/* Architecture-specific MM context */
mm_context_t context;
- /* Swap token stuff */
- /*
- * Last value of global fault stamp as seen by this process.
- * In other words, this value gives an indication of how long
- * it has been since this task got the token.
- * Look at mm/thrash.c
- */
- unsigned int faultstamp;
- unsigned int token_priority;
- unsigned int last_interval;
-
unsigned long flags; /* Must use atomic bitops to access the bits */
struct core_state *core_state; /* coredumping support */
extern int try_to_free_swap(struct page *);
struct backing_dev_info;
-/* linux/mm/thrash.c */
-extern struct mm_struct *swap_token_mm;
-extern void grab_swap_token(struct mm_struct *);
-extern void __put_swap_token(struct mm_struct *);
-extern void disable_swap_token(struct mem_cgroup *memcg);
-
-static inline int has_swap_token(struct mm_struct *mm)
-{
- return (mm == swap_token_mm);
-}
-
-static inline void put_swap_token(struct mm_struct *mm)
-{
- if (has_swap_token(mm))
- __put_swap_token(mm);
-}
-
#ifdef CONFIG_CGROUP_MEM_RES_CTLR
extern void
mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent, bool swapout);
return entry;
}
-/* linux/mm/thrash.c */
-static inline void put_swap_token(struct mm_struct *mm)
-{
-}
-
-static inline void grab_swap_token(struct mm_struct *mm)
-{
-}
-
-static inline int has_swap_token(struct mm_struct *mm)
-{
- return 0;
-}
-
-static inline void disable_swap_token(struct mem_cgroup *memcg)
-{
-}
-
static inline void
mem_cgroup_uncharge_swapcache(struct page *page, swp_entry_t ent)
{
show_reclaim_flags(__entry->reclaim_flags))
);
-TRACE_EVENT(replace_swap_token,
- TP_PROTO(struct mm_struct *old_mm,
- struct mm_struct *new_mm),
-
- TP_ARGS(old_mm, new_mm),
-
- TP_STRUCT__entry(
- __field(struct mm_struct*, old_mm)
- __field(unsigned int, old_prio)
- __field(struct mm_struct*, new_mm)
- __field(unsigned int, new_prio)
- ),
-
- TP_fast_assign(
- __entry->old_mm = old_mm;
- __entry->old_prio = old_mm ? old_mm->token_priority : 0;
- __entry->new_mm = new_mm;
- __entry->new_prio = new_mm->token_priority;
- ),
-
- TP_printk("old_token_mm=%p old_prio=%u new_token_mm=%p new_prio=%u",
- __entry->old_mm, __entry->old_prio,
- __entry->new_mm, __entry->new_prio)
-);
-
-DECLARE_EVENT_CLASS(put_swap_token_template,
- TP_PROTO(struct mm_struct *swap_token_mm),
-
- TP_ARGS(swap_token_mm),
-
- TP_STRUCT__entry(
- __field(struct mm_struct*, swap_token_mm)
- ),
-
- TP_fast_assign(
- __entry->swap_token_mm = swap_token_mm;
- ),
-
- TP_printk("token_mm=%p", __entry->swap_token_mm)
-);
-
-DEFINE_EVENT(put_swap_token_template, put_swap_token,
- TP_PROTO(struct mm_struct *swap_token_mm),
- TP_ARGS(swap_token_mm)
-);
-
-DEFINE_EVENT_CONDITION(put_swap_token_template, disable_swap_token,
- TP_PROTO(struct mm_struct *swap_token_mm),
- TP_ARGS(swap_token_mm),
- TP_CONDITION(swap_token_mm != NULL)
-);
-
-TRACE_EVENT_CONDITION(update_swap_token_priority,
- TP_PROTO(struct mm_struct *mm,
- unsigned int old_prio,
- struct mm_struct *swap_token_mm),
-
- TP_ARGS(mm, old_prio, swap_token_mm),
-
- TP_CONDITION(mm->token_priority != old_prio),
-
- TP_STRUCT__entry(
- __field(struct mm_struct*, mm)
- __field(unsigned int, old_prio)
- __field(unsigned int, new_prio)
- __field(struct mm_struct*, swap_token_mm)
- __field(unsigned int, swap_token_prio)
- ),
-
- TP_fast_assign(
- __entry->mm = mm;
- __entry->old_prio = old_prio;
- __entry->new_prio = mm->token_priority;
- __entry->swap_token_mm = swap_token_mm;
- __entry->swap_token_prio = swap_token_mm ? swap_token_mm->token_priority : 0;
- ),
-
- TP_printk("mm=%p old_prio=%u new_prio=%u swap_token_mm=%p token_prio=%u",
- __entry->mm, __entry->old_prio, __entry->new_prio,
- __entry->swap_token_mm, __entry->swap_token_prio)
-);
-
#endif /* _TRACE_VMSCAN_H */
/* This part must be outside protection */
list_del(&mm->mmlist);
spin_unlock(&mmlist_lock);
}
- put_swap_token(mm);
if (mm->binfmt)
module_put(mm->binfmt->module);
mmdrop(mm);
memcpy(mm, oldmm, sizeof(*mm));
mm_init_cpumask(mm);
- /* Initializing for Swap token stuff */
- mm->token_priority = 0;
- mm->last_interval = 0;
-
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
mm->pmd_huge_pte = NULL;
#endif
goto fail_nomem;
good_mm:
- /* Initializing for Swap token stuff */
- mm->token_priority = 0;
- mm->last_interval = 0;
-
tsk->mm = mm;
tsk->active_mm = mm;
return 0;
obj-$(CONFIG_HAVE_MEMBLOCK) += memblock.o
obj-$(CONFIG_BOUNCE) += bounce.o
-obj-$(CONFIG_SWAP) += page_io.o swap_state.o swapfile.o thrash.o
+obj-$(CONFIG_SWAP) += page_io.o swap_state.o swapfile.o
obj-$(CONFIG_HAS_DMA) += dmapool.o
obj-$(CONFIG_HUGETLBFS) += hugetlb.o
obj-$(CONFIG_NUMA) += mempolicy.o
if (mm) {
if (mc.to)
mem_cgroup_move_charge(mm);
- put_swap_token(mm);
mmput(mm);
}
if (mc.to)
delayacct_set_flag(DELAYACCT_PF_SWAPIN);
page = lookup_swap_cache(entry);
if (!page) {
- grab_swap_token(mm); /* Contend for token _before_ read-in */
page = swapin_readahead(entry,
GFP_HIGHUSER_MOVABLE, vma, address);
if (!page) {
}
locked = lock_page_or_retry(page, mm, flags);
+
delayacct_clear_flag(DELAYACCT_PF_SWAPIN);
if (!locked) {
ret |= VM_FAULT_RETRY;
pte_unmap_unlock(pte, ptl);
}
- /* Pretend the page is referenced if the task has the
- swap token and is in the middle of a page fault. */
- if (mm != current->mm && has_swap_token(mm) &&
- rwsem_is_locked(&mm->mmap_sem))
- referenced++;
-
(*mapcount)--;
if (referenced)
+++ /dev/null
-/*
- * 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);
- }
-}
for (priority = DEF_PRIORITY; priority >= 0; priority--) {
sc->nr_scanned = 0;
- if (!priority)
- disable_swap_token(sc->target_mem_cgroup);
aborted_reclaim = shrink_zones(priority, zonelist, sc);
/*
unsigned long lru_pages = 0;
int has_under_min_watermark_zone = 0;
- /* The swap token gets in the way of swapout... */
- if (!priority)
- disable_swap_token(NULL);
-
all_zones_ok = 1;
balanced = 0;