Vladimir Medvedkin, Sep 06, 2024 at 13:09:
Currently, for DIR24-8 algorithm, the tbl8 group is freed even though the
readers might be using the tbl8 group entries. The freed tbl8 group can
be reallocated quickly. As a result, lookup may be performed incorrectly.
To address that, RCU QSBR is integrated for safe tbl8 group reclamation.
Signed-off-by: Vladimir Medvedkin <vladimir.medved...@intel.com>
---
diff --git a/lib/fib/meson.build b/lib/fib/meson.build
index 6795f41a0a..1895f37050 100644
--- a/lib/fib/meson.build
+++ b/lib/fib/meson.build
@@ -11,6 +11,7 @@ endif
sources = files('rte_fib.c', 'rte_fib6.c', 'dir24_8.c', 'trie.c')
headers = files('rte_fib.h', 'rte_fib6.h')
deps += ['rib']
+deps += ['rcu']
Hi Vladimir,
thanks a lot for working on this!
I tested with static linking and there is a missing dependency to
static_rte_rcu:
In file included from ../subprojects/dpdk/lib/fib/dir24_8_avx512.c:6:
../subprojects/dpdk/lib/fib/rte_fib.h:19:10: fatal error: rte_rcu_qsbr.h: No
such file or directory
19 | #include <rte_rcu_qsbr.h>
| ^~~~~~~~~~~~~~~~
After adding it:
@@ -45,7 +45,7 @@ if dpdk_conf.has('RTE_ARCH_X86_64') and binutils_ok
elif cc.has_multi_arguments('-mavx512f', '-mavx512dq')
dir24_8_avx512_tmp = static_library('dir24_8_avx512_tmp',
'dir24_8_avx512.c',
- dependencies: static_rte_eal,
+ dependencies: [static_rte_eal, static_rte_rcu],
c_args: cflags + ['-mavx512f', '-mavx512dq'])
objs += dir24_8_avx512_tmp.extract_objects('dir24_8_avx512.c')
cflags += ['-DCC_DIR24_8_AVX512_SUPPORT']
I get another error:
In file included from
/usr/lib/gcc/x86_64-redhat-linux/14/include/immintrin.h:65,
from /usr/lib/gcc/x86_64-redhat-linux/14/include/x86intrin.h:32,
from ../subprojects/dpdk/lib/eal/x86/include/rte_vect.h:26,
from ../subprojects/dpdk/lib/fib/dir24_8_avx512.c:5:
/usr/lib/gcc/x86_64-redhat-linux/14/include/avx512bwintrin.h: In function
‘dir24_8_vec_lookup_x16’:
/usr/lib/gcc/x86_64-redhat-linux/14/include/avx512bwintrin.h:1947:1: error:
inlining failed in call to ‘always_inline’ ‘_mm512_shuffle_epi8’: target
specific option mismatch
1947 | _mm512_shuffle_epi8 (__m512i __A, __m512i __B)
| ^~~~~~~~~~~~~~~~~~~
../subprojects/dpdk/lib/fib/dir24_8_avx512.c:38:26: note: called from here
38 | ip_vec = _mm512_shuffle_epi8(ip_vec, bswap32);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/lib/gcc/x86_64-redhat-linux/14/include/avx512bwintrin.h:1947:1: error:
inlining failed in call to ‘always_inline’ ‘_mm512_shuffle_epi8’: target
specific option mismatch
1947 | _mm512_shuffle_epi8 (__m512i __A, __m512i __B)
| ^~~~~~~~~~~~~~~~~~~
../subprojects/dpdk/lib/fib/dir24_8_avx512.c:38:26: note: called from here
38 | ip_vec = _mm512_shuffle_epi8(ip_vec, bswap32);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I'm not sure what to do at this point.
