ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/kernel/rcu/srcutiny.c b/marvell/linux/kernel/rcu/srcutiny.c
new file mode 100644
index 0000000..44d6606
--- /dev/null
+++ b/marvell/linux/kernel/rcu/srcutiny.c
@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Sleepable Read-Copy Update mechanism for mutual exclusion,
+ * tiny version for non-preemptible single-CPU use.
+ *
+ * Copyright (C) IBM Corporation, 2017
+ *
+ * Author: Paul McKenney <paulmck@linux.ibm.com>
+ */
+
+#include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/preempt.h>
+#include <linux/rcupdate_wait.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/srcu.h>
+
+#include <linux/rcu_node_tree.h>
+#include "rcu_segcblist.h"
+#include "rcu.h"
+
+int rcu_scheduler_active __read_mostly;
+static LIST_HEAD(srcu_boot_list);
+static bool srcu_init_done;
+
+static int init_srcu_struct_fields(struct srcu_struct *ssp)
+{
+ ssp->srcu_lock_nesting[0] = 0;
+ ssp->srcu_lock_nesting[1] = 0;
+ init_swait_queue_head(&ssp->srcu_wq);
+ ssp->srcu_cb_head = NULL;
+ ssp->srcu_cb_tail = &ssp->srcu_cb_head;
+ ssp->srcu_gp_running = false;
+ ssp->srcu_gp_waiting = false;
+ ssp->srcu_idx = 0;
+ INIT_WORK(&ssp->srcu_work, srcu_drive_gp);
+ INIT_LIST_HEAD(&ssp->srcu_work.entry);
+ return 0;
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+int __init_srcu_struct(struct srcu_struct *ssp, const char *name,
+ struct lock_class_key *key)
+{
+ /* Don't re-initialize a lock while it is held. */
+ debug_check_no_locks_freed((void *)ssp, sizeof(*ssp));
+ lockdep_init_map(&ssp->dep_map, name, key, 0);
+ return init_srcu_struct_fields(ssp);
+}
+EXPORT_SYMBOL_GPL(__init_srcu_struct);
+
+#else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
+/*
+ * init_srcu_struct - initialize a sleep-RCU structure
+ * @ssp: structure to initialize.
+ *
+ * Must invoke this on a given srcu_struct before passing that srcu_struct
+ * to any other function. Each srcu_struct represents a separate domain
+ * of SRCU protection.
+ */
+int init_srcu_struct(struct srcu_struct *ssp)
+{
+ return init_srcu_struct_fields(ssp);
+}
+EXPORT_SYMBOL_GPL(init_srcu_struct);
+
+#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
+/*
+ * cleanup_srcu_struct - deconstruct a sleep-RCU structure
+ * @ssp: structure to clean up.
+ *
+ * Must invoke this after you are finished using a given srcu_struct that
+ * was initialized via init_srcu_struct(), else you leak memory.
+ */
+void cleanup_srcu_struct(struct srcu_struct *ssp)
+{
+ WARN_ON(ssp->srcu_lock_nesting[0] || ssp->srcu_lock_nesting[1]);
+ flush_work(&ssp->srcu_work);
+ WARN_ON(ssp->srcu_gp_running);
+ WARN_ON(ssp->srcu_gp_waiting);
+ WARN_ON(ssp->srcu_cb_head);
+ WARN_ON(&ssp->srcu_cb_head != ssp->srcu_cb_tail);
+}
+EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
+
+/*
+ * Removes the count for the old reader from the appropriate element of
+ * the srcu_struct.
+ */
+void __srcu_read_unlock(struct srcu_struct *ssp, int idx)
+{
+ int newval = ssp->srcu_lock_nesting[idx] - 1;
+
+ WRITE_ONCE(ssp->srcu_lock_nesting[idx], newval);
+ if (!newval && READ_ONCE(ssp->srcu_gp_waiting))
+ swake_up_one(&ssp->srcu_wq);
+}
+EXPORT_SYMBOL_GPL(__srcu_read_unlock);
+
+/*
+ * Workqueue handler to drive one grace period and invoke any callbacks
+ * that become ready as a result. Single-CPU and !PREEMPT operation
+ * means that we get away with murder on synchronization. ;-)
+ */
+void srcu_drive_gp(struct work_struct *wp)
+{
+ int idx;
+ struct rcu_head *lh;
+ struct rcu_head *rhp;
+ struct srcu_struct *ssp;
+
+ ssp = container_of(wp, struct srcu_struct, srcu_work);
+ if (ssp->srcu_gp_running || !READ_ONCE(ssp->srcu_cb_head))
+ return; /* Already running or nothing to do. */
+
+ /* Remove recently arrived callbacks and wait for readers. */
+ WRITE_ONCE(ssp->srcu_gp_running, true);
+ local_irq_disable();
+ lh = ssp->srcu_cb_head;
+ ssp->srcu_cb_head = NULL;
+ ssp->srcu_cb_tail = &ssp->srcu_cb_head;
+ local_irq_enable();
+ idx = ssp->srcu_idx;
+ WRITE_ONCE(ssp->srcu_idx, !ssp->srcu_idx);
+ WRITE_ONCE(ssp->srcu_gp_waiting, true); /* srcu_read_unlock() wakes! */
+ swait_event_exclusive(ssp->srcu_wq, !READ_ONCE(ssp->srcu_lock_nesting[idx]));
+ WRITE_ONCE(ssp->srcu_gp_waiting, false); /* srcu_read_unlock() cheap. */
+
+ /* Invoke the callbacks we removed above. */
+ while (lh) {
+ rhp = lh;
+ lh = lh->next;
+ local_bh_disable();
+ rhp->func(rhp);
+ local_bh_enable();
+ }
+
+ /*
+ * Enable rescheduling, and if there are more callbacks,
+ * reschedule ourselves. This can race with a call_srcu()
+ * at interrupt level, but the ->srcu_gp_running checks will
+ * straighten that out.
+ */
+ WRITE_ONCE(ssp->srcu_gp_running, false);
+ if (READ_ONCE(ssp->srcu_cb_head))
+ schedule_work(&ssp->srcu_work);
+}
+EXPORT_SYMBOL_GPL(srcu_drive_gp);
+
+/*
+ * Enqueue an SRCU callback on the specified srcu_struct structure,
+ * initiating grace-period processing if it is not already running.
+ */
+void call_srcu(struct srcu_struct *ssp, struct rcu_head *rhp,
+ rcu_callback_t func)
+{
+ unsigned long flags;
+
+ rhp->func = func;
+ rhp->next = NULL;
+ local_irq_save(flags);
+ *ssp->srcu_cb_tail = rhp;
+ ssp->srcu_cb_tail = &rhp->next;
+ local_irq_restore(flags);
+ if (!READ_ONCE(ssp->srcu_gp_running)) {
+ if (likely(srcu_init_done))
+ schedule_work(&ssp->srcu_work);
+ else if (list_empty(&ssp->srcu_work.entry))
+ list_add(&ssp->srcu_work.entry, &srcu_boot_list);
+ }
+}
+EXPORT_SYMBOL_GPL(call_srcu);
+
+/*
+ * synchronize_srcu - wait for prior SRCU read-side critical-section completion
+ */
+void synchronize_srcu(struct srcu_struct *ssp)
+{
+ struct rcu_synchronize rs;
+
+ init_rcu_head_on_stack(&rs.head);
+ init_completion(&rs.completion);
+ call_srcu(ssp, &rs.head, wakeme_after_rcu);
+ wait_for_completion(&rs.completion);
+ destroy_rcu_head_on_stack(&rs.head);
+}
+EXPORT_SYMBOL_GPL(synchronize_srcu);
+
+/* Lockdep diagnostics. */
+void __init rcu_scheduler_starting(void)
+{
+ rcu_scheduler_active = RCU_SCHEDULER_RUNNING;
+}
+
+/*
+ * Queue work for srcu_struct structures with early boot callbacks.
+ * The work won't actually execute until the workqueue initialization
+ * phase that takes place after the scheduler starts.
+ */
+void __init srcu_init(void)
+{
+ struct srcu_struct *ssp;
+
+ srcu_init_done = true;
+ while (!list_empty(&srcu_boot_list)) {
+ ssp = list_first_entry(&srcu_boot_list,
+ struct srcu_struct, srcu_work.entry);
+ list_del_init(&ssp->srcu_work.entry);
+ schedule_work(&ssp->srcu_work);
+ }
+}