diff options
Diffstat (limited to 'mm/thrash.c')
-rw-r--r-- | mm/thrash.c | 155 |
1 files changed, 0 insertions, 155 deletions
diff --git a/mm/thrash.c b/mm/thrash.c deleted file mode 100644 index 57ad495dbd5..00000000000 --- a/mm/thrash.c +++ /dev/null @@ -1,155 +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.cse.ohio-state.edu/hpcs/WWW/HTML/publications/abs05-1.html - * - * Sep 2006, Ashwin Chaugule <ashwin.chaugule@celunite.com> - * Improved algorithm to pass token: - * Each task has a priority which is incremented if it contended - * for the token in an interval less than its previous attempt. - * If the token is acquired, that task's priority is boosted to prevent - * the token from bouncing around too often and to let the task make - * some progress in its execution. - */ - -#include <linux/jiffies.h> -#include <linux/mm.h> -#include <linux/sched.h> -#include <linux/swap.h> -#include <linux/memcontrol.h> - -#include <trace/events/vmscan.h> - -#define TOKEN_AGING_INTERVAL (0xFF) - -static DEFINE_SPINLOCK(swap_token_lock); -struct mm_struct *swap_token_mm; -static struct mem_cgroup *swap_token_memcg; - -#ifdef CONFIG_CGROUP_MEM_RES_CTLR -static struct mem_cgroup *swap_token_memcg_from_mm(struct mm_struct *mm) -{ - struct mem_cgroup *memcg; - - memcg = try_get_mem_cgroup_from_mm(mm); - if (memcg) - css_put(mem_cgroup_css(memcg)); - - return memcg; -} -#else -static struct mem_cgroup *swap_token_memcg_from_mm(struct mm_struct *mm) -{ - return NULL; -} -#endif - -void grab_swap_token(struct mm_struct *mm) -{ - int current_interval; - unsigned int old_prio = mm->token_priority; - static unsigned int global_faults; - static unsigned int last_aging; - - global_faults++; - - current_interval = global_faults - mm->faultstamp; - - if (!spin_trylock(&swap_token_lock)) - return; - - /* First come first served */ - if (!swap_token_mm) - goto replace_token; - - /* - * Usually, we don't need priority aging because long interval faults - * makes priority decrease quickly. But there is one exception. If the - * token owner task is sleeping, it never make long interval faults. - * Thus, we need a priority aging mechanism instead. The requirements - * of priority aging are - * 1) An aging interval is reasonable enough long. Too short aging - * interval makes quick swap token lost and decrease performance. - * 2) The swap token owner task have to get priority aging even if - * it's under sleep. - */ - if ((global_faults - last_aging) > TOKEN_AGING_INTERVAL) { - swap_token_mm->token_priority /= 2; - last_aging = global_faults; - } - - if (mm == swap_token_mm) { - mm->token_priority += 2; - goto update_priority; - } - - if (current_interval < mm->last_interval) - mm->token_priority++; - else { - if (likely(mm->token_priority > 0)) - mm->token_priority--; - } - - /* Check if we deserve the token */ - if (mm->token_priority > swap_token_mm->token_priority) - goto replace_token; - -update_priority: - trace_update_swap_token_priority(mm, old_prio, swap_token_mm); - -out: - mm->faultstamp = global_faults; - mm->last_interval = current_interval; - spin_unlock(&swap_token_lock); - return; - -replace_token: - mm->token_priority += 2; - trace_replace_swap_token(swap_token_mm, mm); - swap_token_mm = mm; - swap_token_memcg = swap_token_memcg_from_mm(mm); - last_aging = global_faults; - goto out; -} - -/* Called on process exit. */ -void __put_swap_token(struct mm_struct *mm) -{ - spin_lock(&swap_token_lock); - if (likely(mm == swap_token_mm)) { - trace_put_swap_token(swap_token_mm); - swap_token_mm = NULL; - swap_token_memcg = NULL; - } - spin_unlock(&swap_token_lock); -} - -static bool match_memcg(struct mem_cgroup *a, struct mem_cgroup *b) -{ - if (!a) - return true; - if (!b) - return true; - if (a == b) - return true; - return false; -} - -void disable_swap_token(struct mem_cgroup *memcg) -{ - /* memcg reclaim don't disable unrelated mm token. */ - if (match_memcg(memcg, swap_token_memcg)) { - spin_lock(&swap_token_lock); - if (match_memcg(memcg, swap_token_memcg)) { - trace_disable_swap_token(swap_token_mm); - swap_token_mm = NULL; - swap_token_memcg = NULL; - } - spin_unlock(&swap_token_lock); - } -} |