deacon@arm.com> - 2015-08-03 20:30 +0200
  [PATCH v4 3/8] asm-generic: add relaxed/acquire/release variants for atomic_long_t Will Deacon <will.deacon@arm.com> - 2015-08-03 19:20 +0200

csiph-web