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-rw-r--r--mm/thrash.c106
1 files changed, 0 insertions, 106 deletions
diff --git a/mm/thrash.c b/mm/thrash.c
deleted file mode 100644
index f4c560b4a2b..00000000000
--- a/mm/thrash.c
+++ /dev/null
@@ -1,106 +0,0 @@
-/*
- * mm/thrash.c
- *
- * Copyright (C) 2004, Red Hat, Inc.
- * Copyright (C) 2004, Rik van Riel <riel@redhat.com>
- * Released under the GPL, see the file COPYING for details.
- *
- * Simple token based thrashing protection, using the algorithm
- * described in: http://www.cs.wm.edu/~sjiang/token.pdf
- */
-#include <linux/jiffies.h>
-#include <linux/mm.h>
-#include <linux/sched.h>
-#include <linux/swap.h>
-
-static DEFINE_SPINLOCK(swap_token_lock);
-static unsigned long swap_token_timeout;
-static unsigned long swap_token_check;
-struct mm_struct * swap_token_mm = &init_mm;
-
-#define SWAP_TOKEN_CHECK_INTERVAL (HZ * 2)
-#define SWAP_TOKEN_TIMEOUT (300 * HZ)
-/*
- * Currently disabled; Needs further code to work at HZ * 300.
- */
-unsigned long swap_token_default_timeout = SWAP_TOKEN_TIMEOUT;
-
-/*
- * Take the token away if the process had no page faults
- * in the last interval, or if it has held the token for
- * too long.
- */
-#define SWAP_TOKEN_ENOUGH_RSS 1
-#define SWAP_TOKEN_TIMED_OUT 2
-static int should_release_swap_token(struct mm_struct *mm)
-{
- int ret = 0;
- if (!mm->recent_pagein)
- ret = SWAP_TOKEN_ENOUGH_RSS;
- else if (time_after(jiffies, swap_token_timeout))
- ret = SWAP_TOKEN_TIMED_OUT;
- mm->recent_pagein = 0;
- return ret;
-}
-
-/*
- * Try to grab the swapout protection token. We only try to
- * grab it once every TOKEN_CHECK_INTERVAL, both to prevent
- * SMP lock contention and to check that the process that held
- * the token before is no longer thrashing.
- */
-void grab_swap_token(void)
-{
- struct mm_struct *mm;
- int reason;
-
- /* We have the token. Let others know we still need it. */
- if (has_swap_token(current->mm)) {
- current->mm->recent_pagein = 1;
- if (unlikely(!swap_token_default_timeout))
- disable_swap_token();
- return;
- }
-
- if (time_after(jiffies, swap_token_check)) {
-
- if (!swap_token_default_timeout) {
- swap_token_check = jiffies + SWAP_TOKEN_CHECK_INTERVAL;
- return;
- }
-
- /* ... or if we recently held the token. */
- if (time_before(jiffies, current->mm->swap_token_time))
- return;
-
- if (!spin_trylock(&swap_token_lock))
- return;
-
- swap_token_check = jiffies + SWAP_TOKEN_CHECK_INTERVAL;
-
- mm = swap_token_mm;
- if ((reason = should_release_swap_token(mm))) {
- unsigned long eligible = jiffies;
- if (reason == SWAP_TOKEN_TIMED_OUT) {
- eligible += swap_token_default_timeout;
- }
- mm->swap_token_time = eligible;
- swap_token_timeout = jiffies + swap_token_default_timeout;
- swap_token_mm = current->mm;
- }
- spin_unlock(&swap_token_lock);
- }
- return;
-}
-
-/* Called on process exit. */
-void __put_swap_token(struct mm_struct *mm)
-{
- spin_lock(&swap_token_lock);
- if (likely(mm == swap_token_mm)) {
- mm->swap_token_time = jiffies + SWAP_TOKEN_CHECK_INTERVAL;
- swap_token_mm = &init_mm;
- swap_token_check = jiffies;
- }
- spin_unlock(&swap_token_lock);
-}