For some users, the rte ring's "non-preemptive" constraint is not acceptable; for example, if the application uses a mixture of pinned high-priority threads and multiplexed low-priority threads that share a mempool.
This patchset introduces a non-blocking stack mempool handler. Note that the non-blocking algorithm relies on a 128-bit compare-and-swap, so it is limited to x86_64 machines. In mempool_perf_autotest the lock-based stack outperforms the non-blocking handler*, however: - For applications with preemptible pthreads, a lock-based stack's worst-case performance (i.e. one thread being preempted while holding the spinlock) is much worse than the non-blocking stack's. - Using per-thread mempool caches will largely mitigate the performance difference. *Test setup: x86_64 build with default config, dual-socket Xeon E5-2699 v4, running on isolcpus cores with a tickless scheduler. The lock-based stack's rate_persec was 1x-3.5x the non-blocking stack's. v2: - Merge separate docs commit into patch #2 - Fixed two space-after-typecast issues - Fix alphabetical sorting for build files - Remove unnecessary include path from nb_stack/Makefile - Add a comment to nb_lifo_len() justifying its approximate behavior - Fix comparison with NULL - Remove unnecessary void * cast - Fix meson builds and limit them to x86_64 - Fix missing library error for non-x86_64 builds Gage Eads (2): eal: add 128-bit cmpset (x86-64 only) mempool/nb_stack: add non-blocking stack mempool MAINTAINERS | 4 + config/common_base | 1 + doc/guides/prog_guide/env_abstraction_layer.rst | 5 + drivers/mempool/Makefile | 3 + drivers/mempool/meson.build | 5 + drivers/mempool/nb_stack/Makefile | 23 ++++ drivers/mempool/nb_stack/meson.build | 4 + drivers/mempool/nb_stack/nb_lifo.h | 147 +++++++++++++++++++++ drivers/mempool/nb_stack/rte_mempool_nb_stack.c | 125 ++++++++++++++++++ .../nb_stack/rte_mempool_nb_stack_version.map | 4 + .../common/include/arch/x86/rte_atomic_64.h | 22 +++ mk/rte.app.mk | 7 +- 12 files changed, 348 insertions(+), 2 deletions(-) create mode 100644 drivers/mempool/nb_stack/Makefile create mode 100644 drivers/mempool/nb_stack/meson.build create mode 100644 drivers/mempool/nb_stack/nb_lifo.h create mode 100644 drivers/mempool/nb_stack/rte_mempool_nb_stack.c create mode 100644 drivers/mempool/nb_stack/rte_mempool_nb_stack_version.map -- 2.13.6
