From 7911ba0473e023d6177a7dfa6f4e2a18031c68ff Mon Sep 17 00:00:00 2001 From: Phil Yang Date: Fri, 18 Oct 2019 19:21:30 +0800 Subject: [PATCH] stack: enable lock-free implementation for aarch64 Enable both C11 atomic and non C11 atomic lock-free stack for aarch64. Introduced a new header to reduce the ifdef clutter across generic and C11 files. The rte_stack_lf_stubs.h contains stub implementations of __rte_stack_lf_count, __rte_stack_lf_push_elems and __rte_stack_lf_pop_elems. Suggested-by: Gage Eads Suggested-by: Jerin Jacob Signed-off-by: Phil Yang Reviewed-by: Honnappa Nagarahalli Tested-by: Honnappa Nagarahalli Acked-by: Jerin Jacob --- .../prog_guide/env_abstraction_layer.rst | 4 +- doc/guides/rel_notes/release_19_11.rst | 4 ++ lib/librte_stack/Makefile | 3 +- lib/librte_stack/rte_stack_lf.h | 4 ++ lib/librte_stack/rte_stack_lf_c11.h | 16 ------- lib/librte_stack/rte_stack_lf_generic.h | 16 ------- lib/librte_stack/rte_stack_lf_stubs.h | 44 +++++++++++++++++++ 7 files changed, 56 insertions(+), 35 deletions(-) create mode 100644 lib/librte_stack/rte_stack_lf_stubs.h diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst b/doc/guides/prog_guide/env_abstraction_layer.rst index 94f30fd5d6..6e59faeea9 100644 --- a/doc/guides/prog_guide/env_abstraction_layer.rst +++ b/doc/guides/prog_guide/env_abstraction_layer.rst @@ -648,8 +648,8 @@ Known Issues Alternatively, applications can use the lock-free stack mempool handler. When considering this handler, note that: - - It is currently limited to the x86_64 platform, because it uses an - instruction (16-byte compare-and-swap) that is not yet available on other + - It is currently limited to the aarch64 and x86_64 platforms, because it uses + an instruction (16-byte compare-and-swap) that is not yet available on other platforms. - It has worse average-case performance than the non-preemptive rte_ring, but software caching (e.g. the mempool cache) can mitigate this by reducing the diff --git a/doc/guides/rel_notes/release_19_11.rst b/doc/guides/rel_notes/release_19_11.rst index 85953b962d..b8386d4515 100644 --- a/doc/guides/rel_notes/release_19_11.rst +++ b/doc/guides/rel_notes/release_19_11.rst @@ -56,6 +56,10 @@ New Features Also, make sure to start the actual text at the margin. ========================================================= +* **Added Lock-free Stack for aarch64.** + + The lock-free stack implementation is enabled for aarch64 platforms. + * **Added Hisilicon hns3 PMD.** Added the new ``hns3`` net driver for the inbuilt Hisilicon Network diff --git a/lib/librte_stack/Makefile b/lib/librte_stack/Makefile index 8d18ce5204..b5e5bed7cf 100644 --- a/lib/librte_stack/Makefile +++ b/lib/librte_stack/Makefile @@ -24,6 +24,7 @@ SYMLINK-$(CONFIG_RTE_LIBRTE_STACK)-include := rte_stack.h \ rte_stack_std.h \ rte_stack_lf.h \ rte_stack_lf_generic.h \ - rte_stack_lf_c11.h + rte_stack_lf_c11.h \ + rte_stack_lf_stubs.h include $(RTE_SDK)/mk/rte.lib.mk diff --git a/lib/librte_stack/rte_stack_lf.h b/lib/librte_stack/rte_stack_lf.h index f5581f0c24..e67630c277 100644 --- a/lib/librte_stack/rte_stack_lf.h +++ b/lib/librte_stack/rte_stack_lf.h @@ -5,11 +5,15 @@ #ifndef _RTE_STACK_LF_H_ #define _RTE_STACK_LF_H_ +#if !(defined(RTE_ARCH_X86_64) || defined(RTE_ARCH_ARM64)) +#include "rte_stack_lf_stubs.h" +#else #ifdef RTE_USE_C11_MEM_MODEL #include "rte_stack_lf_c11.h" #else #include "rte_stack_lf_generic.h" #endif +#endif /** * @internal Push several objects on the lock-free stack (MT-safe). diff --git a/lib/librte_stack/rte_stack_lf_c11.h b/lib/librte_stack/rte_stack_lf_c11.h index 3d677aed1d..999359f081 100644 --- a/lib/librte_stack/rte_stack_lf_c11.h +++ b/lib/librte_stack/rte_stack_lf_c11.h @@ -36,12 +36,6 @@ __rte_stack_lf_push_elems(struct rte_stack_lf_list *list, struct rte_stack_lf_elem *last, unsigned int num) { -#ifndef RTE_ARCH_X86_64 - RTE_SET_USED(first); - RTE_SET_USED(last); - RTE_SET_USED(list); - RTE_SET_USED(num); -#else struct rte_stack_lf_head old_head; int success; @@ -79,7 +73,6 @@ __rte_stack_lf_push_elems(struct rte_stack_lf_list *list, * to the LIFO len update. */ __atomic_add_fetch(&list->len, num, __ATOMIC_RELEASE); -#endif } static __rte_always_inline struct rte_stack_lf_elem * @@ -88,14 +81,6 @@ __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list, void **obj_table, struct rte_stack_lf_elem **last) { -#ifndef RTE_ARCH_X86_64 - RTE_SET_USED(obj_table); - RTE_SET_USED(last); - RTE_SET_USED(list); - RTE_SET_USED(num); - - return NULL; -#else struct rte_stack_lf_head old_head; uint64_t len; int success; @@ -169,7 +154,6 @@ __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list, } while (success == 0); return old_head.top; -#endif } #endif /* _RTE_STACK_LF_C11_H_ */ diff --git a/lib/librte_stack/rte_stack_lf_generic.h b/lib/librte_stack/rte_stack_lf_generic.h index 31821514f0..3abbb53428 100644 --- a/lib/librte_stack/rte_stack_lf_generic.h +++ b/lib/librte_stack/rte_stack_lf_generic.h @@ -36,12 +36,6 @@ __rte_stack_lf_push_elems(struct rte_stack_lf_list *list, struct rte_stack_lf_elem *last, unsigned int num) { -#ifndef RTE_ARCH_X86_64 - RTE_SET_USED(first); - RTE_SET_USED(last); - RTE_SET_USED(list); - RTE_SET_USED(num); -#else struct rte_stack_lf_head old_head; int success; @@ -75,7 +69,6 @@ __rte_stack_lf_push_elems(struct rte_stack_lf_list *list, } while (success == 0); rte_atomic64_add((rte_atomic64_t *)&list->len, num); -#endif } static __rte_always_inline struct rte_stack_lf_elem * @@ -84,14 +77,6 @@ __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list, void **obj_table, struct rte_stack_lf_elem **last) { -#ifndef RTE_ARCH_X86_64 - RTE_SET_USED(obj_table); - RTE_SET_USED(last); - RTE_SET_USED(list); - RTE_SET_USED(num); - - return NULL; -#else struct rte_stack_lf_head old_head; int success; @@ -159,7 +144,6 @@ __rte_stack_lf_pop_elems(struct rte_stack_lf_list *list, } while (success == 0); return old_head.top; -#endif } #endif /* _RTE_STACK_LF_GENERIC_H_ */ diff --git a/lib/librte_stack/rte_stack_lf_stubs.h b/lib/librte_stack/rte_stack_lf_stubs.h new file mode 100644 index 0000000000..a05abf1f1c --- /dev/null +++ b/lib/librte_stack/rte_stack_lf_stubs.h @@ -0,0 +1,44 @@ +/* SPDX-License-Identifier: BSD-3-Clause + * Copyright(c) 2019 Arm Limited + */ + +#ifndef _RTE_STACK_LF_STUBS_H_ +#define _RTE_STACK_LF_STUBS_H_ + +#include + +static __rte_always_inline unsigned int +__rte_stack_lf_count(struct rte_stack *s) +{ + RTE_SET_USED(s); + + return 0; +} + +static __rte_always_inline void +__rte_stack_lf_push_elems(struct rte_stack_lf_list *list, + struct rte_stack_lf_elem *first, + struct rte_stack_lf_elem *last, + unsigned int num) +{ + RTE_SET_USED(first); + RTE_SET_USED(last); + RTE_SET_USED(list); + RTE_SET_USED(num); +} + +static __rte_always_inline struct rte_stack_lf_elem * +__rte_stack_lf_pop_elems(struct rte_stack_lf_list *list, + unsigned int num, + void **obj_table, + struct rte_stack_lf_elem **last) +{ + RTE_SET_USED(obj_table); + RTE_SET_USED(last); + RTE_SET_USED(list); + RTE_SET_USED(num); + + return NULL; +} + +#endif /* _RTE_STACK_LF_STUBS_H_ */