mbox series

[00/12] Introduce cmpxchg128() -- aka. the demise of cmpxchg_double()

Message ID 20230531130833.635651916@infradead.org
Headers show
Series Introduce cmpxchg128() -- aka. the demise of cmpxchg_double() | expand

Message

Peter Zijlstra May 31, 2023, 1:08 p.m. UTC 
Hi!

After much breaking of things, find here the improved version.

Since v3:

 - unbreak everything that does *NOT* have cmpxchg128()

   Notably this_cpu_cmpxchg_double() is used unconditionally by SLUB
   which means that this_cpu_try_cmpxchg128() needs to be unconditionally
   available on all 64bit architectures.

 - fixed up x86/x86_64 cmpxchg{8,16}b emulation for this_cpu_cmpxchg{64,128}()

 - introduce {raw,this}_cpu_try_cmpxchg*()

 - add fallback for !__SIZEOF_INT128__ 64bit architectures

   Sadly there are supported 64bit architecture/compiler combinations that do
   not have __SIZEOF_INT128__, specifically it was found that HPPA64 only added
   this with GCC-11.

   this is yuck, and ideally we'd simply raise compiler requirements, but this
   'works'.

My plan is to re-add this to tip/locking/core and thus -next later this week.

Also available at:

  git://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git locking/core

---
 Documentation/core-api/this_cpu_ops.rst     |   2 -
 arch/arm64/include/asm/atomic_ll_sc.h       |  56 +++---
 arch/arm64/include/asm/atomic_lse.h         |  39 ++---
 arch/arm64/include/asm/cmpxchg.h            |  48 ++----
 arch/arm64/include/asm/percpu.h             |  30 ++--
 arch/s390/include/asm/cmpxchg.h             |  32 +---
 arch/s390/include/asm/cpu_mf.h              |   2 +-
 arch/s390/include/asm/percpu.h              |  34 ++--
 arch/s390/kernel/perf_cpum_sf.c             |  16 +-
 arch/x86/include/asm/cmpxchg.h              |  25 ---
 arch/x86/include/asm/cmpxchg_32.h           |   2 +-
 arch/x86/include/asm/cmpxchg_64.h           |  63 ++++++-
 arch/x86/include/asm/percpu.h               | 102 ++++++-----
 arch/x86/lib/Makefile                       |   3 +-
 arch/x86/lib/cmpxchg16b_emu.S               |  43 +++--
 arch/x86/lib/cmpxchg8b_emu.S                |  67 ++++++--
 drivers/iommu/amd/amd_iommu_types.h         |   9 +-
 drivers/iommu/amd/iommu.c                   |  10 +-
 drivers/iommu/intel/irq_remapping.c         |   8 +-
 include/asm-generic/percpu.h                | 257 ++++++++++++++++++++++------
 include/crypto/b128ops.h                    |  14 +-
 include/linux/atomic/atomic-arch-fallback.h |  95 +++++++++-
 include/linux/atomic/atomic-instrumented.h  |  93 ++++++++--
 include/linux/dmar.h                        | 125 +++++++-------
 include/linux/percpu-defs.h                 |  45 ++---
 include/linux/slub_def.h                    |  12 +-
 include/linux/types.h                       |  12 ++
 include/uapi/linux/types.h                  |   4 +
 lib/crypto/curve25519-hacl64.c              |   2 -
 lib/crypto/poly1305-donna64.c               |   2 -
 mm/slab.h                                   |  53 +++++-
 mm/slub.c                                   | 139 +++++++++------
 scripts/atomic/gen-atomic-fallback.sh       |   4 +-
 scripts/atomic/gen-atomic-instrumented.sh   |  19 +-
 34 files changed, 952 insertions(+), 515 deletions(-)