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Diffstat (limited to 'sys')
-rw-r--r--sys/include/sys/spinlock.h3
-rw-r--r--sys/kern/kern_synch.c26
2 files changed, 29 insertions, 0 deletions
diff --git a/sys/include/sys/spinlock.h b/sys/include/sys/spinlock.h
index b416152..140addc 100644
--- a/sys/include/sys/spinlock.h
+++ b/sys/include/sys/spinlock.h
@@ -44,6 +44,9 @@ void spinlock_release(struct spinlock *lock);
int spinlock_try_acquire(struct spinlock *lock);
int spinlock_usleep(struct spinlock *lock, size_t usec_max);
+/* System-wide locking (be careful!!) */
+int syslock(void);
+void sysrel(void);
#endif
#endif /* !_SYS_SPINLOCK_H_ */
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c
index 2b64673..57b27d0 100644
--- a/sys/kern/kern_synch.c
+++ b/sys/kern/kern_synch.c
@@ -38,6 +38,9 @@
#define pr_trace(fmt, ...) kprintf("synch: " fmt, ##__VA_ARGS__)
#define pr_error(...) pr_trace(__VA_ARGS__)
+/* XXX: Be very careful with this */
+static struct spinlock __syslock;
+
/*
* Returns 0 on success, returns non-zero value
* on timeout/failure.
@@ -110,3 +113,26 @@ spinlock_release(struct spinlock *lock)
{
__atomic_clear(&lock->lock, __ATOMIC_RELEASE);
}
+
+/*
+ * Attempt to hold the system-wide lock, returns 1
+ * if already held.
+ *
+ * XXX: Only use for CRITICAL code sections.
+ */
+int
+syslock(void)
+{
+ return spinlock_try_acquire(&__syslock);
+}
+
+/*
+ * Release the system-wide lock
+ *
+ * XXX: Only use for CRITICAL code sections.
+ */
+void
+sysrel(void)
+{
+ spinlock_release(&__syslock);
+}