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From: Phil Yang <phil.yang@arm.com>
To: dev@dpdk.org
Cc: thomas@monjalon.net, jerinj@marvell.com, gage.eads@intel.com,
	hemant.agrawal@nxp.com, Honnappa.Nagarahalli@arm.com,
	gavin.hu@arm.com, nd@arm.com
Subject: [dpdk-dev] [PATCH v5 3/3] eal/stack: enable lock-free stack for aarch64
Date: Mon, 22 Jul 2019 21:06:14 +0800	[thread overview]
Message-ID: <1563800774-2710-3-git-send-email-phil.yang@arm.com> (raw)
In-Reply-To: <1563800774-2710-1-git-send-email-phil.yang@arm.com>

Enable both c11 atomic and non c11 atomic lock-free stack for aarch64.

Introduced a new header, rte_stack_lf_stubs.h, 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.eads@intel.com>
Suggested-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: Phil Yang <phil.yang@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Tested-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>

---
 doc/guides/prog_guide/env_abstraction_layer.rst |  4 +-
 doc/guides/rel_notes/release_19_08.rst          |  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           | 59 +++++++++++++++++++++++++
 6 files changed, 68 insertions(+), 34 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 f15bcd9..d569f95 100644
--- a/doc/guides/prog_guide/env_abstraction_layer.rst
+++ b/doc/guides/prog_guide/env_abstraction_layer.rst
@@ -592,8 +592,8 @@ 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_08.rst b/doc/guides/rel_notes/release_19_08.rst
index 0a3f840..25d45c1 100644
--- a/doc/guides/rel_notes/release_19_08.rst
+++ b/doc/guides/rel_notes/release_19_08.rst
@@ -212,6 +212,9 @@ New Features
 
   Added multiple cores feature to compression perf tool application.
 
+* **Added Lock-free Stack for aarch64.**
+
+  The lock-free stack implementation is enabled for aarch64 platforms.
 
 Removed Items
 -------------
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..d924bc6
--- /dev/null
+++ b/lib/librte_stack/rte_stack_lf_stubs.h
@@ -0,0 +1,59 @@
+/* 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>
+#include <rte_atomic.h>
+
+static __rte_always_inline unsigned int
+__rte_stack_lf_count(struct rte_stack *s)
+{
+	/* stack_lf_push() and stack_lf_pop() do not update the list's contents
+	 * and stack_lf->len atomically, which can cause the list to appear
+	 * shorter than it actually is if this function is called while other
+	 * threads are modifying the list.
+	 *
+	 * However, given the inherently approximate nature of the get_count
+	 * callback -- even if the list and its size were updated atomically,
+	 * the size could change between when get_count executes and when the
+	 * value is returned to the caller -- this is acceptable.
+	 *
+	 * The stack_lf->len updates are placed such that the list may appear to
+	 * have fewer elements than it does, but will never appear to have more
+	 * elements. If the mempool is near-empty to the point that this is a
+	 * concern, the user should consider increasing the mempool size.
+	 */
+	return (unsigned int)rte_atomic64_read((rte_atomic64_t *)
+			&s->stack_lf.used.len);
+}
+
+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


  parent reply	other threads:[~2019-07-22 13:07 UTC|newest]

Thread overview: 88+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-23  2:41 [dpdk-dev] [PATCH v1 1/3] eal/arm64: add 128-bit atomic compare exchange Phil Yang
2019-06-23  2:41 ` [dpdk-dev] [PATCH v1 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-06-23  2:41 ` [dpdk-dev] [PATCH v1 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-06-23  3:15 ` [dpdk-dev] [PATCH v2 1/3] eal/arm64: add 128-bit atomic compare exchange Phil Yang
2019-06-23  3:15   ` [dpdk-dev] [PATCH v2 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-06-24 15:09     ` Eads, Gage
2019-06-24 15:29       ` Phil Yang (Arm Technology China)
2019-06-23  3:15   ` [dpdk-dev] [PATCH v2 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-06-24 15:15     ` Eads, Gage
2019-06-24 15:22       ` Phil Yang (Arm Technology China)
2019-06-24 14:46   ` [dpdk-dev] [PATCH v2 1/3] eal/arm64: add 128-bit atomic compare exchange Eads, Gage
2019-06-24 15:35     ` Phil Yang (Arm Technology China)
2019-06-28  8:11 ` [dpdk-dev] [PATCH v3 " Phil Yang
2019-06-28  8:11   ` [dpdk-dev] [PATCH v3 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-06-29  0:17     ` Eads, Gage
2019-07-19  4:03     ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-06-28  8:11   ` [dpdk-dev] [PATCH v3 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-06-29  0:18     ` Eads, Gage
2019-07-19  4:18     ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-19  4:42       ` Eads, Gage
2019-07-19  5:02         ` Jerin Jacob Kollanukkaran
2019-07-19  5:15           ` Phil Yang (Arm Technology China)
2019-07-03 12:25   ` [dpdk-dev] [EXT] [PATCH v3 1/3] eal/arm64: add 128-bit atomic compare exchange Jerin Jacob Kollanukkaran
2019-07-03 13:07     ` Jerin Jacob Kollanukkaran
2019-07-05  4:20       ` Honnappa Nagarahalli
2019-07-05  4:37         ` Pavan Nikhilesh Bhagavatula
2019-07-09  9:27           ` Phil Yang (Arm Technology China)
2019-07-09 11:14             ` Jerin Jacob Kollanukkaran
2019-07-19  6:24   ` Jerin Jacob Kollanukkaran
2019-07-19 11:01     ` Phil Yang (Arm Technology China)
2019-07-19 12:35       ` Jerin Jacob Kollanukkaran
2019-07-19 13:56         ` Phil Yang (Arm Technology China)
2019-07-19 14:50           ` Eads, Gage
2019-07-22  8:44 ` [dpdk-dev] [PATCH v4 " Phil Yang
2019-07-22  8:44   ` [dpdk-dev] [PATCH v4 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-07-22  8:44   ` [dpdk-dev] [PATCH v4 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-07-22 10:22     ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-22 11:51       ` Phil Yang (Arm Technology China)
2019-07-22 10:20   ` [dpdk-dev] [EXT] [PATCH v4 1/3] eal/arm64: add 128-bit atomic compare exchange Jerin Jacob Kollanukkaran
2019-07-22 11:50     ` Phil Yang (Arm Technology China)
2019-07-22 13:06 ` [dpdk-dev] [PATCH v5 " Phil Yang
2019-07-22 13:06   ` [dpdk-dev] [PATCH v5 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-07-22 13:06   ` Phil Yang [this message]
2019-07-22 14:14     ` [dpdk-dev] [EXT] [PATCH v5 3/3] eal/stack: enable lock-free stack for aarch64 Jerin Jacob Kollanukkaran
2019-07-22 15:19       ` Phil Yang (Arm Technology China)
2019-07-22 14:34     ` [dpdk-dev] " Eads, Gage
2019-07-22 14:43       ` Phil Yang (Arm Technology China)
2019-07-22 14:19   ` [dpdk-dev] [EXT] [PATCH v5 1/3] eal/arm64: add 128-bit atomic compare exchange Jerin Jacob Kollanukkaran
2019-07-22 16:23     ` Phil Yang (Arm Technology China)
2019-07-22 16:22 ` [dpdk-dev] [PATCH v6 " Phil Yang
2019-07-22 16:22   ` [dpdk-dev] [PATCH v6 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-07-22 16:22   ` [dpdk-dev] [PATCH v6 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-07-22 16:59     ` [dpdk-dev] [EXT] " Jerin Jacob Kollanukkaran
2019-07-22 16:57   ` [dpdk-dev] [EXT] [PATCH v6 1/3] eal/arm64: add 128-bit atomic compare exchange Jerin Jacob Kollanukkaran
2019-07-23  3:28     ` Phil Yang (Arm Technology China)
2019-07-23  7:09       ` Jerin Jacob Kollanukkaran
2019-07-23  7:53         ` Phil Yang (Arm Technology China)
2019-07-23  5:57 ` [dpdk-dev] [PATCH v7 " Phil Yang
2019-07-23  5:57   ` [dpdk-dev] [PATCH v7 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-07-23  5:57   ` [dpdk-dev] [PATCH v7 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-07-23  7:05   ` [dpdk-dev] [PATCH v8 1/3] eal/arm64: add 128-bit atomic compare exchange jerinj
2019-07-23  7:05     ` [dpdk-dev] [PATCH v8 2/3] test/atomic: add 128b compare and swap test jerinj
2019-07-23  7:05     ` [dpdk-dev] [PATCH v8 3/3] eal/stack: enable lock-free stack for aarch64 jerinj
2019-08-14  8:27     ` [dpdk-dev] [PATCH v9 1/3] eal/arm64: add 128-bit atomic compare exchange Phil Yang
2019-08-14  8:27       ` [dpdk-dev] [PATCH v9 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-10-14 15:45         ` David Marchand
2019-10-15 11:32           ` Phil Yang (Arm Technology China)
2019-08-14  8:27       ` [dpdk-dev] [PATCH v9 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-10-14 15:45         ` David Marchand
2019-10-15 11:32           ` Phil Yang (Arm Technology China)
2019-10-14 15:43       ` [dpdk-dev] [PATCH v9 1/3] eal/arm64: add 128-bit atomic compare exchange David Marchand
2019-10-15 11:32         ` Phil Yang (Arm Technology China)
2019-10-15 12:16           ` David Marchand
2019-10-16  9:04             ` Phil Yang (Arm Technology China)
2019-10-17 12:45               ` David Marchand
2019-10-15 11:38       ` [dpdk-dev] [PATCH v10 " Phil Yang
2019-10-15 11:38         ` [dpdk-dev] [PATCH v10 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-10-15 11:38         ` [dpdk-dev] [PATCH v10 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-10-18 11:21         ` [dpdk-dev] [PATCH v11 1/3] eal/arm64: add 128-bit atomic compare exchange Phil Yang
2019-10-18 11:21           ` [dpdk-dev] [PATCH v11 2/3] test/atomic: add 128b compare and swap test Phil Yang
2019-10-21  8:25             ` David Marchand
2019-10-18 11:21           ` [dpdk-dev] [PATCH v11 3/3] eal/stack: enable lock-free stack for aarch64 Phil Yang
2019-10-21  8:26             ` David Marchand
2019-10-18 14:16           ` [dpdk-dev] [PATCH v11 1/3] eal/arm64: add 128-bit atomic compare exchange David Marchand
2019-10-18 14:24             ` Jerin Jacob
2019-10-18 14:33               ` David Marchand
2019-10-18 14:36                 ` Jerin Jacob
2019-10-21  8:24                   ` David Marchand

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