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kernel: Backport MGLRU patch from 6.4
This fixes a bug where the reclaim path could occasionally have long tail latency. Signed-off-by: Kazuki Hashimoto <kazukih0205@gmail.com>
This commit is contained in:
Kazuki Hashimoto
Christian Marangi
parent
b28b8ed1f4
commit
ae8db3941c
@ -0,0 +1,266 @@
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From 087ed25eaf5a78a678508e893f80addab9b1c103 Mon Sep 17 00:00:00 2001
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From: Kalesh Singh <kaleshsingh@google.com>
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Date: Thu, 13 Apr 2023 14:43:26 -0700
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Subject: [PATCH] mm: Multi-gen LRU: remove wait_event_killable()
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Android 14 and later default to MGLRU [1] and field telemetry showed
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occasional long tail latency (>100ms) in the reclaim path.
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Tracing revealed priority inversion in the reclaim path. In
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try_to_inc_max_seq(), when high priority tasks were blocked on
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wait_event_killable(), the preemption of the low priority task to call
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wake_up_all() caused those high priority tasks to wait longer than
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necessary. In general, this problem is not different from others of its
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kind, e.g., one caused by mutex_lock(). However, it is specific to MGLRU
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because it introduced the new wait queue lruvec->mm_state.wait.
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The purpose of this new wait queue is to avoid the thundering herd
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problem. If many direct reclaimers rush into try_to_inc_max_seq(), only
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one can succeed, i.e., the one to wake up the rest, and the rest who
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failed might cause premature OOM kills if they do not wait. So far there
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is no evidence supporting this scenario, based on how often the wait has
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been hit. And this begs the question how useful the wait queue is in
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practice.
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Based on Minchan's recommendation, which is in line with his commit
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6d4675e60135 ("mm: don't be stuck to rmap lock on reclaim path") and the
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rest of the MGLRU code which also uses trylock when possible, remove the
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wait queue.
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[1] https://android-review.googlesource.com/q/I7ed7fbfd6ef9ce10053347528125dd98c39e50bf
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Link: https://lkml.kernel.org/r/20230413214326.2147568-1-kaleshsingh@google.com
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Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks")
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Change-Id: I911f3968fd1adb25171279cc5b6f48ccb7efc8de
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Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
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Suggested-by: Minchan Kim <minchan@kernel.org>
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Reported-by: Wei Wang <wvw@google.com>
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Acked-by: Yu Zhao <yuzhao@google.com>
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Cc: Minchan Kim <minchan@kernel.org>
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Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
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Cc: Oleksandr Natalenko <oleksandr@natalenko.name>
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Cc: Suleiman Souhlal <suleiman@google.com>
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Cc: Suren Baghdasaryan <surenb@google.com>
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Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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---
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include/linux/mmzone.h | 8 +--
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mm/vmscan.c | 111 +++++++++++++++--------------------------
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2 files changed, 42 insertions(+), 77 deletions(-)
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--- a/include/linux/mmzone.h
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+++ b/include/linux/mmzone.h
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@@ -452,18 +452,14 @@ enum {
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struct lru_gen_mm_state {
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/* set to max_seq after each iteration */
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unsigned long seq;
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- /* where the current iteration continues (inclusive) */
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+ /* where the current iteration continues after */
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struct list_head *head;
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- /* where the last iteration ended (exclusive) */
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+ /* where the last iteration ended before */
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struct list_head *tail;
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- /* to wait for the last page table walker to finish */
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- struct wait_queue_head wait;
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/* Bloom filters flip after each iteration */
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unsigned long *filters[NR_BLOOM_FILTERS];
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/* the mm stats for debugging */
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unsigned long stats[NR_HIST_GENS][NR_MM_STATS];
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- /* the number of concurrent page table walkers */
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- int nr_walkers;
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};
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struct lru_gen_mm_walk {
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--- a/mm/vmscan.c
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+++ b/mm/vmscan.c
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@@ -2999,18 +2999,13 @@ void lru_gen_del_mm(struct mm_struct *mm
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if (!lruvec)
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continue;
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- /* where the last iteration ended (exclusive) */
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+ /* where the current iteration continues after */
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+ if (lruvec->mm_state.head == &mm->lru_gen.list)
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+ lruvec->mm_state.head = lruvec->mm_state.head->prev;
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+
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+ /* where the last iteration ended before */
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if (lruvec->mm_state.tail == &mm->lru_gen.list)
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lruvec->mm_state.tail = lruvec->mm_state.tail->next;
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-
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- /* where the current iteration continues (inclusive) */
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- if (lruvec->mm_state.head != &mm->lru_gen.list)
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- continue;
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-
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- lruvec->mm_state.head = lruvec->mm_state.head->next;
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- /* the deletion ends the current iteration */
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- if (lruvec->mm_state.head == &mm_list->fifo)
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- WRITE_ONCE(lruvec->mm_state.seq, lruvec->mm_state.seq + 1);
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}
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list_del_init(&mm->lru_gen.list);
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@@ -3194,68 +3189,54 @@ static bool iterate_mm_list(struct lruve
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struct mm_struct **iter)
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{
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bool first = false;
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- bool last = true;
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+ bool last = false;
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struct mm_struct *mm = NULL;
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struct mem_cgroup *memcg = lruvec_memcg(lruvec);
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struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
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struct lru_gen_mm_state *mm_state = &lruvec->mm_state;
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/*
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- * There are four interesting cases for this page table walker:
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- * 1. It tries to start a new iteration of mm_list with a stale max_seq;
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- * there is nothing left to do.
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- * 2. It's the first of the current generation, and it needs to reset
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- * the Bloom filter for the next generation.
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- * 3. It reaches the end of mm_list, and it needs to increment
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- * mm_state->seq; the iteration is done.
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- * 4. It's the last of the current generation, and it needs to reset the
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- * mm stats counters for the next generation.
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+ * mm_state->seq is incremented after each iteration of mm_list. There
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+ * are three interesting cases for this page table walker:
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+ * 1. It tries to start a new iteration with a stale max_seq: there is
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+ * nothing left to do.
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+ * 2. It started the next iteration: it needs to reset the Bloom filter
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+ * so that a fresh set of PTE tables can be recorded.
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+ * 3. It ended the current iteration: it needs to reset the mm stats
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+ * counters and tell its caller to increment max_seq.
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*/
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spin_lock(&mm_list->lock);
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VM_WARN_ON_ONCE(mm_state->seq + 1 < walk->max_seq);
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- VM_WARN_ON_ONCE(*iter && mm_state->seq > walk->max_seq);
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- VM_WARN_ON_ONCE(*iter && !mm_state->nr_walkers);
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- if (walk->max_seq <= mm_state->seq) {
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- if (!*iter)
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- last = false;
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+ if (walk->max_seq <= mm_state->seq)
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goto done;
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- }
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- if (!mm_state->nr_walkers) {
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- VM_WARN_ON_ONCE(mm_state->head && mm_state->head != &mm_list->fifo);
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+ if (!mm_state->head)
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+ mm_state->head = &mm_list->fifo;
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- mm_state->head = mm_list->fifo.next;
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+ if (mm_state->head == &mm_list->fifo)
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first = true;
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- }
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-
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- while (!mm && mm_state->head != &mm_list->fifo) {
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- mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list);
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+ do {
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mm_state->head = mm_state->head->next;
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+ if (mm_state->head == &mm_list->fifo) {
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+ WRITE_ONCE(mm_state->seq, mm_state->seq + 1);
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+ last = true;
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+ break;
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+ }
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/* force scan for those added after the last iteration */
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- if (!mm_state->tail || mm_state->tail == &mm->lru_gen.list) {
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- mm_state->tail = mm_state->head;
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+ if (!mm_state->tail || mm_state->tail == mm_state->head) {
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+ mm_state->tail = mm_state->head->next;
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walk->force_scan = true;
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}
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+ mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list);
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if (should_skip_mm(mm, walk))
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mm = NULL;
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- }
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-
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- if (mm_state->head == &mm_list->fifo)
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- WRITE_ONCE(mm_state->seq, mm_state->seq + 1);
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+ } while (!mm);
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done:
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- if (*iter && !mm)
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- mm_state->nr_walkers--;
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- if (!*iter && mm)
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- mm_state->nr_walkers++;
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-
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- if (mm_state->nr_walkers)
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- last = false;
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-
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if (*iter || last)
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reset_mm_stats(lruvec, walk, last);
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@@ -3283,9 +3264,9 @@ static bool iterate_mm_list_nowalk(struc
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VM_WARN_ON_ONCE(mm_state->seq + 1 < max_seq);
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- if (max_seq > mm_state->seq && !mm_state->nr_walkers) {
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- VM_WARN_ON_ONCE(mm_state->head && mm_state->head != &mm_list->fifo);
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-
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+ if (max_seq > mm_state->seq) {
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+ mm_state->head = NULL;
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+ mm_state->tail = NULL;
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WRITE_ONCE(mm_state->seq, mm_state->seq + 1);
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reset_mm_stats(lruvec, NULL, true);
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success = true;
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@@ -3894,10 +3875,6 @@ restart:
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walk_pmd_range(&val, addr, next, args);
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- /* a racy check to curtail the waiting time */
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- if (wq_has_sleeper(&walk->lruvec->mm_state.wait))
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- return 1;
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-
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if (need_resched() || walk->batched >= MAX_LRU_BATCH) {
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end = (addr | ~PUD_MASK) + 1;
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goto done;
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@@ -3930,8 +3907,14 @@ static void walk_mm(struct lruvec *lruve
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walk->next_addr = FIRST_USER_ADDRESS;
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do {
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+ DEFINE_MAX_SEQ(lruvec);
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+
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err = -EBUSY;
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+ /* another thread might have called inc_max_seq() */
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+ if (walk->max_seq != max_seq)
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+ break;
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+
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/* page_update_gen() requires stable page_memcg() */
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if (!mem_cgroup_trylock_pages(memcg))
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break;
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@@ -4164,25 +4147,12 @@ static bool try_to_inc_max_seq(struct lr
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success = iterate_mm_list(lruvec, walk, &mm);
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if (mm)
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walk_mm(lruvec, mm, walk);
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-
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- cond_resched();
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} while (mm);
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done:
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- if (!success) {
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- if (sc->priority <= DEF_PRIORITY - 2)
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- wait_event_killable(lruvec->mm_state.wait,
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- max_seq < READ_ONCE(lrugen->max_seq));
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- return false;
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- }
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+ if (success)
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+ inc_max_seq(lruvec, can_swap, force_scan);
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- VM_WARN_ON_ONCE(max_seq != READ_ONCE(lrugen->max_seq));
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-
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- inc_max_seq(lruvec, can_swap, force_scan);
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- /* either this sees any waiters or they will see updated max_seq */
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- if (wq_has_sleeper(&lruvec->mm_state.wait))
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- wake_up_all(&lruvec->mm_state.wait);
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-
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- return true;
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+ return success;
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}
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static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc)
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@@ -5746,7 +5716,6 @@ void lru_gen_init_lruvec(struct lruvec *
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INIT_LIST_HEAD(&lrugen->pages[gen][type][zone]);
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lruvec->mm_state.seq = MIN_NR_GENS;
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- init_waitqueue_head(&lruvec->mm_state.wait);
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}
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#ifdef CONFIG_MEMCG
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@ -0,0 +1,280 @@
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From 418038c22452df38cde519cc8c662bb15139764a Mon Sep 17 00:00:00 2001
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From: Kalesh Singh <kaleshsingh@google.com>
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Date: Thu, 13 Apr 2023 14:43:26 -0700
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Subject: [PATCH 19/19] mm: Multi-gen LRU: remove wait_event_killable()
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|
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Android 14 and later default to MGLRU [1] and field telemetry showed
|
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occasional long tail latency (>100ms) in the reclaim path.
|
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|
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Tracing revealed priority inversion in the reclaim path. In
|
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try_to_inc_max_seq(), when high priority tasks were blocked on
|
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wait_event_killable(), the preemption of the low priority task to call
|
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wake_up_all() caused those high priority tasks to wait longer than
|
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necessary. In general, this problem is not different from others of its
|
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kind, e.g., one caused by mutex_lock(). However, it is specific to MGLRU
|
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because it introduced the new wait queue lruvec->mm_state.wait.
|
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|
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The purpose of this new wait queue is to avoid the thundering herd
|
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problem. If many direct reclaimers rush into try_to_inc_max_seq(), only
|
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one can succeed, i.e., the one to wake up the rest, and the rest who
|
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failed might cause premature OOM kills if they do not wait. So far there
|
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is no evidence supporting this scenario, based on how often the wait has
|
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been hit. And this begs the question how useful the wait queue is in
|
||||
practice.
|
||||
|
||||
Based on Minchan's recommendation, which is in line with his commit
|
||||
6d4675e60135 ("mm: don't be stuck to rmap lock on reclaim path") and the
|
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rest of the MGLRU code which also uses trylock when possible, remove the
|
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wait queue.
|
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|
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[1] https://android-review.googlesource.com/q/I7ed7fbfd6ef9ce10053347528125dd98c39e50bf
|
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|
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Link: https://lkml.kernel.org/r/20230413214326.2147568-1-kaleshsingh@google.com
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Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks")
|
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Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
|
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Suggested-by: Minchan Kim <minchan@kernel.org>
|
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Reported-by: Wei Wang <wvw@google.com>
|
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Acked-by: Yu Zhao <yuzhao@google.com>
|
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Cc: Minchan Kim <minchan@kernel.org>
|
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Cc: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
|
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Cc: Oleksandr Natalenko <oleksandr@natalenko.name>
|
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Cc: Suleiman Souhlal <suleiman@google.com>
|
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Cc: Suren Baghdasaryan <surenb@google.com>
|
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Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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---
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include/linux/mmzone.h | 8 +--
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mm/vmscan.c | 112 +++++++++++++++--------------------------
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2 files changed, 42 insertions(+), 78 deletions(-)
|
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diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
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index 403c7461e7a70..d62a5accf1be4 100644
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--- a/include/linux/mmzone.h
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+++ b/include/linux/mmzone.h
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@@ -453,18 +453,14 @@ enum {
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struct lru_gen_mm_state {
|
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/* set to max_seq after each iteration */
|
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unsigned long seq;
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- /* where the current iteration continues (inclusive) */
|
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+ /* where the current iteration continues after */
|
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struct list_head *head;
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- /* where the last iteration ended (exclusive) */
|
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+ /* where the last iteration ended before */
|
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struct list_head *tail;
|
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- /* to wait for the last page table walker to finish */
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- struct wait_queue_head wait;
|
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/* Bloom filters flip after each iteration */
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unsigned long *filters[NR_BLOOM_FILTERS];
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/* the mm stats for debugging */
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unsigned long stats[NR_HIST_GENS][NR_MM_STATS];
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- /* the number of concurrent page table walkers */
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- int nr_walkers;
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};
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struct lru_gen_mm_walk {
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diff --git a/mm/vmscan.c b/mm/vmscan.c
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index f6ce7a1fd78a3..851758303dbf4 100644
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--- a/mm/vmscan.c
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+++ b/mm/vmscan.c
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@@ -3371,18 +3371,13 @@ void lru_gen_del_mm(struct mm_struct *mm)
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if (!lruvec)
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continue;
|
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- /* where the last iteration ended (exclusive) */
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+ /* where the current iteration continues after */
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+ if (lruvec->mm_state.head == &mm->lru_gen.list)
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+ lruvec->mm_state.head = lruvec->mm_state.head->prev;
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+
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+ /* where the last iteration ended before */
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if (lruvec->mm_state.tail == &mm->lru_gen.list)
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lruvec->mm_state.tail = lruvec->mm_state.tail->next;
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-
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- /* where the current iteration continues (inclusive) */
|
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- if (lruvec->mm_state.head != &mm->lru_gen.list)
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- continue;
|
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-
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- lruvec->mm_state.head = lruvec->mm_state.head->next;
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- /* the deletion ends the current iteration */
|
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- if (lruvec->mm_state.head == &mm_list->fifo)
|
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- WRITE_ONCE(lruvec->mm_state.seq, lruvec->mm_state.seq + 1);
|
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}
|
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|
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list_del_init(&mm->lru_gen.list);
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@@ -3478,68 +3473,54 @@ static bool iterate_mm_list(struct lruvec *lruvec, struct lru_gen_mm_walk *walk,
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struct mm_struct **iter)
|
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{
|
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bool first = false;
|
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- bool last = true;
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+ bool last = false;
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struct mm_struct *mm = NULL;
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struct mem_cgroup *memcg = lruvec_memcg(lruvec);
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struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
|
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struct lru_gen_mm_state *mm_state = &lruvec->mm_state;
|
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|
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/*
|
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- * There are four interesting cases for this page table walker:
|
||||
- * 1. It tries to start a new iteration of mm_list with a stale max_seq;
|
||||
- * there is nothing left to do.
|
||||
- * 2. It's the first of the current generation, and it needs to reset
|
||||
- * the Bloom filter for the next generation.
|
||||
- * 3. It reaches the end of mm_list, and it needs to increment
|
||||
- * mm_state->seq; the iteration is done.
|
||||
- * 4. It's the last of the current generation, and it needs to reset the
|
||||
- * mm stats counters for the next generation.
|
||||
+ * mm_state->seq is incremented after each iteration of mm_list. There
|
||||
+ * are three interesting cases for this page table walker:
|
||||
+ * 1. It tries to start a new iteration with a stale max_seq: there is
|
||||
+ * nothing left to do.
|
||||
+ * 2. It started the next iteration: it needs to reset the Bloom filter
|
||||
+ * so that a fresh set of PTE tables can be recorded.
|
||||
+ * 3. It ended the current iteration: it needs to reset the mm stats
|
||||
+ * counters and tell its caller to increment max_seq.
|
||||
*/
|
||||
spin_lock(&mm_list->lock);
|
||||
|
||||
VM_WARN_ON_ONCE(mm_state->seq + 1 < walk->max_seq);
|
||||
- VM_WARN_ON_ONCE(*iter && mm_state->seq > walk->max_seq);
|
||||
- VM_WARN_ON_ONCE(*iter && !mm_state->nr_walkers);
|
||||
|
||||
- if (walk->max_seq <= mm_state->seq) {
|
||||
- if (!*iter)
|
||||
- last = false;
|
||||
+ if (walk->max_seq <= mm_state->seq)
|
||||
goto done;
|
||||
- }
|
||||
|
||||
- if (!mm_state->nr_walkers) {
|
||||
- VM_WARN_ON_ONCE(mm_state->head && mm_state->head != &mm_list->fifo);
|
||||
+ if (!mm_state->head)
|
||||
+ mm_state->head = &mm_list->fifo;
|
||||
|
||||
- mm_state->head = mm_list->fifo.next;
|
||||
+ if (mm_state->head == &mm_list->fifo)
|
||||
first = true;
|
||||
- }
|
||||
-
|
||||
- while (!mm && mm_state->head != &mm_list->fifo) {
|
||||
- mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list);
|
||||
|
||||
+ do {
|
||||
mm_state->head = mm_state->head->next;
|
||||
+ if (mm_state->head == &mm_list->fifo) {
|
||||
+ WRITE_ONCE(mm_state->seq, mm_state->seq + 1);
|
||||
+ last = true;
|
||||
+ break;
|
||||
+ }
|
||||
|
||||
/* force scan for those added after the last iteration */
|
||||
- if (!mm_state->tail || mm_state->tail == &mm->lru_gen.list) {
|
||||
- mm_state->tail = mm_state->head;
|
||||
+ if (!mm_state->tail || mm_state->tail == mm_state->head) {
|
||||
+ mm_state->tail = mm_state->head->next;
|
||||
walk->force_scan = true;
|
||||
}
|
||||
|
||||
+ mm = list_entry(mm_state->head, struct mm_struct, lru_gen.list);
|
||||
if (should_skip_mm(mm, walk))
|
||||
mm = NULL;
|
||||
- }
|
||||
-
|
||||
- if (mm_state->head == &mm_list->fifo)
|
||||
- WRITE_ONCE(mm_state->seq, mm_state->seq + 1);
|
||||
+ } while (!mm);
|
||||
done:
|
||||
- if (*iter && !mm)
|
||||
- mm_state->nr_walkers--;
|
||||
- if (!*iter && mm)
|
||||
- mm_state->nr_walkers++;
|
||||
-
|
||||
- if (mm_state->nr_walkers)
|
||||
- last = false;
|
||||
-
|
||||
if (*iter || last)
|
||||
reset_mm_stats(lruvec, walk, last);
|
||||
|
||||
@@ -3567,9 +3548,9 @@ static bool iterate_mm_list_nowalk(struct lruvec *lruvec, unsigned long max_seq)
|
||||
|
||||
VM_WARN_ON_ONCE(mm_state->seq + 1 < max_seq);
|
||||
|
||||
- if (max_seq > mm_state->seq && !mm_state->nr_walkers) {
|
||||
- VM_WARN_ON_ONCE(mm_state->head && mm_state->head != &mm_list->fifo);
|
||||
-
|
||||
+ if (max_seq > mm_state->seq) {
|
||||
+ mm_state->head = NULL;
|
||||
+ mm_state->tail = NULL;
|
||||
WRITE_ONCE(mm_state->seq, mm_state->seq + 1);
|
||||
reset_mm_stats(lruvec, NULL, true);
|
||||
success = true;
|
||||
@@ -4172,10 +4153,6 @@ static int walk_pud_range(p4d_t *p4d, unsigned long start, unsigned long end,
|
||||
|
||||
walk_pmd_range(&val, addr, next, args);
|
||||
|
||||
- /* a racy check to curtail the waiting time */
|
||||
- if (wq_has_sleeper(&walk->lruvec->mm_state.wait))
|
||||
- return 1;
|
||||
-
|
||||
if (need_resched() || walk->batched >= MAX_LRU_BATCH) {
|
||||
end = (addr | ~PUD_MASK) + 1;
|
||||
goto done;
|
||||
@@ -4208,8 +4185,14 @@ static void walk_mm(struct lruvec *lruvec, struct mm_struct *mm, struct lru_gen_
|
||||
walk->next_addr = FIRST_USER_ADDRESS;
|
||||
|
||||
do {
|
||||
+ DEFINE_MAX_SEQ(lruvec);
|
||||
+
|
||||
err = -EBUSY;
|
||||
|
||||
+ /* another thread might have called inc_max_seq() */
|
||||
+ if (walk->max_seq != max_seq)
|
||||
+ break;
|
||||
+
|
||||
/* folio_update_gen() requires stable folio_memcg() */
|
||||
if (!mem_cgroup_trylock_pages(memcg))
|
||||
break;
|
||||
@@ -4442,25 +4425,12 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq,
|
||||
success = iterate_mm_list(lruvec, walk, &mm);
|
||||
if (mm)
|
||||
walk_mm(lruvec, mm, walk);
|
||||
-
|
||||
- cond_resched();
|
||||
} while (mm);
|
||||
done:
|
||||
- if (!success) {
|
||||
- if (sc->priority <= DEF_PRIORITY - 2)
|
||||
- wait_event_killable(lruvec->mm_state.wait,
|
||||
- max_seq < READ_ONCE(lrugen->max_seq));
|
||||
- return false;
|
||||
- }
|
||||
+ if (success)
|
||||
+ inc_max_seq(lruvec, can_swap, force_scan);
|
||||
|
||||
- VM_WARN_ON_ONCE(max_seq != READ_ONCE(lrugen->max_seq));
|
||||
-
|
||||
- inc_max_seq(lruvec, can_swap, force_scan);
|
||||
- /* either this sees any waiters or they will see updated max_seq */
|
||||
- if (wq_has_sleeper(&lruvec->mm_state.wait))
|
||||
- wake_up_all(&lruvec->mm_state.wait);
|
||||
-
|
||||
- return true;
|
||||
+ return success;
|
||||
}
|
||||
|
||||
/******************************************************************************
|
||||
@@ -6105,7 +6075,6 @@ void lru_gen_init_lruvec(struct lruvec *lruvec)
|
||||
INIT_LIST_HEAD(&lrugen->folios[gen][type][zone]);
|
||||
|
||||
lruvec->mm_state.seq = MIN_NR_GENS;
|
||||
- init_waitqueue_head(&lruvec->mm_state.wait);
|
||||
}
|
||||
|
||||
#ifdef CONFIG_MEMCG
|
||||
@@ -6138,7 +6107,6 @@ void lru_gen_exit_memcg(struct mem_cgroup *memcg)
|
||||
for_each_node(nid) {
|
||||
struct lruvec *lruvec = get_lruvec(memcg, nid);
|
||||
|
||||
- VM_WARN_ON_ONCE(lruvec->mm_state.nr_walkers);
|
||||
VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0,
|
||||
sizeof(lruvec->lrugen.nr_pages)));
|
||||
|
||||
--
|
||||
2.40.1
|
||||
|
||||
Loading…
Reference in New Issue
Block a user