-/*
- * Distributed under the terms of the GNU GPL version 2.
- * Copyright (c) 2010, 2011 Nicira Networks.
- *
- * Significant portions of this file may be copied from parts of the Linux
- * kernel, by Linus Torvalds and others.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/hardirq.h>
-#include <linux/kernel.h>
-#include <linux/percpu.h>
-#include <linux/sched.h>
-
-#include "loop_counter.h"
-
-int loop_suppress(struct datapath *dp, struct sw_flow_actions *actions)
-{
- if (net_ratelimit())
- pr_warn("%s: flow looped %d times, dropping\n",
- dp_name(dp), MAX_LOOPS);
- actions->actions_len = 0;
- return -ELOOP;
-}
-
-#ifndef CONFIG_PREEMPT_RT
-
-/* We use a separate counter for each CPU for both interrupt and non-interrupt
- * context in order to keep the limit deterministic for a given packet.
- */
-struct percpu_loop_counters {
- struct loop_counter counters[2];
-};
-
-static DEFINE_PER_CPU(struct percpu_loop_counters, loop_counters);
-
-struct loop_counter *loop_get_counter(void)
-{
- return &get_cpu_var(loop_counters).counters[!!in_interrupt()];
-}
-
-void loop_put_counter(void)
-{
- put_cpu_var(loop_counters);
-}
-
-#else /* !CONFIG_PREEMPT_RT */
-
-struct loop_counter *loop_get_counter(void)
-{
- WARN_ON(in_interrupt());
-
- /* Only two bits of the extra_flags field in struct task_struct are
- * used and it's an unsigned int. We hijack the most significant bits
- * to be our counter structure. On RT kernels softirqs always run in
- * process context so we are guaranteed to have a valid task_struct.
- */
-
-#ifdef __LITTLE_ENDIAN
- return (void *)(¤t->extra_flags + 1) -
- sizeof(struct loop_counter);
-#elif __BIG_ENDIAN
- return (struct loop_counter *)¤t->extra_flags;
-#else
-#error "Please fix <asm/byteorder.h>."
-#endif
-}
-
-void loop_put_counter(void) { }
-
-#endif /* CONFIG_PREEMPT_RT */