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c68ed79457
Disable preemption on -RT for the vmstat code. On vanila the code runs in IRQ-off regions while on -RT it may not when stats are updated under a local_lock. "preempt_disable" ensures that the same resources is not updated in parallel due to preemption. This patch differs from the preempt-rt version where __count_vm_event and __count_vm_events are also protected. The counters are explicitly "allowed to be to be racy" so there is no need to protect them from preemption. Only the accurate page stats that are updated by a read-modify-write need protection. This patch also differs in that a preempt_[en|dis]able_rt helper is not used. As vmstat is the only user of the helper, it was suggested that it be open-coded in vmstat.c instead of risking the helper being used in unnecessary contexts. Link: https://lkml.kernel.org/r/20210805160019.1137-2-mgorman@techsingularity.net Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2226 lines
54 KiB
C
2226 lines
54 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* linux/mm/vmstat.c
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*
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* Manages VM statistics
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* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
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*
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* zoned VM statistics
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* Copyright (C) 2006 Silicon Graphics, Inc.,
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* Christoph Lameter <christoph@lameter.com>
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* Copyright (C) 2008-2014 Christoph Lameter
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*/
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#include <linux/fs.h>
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#include <linux/mm.h>
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#include <linux/err.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/cpu.h>
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#include <linux/cpumask.h>
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#include <linux/vmstat.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/debugfs.h>
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#include <linux/sched.h>
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#include <linux/math64.h>
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#include <linux/writeback.h>
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#include <linux/compaction.h>
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#include <linux/mm_inline.h>
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#include <linux/page_ext.h>
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#include <linux/page_owner.h>
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#include "internal.h"
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#ifdef CONFIG_NUMA
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int sysctl_vm_numa_stat = ENABLE_NUMA_STAT;
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/* zero numa counters within a zone */
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static void zero_zone_numa_counters(struct zone *zone)
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{
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int item, cpu;
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for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++) {
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atomic_long_set(&zone->vm_numa_event[item], 0);
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for_each_online_cpu(cpu) {
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per_cpu_ptr(zone->per_cpu_zonestats, cpu)->vm_numa_event[item]
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= 0;
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}
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}
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}
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/* zero numa counters of all the populated zones */
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static void zero_zones_numa_counters(void)
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{
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struct zone *zone;
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for_each_populated_zone(zone)
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zero_zone_numa_counters(zone);
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}
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/* zero global numa counters */
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static void zero_global_numa_counters(void)
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{
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int item;
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for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++)
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atomic_long_set(&vm_numa_event[item], 0);
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}
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static void invalid_numa_statistics(void)
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{
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zero_zones_numa_counters();
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zero_global_numa_counters();
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}
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static DEFINE_MUTEX(vm_numa_stat_lock);
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int sysctl_vm_numa_stat_handler(struct ctl_table *table, int write,
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void *buffer, size_t *length, loff_t *ppos)
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{
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int ret, oldval;
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mutex_lock(&vm_numa_stat_lock);
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if (write)
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oldval = sysctl_vm_numa_stat;
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ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
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if (ret || !write)
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goto out;
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if (oldval == sysctl_vm_numa_stat)
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goto out;
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else if (sysctl_vm_numa_stat == ENABLE_NUMA_STAT) {
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static_branch_enable(&vm_numa_stat_key);
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pr_info("enable numa statistics\n");
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} else {
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static_branch_disable(&vm_numa_stat_key);
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invalid_numa_statistics();
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pr_info("disable numa statistics, and clear numa counters\n");
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}
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out:
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mutex_unlock(&vm_numa_stat_lock);
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return ret;
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}
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#endif
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#ifdef CONFIG_VM_EVENT_COUNTERS
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DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
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EXPORT_PER_CPU_SYMBOL(vm_event_states);
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static void sum_vm_events(unsigned long *ret)
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{
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int cpu;
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int i;
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memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
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for_each_online_cpu(cpu) {
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struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
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for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
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ret[i] += this->event[i];
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}
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}
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/*
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* Accumulate the vm event counters across all CPUs.
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* The result is unavoidably approximate - it can change
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* during and after execution of this function.
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*/
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void all_vm_events(unsigned long *ret)
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{
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cpus_read_lock();
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sum_vm_events(ret);
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cpus_read_unlock();
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}
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EXPORT_SYMBOL_GPL(all_vm_events);
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/*
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* Fold the foreign cpu events into our own.
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*
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* This is adding to the events on one processor
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* but keeps the global counts constant.
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*/
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void vm_events_fold_cpu(int cpu)
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{
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struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
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int i;
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for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
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count_vm_events(i, fold_state->event[i]);
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fold_state->event[i] = 0;
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}
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}
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#endif /* CONFIG_VM_EVENT_COUNTERS */
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/*
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* Manage combined zone based / global counters
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*
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* vm_stat contains the global counters
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*/
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atomic_long_t vm_zone_stat[NR_VM_ZONE_STAT_ITEMS] __cacheline_aligned_in_smp;
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atomic_long_t vm_node_stat[NR_VM_NODE_STAT_ITEMS] __cacheline_aligned_in_smp;
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atomic_long_t vm_numa_event[NR_VM_NUMA_EVENT_ITEMS] __cacheline_aligned_in_smp;
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EXPORT_SYMBOL(vm_zone_stat);
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EXPORT_SYMBOL(vm_node_stat);
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#ifdef CONFIG_SMP
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int calculate_pressure_threshold(struct zone *zone)
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{
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int threshold;
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int watermark_distance;
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/*
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* As vmstats are not up to date, there is drift between the estimated
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* and real values. For high thresholds and a high number of CPUs, it
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* is possible for the min watermark to be breached while the estimated
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* value looks fine. The pressure threshold is a reduced value such
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* that even the maximum amount of drift will not accidentally breach
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* the min watermark
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*/
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watermark_distance = low_wmark_pages(zone) - min_wmark_pages(zone);
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threshold = max(1, (int)(watermark_distance / num_online_cpus()));
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/*
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* Maximum threshold is 125
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*/
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threshold = min(125, threshold);
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return threshold;
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}
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int calculate_normal_threshold(struct zone *zone)
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{
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int threshold;
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int mem; /* memory in 128 MB units */
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/*
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* The threshold scales with the number of processors and the amount
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* of memory per zone. More memory means that we can defer updates for
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* longer, more processors could lead to more contention.
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* fls() is used to have a cheap way of logarithmic scaling.
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*
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* Some sample thresholds:
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*
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* Threshold Processors (fls) Zonesize fls(mem)+1
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* ------------------------------------------------------------------
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* 8 1 1 0.9-1 GB 4
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* 16 2 2 0.9-1 GB 4
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* 20 2 2 1-2 GB 5
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* 24 2 2 2-4 GB 6
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* 28 2 2 4-8 GB 7
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* 32 2 2 8-16 GB 8
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* 4 2 2 <128M 1
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* 30 4 3 2-4 GB 5
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* 48 4 3 8-16 GB 8
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* 32 8 4 1-2 GB 4
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* 32 8 4 0.9-1GB 4
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* 10 16 5 <128M 1
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* 40 16 5 900M 4
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* 70 64 7 2-4 GB 5
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* 84 64 7 4-8 GB 6
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* 108 512 9 4-8 GB 6
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* 125 1024 10 8-16 GB 8
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* 125 1024 10 16-32 GB 9
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*/
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mem = zone_managed_pages(zone) >> (27 - PAGE_SHIFT);
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threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
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/*
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* Maximum threshold is 125
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*/
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threshold = min(125, threshold);
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return threshold;
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}
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/*
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* Refresh the thresholds for each zone.
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*/
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void refresh_zone_stat_thresholds(void)
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{
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struct pglist_data *pgdat;
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struct zone *zone;
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int cpu;
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int threshold;
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/* Zero current pgdat thresholds */
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for_each_online_pgdat(pgdat) {
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for_each_online_cpu(cpu) {
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per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold = 0;
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}
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}
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for_each_populated_zone(zone) {
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struct pglist_data *pgdat = zone->zone_pgdat;
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unsigned long max_drift, tolerate_drift;
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threshold = calculate_normal_threshold(zone);
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for_each_online_cpu(cpu) {
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int pgdat_threshold;
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per_cpu_ptr(zone->per_cpu_zonestats, cpu)->stat_threshold
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= threshold;
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/* Base nodestat threshold on the largest populated zone. */
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pgdat_threshold = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold;
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per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold
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= max(threshold, pgdat_threshold);
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}
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/*
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* Only set percpu_drift_mark if there is a danger that
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* NR_FREE_PAGES reports the low watermark is ok when in fact
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* the min watermark could be breached by an allocation
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*/
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tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone);
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max_drift = num_online_cpus() * threshold;
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if (max_drift > tolerate_drift)
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zone->percpu_drift_mark = high_wmark_pages(zone) +
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max_drift;
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}
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}
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void set_pgdat_percpu_threshold(pg_data_t *pgdat,
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int (*calculate_pressure)(struct zone *))
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{
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struct zone *zone;
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int cpu;
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int threshold;
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int i;
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for (i = 0; i < pgdat->nr_zones; i++) {
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zone = &pgdat->node_zones[i];
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if (!zone->percpu_drift_mark)
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continue;
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threshold = (*calculate_pressure)(zone);
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for_each_online_cpu(cpu)
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per_cpu_ptr(zone->per_cpu_zonestats, cpu)->stat_threshold
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= threshold;
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}
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}
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/*
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* For use when we know that interrupts are disabled,
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* or when we know that preemption is disabled and that
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* particular counter cannot be updated from interrupt context.
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*/
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void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
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long delta)
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{
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struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
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s8 __percpu *p = pcp->vm_stat_diff + item;
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long x;
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long t;
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/*
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* Accurate vmstat updates require a RMW. On !PREEMPT_RT kernels,
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* atomicity is provided by IRQs being disabled -- either explicitly
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* or via local_lock_irq. On PREEMPT_RT, local_lock_irq only disables
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* CPU migrations and preemption potentially corrupts a counter so
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* disable preemption.
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*/
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_disable();
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x = delta + __this_cpu_read(*p);
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t = __this_cpu_read(pcp->stat_threshold);
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if (unlikely(abs(x) > t)) {
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zone_page_state_add(x, zone, item);
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x = 0;
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}
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__this_cpu_write(*p, x);
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_enable();
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}
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EXPORT_SYMBOL(__mod_zone_page_state);
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void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
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long delta)
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{
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struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
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s8 __percpu *p = pcp->vm_node_stat_diff + item;
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long x;
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long t;
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if (vmstat_item_in_bytes(item)) {
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/*
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* Only cgroups use subpage accounting right now; at
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* the global level, these items still change in
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* multiples of whole pages. Store them as pages
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* internally to keep the per-cpu counters compact.
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*/
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VM_WARN_ON_ONCE(delta & (PAGE_SIZE - 1));
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delta >>= PAGE_SHIFT;
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}
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/* See __mod_node_page_state */
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_disable();
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x = delta + __this_cpu_read(*p);
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t = __this_cpu_read(pcp->stat_threshold);
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if (unlikely(abs(x) > t)) {
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node_page_state_add(x, pgdat, item);
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x = 0;
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}
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__this_cpu_write(*p, x);
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_enable();
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}
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EXPORT_SYMBOL(__mod_node_page_state);
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/*
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* Optimized increment and decrement functions.
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*
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* These are only for a single page and therefore can take a struct page *
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* argument instead of struct zone *. This allows the inclusion of the code
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* generated for page_zone(page) into the optimized functions.
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*
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* No overflow check is necessary and therefore the differential can be
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* incremented or decremented in place which may allow the compilers to
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* generate better code.
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* The increment or decrement is known and therefore one boundary check can
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* be omitted.
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*
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* NOTE: These functions are very performance sensitive. Change only
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* with care.
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*
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* Some processors have inc/dec instructions that are atomic vs an interrupt.
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* However, the code must first determine the differential location in a zone
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* based on the processor number and then inc/dec the counter. There is no
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* guarantee without disabling preemption that the processor will not change
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* in between and therefore the atomicity vs. interrupt cannot be exploited
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* in a useful way here.
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*/
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void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
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{
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struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
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s8 __percpu *p = pcp->vm_stat_diff + item;
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s8 v, t;
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/* See __mod_node_page_state */
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_disable();
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v = __this_cpu_inc_return(*p);
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t = __this_cpu_read(pcp->stat_threshold);
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if (unlikely(v > t)) {
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s8 overstep = t >> 1;
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zone_page_state_add(v + overstep, zone, item);
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__this_cpu_write(*p, -overstep);
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}
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_enable();
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}
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void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
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{
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struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
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s8 __percpu *p = pcp->vm_node_stat_diff + item;
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s8 v, t;
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VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
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/* See __mod_node_page_state */
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_disable();
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v = __this_cpu_inc_return(*p);
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t = __this_cpu_read(pcp->stat_threshold);
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if (unlikely(v > t)) {
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s8 overstep = t >> 1;
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node_page_state_add(v + overstep, pgdat, item);
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__this_cpu_write(*p, -overstep);
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}
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_enable();
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}
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void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
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{
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__inc_zone_state(page_zone(page), item);
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}
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EXPORT_SYMBOL(__inc_zone_page_state);
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void __inc_node_page_state(struct page *page, enum node_stat_item item)
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{
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__inc_node_state(page_pgdat(page), item);
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}
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EXPORT_SYMBOL(__inc_node_page_state);
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void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
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{
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struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
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s8 __percpu *p = pcp->vm_stat_diff + item;
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s8 v, t;
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/* See __mod_node_page_state */
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_disable();
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v = __this_cpu_dec_return(*p);
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t = __this_cpu_read(pcp->stat_threshold);
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if (unlikely(v < - t)) {
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s8 overstep = t >> 1;
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zone_page_state_add(v - overstep, zone, item);
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__this_cpu_write(*p, overstep);
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}
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if (IS_ENABLED(CONFIG_PREEMPT_RT))
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preempt_enable();
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}
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|
|
void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
|
|
{
|
|
struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
|
|
s8 __percpu *p = pcp->vm_node_stat_diff + item;
|
|
s8 v, t;
|
|
|
|
VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
|
|
|
|
/* See __mod_node_page_state */
|
|
if (IS_ENABLED(CONFIG_PREEMPT_RT))
|
|
preempt_disable();
|
|
|
|
v = __this_cpu_dec_return(*p);
|
|
t = __this_cpu_read(pcp->stat_threshold);
|
|
if (unlikely(v < - t)) {
|
|
s8 overstep = t >> 1;
|
|
|
|
node_page_state_add(v - overstep, pgdat, item);
|
|
__this_cpu_write(*p, overstep);
|
|
}
|
|
|
|
if (IS_ENABLED(CONFIG_PREEMPT_RT))
|
|
preempt_enable();
|
|
}
|
|
|
|
void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
|
|
{
|
|
__dec_zone_state(page_zone(page), item);
|
|
}
|
|
EXPORT_SYMBOL(__dec_zone_page_state);
|
|
|
|
void __dec_node_page_state(struct page *page, enum node_stat_item item)
|
|
{
|
|
__dec_node_state(page_pgdat(page), item);
|
|
}
|
|
EXPORT_SYMBOL(__dec_node_page_state);
|
|
|
|
#ifdef CONFIG_HAVE_CMPXCHG_LOCAL
|
|
/*
|
|
* If we have cmpxchg_local support then we do not need to incur the overhead
|
|
* that comes with local_irq_save/restore if we use this_cpu_cmpxchg.
|
|
*
|
|
* mod_state() modifies the zone counter state through atomic per cpu
|
|
* operations.
|
|
*
|
|
* Overstep mode specifies how overstep should handled:
|
|
* 0 No overstepping
|
|
* 1 Overstepping half of threshold
|
|
* -1 Overstepping minus half of threshold
|
|
*/
|
|
static inline void mod_zone_state(struct zone *zone,
|
|
enum zone_stat_item item, long delta, int overstep_mode)
|
|
{
|
|
struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats;
|
|
s8 __percpu *p = pcp->vm_stat_diff + item;
|
|
long o, n, t, z;
|
|
|
|
do {
|
|
z = 0; /* overflow to zone counters */
|
|
|
|
/*
|
|
* The fetching of the stat_threshold is racy. We may apply
|
|
* a counter threshold to the wrong the cpu if we get
|
|
* rescheduled while executing here. However, the next
|
|
* counter update will apply the threshold again and
|
|
* therefore bring the counter under the threshold again.
|
|
*
|
|
* Most of the time the thresholds are the same anyways
|
|
* for all cpus in a zone.
|
|
*/
|
|
t = this_cpu_read(pcp->stat_threshold);
|
|
|
|
o = this_cpu_read(*p);
|
|
n = delta + o;
|
|
|
|
if (abs(n) > t) {
|
|
int os = overstep_mode * (t >> 1) ;
|
|
|
|
/* Overflow must be added to zone counters */
|
|
z = n + os;
|
|
n = -os;
|
|
}
|
|
} while (this_cpu_cmpxchg(*p, o, n) != o);
|
|
|
|
if (z)
|
|
zone_page_state_add(z, zone, item);
|
|
}
|
|
|
|
void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
|
|
long delta)
|
|
{
|
|
mod_zone_state(zone, item, delta, 0);
|
|
}
|
|
EXPORT_SYMBOL(mod_zone_page_state);
|
|
|
|
void inc_zone_page_state(struct page *page, enum zone_stat_item item)
|
|
{
|
|
mod_zone_state(page_zone(page), item, 1, 1);
|
|
}
|
|
EXPORT_SYMBOL(inc_zone_page_state);
|
|
|
|
void dec_zone_page_state(struct page *page, enum zone_stat_item item)
|
|
{
|
|
mod_zone_state(page_zone(page), item, -1, -1);
|
|
}
|
|
EXPORT_SYMBOL(dec_zone_page_state);
|
|
|
|
static inline void mod_node_state(struct pglist_data *pgdat,
|
|
enum node_stat_item item, int delta, int overstep_mode)
|
|
{
|
|
struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
|
|
s8 __percpu *p = pcp->vm_node_stat_diff + item;
|
|
long o, n, t, z;
|
|
|
|
if (vmstat_item_in_bytes(item)) {
|
|
/*
|
|
* Only cgroups use subpage accounting right now; at
|
|
* the global level, these items still change in
|
|
* multiples of whole pages. Store them as pages
|
|
* internally to keep the per-cpu counters compact.
|
|
*/
|
|
VM_WARN_ON_ONCE(delta & (PAGE_SIZE - 1));
|
|
delta >>= PAGE_SHIFT;
|
|
}
|
|
|
|
do {
|
|
z = 0; /* overflow to node counters */
|
|
|
|
/*
|
|
* The fetching of the stat_threshold is racy. We may apply
|
|
* a counter threshold to the wrong the cpu if we get
|
|
* rescheduled while executing here. However, the next
|
|
* counter update will apply the threshold again and
|
|
* therefore bring the counter under the threshold again.
|
|
*
|
|
* Most of the time the thresholds are the same anyways
|
|
* for all cpus in a node.
|
|
*/
|
|
t = this_cpu_read(pcp->stat_threshold);
|
|
|
|
o = this_cpu_read(*p);
|
|
n = delta + o;
|
|
|
|
if (abs(n) > t) {
|
|
int os = overstep_mode * (t >> 1) ;
|
|
|
|
/* Overflow must be added to node counters */
|
|
z = n + os;
|
|
n = -os;
|
|
}
|
|
} while (this_cpu_cmpxchg(*p, o, n) != o);
|
|
|
|
if (z)
|
|
node_page_state_add(z, pgdat, item);
|
|
}
|
|
|
|
void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
|
|
long delta)
|
|
{
|
|
mod_node_state(pgdat, item, delta, 0);
|
|
}
|
|
EXPORT_SYMBOL(mod_node_page_state);
|
|
|
|
void inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
|
|
{
|
|
mod_node_state(pgdat, item, 1, 1);
|
|
}
|
|
|
|
void inc_node_page_state(struct page *page, enum node_stat_item item)
|
|
{
|
|
mod_node_state(page_pgdat(page), item, 1, 1);
|
|
}
|
|
EXPORT_SYMBOL(inc_node_page_state);
|
|
|
|
void dec_node_page_state(struct page *page, enum node_stat_item item)
|
|
{
|
|
mod_node_state(page_pgdat(page), item, -1, -1);
|
|
}
|
|
EXPORT_SYMBOL(dec_node_page_state);
|
|
#else
|
|
/*
|
|
* Use interrupt disable to serialize counter updates
|
|
*/
|
|
void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
|
|
long delta)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__mod_zone_page_state(zone, item, delta);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(mod_zone_page_state);
|
|
|
|
void inc_zone_page_state(struct page *page, enum zone_stat_item item)
|
|
{
|
|
unsigned long flags;
|
|
struct zone *zone;
|
|
|
|
zone = page_zone(page);
|
|
local_irq_save(flags);
|
|
__inc_zone_state(zone, item);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(inc_zone_page_state);
|
|
|
|
void dec_zone_page_state(struct page *page, enum zone_stat_item item)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__dec_zone_page_state(page, item);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(dec_zone_page_state);
|
|
|
|
void inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__inc_node_state(pgdat, item);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(inc_node_state);
|
|
|
|
void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
|
|
long delta)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__mod_node_page_state(pgdat, item, delta);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(mod_node_page_state);
|
|
|
|
void inc_node_page_state(struct page *page, enum node_stat_item item)
|
|
{
|
|
unsigned long flags;
|
|
struct pglist_data *pgdat;
|
|
|
|
pgdat = page_pgdat(page);
|
|
local_irq_save(flags);
|
|
__inc_node_state(pgdat, item);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(inc_node_page_state);
|
|
|
|
void dec_node_page_state(struct page *page, enum node_stat_item item)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__dec_node_page_state(page, item);
|
|
local_irq_restore(flags);
|
|
}
|
|
EXPORT_SYMBOL(dec_node_page_state);
|
|
#endif
|
|
|
|
/*
|
|
* Fold a differential into the global counters.
|
|
* Returns the number of counters updated.
|
|
*/
|
|
static int fold_diff(int *zone_diff, int *node_diff)
|
|
{
|
|
int i;
|
|
int changes = 0;
|
|
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
|
|
if (zone_diff[i]) {
|
|
atomic_long_add(zone_diff[i], &vm_zone_stat[i]);
|
|
changes++;
|
|
}
|
|
|
|
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
|
|
if (node_diff[i]) {
|
|
atomic_long_add(node_diff[i], &vm_node_stat[i]);
|
|
changes++;
|
|
}
|
|
return changes;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
static void fold_vm_zone_numa_events(struct zone *zone)
|
|
{
|
|
unsigned long zone_numa_events[NR_VM_NUMA_EVENT_ITEMS] = { 0, };
|
|
int cpu;
|
|
enum numa_stat_item item;
|
|
|
|
for_each_online_cpu(cpu) {
|
|
struct per_cpu_zonestat *pzstats;
|
|
|
|
pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
|
|
for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++)
|
|
zone_numa_events[item] += xchg(&pzstats->vm_numa_event[item], 0);
|
|
}
|
|
|
|
for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++)
|
|
zone_numa_event_add(zone_numa_events[item], zone, item);
|
|
}
|
|
|
|
void fold_vm_numa_events(void)
|
|
{
|
|
struct zone *zone;
|
|
|
|
for_each_populated_zone(zone)
|
|
fold_vm_zone_numa_events(zone);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Update the zone counters for the current cpu.
|
|
*
|
|
* Note that refresh_cpu_vm_stats strives to only access
|
|
* node local memory. The per cpu pagesets on remote zones are placed
|
|
* in the memory local to the processor using that pageset. So the
|
|
* loop over all zones will access a series of cachelines local to
|
|
* the processor.
|
|
*
|
|
* The call to zone_page_state_add updates the cachelines with the
|
|
* statistics in the remote zone struct as well as the global cachelines
|
|
* with the global counters. These could cause remote node cache line
|
|
* bouncing and will have to be only done when necessary.
|
|
*
|
|
* The function returns the number of global counters updated.
|
|
*/
|
|
static int refresh_cpu_vm_stats(bool do_pagesets)
|
|
{
|
|
struct pglist_data *pgdat;
|
|
struct zone *zone;
|
|
int i;
|
|
int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
|
|
int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
|
|
int changes = 0;
|
|
|
|
for_each_populated_zone(zone) {
|
|
struct per_cpu_zonestat __percpu *pzstats = zone->per_cpu_zonestats;
|
|
#ifdef CONFIG_NUMA
|
|
struct per_cpu_pages __percpu *pcp = zone->per_cpu_pageset;
|
|
#endif
|
|
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
|
|
int v;
|
|
|
|
v = this_cpu_xchg(pzstats->vm_stat_diff[i], 0);
|
|
if (v) {
|
|
|
|
atomic_long_add(v, &zone->vm_stat[i]);
|
|
global_zone_diff[i] += v;
|
|
#ifdef CONFIG_NUMA
|
|
/* 3 seconds idle till flush */
|
|
__this_cpu_write(pcp->expire, 3);
|
|
#endif
|
|
}
|
|
}
|
|
#ifdef CONFIG_NUMA
|
|
|
|
if (do_pagesets) {
|
|
cond_resched();
|
|
/*
|
|
* Deal with draining the remote pageset of this
|
|
* processor
|
|
*
|
|
* Check if there are pages remaining in this pageset
|
|
* if not then there is nothing to expire.
|
|
*/
|
|
if (!__this_cpu_read(pcp->expire) ||
|
|
!__this_cpu_read(pcp->count))
|
|
continue;
|
|
|
|
/*
|
|
* We never drain zones local to this processor.
|
|
*/
|
|
if (zone_to_nid(zone) == numa_node_id()) {
|
|
__this_cpu_write(pcp->expire, 0);
|
|
continue;
|
|
}
|
|
|
|
if (__this_cpu_dec_return(pcp->expire))
|
|
continue;
|
|
|
|
if (__this_cpu_read(pcp->count)) {
|
|
drain_zone_pages(zone, this_cpu_ptr(pcp));
|
|
changes++;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
struct per_cpu_nodestat __percpu *p = pgdat->per_cpu_nodestats;
|
|
|
|
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
|
|
int v;
|
|
|
|
v = this_cpu_xchg(p->vm_node_stat_diff[i], 0);
|
|
if (v) {
|
|
atomic_long_add(v, &pgdat->vm_stat[i]);
|
|
global_node_diff[i] += v;
|
|
}
|
|
}
|
|
}
|
|
|
|
changes += fold_diff(global_zone_diff, global_node_diff);
|
|
return changes;
|
|
}
|
|
|
|
/*
|
|
* Fold the data for an offline cpu into the global array.
|
|
* There cannot be any access by the offline cpu and therefore
|
|
* synchronization is simplified.
|
|
*/
|
|
void cpu_vm_stats_fold(int cpu)
|
|
{
|
|
struct pglist_data *pgdat;
|
|
struct zone *zone;
|
|
int i;
|
|
int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
|
|
int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
|
|
|
|
for_each_populated_zone(zone) {
|
|
struct per_cpu_zonestat *pzstats;
|
|
|
|
pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
|
|
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
|
|
if (pzstats->vm_stat_diff[i]) {
|
|
int v;
|
|
|
|
v = pzstats->vm_stat_diff[i];
|
|
pzstats->vm_stat_diff[i] = 0;
|
|
atomic_long_add(v, &zone->vm_stat[i]);
|
|
global_zone_diff[i] += v;
|
|
}
|
|
}
|
|
#ifdef CONFIG_NUMA
|
|
for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) {
|
|
if (pzstats->vm_numa_event[i]) {
|
|
unsigned long v;
|
|
|
|
v = pzstats->vm_numa_event[i];
|
|
pzstats->vm_numa_event[i] = 0;
|
|
zone_numa_event_add(v, zone, i);
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
for_each_online_pgdat(pgdat) {
|
|
struct per_cpu_nodestat *p;
|
|
|
|
p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu);
|
|
|
|
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
|
|
if (p->vm_node_stat_diff[i]) {
|
|
int v;
|
|
|
|
v = p->vm_node_stat_diff[i];
|
|
p->vm_node_stat_diff[i] = 0;
|
|
atomic_long_add(v, &pgdat->vm_stat[i]);
|
|
global_node_diff[i] += v;
|
|
}
|
|
}
|
|
|
|
fold_diff(global_zone_diff, global_node_diff);
|
|
}
|
|
|
|
/*
|
|
* this is only called if !populated_zone(zone), which implies no other users of
|
|
* pset->vm_stat_diff[] exist.
|
|
*/
|
|
void drain_zonestat(struct zone *zone, struct per_cpu_zonestat *pzstats)
|
|
{
|
|
unsigned long v;
|
|
int i;
|
|
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
|
|
if (pzstats->vm_stat_diff[i]) {
|
|
v = pzstats->vm_stat_diff[i];
|
|
pzstats->vm_stat_diff[i] = 0;
|
|
zone_page_state_add(v, zone, i);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) {
|
|
if (pzstats->vm_numa_event[i]) {
|
|
v = pzstats->vm_numa_event[i];
|
|
pzstats->vm_numa_event[i] = 0;
|
|
zone_numa_event_add(v, zone, i);
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* Determine the per node value of a stat item. This function
|
|
* is called frequently in a NUMA machine, so try to be as
|
|
* frugal as possible.
|
|
*/
|
|
unsigned long sum_zone_node_page_state(int node,
|
|
enum zone_stat_item item)
|
|
{
|
|
struct zone *zones = NODE_DATA(node)->node_zones;
|
|
int i;
|
|
unsigned long count = 0;
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++)
|
|
count += zone_page_state(zones + i, item);
|
|
|
|
return count;
|
|
}
|
|
|
|
/* Determine the per node value of a numa stat item. */
|
|
unsigned long sum_zone_numa_event_state(int node,
|
|
enum numa_stat_item item)
|
|
{
|
|
struct zone *zones = NODE_DATA(node)->node_zones;
|
|
unsigned long count = 0;
|
|
int i;
|
|
|
|
for (i = 0; i < MAX_NR_ZONES; i++)
|
|
count += zone_numa_event_state(zones + i, item);
|
|
|
|
return count;
|
|
}
|
|
|
|
/*
|
|
* Determine the per node value of a stat item.
|
|
*/
|
|
unsigned long node_page_state_pages(struct pglist_data *pgdat,
|
|
enum node_stat_item item)
|
|
{
|
|
long x = atomic_long_read(&pgdat->vm_stat[item]);
|
|
#ifdef CONFIG_SMP
|
|
if (x < 0)
|
|
x = 0;
|
|
#endif
|
|
return x;
|
|
}
|
|
|
|
unsigned long node_page_state(struct pglist_data *pgdat,
|
|
enum node_stat_item item)
|
|
{
|
|
VM_WARN_ON_ONCE(vmstat_item_in_bytes(item));
|
|
|
|
return node_page_state_pages(pgdat, item);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_COMPACTION
|
|
|
|
struct contig_page_info {
|
|
unsigned long free_pages;
|
|
unsigned long free_blocks_total;
|
|
unsigned long free_blocks_suitable;
|
|
};
|
|
|
|
/*
|
|
* Calculate the number of free pages in a zone, how many contiguous
|
|
* pages are free and how many are large enough to satisfy an allocation of
|
|
* the target size. Note that this function makes no attempt to estimate
|
|
* how many suitable free blocks there *might* be if MOVABLE pages were
|
|
* migrated. Calculating that is possible, but expensive and can be
|
|
* figured out from userspace
|
|
*/
|
|
static void fill_contig_page_info(struct zone *zone,
|
|
unsigned int suitable_order,
|
|
struct contig_page_info *info)
|
|
{
|
|
unsigned int order;
|
|
|
|
info->free_pages = 0;
|
|
info->free_blocks_total = 0;
|
|
info->free_blocks_suitable = 0;
|
|
|
|
for (order = 0; order < MAX_ORDER; order++) {
|
|
unsigned long blocks;
|
|
|
|
/* Count number of free blocks */
|
|
blocks = zone->free_area[order].nr_free;
|
|
info->free_blocks_total += blocks;
|
|
|
|
/* Count free base pages */
|
|
info->free_pages += blocks << order;
|
|
|
|
/* Count the suitable free blocks */
|
|
if (order >= suitable_order)
|
|
info->free_blocks_suitable += blocks <<
|
|
(order - suitable_order);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* A fragmentation index only makes sense if an allocation of a requested
|
|
* size would fail. If that is true, the fragmentation index indicates
|
|
* whether external fragmentation or a lack of memory was the problem.
|
|
* The value can be used to determine if page reclaim or compaction
|
|
* should be used
|
|
*/
|
|
static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
|
|
{
|
|
unsigned long requested = 1UL << order;
|
|
|
|
if (WARN_ON_ONCE(order >= MAX_ORDER))
|
|
return 0;
|
|
|
|
if (!info->free_blocks_total)
|
|
return 0;
|
|
|
|
/* Fragmentation index only makes sense when a request would fail */
|
|
if (info->free_blocks_suitable)
|
|
return -1000;
|
|
|
|
/*
|
|
* Index is between 0 and 1 so return within 3 decimal places
|
|
*
|
|
* 0 => allocation would fail due to lack of memory
|
|
* 1 => allocation would fail due to fragmentation
|
|
*/
|
|
return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
|
|
}
|
|
|
|
/*
|
|
* Calculates external fragmentation within a zone wrt the given order.
|
|
* It is defined as the percentage of pages found in blocks of size
|
|
* less than 1 << order. It returns values in range [0, 100].
|
|
*/
|
|
unsigned int extfrag_for_order(struct zone *zone, unsigned int order)
|
|
{
|
|
struct contig_page_info info;
|
|
|
|
fill_contig_page_info(zone, order, &info);
|
|
if (info.free_pages == 0)
|
|
return 0;
|
|
|
|
return div_u64((info.free_pages -
|
|
(info.free_blocks_suitable << order)) * 100,
|
|
info.free_pages);
|
|
}
|
|
|
|
/* Same as __fragmentation index but allocs contig_page_info on stack */
|
|
int fragmentation_index(struct zone *zone, unsigned int order)
|
|
{
|
|
struct contig_page_info info;
|
|
|
|
fill_contig_page_info(zone, order, &info);
|
|
return __fragmentation_index(order, &info);
|
|
}
|
|
#endif
|
|
|
|
#if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || \
|
|
defined(CONFIG_NUMA) || defined(CONFIG_MEMCG)
|
|
#ifdef CONFIG_ZONE_DMA
|
|
#define TEXT_FOR_DMA(xx) xx "_dma",
|
|
#else
|
|
#define TEXT_FOR_DMA(xx)
|
|
#endif
|
|
|
|
#ifdef CONFIG_ZONE_DMA32
|
|
#define TEXT_FOR_DMA32(xx) xx "_dma32",
|
|
#else
|
|
#define TEXT_FOR_DMA32(xx)
|
|
#endif
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
#define TEXT_FOR_HIGHMEM(xx) xx "_high",
|
|
#else
|
|
#define TEXT_FOR_HIGHMEM(xx)
|
|
#endif
|
|
|
|
#define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
|
|
TEXT_FOR_HIGHMEM(xx) xx "_movable",
|
|
|
|
const char * const vmstat_text[] = {
|
|
/* enum zone_stat_item counters */
|
|
"nr_free_pages",
|
|
"nr_zone_inactive_anon",
|
|
"nr_zone_active_anon",
|
|
"nr_zone_inactive_file",
|
|
"nr_zone_active_file",
|
|
"nr_zone_unevictable",
|
|
"nr_zone_write_pending",
|
|
"nr_mlock",
|
|
"nr_bounce",
|
|
#if IS_ENABLED(CONFIG_ZSMALLOC)
|
|
"nr_zspages",
|
|
#endif
|
|
"nr_free_cma",
|
|
|
|
/* enum numa_stat_item counters */
|
|
#ifdef CONFIG_NUMA
|
|
"numa_hit",
|
|
"numa_miss",
|
|
"numa_foreign",
|
|
"numa_interleave",
|
|
"numa_local",
|
|
"numa_other",
|
|
#endif
|
|
|
|
/* enum node_stat_item counters */
|
|
"nr_inactive_anon",
|
|
"nr_active_anon",
|
|
"nr_inactive_file",
|
|
"nr_active_file",
|
|
"nr_unevictable",
|
|
"nr_slab_reclaimable",
|
|
"nr_slab_unreclaimable",
|
|
"nr_isolated_anon",
|
|
"nr_isolated_file",
|
|
"workingset_nodes",
|
|
"workingset_refault_anon",
|
|
"workingset_refault_file",
|
|
"workingset_activate_anon",
|
|
"workingset_activate_file",
|
|
"workingset_restore_anon",
|
|
"workingset_restore_file",
|
|
"workingset_nodereclaim",
|
|
"nr_anon_pages",
|
|
"nr_mapped",
|
|
"nr_file_pages",
|
|
"nr_dirty",
|
|
"nr_writeback",
|
|
"nr_writeback_temp",
|
|
"nr_shmem",
|
|
"nr_shmem_hugepages",
|
|
"nr_shmem_pmdmapped",
|
|
"nr_file_hugepages",
|
|
"nr_file_pmdmapped",
|
|
"nr_anon_transparent_hugepages",
|
|
"nr_vmscan_write",
|
|
"nr_vmscan_immediate_reclaim",
|
|
"nr_dirtied",
|
|
"nr_written",
|
|
"nr_kernel_misc_reclaimable",
|
|
"nr_foll_pin_acquired",
|
|
"nr_foll_pin_released",
|
|
"nr_kernel_stack",
|
|
#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK)
|
|
"nr_shadow_call_stack",
|
|
#endif
|
|
"nr_page_table_pages",
|
|
#ifdef CONFIG_SWAP
|
|
"nr_swapcached",
|
|
#endif
|
|
|
|
/* enum writeback_stat_item counters */
|
|
"nr_dirty_threshold",
|
|
"nr_dirty_background_threshold",
|
|
|
|
#if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
|
|
/* enum vm_event_item counters */
|
|
"pgpgin",
|
|
"pgpgout",
|
|
"pswpin",
|
|
"pswpout",
|
|
|
|
TEXTS_FOR_ZONES("pgalloc")
|
|
TEXTS_FOR_ZONES("allocstall")
|
|
TEXTS_FOR_ZONES("pgskip")
|
|
|
|
"pgfree",
|
|
"pgactivate",
|
|
"pgdeactivate",
|
|
"pglazyfree",
|
|
|
|
"pgfault",
|
|
"pgmajfault",
|
|
"pglazyfreed",
|
|
|
|
"pgrefill",
|
|
"pgreuse",
|
|
"pgsteal_kswapd",
|
|
"pgsteal_direct",
|
|
"pgdemote_kswapd",
|
|
"pgdemote_direct",
|
|
"pgscan_kswapd",
|
|
"pgscan_direct",
|
|
"pgscan_direct_throttle",
|
|
"pgscan_anon",
|
|
"pgscan_file",
|
|
"pgsteal_anon",
|
|
"pgsteal_file",
|
|
|
|
#ifdef CONFIG_NUMA
|
|
"zone_reclaim_failed",
|
|
#endif
|
|
"pginodesteal",
|
|
"slabs_scanned",
|
|
"kswapd_inodesteal",
|
|
"kswapd_low_wmark_hit_quickly",
|
|
"kswapd_high_wmark_hit_quickly",
|
|
"pageoutrun",
|
|
|
|
"pgrotated",
|
|
|
|
"drop_pagecache",
|
|
"drop_slab",
|
|
"oom_kill",
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
"numa_pte_updates",
|
|
"numa_huge_pte_updates",
|
|
"numa_hint_faults",
|
|
"numa_hint_faults_local",
|
|
"numa_pages_migrated",
|
|
#endif
|
|
#ifdef CONFIG_MIGRATION
|
|
"pgmigrate_success",
|
|
"pgmigrate_fail",
|
|
"thp_migration_success",
|
|
"thp_migration_fail",
|
|
"thp_migration_split",
|
|
#endif
|
|
#ifdef CONFIG_COMPACTION
|
|
"compact_migrate_scanned",
|
|
"compact_free_scanned",
|
|
"compact_isolated",
|
|
"compact_stall",
|
|
"compact_fail",
|
|
"compact_success",
|
|
"compact_daemon_wake",
|
|
"compact_daemon_migrate_scanned",
|
|
"compact_daemon_free_scanned",
|
|
#endif
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
"htlb_buddy_alloc_success",
|
|
"htlb_buddy_alloc_fail",
|
|
#endif
|
|
#ifdef CONFIG_CMA
|
|
"cma_alloc_success",
|
|
"cma_alloc_fail",
|
|
#endif
|
|
"unevictable_pgs_culled",
|
|
"unevictable_pgs_scanned",
|
|
"unevictable_pgs_rescued",
|
|
"unevictable_pgs_mlocked",
|
|
"unevictable_pgs_munlocked",
|
|
"unevictable_pgs_cleared",
|
|
"unevictable_pgs_stranded",
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
"thp_fault_alloc",
|
|
"thp_fault_fallback",
|
|
"thp_fault_fallback_charge",
|
|
"thp_collapse_alloc",
|
|
"thp_collapse_alloc_failed",
|
|
"thp_file_alloc",
|
|
"thp_file_fallback",
|
|
"thp_file_fallback_charge",
|
|
"thp_file_mapped",
|
|
"thp_split_page",
|
|
"thp_split_page_failed",
|
|
"thp_deferred_split_page",
|
|
"thp_split_pmd",
|
|
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
|
|
"thp_split_pud",
|
|
#endif
|
|
"thp_zero_page_alloc",
|
|
"thp_zero_page_alloc_failed",
|
|
"thp_swpout",
|
|
"thp_swpout_fallback",
|
|
#endif
|
|
#ifdef CONFIG_MEMORY_BALLOON
|
|
"balloon_inflate",
|
|
"balloon_deflate",
|
|
#ifdef CONFIG_BALLOON_COMPACTION
|
|
"balloon_migrate",
|
|
#endif
|
|
#endif /* CONFIG_MEMORY_BALLOON */
|
|
#ifdef CONFIG_DEBUG_TLBFLUSH
|
|
"nr_tlb_remote_flush",
|
|
"nr_tlb_remote_flush_received",
|
|
"nr_tlb_local_flush_all",
|
|
"nr_tlb_local_flush_one",
|
|
#endif /* CONFIG_DEBUG_TLBFLUSH */
|
|
|
|
#ifdef CONFIG_DEBUG_VM_VMACACHE
|
|
"vmacache_find_calls",
|
|
"vmacache_find_hits",
|
|
#endif
|
|
#ifdef CONFIG_SWAP
|
|
"swap_ra",
|
|
"swap_ra_hit",
|
|
#endif
|
|
#ifdef CONFIG_X86
|
|
"direct_map_level2_splits",
|
|
"direct_map_level3_splits",
|
|
#endif
|
|
#endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */
|
|
};
|
|
#endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA || CONFIG_MEMCG */
|
|
|
|
#if (defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)) || \
|
|
defined(CONFIG_PROC_FS)
|
|
static void *frag_start(struct seq_file *m, loff_t *pos)
|
|
{
|
|
pg_data_t *pgdat;
|
|
loff_t node = *pos;
|
|
|
|
for (pgdat = first_online_pgdat();
|
|
pgdat && node;
|
|
pgdat = next_online_pgdat(pgdat))
|
|
--node;
|
|
|
|
return pgdat;
|
|
}
|
|
|
|
static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
|
|
{
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
|
|
(*pos)++;
|
|
return next_online_pgdat(pgdat);
|
|
}
|
|
|
|
static void frag_stop(struct seq_file *m, void *arg)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* Walk zones in a node and print using a callback.
|
|
* If @assert_populated is true, only use callback for zones that are populated.
|
|
*/
|
|
static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
|
|
bool assert_populated, bool nolock,
|
|
void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
|
|
{
|
|
struct zone *zone;
|
|
struct zone *node_zones = pgdat->node_zones;
|
|
unsigned long flags;
|
|
|
|
for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
|
|
if (assert_populated && !populated_zone(zone))
|
|
continue;
|
|
|
|
if (!nolock)
|
|
spin_lock_irqsave(&zone->lock, flags);
|
|
print(m, pgdat, zone);
|
|
if (!nolock)
|
|
spin_unlock_irqrestore(&zone->lock, flags);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
|
|
struct zone *zone)
|
|
{
|
|
int order;
|
|
|
|
seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
|
|
for (order = 0; order < MAX_ORDER; ++order)
|
|
seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
/*
|
|
* This walks the free areas for each zone.
|
|
*/
|
|
static int frag_show(struct seq_file *m, void *arg)
|
|
{
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
walk_zones_in_node(m, pgdat, true, false, frag_show_print);
|
|
return 0;
|
|
}
|
|
|
|
static void pagetypeinfo_showfree_print(struct seq_file *m,
|
|
pg_data_t *pgdat, struct zone *zone)
|
|
{
|
|
int order, mtype;
|
|
|
|
for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
|
|
seq_printf(m, "Node %4d, zone %8s, type %12s ",
|
|
pgdat->node_id,
|
|
zone->name,
|
|
migratetype_names[mtype]);
|
|
for (order = 0; order < MAX_ORDER; ++order) {
|
|
unsigned long freecount = 0;
|
|
struct free_area *area;
|
|
struct list_head *curr;
|
|
bool overflow = false;
|
|
|
|
area = &(zone->free_area[order]);
|
|
|
|
list_for_each(curr, &area->free_list[mtype]) {
|
|
/*
|
|
* Cap the free_list iteration because it might
|
|
* be really large and we are under a spinlock
|
|
* so a long time spent here could trigger a
|
|
* hard lockup detector. Anyway this is a
|
|
* debugging tool so knowing there is a handful
|
|
* of pages of this order should be more than
|
|
* sufficient.
|
|
*/
|
|
if (++freecount >= 100000) {
|
|
overflow = true;
|
|
break;
|
|
}
|
|
}
|
|
seq_printf(m, "%s%6lu ", overflow ? ">" : "", freecount);
|
|
spin_unlock_irq(&zone->lock);
|
|
cond_resched();
|
|
spin_lock_irq(&zone->lock);
|
|
}
|
|
seq_putc(m, '\n');
|
|
}
|
|
}
|
|
|
|
/* Print out the free pages at each order for each migatetype */
|
|
static void pagetypeinfo_showfree(struct seq_file *m, void *arg)
|
|
{
|
|
int order;
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
|
|
/* Print header */
|
|
seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
|
|
for (order = 0; order < MAX_ORDER; ++order)
|
|
seq_printf(m, "%6d ", order);
|
|
seq_putc(m, '\n');
|
|
|
|
walk_zones_in_node(m, pgdat, true, false, pagetypeinfo_showfree_print);
|
|
}
|
|
|
|
static void pagetypeinfo_showblockcount_print(struct seq_file *m,
|
|
pg_data_t *pgdat, struct zone *zone)
|
|
{
|
|
int mtype;
|
|
unsigned long pfn;
|
|
unsigned long start_pfn = zone->zone_start_pfn;
|
|
unsigned long end_pfn = zone_end_pfn(zone);
|
|
unsigned long count[MIGRATE_TYPES] = { 0, };
|
|
|
|
for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
|
|
struct page *page;
|
|
|
|
page = pfn_to_online_page(pfn);
|
|
if (!page)
|
|
continue;
|
|
|
|
if (page_zone(page) != zone)
|
|
continue;
|
|
|
|
mtype = get_pageblock_migratetype(page);
|
|
|
|
if (mtype < MIGRATE_TYPES)
|
|
count[mtype]++;
|
|
}
|
|
|
|
/* Print counts */
|
|
seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
|
|
for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
|
|
seq_printf(m, "%12lu ", count[mtype]);
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
/* Print out the number of pageblocks for each migratetype */
|
|
static void pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
|
|
{
|
|
int mtype;
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
|
|
seq_printf(m, "\n%-23s", "Number of blocks type ");
|
|
for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
|
|
seq_printf(m, "%12s ", migratetype_names[mtype]);
|
|
seq_putc(m, '\n');
|
|
walk_zones_in_node(m, pgdat, true, false,
|
|
pagetypeinfo_showblockcount_print);
|
|
}
|
|
|
|
/*
|
|
* Print out the number of pageblocks for each migratetype that contain pages
|
|
* of other types. This gives an indication of how well fallbacks are being
|
|
* contained by rmqueue_fallback(). It requires information from PAGE_OWNER
|
|
* to determine what is going on
|
|
*/
|
|
static void pagetypeinfo_showmixedcount(struct seq_file *m, pg_data_t *pgdat)
|
|
{
|
|
#ifdef CONFIG_PAGE_OWNER
|
|
int mtype;
|
|
|
|
if (!static_branch_unlikely(&page_owner_inited))
|
|
return;
|
|
|
|
drain_all_pages(NULL);
|
|
|
|
seq_printf(m, "\n%-23s", "Number of mixed blocks ");
|
|
for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
|
|
seq_printf(m, "%12s ", migratetype_names[mtype]);
|
|
seq_putc(m, '\n');
|
|
|
|
walk_zones_in_node(m, pgdat, true, true,
|
|
pagetypeinfo_showmixedcount_print);
|
|
#endif /* CONFIG_PAGE_OWNER */
|
|
}
|
|
|
|
/*
|
|
* This prints out statistics in relation to grouping pages by mobility.
|
|
* It is expensive to collect so do not constantly read the file.
|
|
*/
|
|
static int pagetypeinfo_show(struct seq_file *m, void *arg)
|
|
{
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
|
|
/* check memoryless node */
|
|
if (!node_state(pgdat->node_id, N_MEMORY))
|
|
return 0;
|
|
|
|
seq_printf(m, "Page block order: %d\n", pageblock_order);
|
|
seq_printf(m, "Pages per block: %lu\n", pageblock_nr_pages);
|
|
seq_putc(m, '\n');
|
|
pagetypeinfo_showfree(m, pgdat);
|
|
pagetypeinfo_showblockcount(m, pgdat);
|
|
pagetypeinfo_showmixedcount(m, pgdat);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations fragmentation_op = {
|
|
.start = frag_start,
|
|
.next = frag_next,
|
|
.stop = frag_stop,
|
|
.show = frag_show,
|
|
};
|
|
|
|
static const struct seq_operations pagetypeinfo_op = {
|
|
.start = frag_start,
|
|
.next = frag_next,
|
|
.stop = frag_stop,
|
|
.show = pagetypeinfo_show,
|
|
};
|
|
|
|
static bool is_zone_first_populated(pg_data_t *pgdat, struct zone *zone)
|
|
{
|
|
int zid;
|
|
|
|
for (zid = 0; zid < MAX_NR_ZONES; zid++) {
|
|
struct zone *compare = &pgdat->node_zones[zid];
|
|
|
|
if (populated_zone(compare))
|
|
return zone == compare;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
|
|
struct zone *zone)
|
|
{
|
|
int i;
|
|
seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
|
|
if (is_zone_first_populated(pgdat, zone)) {
|
|
seq_printf(m, "\n per-node stats");
|
|
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
|
|
unsigned long pages = node_page_state_pages(pgdat, i);
|
|
|
|
if (vmstat_item_print_in_thp(i))
|
|
pages /= HPAGE_PMD_NR;
|
|
seq_printf(m, "\n %-12s %lu", node_stat_name(i),
|
|
pages);
|
|
}
|
|
}
|
|
seq_printf(m,
|
|
"\n pages free %lu"
|
|
"\n min %lu"
|
|
"\n low %lu"
|
|
"\n high %lu"
|
|
"\n spanned %lu"
|
|
"\n present %lu"
|
|
"\n managed %lu"
|
|
"\n cma %lu",
|
|
zone_page_state(zone, NR_FREE_PAGES),
|
|
min_wmark_pages(zone),
|
|
low_wmark_pages(zone),
|
|
high_wmark_pages(zone),
|
|
zone->spanned_pages,
|
|
zone->present_pages,
|
|
zone_managed_pages(zone),
|
|
zone_cma_pages(zone));
|
|
|
|
seq_printf(m,
|
|
"\n protection: (%ld",
|
|
zone->lowmem_reserve[0]);
|
|
for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
|
|
seq_printf(m, ", %ld", zone->lowmem_reserve[i]);
|
|
seq_putc(m, ')');
|
|
|
|
/* If unpopulated, no other information is useful */
|
|
if (!populated_zone(zone)) {
|
|
seq_putc(m, '\n');
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
|
|
seq_printf(m, "\n %-12s %lu", zone_stat_name(i),
|
|
zone_page_state(zone, i));
|
|
|
|
#ifdef CONFIG_NUMA
|
|
for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++)
|
|
seq_printf(m, "\n %-12s %lu", numa_stat_name(i),
|
|
zone_numa_event_state(zone, i));
|
|
#endif
|
|
|
|
seq_printf(m, "\n pagesets");
|
|
for_each_online_cpu(i) {
|
|
struct per_cpu_pages *pcp;
|
|
struct per_cpu_zonestat __maybe_unused *pzstats;
|
|
|
|
pcp = per_cpu_ptr(zone->per_cpu_pageset, i);
|
|
seq_printf(m,
|
|
"\n cpu: %i"
|
|
"\n count: %i"
|
|
"\n high: %i"
|
|
"\n batch: %i",
|
|
i,
|
|
pcp->count,
|
|
pcp->high,
|
|
pcp->batch);
|
|
#ifdef CONFIG_SMP
|
|
pzstats = per_cpu_ptr(zone->per_cpu_zonestats, i);
|
|
seq_printf(m, "\n vm stats threshold: %d",
|
|
pzstats->stat_threshold);
|
|
#endif
|
|
}
|
|
seq_printf(m,
|
|
"\n node_unreclaimable: %u"
|
|
"\n start_pfn: %lu",
|
|
pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES,
|
|
zone->zone_start_pfn);
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
/*
|
|
* Output information about zones in @pgdat. All zones are printed regardless
|
|
* of whether they are populated or not: lowmem_reserve_ratio operates on the
|
|
* set of all zones and userspace would not be aware of such zones if they are
|
|
* suppressed here (zoneinfo displays the effect of lowmem_reserve_ratio).
|
|
*/
|
|
static int zoneinfo_show(struct seq_file *m, void *arg)
|
|
{
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
walk_zones_in_node(m, pgdat, false, false, zoneinfo_show_print);
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations zoneinfo_op = {
|
|
.start = frag_start, /* iterate over all zones. The same as in
|
|
* fragmentation. */
|
|
.next = frag_next,
|
|
.stop = frag_stop,
|
|
.show = zoneinfo_show,
|
|
};
|
|
|
|
#define NR_VMSTAT_ITEMS (NR_VM_ZONE_STAT_ITEMS + \
|
|
NR_VM_NUMA_EVENT_ITEMS + \
|
|
NR_VM_NODE_STAT_ITEMS + \
|
|
NR_VM_WRITEBACK_STAT_ITEMS + \
|
|
(IS_ENABLED(CONFIG_VM_EVENT_COUNTERS) ? \
|
|
NR_VM_EVENT_ITEMS : 0))
|
|
|
|
static void *vmstat_start(struct seq_file *m, loff_t *pos)
|
|
{
|
|
unsigned long *v;
|
|
int i;
|
|
|
|
if (*pos >= NR_VMSTAT_ITEMS)
|
|
return NULL;
|
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(vmstat_text) < NR_VMSTAT_ITEMS);
|
|
fold_vm_numa_events();
|
|
v = kmalloc_array(NR_VMSTAT_ITEMS, sizeof(unsigned long), GFP_KERNEL);
|
|
m->private = v;
|
|
if (!v)
|
|
return ERR_PTR(-ENOMEM);
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
|
|
v[i] = global_zone_page_state(i);
|
|
v += NR_VM_ZONE_STAT_ITEMS;
|
|
|
|
#ifdef CONFIG_NUMA
|
|
for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++)
|
|
v[i] = global_numa_event_state(i);
|
|
v += NR_VM_NUMA_EVENT_ITEMS;
|
|
#endif
|
|
|
|
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
|
|
v[i] = global_node_page_state_pages(i);
|
|
if (vmstat_item_print_in_thp(i))
|
|
v[i] /= HPAGE_PMD_NR;
|
|
}
|
|
v += NR_VM_NODE_STAT_ITEMS;
|
|
|
|
global_dirty_limits(v + NR_DIRTY_BG_THRESHOLD,
|
|
v + NR_DIRTY_THRESHOLD);
|
|
v += NR_VM_WRITEBACK_STAT_ITEMS;
|
|
|
|
#ifdef CONFIG_VM_EVENT_COUNTERS
|
|
all_vm_events(v);
|
|
v[PGPGIN] /= 2; /* sectors -> kbytes */
|
|
v[PGPGOUT] /= 2;
|
|
#endif
|
|
return (unsigned long *)m->private + *pos;
|
|
}
|
|
|
|
static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
|
|
{
|
|
(*pos)++;
|
|
if (*pos >= NR_VMSTAT_ITEMS)
|
|
return NULL;
|
|
return (unsigned long *)m->private + *pos;
|
|
}
|
|
|
|
static int vmstat_show(struct seq_file *m, void *arg)
|
|
{
|
|
unsigned long *l = arg;
|
|
unsigned long off = l - (unsigned long *)m->private;
|
|
|
|
seq_puts(m, vmstat_text[off]);
|
|
seq_put_decimal_ull(m, " ", *l);
|
|
seq_putc(m, '\n');
|
|
|
|
if (off == NR_VMSTAT_ITEMS - 1) {
|
|
/*
|
|
* We've come to the end - add any deprecated counters to avoid
|
|
* breaking userspace which might depend on them being present.
|
|
*/
|
|
seq_puts(m, "nr_unstable 0\n");
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void vmstat_stop(struct seq_file *m, void *arg)
|
|
{
|
|
kfree(m->private);
|
|
m->private = NULL;
|
|
}
|
|
|
|
static const struct seq_operations vmstat_op = {
|
|
.start = vmstat_start,
|
|
.next = vmstat_next,
|
|
.stop = vmstat_stop,
|
|
.show = vmstat_show,
|
|
};
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
#ifdef CONFIG_SMP
|
|
static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
|
|
int sysctl_stat_interval __read_mostly = HZ;
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void refresh_vm_stats(struct work_struct *work)
|
|
{
|
|
refresh_cpu_vm_stats(true);
|
|
}
|
|
|
|
int vmstat_refresh(struct ctl_table *table, int write,
|
|
void *buffer, size_t *lenp, loff_t *ppos)
|
|
{
|
|
long val;
|
|
int err;
|
|
int i;
|
|
|
|
/*
|
|
* The regular update, every sysctl_stat_interval, may come later
|
|
* than expected: leaving a significant amount in per_cpu buckets.
|
|
* This is particularly misleading when checking a quantity of HUGE
|
|
* pages, immediately after running a test. /proc/sys/vm/stat_refresh,
|
|
* which can equally be echo'ed to or cat'ted from (by root),
|
|
* can be used to update the stats just before reading them.
|
|
*
|
|
* Oh, and since global_zone_page_state() etc. are so careful to hide
|
|
* transiently negative values, report an error here if any of
|
|
* the stats is negative, so we know to go looking for imbalance.
|
|
*/
|
|
err = schedule_on_each_cpu(refresh_vm_stats);
|
|
if (err)
|
|
return err;
|
|
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
|
|
/*
|
|
* Skip checking stats known to go negative occasionally.
|
|
*/
|
|
switch (i) {
|
|
case NR_ZONE_WRITE_PENDING:
|
|
case NR_FREE_CMA_PAGES:
|
|
continue;
|
|
}
|
|
val = atomic_long_read(&vm_zone_stat[i]);
|
|
if (val < 0) {
|
|
pr_warn("%s: %s %ld\n",
|
|
__func__, zone_stat_name(i), val);
|
|
}
|
|
}
|
|
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
|
|
/*
|
|
* Skip checking stats known to go negative occasionally.
|
|
*/
|
|
switch (i) {
|
|
case NR_WRITEBACK:
|
|
continue;
|
|
}
|
|
val = atomic_long_read(&vm_node_stat[i]);
|
|
if (val < 0) {
|
|
pr_warn("%s: %s %ld\n",
|
|
__func__, node_stat_name(i), val);
|
|
}
|
|
}
|
|
if (write)
|
|
*ppos += *lenp;
|
|
else
|
|
*lenp = 0;
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
static void vmstat_update(struct work_struct *w)
|
|
{
|
|
if (refresh_cpu_vm_stats(true)) {
|
|
/*
|
|
* Counters were updated so we expect more updates
|
|
* to occur in the future. Keep on running the
|
|
* update worker thread.
|
|
*/
|
|
queue_delayed_work_on(smp_processor_id(), mm_percpu_wq,
|
|
this_cpu_ptr(&vmstat_work),
|
|
round_jiffies_relative(sysctl_stat_interval));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check if the diffs for a certain cpu indicate that
|
|
* an update is needed.
|
|
*/
|
|
static bool need_update(int cpu)
|
|
{
|
|
pg_data_t *last_pgdat = NULL;
|
|
struct zone *zone;
|
|
|
|
for_each_populated_zone(zone) {
|
|
struct per_cpu_zonestat *pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu);
|
|
struct per_cpu_nodestat *n;
|
|
|
|
/*
|
|
* The fast way of checking if there are any vmstat diffs.
|
|
*/
|
|
if (memchr_inv(pzstats->vm_stat_diff, 0, sizeof(pzstats->vm_stat_diff)))
|
|
return true;
|
|
|
|
if (last_pgdat == zone->zone_pgdat)
|
|
continue;
|
|
last_pgdat = zone->zone_pgdat;
|
|
n = per_cpu_ptr(zone->zone_pgdat->per_cpu_nodestats, cpu);
|
|
if (memchr_inv(n->vm_node_stat_diff, 0, sizeof(n->vm_node_stat_diff)))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Switch off vmstat processing and then fold all the remaining differentials
|
|
* until the diffs stay at zero. The function is used by NOHZ and can only be
|
|
* invoked when tick processing is not active.
|
|
*/
|
|
void quiet_vmstat(void)
|
|
{
|
|
if (system_state != SYSTEM_RUNNING)
|
|
return;
|
|
|
|
if (!delayed_work_pending(this_cpu_ptr(&vmstat_work)))
|
|
return;
|
|
|
|
if (!need_update(smp_processor_id()))
|
|
return;
|
|
|
|
/*
|
|
* Just refresh counters and do not care about the pending delayed
|
|
* vmstat_update. It doesn't fire that often to matter and canceling
|
|
* it would be too expensive from this path.
|
|
* vmstat_shepherd will take care about that for us.
|
|
*/
|
|
refresh_cpu_vm_stats(false);
|
|
}
|
|
|
|
/*
|
|
* Shepherd worker thread that checks the
|
|
* differentials of processors that have their worker
|
|
* threads for vm statistics updates disabled because of
|
|
* inactivity.
|
|
*/
|
|
static void vmstat_shepherd(struct work_struct *w);
|
|
|
|
static DECLARE_DEFERRABLE_WORK(shepherd, vmstat_shepherd);
|
|
|
|
static void vmstat_shepherd(struct work_struct *w)
|
|
{
|
|
int cpu;
|
|
|
|
cpus_read_lock();
|
|
/* Check processors whose vmstat worker threads have been disabled */
|
|
for_each_online_cpu(cpu) {
|
|
struct delayed_work *dw = &per_cpu(vmstat_work, cpu);
|
|
|
|
if (!delayed_work_pending(dw) && need_update(cpu))
|
|
queue_delayed_work_on(cpu, mm_percpu_wq, dw, 0);
|
|
|
|
cond_resched();
|
|
}
|
|
cpus_read_unlock();
|
|
|
|
schedule_delayed_work(&shepherd,
|
|
round_jiffies_relative(sysctl_stat_interval));
|
|
}
|
|
|
|
static void __init start_shepherd_timer(void)
|
|
{
|
|
int cpu;
|
|
|
|
for_each_possible_cpu(cpu)
|
|
INIT_DEFERRABLE_WORK(per_cpu_ptr(&vmstat_work, cpu),
|
|
vmstat_update);
|
|
|
|
schedule_delayed_work(&shepherd,
|
|
round_jiffies_relative(sysctl_stat_interval));
|
|
}
|
|
|
|
static void __init init_cpu_node_state(void)
|
|
{
|
|
int node;
|
|
|
|
for_each_online_node(node) {
|
|
if (cpumask_weight(cpumask_of_node(node)) > 0)
|
|
node_set_state(node, N_CPU);
|
|
}
|
|
}
|
|
|
|
static int vmstat_cpu_online(unsigned int cpu)
|
|
{
|
|
refresh_zone_stat_thresholds();
|
|
node_set_state(cpu_to_node(cpu), N_CPU);
|
|
return 0;
|
|
}
|
|
|
|
static int vmstat_cpu_down_prep(unsigned int cpu)
|
|
{
|
|
cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
|
|
return 0;
|
|
}
|
|
|
|
static int vmstat_cpu_dead(unsigned int cpu)
|
|
{
|
|
const struct cpumask *node_cpus;
|
|
int node;
|
|
|
|
node = cpu_to_node(cpu);
|
|
|
|
refresh_zone_stat_thresholds();
|
|
node_cpus = cpumask_of_node(node);
|
|
if (cpumask_weight(node_cpus) > 0)
|
|
return 0;
|
|
|
|
node_clear_state(node, N_CPU);
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
|
|
struct workqueue_struct *mm_percpu_wq;
|
|
|
|
void __init init_mm_internals(void)
|
|
{
|
|
int ret __maybe_unused;
|
|
|
|
mm_percpu_wq = alloc_workqueue("mm_percpu_wq", WQ_MEM_RECLAIM, 0);
|
|
|
|
#ifdef CONFIG_SMP
|
|
ret = cpuhp_setup_state_nocalls(CPUHP_MM_VMSTAT_DEAD, "mm/vmstat:dead",
|
|
NULL, vmstat_cpu_dead);
|
|
if (ret < 0)
|
|
pr_err("vmstat: failed to register 'dead' hotplug state\n");
|
|
|
|
ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "mm/vmstat:online",
|
|
vmstat_cpu_online,
|
|
vmstat_cpu_down_prep);
|
|
if (ret < 0)
|
|
pr_err("vmstat: failed to register 'online' hotplug state\n");
|
|
|
|
cpus_read_lock();
|
|
init_cpu_node_state();
|
|
cpus_read_unlock();
|
|
|
|
start_shepherd_timer();
|
|
#endif
|
|
#ifdef CONFIG_PROC_FS
|
|
proc_create_seq("buddyinfo", 0444, NULL, &fragmentation_op);
|
|
proc_create_seq("pagetypeinfo", 0400, NULL, &pagetypeinfo_op);
|
|
proc_create_seq("vmstat", 0444, NULL, &vmstat_op);
|
|
proc_create_seq("zoneinfo", 0444, NULL, &zoneinfo_op);
|
|
#endif
|
|
}
|
|
|
|
#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
|
|
|
|
/*
|
|
* Return an index indicating how much of the available free memory is
|
|
* unusable for an allocation of the requested size.
|
|
*/
|
|
static int unusable_free_index(unsigned int order,
|
|
struct contig_page_info *info)
|
|
{
|
|
/* No free memory is interpreted as all free memory is unusable */
|
|
if (info->free_pages == 0)
|
|
return 1000;
|
|
|
|
/*
|
|
* Index should be a value between 0 and 1. Return a value to 3
|
|
* decimal places.
|
|
*
|
|
* 0 => no fragmentation
|
|
* 1 => high fragmentation
|
|
*/
|
|
return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
|
|
|
|
}
|
|
|
|
static void unusable_show_print(struct seq_file *m,
|
|
pg_data_t *pgdat, struct zone *zone)
|
|
{
|
|
unsigned int order;
|
|
int index;
|
|
struct contig_page_info info;
|
|
|
|
seq_printf(m, "Node %d, zone %8s ",
|
|
pgdat->node_id,
|
|
zone->name);
|
|
for (order = 0; order < MAX_ORDER; ++order) {
|
|
fill_contig_page_info(zone, order, &info);
|
|
index = unusable_free_index(order, &info);
|
|
seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
|
|
}
|
|
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
/*
|
|
* Display unusable free space index
|
|
*
|
|
* The unusable free space index measures how much of the available free
|
|
* memory cannot be used to satisfy an allocation of a given size and is a
|
|
* value between 0 and 1. The higher the value, the more of free memory is
|
|
* unusable and by implication, the worse the external fragmentation is. This
|
|
* can be expressed as a percentage by multiplying by 100.
|
|
*/
|
|
static int unusable_show(struct seq_file *m, void *arg)
|
|
{
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
|
|
/* check memoryless node */
|
|
if (!node_state(pgdat->node_id, N_MEMORY))
|
|
return 0;
|
|
|
|
walk_zones_in_node(m, pgdat, true, false, unusable_show_print);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations unusable_sops = {
|
|
.start = frag_start,
|
|
.next = frag_next,
|
|
.stop = frag_stop,
|
|
.show = unusable_show,
|
|
};
|
|
|
|
DEFINE_SEQ_ATTRIBUTE(unusable);
|
|
|
|
static void extfrag_show_print(struct seq_file *m,
|
|
pg_data_t *pgdat, struct zone *zone)
|
|
{
|
|
unsigned int order;
|
|
int index;
|
|
|
|
/* Alloc on stack as interrupts are disabled for zone walk */
|
|
struct contig_page_info info;
|
|
|
|
seq_printf(m, "Node %d, zone %8s ",
|
|
pgdat->node_id,
|
|
zone->name);
|
|
for (order = 0; order < MAX_ORDER; ++order) {
|
|
fill_contig_page_info(zone, order, &info);
|
|
index = __fragmentation_index(order, &info);
|
|
seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
|
|
}
|
|
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
/*
|
|
* Display fragmentation index for orders that allocations would fail for
|
|
*/
|
|
static int extfrag_show(struct seq_file *m, void *arg)
|
|
{
|
|
pg_data_t *pgdat = (pg_data_t *)arg;
|
|
|
|
walk_zones_in_node(m, pgdat, true, false, extfrag_show_print);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations extfrag_sops = {
|
|
.start = frag_start,
|
|
.next = frag_next,
|
|
.stop = frag_stop,
|
|
.show = extfrag_show,
|
|
};
|
|
|
|
DEFINE_SEQ_ATTRIBUTE(extfrag);
|
|
|
|
static int __init extfrag_debug_init(void)
|
|
{
|
|
struct dentry *extfrag_debug_root;
|
|
|
|
extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
|
|
|
|
debugfs_create_file("unusable_index", 0444, extfrag_debug_root, NULL,
|
|
&unusable_fops);
|
|
|
|
debugfs_create_file("extfrag_index", 0444, extfrag_debug_root, NULL,
|
|
&extfrag_fops);
|
|
|
|
return 0;
|
|
}
|
|
|
|
module_init(extfrag_debug_init);
|
|
#endif
|