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 <gage.e...@intel.com>
Suggested-by: Jerin Jacob <jer...@marvell.com>
Signed-off-by: Phil Yang <phil.y...@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
Tested-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
Acked-by: Jerin Jacob <jer...@marvell.com>
---
doc/guides/prog_guide/env_abstraction_layer.rst | 4 +--
doc/guides/rel_notes/release_19_11.rst | 3 ++
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, 55 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 94f30fd..6e59fae 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 8490d89..60ffd70 100644
--- a/doc/guides/rel_notes/release_19_11.rst
+++ b/doc/guides/rel_notes/release_19_11.rst
@@ -56,6 +56,9 @@ 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.
Removed Items
-------------
diff --git a/lib/librte_stack/Makefile b/lib/librte_stack/Makefile
index 8d18ce5..c337ab7 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 f5581f0..e67630c 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 3d677ae..999359f 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 3182151..3abbb53 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 0000000..a05abf1
--- /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 <rte_common.h>
+
+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_ */
--
2.7.4
