[dpdk-dev] [RFC v2 00/17] mempool: add bucket mempool driver

[Andrew Rybchenko]

The patch series starts from generic enhancements suggested by Olivier.
Basically it adds driver callbacks to calculate required memory size and
to populate objects using provided memory area. It allows to remove
so-called capability flags used before to tell generic code how to
allocate and slice allocated memory into mempool objects.
Clean up which removes get_capabilities and register_memory_area is
not strictly required, but I think right thing to do.
Existing mempool drivers are updated.

I've kept rte_mempool_populate_iova_tab() intact since it seems to
be not directly related XMEM API functions.

The patch series adds bucket mempool driver which allows to allocate
(both physically and virtually) contiguous blocks of objects and adds
mempool API to do it. It is still capable to provide separate objects,
but it is definitely more heavy-weight than ring/stack drivers.
The driver will be used by the future Solarflare driver enhancements
which allow to utilize physical contiguous blocks in the NIC
hardware/firmware.

The target usecase is dequeue in blocks and enqueue separate objects
back (which are collected in buckets to be dequeued). So, the memory
pool with bucket driver is created by an application and provided to
networking PMD receive queue. The choice of bucket driver is done using
rte_eth_dev_pool_ops_supported(). A PMD that relies upon contiguous
block allocation should report the bucket driver as the only supported
and preferred one.

Introduction of the contiguous block dequeue operation is proven by
performance measurements using autotest with minor enhancements:
 - in the original test bulks are powers of two, which is unacceptable
   for us, so they are changed to multiple of contig_block_size;
 - the test code is duplicated to support plain dequeue and
   dequeue_contig_blocks;
 - all the extra test variations (with/without cache etc) are eliminated;
 - a fake read from the dequeued buffer is added (in both cases) to
   simulate mbufs access.

start performance test for bucket (without cache)
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=   1 n_keep=  30 Srate_persec=   111935488
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=   1 n_keep=  60 Srate_persec=   115290931
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=  15 n_keep=  30 Srate_persec=   353055539
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=  15 n_keep=  60 Srate_persec=   353330790
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=   1 n_keep=  30 Srate_persec=   224657407
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=   1 n_keep=  60 Srate_persec=   230411468
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=  15 n_keep=  30 Srate_persec=   706700902
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=  15 n_keep=  60 Srate_persec=   703673139
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=   1 n_keep=  30 Srate_persec=   425236887
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=   1 n_keep=  60 Srate_persec=   437295512
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=  15 n_keep=  30 Srate_persec=  1343409356
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=  15 n_keep=  60 Srate_persec=  1336567397
start performance test for bucket (without cache + contiguous dequeue)
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=   1 n_keep=  30 Crate_persec=   122945536
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=   1 n_keep=  60 Crate_persec=   126458265
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=  15 n_keep=  30 Crate_persec=   374262988
mempool_autotest cache=   0 cores= 1 n_get_bulk=  15 n_put_bulk=  15 n_keep=  60 Crate_persec=   377316966
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=   1 n_keep=  30 Crate_persec=   244842496
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=   1 n_keep=  60 Crate_persec=   251618917
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=  15 n_keep=  30 Crate_persec=   751226060
mempool_autotest cache=   0 cores= 2 n_get_bulk=  15 n_put_bulk=  15 n_keep=  60 Crate_persec=   756233010
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=   1 n_keep=  30 Crate_persec=   462068120
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=   1 n_keep=  60 Crate_persec=   476997221
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=  15 n_keep=  30 Crate_persec=  1432171313
mempool_autotest cache=   0 cores= 4 n_get_bulk=  15 n_put_bulk=  15 n_keep=  60 Crate_persec=  1438829771

The number of objects in the contiguous block is a function of bucket
memory size (.config option) and total element size. In the future
additional API with possibility to pass parameters on mempool allocation
may be added.

It breaks ABI since changes rte_mempool_ops. Also it removes
rte_mempool_ops_register_memory_area() and
rte_mempool_ops_get_capabilities() since corresponding callbacks are
removed.

The target DPDK release is 18.05.

v2:
  - add driver ops to calculate required memory size and populate
    mempool objects, remove extra flags which were required before
    to control it
  - transition of octeontx and dpaa drivers to the new callbacks
  - change info API to get information from driver required to
    API user to know contiguous block size
  - remove get_capabilities (not required any more and may be
    substituted with more in info get API)
  - remove register_memory_area since it is substituted with
    populate callback which can do more
  - use SPDX tags
  - avoid all objects affinity to single lcore
  - fix bucket get_count
  - deprecate XMEM API
  - avoid introduction of a new function to flush cache
  - fix NO_CACHE_ALIGN case in bucket mempool

Andrew Rybchenko (10):
  mempool: fix phys contig check if populate default skipped
  mempool: add op to calculate memory size to be allocated
  mempool/octeontx: add callback to calculate memory size
  mempool: add op to populate objects using provided memory
  mempool/octeontx: implement callback to populate objects
  mempool: remove callback to get capabilities
  mempool: deprecate xmem functions
  mempool/octeontx: prepare to remove register memory area op
  mempool/dpaa: convert to use populate driver op
  mempool: remove callback to register memory area

Artem V. Andreev (7):
  mempool: ensure the mempool is initialized before populating
  mempool/bucket: implement bucket mempool manager
  mempool: support flushing the default cache of the mempool
  mempool: implement abstract mempool info API
  mempool: support block dequeue operation
  mempool/bucket: implement block dequeue operation
  mempool/bucket: do not allow one lcore to grab all buckets

 MAINTAINERS                                        |   9 +
 config/common_base                                 |   2 +
 drivers/mempool/Makefile                           |   1 +
 drivers/mempool/bucket/Makefile                    |  27 +
 drivers/mempool/bucket/rte_mempool_bucket.c        | 626 +++++++++++++++++++++
 .../mempool/bucket/rte_mempool_bucket_version.map  |   4 +
 drivers/mempool/dpaa/dpaa_mempool.c                |  13 +-
 drivers/mempool/octeontx/rte_mempool_octeontx.c    |  63 ++-
 lib/librte_mempool/rte_mempool.c                   | 192 ++++---
 lib/librte_mempool/rte_mempool.h                   | 366 +++++++++---
 lib/librte_mempool/rte_mempool_ops.c               |  48 +-
 lib/librte_mempool/rte_mempool_version.map         |  11 +-
 mk/rte.app.mk                                      |   1 +
 13 files changed, 1184 insertions(+), 179 deletions(-)
 create mode 100644 drivers/mempool/bucket/Makefile
 create mode 100644 drivers/mempool/bucket/rte_mempool_bucket.c
 create mode 100644 drivers/mempool/bucket/rte_mempool_bucket_version.map

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2.7.4