[v3,0/2] rwlock: allow recursive read locking when already locked in write mode

Message

Roger Pau Monné Feb. 24, 2020, 8:43 a.m. UTC

Hello,

The following series implement support for read-locking a lock already
taken in write mode by the same CPU. Patch #1 add an atomic_and
operation to be used by patch #2 which implements the mentioned
behavior.

The series has been build tested on Arm by gitlab:

https://gitlab.com/xen-project/people/royger/xen/pipelines/120144901

Thanks, Roger.

Roger Pau Monne (2):
  atomic: add atomic_and operations
  rwlock: allow recursive read locking when already locked in write mode

 xen/common/rwlock.c                |  4 +--
 xen/include/asm-arm/arm32/atomic.h | 17 ++++++++++
 xen/include/asm-arm/arm64/atomic.h | 14 ++++++++
 xen/include/asm-x86/atomic.h       |  8 +++++
 xen/include/xen/rwlock.h           | 52 ++++++++++++++++++------------
 5 files changed, 73 insertions(+), 22 deletions(-)