[dpdk-dev] [PATCH v4] build: add meson options of max_memseg_lists and atomic_mbuf_ref_counts

[Kefu Chai <tchaikov@gmail.com>]

RTE_MAX_MEMSEG_LISTS = 128 is not enough for high-memory machines, in our
case, we need to increase it to 8192. so add an option so user can
override it. RTE_MBUF_REFCNT_ATOMIC = 0 is not necessary for applications
like Seastar, where it's safe to assume that the mbuf refcnt is only
updated by a single core only.

---

v4:

fix the coding style issue by reduce the line length to under 75.
this change should silence the warning like:

WARNING:COMMIT_LOG_LONG_LINE: Possible unwrapped commit description (prefer a maximum 75 chars per line)
#81: 
RTE_MAX_MEMSEG_LISTS = 128 is not enough for high-memory machines, in our case,

total: 0 errors, 1 warnings, 35 lines checked

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
---
 config/meson.build  | 5 ++++-
 config/rte_config.h | 2 --
 meson_options.txt   | 4 ++++
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/config/meson.build b/config/meson.build
index 3b5966ec2f..d95dccdbcc 100644
--- a/config/meson.build
+++ b/config/meson.build
@@ -301,7 +301,10 @@ if dpdk_conf.get('RTE_ARCH_64')
 else # for 32-bit we need smaller reserved memory areas
     dpdk_conf.set('RTE_MAX_MEM_MB', 2048)
 endif
-
+dpdk_conf.set('RTE_MAX_MEMSEG_LISTS', get_option('max_memseg_lists'))
+if get_option('atomic_mbuf_ref_counts')
+  dpdk_conf.set('RTE_MBUF_REFCNT_ATOMIC', true)
+endif
 
 compile_time_cpuflags = []
 subdir(arch_subdir)
diff --git a/config/rte_config.h b/config/rte_config.h
index 590903c07d..0a659f5e1a 100644
--- a/config/rte_config.h
+++ b/config/rte_config.h
@@ -29,7 +29,6 @@
 
 /* EAL defines */
 #define RTE_MAX_HEAPS 32
-#define RTE_MAX_MEMSEG_LISTS 128
 #define RTE_MAX_MEMSEG_PER_LIST 8192
 #define RTE_MAX_MEM_MB_PER_LIST 32768
 #define RTE_MAX_MEMSEG_PER_TYPE 32768
@@ -50,7 +49,6 @@
 
 /* mbuf defines */
 #define RTE_MBUF_DEFAULT_MEMPOOL_OPS "ring_mp_mc"
-#define RTE_MBUF_REFCNT_ATOMIC 1
 #define RTE_PKTMBUF_HEADROOM 128
 
 /* ether defines */
diff --git a/meson_options.txt b/meson_options.txt
index 0e92734c49..6aeae211cd 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -38,6 +38,10 @@ option('max_lcores', type: 'integer', value: 128, description:
        'maximum number of cores/threads supported by EAL')
 option('max_numa_nodes', type: 'integer', value: 32, description:
        'maximum number of NUMA nodes supported by EAL')
+option('max_memseg_lists', type: 'integer', value: 128, description:
+       'maximum number of dynamic arrays holding memsegs')
+option('atomic_mbuf_ref_counts', type: 'boolean', value: true, description:
+       'atomically access the mbuf refcnt')
 option('platform', type: 'string', value: 'native', description:
        'Platform to build, either "native", "generic" or a SoC. Please refer to the Linux build guide for more information.')
 option('enable_trace_fp', type: 'boolean', value: false, description:
-- 
2.33.0