These variants of ck_ring_enqueue_* return the snapshot of queue
length with respect to the linearization point. This can be used to
extract ring size without incurring additional cacheline invalidation
overhead from the writer.
I changed the release state to use an enum instead of an unsigned int with #defines in order to make debugging easier. I also removed unnecessary atomic operations in the initializer function, and made some formatting fixes.
I added an extra argument to the CK_COHORT_INIT macro to allow users to specify custom pass limits
when using it. I also added a reference to the paper on which the cohort implementation was based.
The constants and macros in ck_cohort.h didn't conform to CK naming conventions. Additionally, I was able to remove a lot of unnecessary atomic operations and memory fences, which reduced latency by 10-20% and increased throughput using ticket locks by nearly an order of magnitude.
John Wittrock has contributed a phase-fair reader-writer
lock implementation. These locks allow phase fairness
guarantees between readers and writers. This work includes
additional changes and clean-up.
Follow-up work is expected.
Thanks to John Wittrock for patches and Professor Gabriel
Parmer (http://www.seas.gwu.edu/~gparmer/) for advising.
Upon popular request, added a variant of the ticket spinlock
with trylock support. This is pending additional verification
on other architectures besides x86*. It is still unclear whether
this implementation will be the default as it is has slower
fast path.
Add trylock support to the ck_spinlock validation tests.
It currently only tests ck_spinlock_ticket_t trylock
functionality if available.
This primarily involved changing the configure script and adding
several utility functions to regressions/common.h for unit testing.
Signed-off-by: Samy Al Bahra <sbahra@appnexus.com>
Samy Al Bahra
Samy Al Bahra
Brendon Scheinman
David Joseph