1 files changed, 357 insertions, 0 deletions
diff --git a/include/ck_stack.h b/include/ck_stack.h
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--- /dev/null
+++ b/include/ck_stack.h
@@ -0,0 +1,357 @@
+/*
+ * Copyright 2009-2015 Samy Al Bahra.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef CK_STACK_H
+#define CK_STACK_H
+
+#include <ck_cc.h>
+#include <ck_pr.h>
+#include <ck_stdbool.h>
+#include <ck_stddef.h>
+
+struct ck_stack_entry {
+	struct ck_stack_entry *next;
+};
+typedef struct ck_stack_entry ck_stack_entry_t;
+
+struct ck_stack {
+	struct ck_stack_entry *head;
+	char *generation CK_CC_PACKED;
+} CK_CC_ALIASED;
+typedef struct ck_stack ck_stack_t;
+
+#define CK_STACK_INITIALIZER { NULL, NULL }
+
+#ifndef CK_F_STACK_PUSH_UPMC
+#define CK_F_STACK_PUSH_UPMC
+/*
+ * Stack producer operation safe for multiple unique producers and multiple consumers.
+ */
+CK_CC_INLINE static void
+ck_stack_push_upmc(struct ck_stack *target, struct ck_stack_entry *entry)
+{
+	struct ck_stack_entry *stack;
+
+	stack = ck_pr_load_ptr(&target->head);
+	entry->next = stack;
+	ck_pr_fence_store();
+
+	while (ck_pr_cas_ptr_value(&target->head, stack, entry, &stack) == false) {
+		entry->next = stack;
+		ck_pr_fence_store();
+	}
+
+	return;
+}
+#endif /* CK_F_STACK_PUSH_UPMC */
+
+#ifndef CK_F_STACK_TRYPUSH_UPMC
+#define CK_F_STACK_TRYPUSH_UPMC
+/*
+ * Stack producer operation for multiple unique producers and multiple consumers.
+ * Returns true on success and false on failure.
+ */
+CK_CC_INLINE static bool
+ck_stack_trypush_upmc(struct ck_stack *target, struct ck_stack_entry *entry)
+{
+	struct ck_stack_entry *stack;
+
+	stack = ck_pr_load_ptr(&target->head);
+	entry->next = stack;
+	ck_pr_fence_store();
+
+	return ck_pr_cas_ptr(&target->head, stack, entry);
+}
+#endif /* CK_F_STACK_TRYPUSH_UPMC */
+
+#ifndef CK_F_STACK_POP_UPMC
+#define CK_F_STACK_POP_UPMC
+/*
+ * Stack consumer operation safe for multiple unique producers and multiple consumers.
+ */
+CK_CC_INLINE static struct ck_stack_entry *
+ck_stack_pop_upmc(struct ck_stack *target)
+{
+	struct ck_stack_entry *entry, *next;
+
+	entry = ck_pr_load_ptr(&target->head);
+	if (entry == NULL)
+		return NULL;
+
+	ck_pr_fence_load();
+	next = entry->next;
+	while (ck_pr_cas_ptr_value(&target->head, entry, next, &entry) == false) {
+		if (entry == NULL)
+			break;
+
+		ck_pr_fence_load();
+		next = entry->next;
+	}
+
+	return entry;
+}
+#endif
+
+#ifndef CK_F_STACK_TRYPOP_UPMC
+#define CK_F_STACK_TRYPOP_UPMC
+/*
+ * Stack production operation for multiple unique producers and multiple consumers.
+ * Returns true on success and false on failure. The value pointed to by the second
+ * argument is set to a valid ck_stack_entry_t reference if true is returned. If
+ * false is returned, then the value pointed to by the second argument is undefined.
+ */
+CK_CC_INLINE static bool
+ck_stack_trypop_upmc(struct ck_stack *target, struct ck_stack_entry **r)
+{
+	struct ck_stack_entry *entry;
+
+	entry = ck_pr_load_ptr(&target->head);
+	if (entry == NULL)
+		return false;
+
+	ck_pr_fence_load();
+	if (ck_pr_cas_ptr(&target->head, entry, entry->next) == true) {
+		*r = entry;
+		return true;
+	}
+
+	return false;
+}
+#endif /* CK_F_STACK_TRYPOP_UPMC */
+
+#ifndef CK_F_STACK_BATCH_POP_UPMC
+#define CK_F_STACK_BATCH_POP_UPMC
+/*
+ * Pop all items off the stack.
+ */
+CK_CC_INLINE static struct ck_stack_entry *
+ck_stack_batch_pop_upmc(struct ck_stack *target)
+{
+	struct ck_stack_entry *entry;
+
+	entry = ck_pr_fas_ptr(&target->head, NULL);
+	ck_pr_fence_load();
+	return entry;
+}
+#endif /* CK_F_STACK_BATCH_POP_UPMC */
+
+#ifndef CK_F_STACK_PUSH_MPMC
+#define CK_F_STACK_PUSH_MPMC
+/*
+ * Stack producer operation safe for multiple producers and multiple consumers.
+ */
+CK_CC_INLINE static void
+ck_stack_push_mpmc(struct ck_stack *target, struct ck_stack_entry *entry)
+{
+
+	ck_stack_push_upmc(target, entry);
+	return;
+}
+#endif /* CK_F_STACK_PUSH_MPMC */
+
+#ifndef CK_F_STACK_TRYPUSH_MPMC
+#define CK_F_STACK_TRYPUSH_MPMC
+/*
+ * Stack producer operation safe for multiple producers and multiple consumers.
+ */
+CK_CC_INLINE static bool
+ck_stack_trypush_mpmc(struct ck_stack *target, struct ck_stack_entry *entry)
+{
+
+	return ck_stack_trypush_upmc(target, entry);
+}
+#endif /* CK_F_STACK_TRYPUSH_MPMC */
+
+#ifdef CK_F_PR_CAS_PTR_2_VALUE
+#ifndef CK_F_STACK_POP_MPMC
+#define CK_F_STACK_POP_MPMC
+/*
+ * Stack consumer operation safe for multiple producers and multiple consumers.
+ */
+CK_CC_INLINE static struct ck_stack_entry *
+ck_stack_pop_mpmc(struct ck_stack *target)
+{
+	struct ck_stack original, update;
+
+	original.generation = ck_pr_load_ptr(&target->generation);
+	ck_pr_fence_load();
+	original.head = ck_pr_load_ptr(&target->head);
+	if (original.head == NULL)
+		return NULL;
+
+	/* Order with respect to next pointer. */
+	ck_pr_fence_load();
+
+	update.generation = original.generation + 1;
+	update.head = original.head->next;
+
+	while (ck_pr_cas_ptr_2_value(target, &original, &update, &original) == false) {
+		if (original.head == NULL)
+			return NULL;
+
+		update.generation = original.generation + 1;
+
+		/* Order with respect to next pointer. */
+		ck_pr_fence_load();
+		update.head = original.head->next;
+	}
+
+	return original.head;
+}
+#endif /* CK_F_STACK_POP_MPMC */
+
+#ifndef CK_F_STACK_TRYPOP_MPMC
+#define CK_F_STACK_TRYPOP_MPMC
+CK_CC_INLINE static bool
+ck_stack_trypop_mpmc(struct ck_stack *target, struct ck_stack_entry **r)
+{
+	struct ck_stack original, update;
+
+	original.generation = ck_pr_load_ptr(&target->generation);
+	ck_pr_fence_load();
+	original.head = ck_pr_load_ptr(&target->head);
+	if (original.head == NULL)
+		return false;
+
+	update.generation = original.generation + 1;
+	ck_pr_fence_load();
+	update.head = original.head->next;
+
+	if (ck_pr_cas_ptr_2_value(target, &original, &update, &original) == true) {
+		*r = original.head;
+		return true;
+	}
+
+	return false;
+}
+#endif /* CK_F_STACK_TRYPOP_MPMC */
+#endif /* CK_F_PR_CAS_PTR_2_VALUE */
+
+#ifndef CK_F_STACK_BATCH_POP_MPMC
+#define CK_F_STACK_BATCH_POP_MPMC
+/*
+ * This is equivalent to the UP/MC version as NULL does not need a
+ * a generation count.
+ */
+CK_CC_INLINE static struct ck_stack_entry *
+ck_stack_batch_pop_mpmc(struct ck_stack *target)
+{
+
+	return ck_stack_batch_pop_upmc(target);
+}
+#endif /* CK_F_STACK_BATCH_POP_MPMC */
+
+#ifndef CK_F_STACK_PUSH_MPNC
+#define CK_F_STACK_PUSH_MPNC
+/*
+ * Stack producer operation safe with no concurrent consumers.
+ */
+CK_CC_INLINE static void
+ck_stack_push_mpnc(struct ck_stack *target, struct ck_stack_entry *entry)
+{
+	struct ck_stack_entry *stack;
+
+	entry->next = NULL;
+	ck_pr_fence_store_atomic();
+	stack = ck_pr_fas_ptr(&target->head, entry);
+	ck_pr_store_ptr(&entry->next, stack);
+	ck_pr_fence_store();
+
+	return;
+}
+#endif /* CK_F_STACK_PUSH_MPNC */
+
+/*
+ * Stack producer operation for single producer and no concurrent consumers.
+ */
+CK_CC_INLINE static void
+ck_stack_push_spnc(struct ck_stack *target, struct ck_stack_entry *entry)
+{
+
+	entry->next = target->head;
+	target->head = entry;
+	return;
+}
+
+/*
+ * Stack consumer operation for no concurrent producers and single consumer.
+ */
+CK_CC_INLINE static struct ck_stack_entry *
+ck_stack_pop_npsc(struct ck_stack *target)
+{
+	struct ck_stack_entry *n;
+
+	if (target->head == NULL)
+		return NULL;
+
+	n = target->head;
+	target->head = n->next;
+
+	return n;
+}
+
+/*
+ * Pop all items off a stack.
+ */
+CK_CC_INLINE static struct ck_stack_entry *
+ck_stack_batch_pop_npsc(struct ck_stack *target)
+{
+	struct ck_stack_entry *n;
+
+	n = target->head;
+	target->head = NULL;
+
+	return n;
+}
+
+/*
+ * Stack initialization function. Guarantees initialization across processors.
+ */
+CK_CC_INLINE static void
+ck_stack_init(struct ck_stack *stack)
+{
+
+	stack->head = NULL;
+	stack->generation = NULL;
+	return;
+}
+
+/* Defines a container_of functions for */
+#define CK_STACK_CONTAINER(T, M, N) CK_CC_CONTAINER(ck_stack_entry_t, T, M, N)
+
+#define CK_STACK_ISEMPTY(m) ((m)->head == NULL)
+#define CK_STACK_FIRST(s)   ((s)->head)
+#define CK_STACK_NEXT(m)    ((m)->next)
+#define CK_STACK_FOREACH(stack, entry)				\
+	for ((entry) = CK_STACK_FIRST(stack);			\
+	     (entry) != NULL;					\
+	     (entry) = CK_STACK_NEXT(entry))
+#define CK_STACK_FOREACH_SAFE(stack, entry, T)			\
+	for ((entry) = CK_STACK_FIRST(stack);			\
+	     (entry) != NULL && ((T) = (entry)->next, 1);	\
+	     (entry) = (T))
+
+#endif /* CK_STACK_H */