| /* |
| * linux/mm/vmstat.c |
| * |
| * Manages VM statistics |
| * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
| * |
| * zoned VM statistics |
| * Copyright (C) 2006 Silicon Graphics, Inc., |
| * Christoph Lameter <christoph@lameter.com> |
| */ |
| #include <linux/fs.h> |
| #include <linux/mm.h> |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/cpu.h> |
| #include <linux/vmstat.h> |
| #include <linux/sched.h> |
| #include <linux/math64.h> |
| #include <linux/writeback.h> |
| #include <linux/compaction.h> |
| #include <linux/mm_inline.h> |
| |
| #include "internal.h" |
| |
| #ifdef CONFIG_VM_EVENT_COUNTERS |
| DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}}; |
| EXPORT_PER_CPU_SYMBOL(vm_event_states); |
| |
| static void sum_vm_events(unsigned long *ret) |
| { |
| int cpu; |
| int i; |
| |
| memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long)); |
| |
| for_each_online_cpu(cpu) { |
| struct vm_event_state *this = &per_cpu(vm_event_states, cpu); |
| |
| for (i = 0; i < NR_VM_EVENT_ITEMS; i++) |
| ret[i] += this->event[i]; |
| } |
| } |
| |
| /* |
| * Accumulate the vm event counters across all CPUs. |
| * The result is unavoidably approximate - it can change |
| * during and after execution of this function. |
| */ |
| void all_vm_events(unsigned long *ret) |
| { |
| get_online_cpus(); |
| sum_vm_events(ret); |
| put_online_cpus(); |
| } |
| EXPORT_SYMBOL_GPL(all_vm_events); |
| |
| /* |
| * Fold the foreign cpu events into our own. |
| * |
| * This is adding to the events on one processor |
| * but keeps the global counts constant. |
| */ |
| void vm_events_fold_cpu(int cpu) |
| { |
| struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu); |
| int i; |
| |
| for (i = 0; i < NR_VM_EVENT_ITEMS; i++) { |
| count_vm_events(i, fold_state->event[i]); |
| fold_state->event[i] = 0; |
| } |
| } |
| |
| #endif /* CONFIG_VM_EVENT_COUNTERS */ |
| |
| /* |
| * Manage combined zone based / global counters |
| * |
| * vm_stat contains the global counters |
| */ |
| atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS] __cacheline_aligned_in_smp; |
| EXPORT_SYMBOL(vm_stat); |
| |
| #ifdef CONFIG_SMP |
| |
| int calculate_pressure_threshold(struct zone *zone) |
| { |
| int threshold; |
| int watermark_distance; |
| |
| /* |
| * As vmstats are not up to date, there is drift between the estimated |
| * and real values. For high thresholds and a high number of CPUs, it |
| * is possible for the min watermark to be breached while the estimated |
| * value looks fine. The pressure threshold is a reduced value such |
| * that even the maximum amount of drift will not accidentally breach |
| * the min watermark |
| */ |
| watermark_distance = low_wmark_pages(zone) - min_wmark_pages(zone); |
| threshold = max(1, (int)(watermark_distance / num_online_cpus())); |
| |
| /* |
| * Maximum threshold is 125 |
| */ |
| threshold = min(125, threshold); |
| |
| return threshold; |
| } |
| |
| int calculate_normal_threshold(struct zone *zone) |
| { |
| int threshold; |
| int mem; /* memory in 128 MB units */ |
| |
| /* |
| * The threshold scales with the number of processors and the amount |
| * of memory per zone. More memory means that we can defer updates for |
| * longer, more processors could lead to more contention. |
| * fls() is used to have a cheap way of logarithmic scaling. |
| * |
| * Some sample thresholds: |
| * |
| * Threshold Processors (fls) Zonesize fls(mem+1) |
| * ------------------------------------------------------------------ |
| * 8 1 1 0.9-1 GB 4 |
| * 16 2 2 0.9-1 GB 4 |
| * 20 2 2 1-2 GB 5 |
| * 24 2 2 2-4 GB 6 |
| * 28 2 2 4-8 GB 7 |
| * 32 2 2 8-16 GB 8 |
| * 4 2 2 <128M 1 |
| * 30 4 3 2-4 GB 5 |
| * 48 4 3 8-16 GB 8 |
| * 32 8 4 1-2 GB 4 |
| * 32 8 4 0.9-1GB 4 |
| * 10 16 5 <128M 1 |
| * 40 16 5 900M 4 |
| * 70 64 7 2-4 GB 5 |
| * 84 64 7 4-8 GB 6 |
| * 108 512 9 4-8 GB 6 |
| * 125 1024 10 8-16 GB 8 |
| * 125 1024 10 16-32 GB 9 |
| */ |
| |
| mem = zone->managed_pages >> (27 - PAGE_SHIFT); |
| |
| threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem)); |
| |
| /* |
| * Maximum threshold is 125 |
| */ |
| threshold = min(125, threshold); |
| |
| return threshold; |
| } |
| |
| /* |
| * Refresh the thresholds for each zone. |
| */ |
| void refresh_zone_stat_thresholds(void) |
| { |
| struct zone *zone; |
| int cpu; |
| int threshold; |
| |
| for_each_populated_zone(zone) { |
| unsigned long max_drift, tolerate_drift; |
| |
| threshold = calculate_normal_threshold(zone); |
| |
| for_each_online_cpu(cpu) |
| per_cpu_ptr(zone->pageset, cpu)->stat_threshold |
| = threshold; |
| |
| /* |
| * Only set percpu_drift_mark if there is a danger that |
| * NR_FREE_PAGES reports the low watermark is ok when in fact |
| * the min watermark could be breached by an allocation |
| */ |
| tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone); |
| max_drift = num_online_cpus() * threshold; |
| if (max_drift > tolerate_drift) |
| zone->percpu_drift_mark = high_wmark_pages(zone) + |
| max_drift; |
| } |
| } |
| |
| void set_pgdat_percpu_threshold(pg_data_t *pgdat, |
| int (*calculate_pressure)(struct zone *)) |
| { |
| struct zone *zone; |
| int cpu; |
| int threshold; |
| int i; |
| |
| for (i = 0; i < pgdat->nr_zones; i++) { |
| zone = &pgdat->node_zones[i]; |
| if (!zone->percpu_drift_mark) |
| continue; |
| |
| threshold = (*calculate_pressure)(zone); |
| for_each_possible_cpu(cpu) |
| per_cpu_ptr(zone->pageset, cpu)->stat_threshold |
| = threshold; |
| } |
| } |
| |
| /* |
| * For use when we know that interrupts are disabled, |
| * or when we know that preemption is disabled and that |
| * particular counter cannot be updated from interrupt context. |
| */ |
| void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item, |
| int delta) |
| { |
| struct per_cpu_pageset __percpu *pcp = zone->pageset; |
| s8 __percpu *p = pcp->vm_stat_diff + item; |
| long x; |
| long t; |
| |
| x = delta + __this_cpu_read(*p); |
| |
| t = __this_cpu_read(pcp->stat_threshold); |
| |
| if (unlikely(x > t || x < -t)) { |
| zone_page_state_add(x, zone, item); |
| x = 0; |
| } |
| __this_cpu_write(*p, x); |
| } |
| EXPORT_SYMBOL(__mod_zone_page_state); |
| |
| /* |
| * Optimized increment and decrement functions. |
| * |
| * These are only for a single page and therefore can take a struct page * |
| * argument instead of struct zone *. This allows the inclusion of the code |
| * generated for page_zone(page) into the optimized functions. |
| * |
| * No overflow check is necessary and therefore the differential can be |
| * incremented or decremented in place which may allow the compilers to |
| * generate better code. |
| * The increment or decrement is known and therefore one boundary check can |
| * be omitted. |
| * |
| * NOTE: These functions are very performance sensitive. Change only |
| * with care. |
| * |
| * Some processors have inc/dec instructions that are atomic vs an interrupt. |
| * However, the code must first determine the differential location in a zone |
| * based on the processor number and then inc/dec the counter. There is no |
| * guarantee without disabling preemption that the processor will not change |
| * in between and therefore the atomicity vs. interrupt cannot be exploited |
| * in a useful way here. |
| */ |
| void __inc_zone_state(struct zone *zone, enum zone_stat_item item) |
| { |
| struct per_cpu_pageset __percpu *pcp = zone->pageset; |
| s8 __percpu *p = pcp->vm_stat_diff + item; |
| s8 v, t; |
| |
| v = __this_cpu_inc_return(*p); |
| t = __this_cpu_read(pcp->stat_threshold); |
| if (unlikely(v > t)) { |
| s8 overstep = t >> 1; |
| |
| zone_page_state_add(v + overstep, zone, item); |
| __this_cpu_write(*p, -overstep); |
| } |
| } |
| |
| void __inc_zone_page_state(struct page *page, enum zone_stat_item item) |
| { |
| __inc_zone_state(page_zone(page), item); |
| } |
| EXPORT_SYMBOL(__inc_zone_page_state); |
| |
| void __dec_zone_state(struct zone *zone, enum zone_stat_item item) |
| { |
| struct per_cpu_pageset __percpu *pcp = zone->pageset; |
| s8 __percpu *p = pcp->vm_stat_diff + item; |
| s8 v, t; |
| |
| v = __this_cpu_dec_return(*p); |
| t = __this_cpu_read(pcp->stat_threshold); |
| if (unlikely(v < - t)) { |
| s8 overstep = t >> 1; |
| |
| zone_page_state_add(v - overstep, zone, item); |
| __this_cpu_write(*p, overstep); |
| } |
| } |
| |
| 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); |
| |
| #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_state(struct zone *zone, |
| enum zone_stat_item item, int delta, int overstep_mode) |
| { |
| struct per_cpu_pageset __percpu *pcp = zone->pageset; |
| 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 (n > t || 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, |
| int delta) |
| { |
| mod_state(zone, item, delta, 0); |
| } |
| EXPORT_SYMBOL(mod_zone_page_state); |
| |
| void inc_zone_state(struct zone *zone, enum zone_stat_item item) |
| { |
| mod_state(zone, item, 1, 1); |
| } |
| |
| void inc_zone_page_state(struct page *page, enum zone_stat_item item) |
| { |
| mod_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_state(page_zone(page), item, -1, -1); |
| } |
| EXPORT_SYMBOL(dec_zone_page_state); |
| #else |
| /* |
| * Use interrupt disable to serialize counter updates |
| */ |
| void mod_zone_page_state(struct zone *zone, enum zone_stat_item item, |
| int 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_state(struct zone *zone, enum zone_stat_item item) |
| { |
| unsigned long flags; |
| |
| local_irq_save(flags); |
| __inc_zone_state(zone, item); |
| local_irq_restore(flags); |
| } |
| |
| 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); |
| #endif |
| |
| static inline void fold_diff(int *diff) |
| { |
| int i; |
| |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| if (diff[i]) |
| atomic_long_add(diff[i], &vm_stat[i]); |
| } |
| |
| /* |
| * 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. |
| */ |
| static void refresh_cpu_vm_stats(void) |
| { |
| struct zone *zone; |
| int i; |
| int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, }; |
| |
| for_each_populated_zone(zone) { |
| struct per_cpu_pageset __percpu *p = zone->pageset; |
| |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) { |
| int v; |
| |
| v = this_cpu_xchg(p->vm_stat_diff[i], 0); |
| if (v) { |
| |
| atomic_long_add(v, &zone->vm_stat[i]); |
| global_diff[i] += v; |
| #ifdef CONFIG_NUMA |
| /* 3 seconds idle till flush */ |
| __this_cpu_write(p->expire, 3); |
| #endif |
| } |
| } |
| cond_resched(); |
| #ifdef CONFIG_NUMA |
| /* |
| * 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(p->expire) || |
| !__this_cpu_read(p->pcp.count)) |
| continue; |
| |
| /* |
| * We never drain zones local to this processor. |
| */ |
| if (zone_to_nid(zone) == numa_node_id()) { |
| __this_cpu_write(p->expire, 0); |
| continue; |
| } |
| |
| |
| if (__this_cpu_dec_return(p->expire)) |
| continue; |
| |
| if (__this_cpu_read(p->pcp.count)) |
| drain_zone_pages(zone, this_cpu_ptr(&p->pcp)); |
| #endif |
| } |
| fold_diff(global_diff); |
| } |
| |
| /* |
| * 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 zone *zone; |
| int i; |
| int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, }; |
| |
| for_each_populated_zone(zone) { |
| struct per_cpu_pageset *p; |
| |
| p = per_cpu_ptr(zone->pageset, cpu); |
| |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| if (p->vm_stat_diff[i]) { |
| int v; |
| |
| v = p->vm_stat_diff[i]; |
| p->vm_stat_diff[i] = 0; |
| atomic_long_add(v, &zone->vm_stat[i]); |
| global_diff[i] += v; |
| } |
| } |
| |
| fold_diff(global_diff); |
| } |
| |
| /* |
| * this is only called if !populated_zone(zone), which implies no other users of |
| * pset->vm_stat_diff[] exsist. |
| */ |
| void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset) |
| { |
| int i; |
| |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| if (pset->vm_stat_diff[i]) { |
| int v = pset->vm_stat_diff[i]; |
| pset->vm_stat_diff[i] = 0; |
| atomic_long_add(v, &zone->vm_stat[i]); |
| atomic_long_add(v, &vm_stat[i]); |
| } |
| } |
| #endif |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * zonelist = the list of zones passed to the allocator |
| * z = the zone from which the allocation occurred. |
| * |
| * Must be called with interrupts disabled. |
| * |
| * When __GFP_OTHER_NODE is set assume the node of the preferred |
| * zone is the local node. This is useful for daemons who allocate |
| * memory on behalf of other processes. |
| */ |
| void zone_statistics(struct zone *preferred_zone, struct zone *z, gfp_t flags) |
| { |
| if (z->zone_pgdat == preferred_zone->zone_pgdat) { |
| __inc_zone_state(z, NUMA_HIT); |
| } else { |
| __inc_zone_state(z, NUMA_MISS); |
| __inc_zone_state(preferred_zone, NUMA_FOREIGN); |
| } |
| if (z->node == ((flags & __GFP_OTHER_NODE) ? |
| preferred_zone->node : numa_node_id())) |
| __inc_zone_state(z, NUMA_LOCAL); |
| else |
| __inc_zone_state(z, NUMA_OTHER); |
| } |
| #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 (!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); |
| } |
| |
| /* 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_COMPACTION) |
| #include <linux/proc_fs.h> |
| #include <linux/seq_file.h> |
| |
| static char * const migratetype_names[MIGRATE_TYPES] = { |
| "Unmovable", |
| "Reclaimable", |
| "Movable", |
| "Reserve", |
| #ifdef CONFIG_CMA |
| "CMA", |
| #endif |
| #ifdef CONFIG_MEMORY_ISOLATION |
| "Isolate", |
| #endif |
| }; |
| |
| 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 all the zones in a node and print using a callback */ |
| static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat, |
| 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 (!populated_zone(zone)) |
| continue; |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| print(m, pgdat, zone); |
| spin_unlock_irqrestore(&zone->lock, flags); |
| } |
| } |
| #endif |
| |
| #if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || defined(CONFIG_NUMA) |
| #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[] = { |
| /* Zoned VM counters */ |
| "nr_free_pages", |
| "nr_alloc_batch", |
| "nr_inactive_anon", |
| "nr_active_anon", |
| "nr_inactive_file", |
| "nr_active_file", |
| "nr_unevictable", |
| "nr_mlock", |
| "nr_anon_pages", |
| "nr_mapped", |
| "nr_file_pages", |
| "nr_dirty", |
| "nr_writeback", |
| "nr_slab_reclaimable", |
| "nr_slab_unreclaimable", |
| "nr_page_table_pages", |
| "nr_kernel_stack", |
| "nr_unstable", |
| "nr_bounce", |
| "nr_vmscan_write", |
| "nr_vmscan_immediate_reclaim", |
| "nr_writeback_temp", |
| "nr_isolated_anon", |
| "nr_isolated_file", |
| "nr_shmem", |
| "nr_dirtied", |
| "nr_written", |
| "nr_pages_scanned", |
| |
| #ifdef CONFIG_NUMA |
| "numa_hit", |
| "numa_miss", |
| "numa_foreign", |
| "numa_interleave", |
| "numa_local", |
| "numa_other", |
| #endif |
| "workingset_refault", |
| "workingset_activate", |
| "workingset_nodereclaim", |
| "nr_anon_transparent_hugepages", |
| "nr_free_cma", |
| "nr_dirty_threshold", |
| "nr_dirty_background_threshold", |
| |
| #ifdef CONFIG_VM_EVENT_COUNTERS |
| "pgpgin", |
| "pgpgout", |
| "pswpin", |
| "pswpout", |
| |
| TEXTS_FOR_ZONES("pgalloc") |
| |
| "pgfree", |
| "pgactivate", |
| "pgdeactivate", |
| |
| "pgfault", |
| "pgmajfault", |
| |
| TEXTS_FOR_ZONES("pgrefill") |
| TEXTS_FOR_ZONES("pgsteal_kswapd") |
| TEXTS_FOR_ZONES("pgsteal_direct") |
| TEXTS_FOR_ZONES("pgscan_kswapd") |
| TEXTS_FOR_ZONES("pgscan_direct") |
| "pgscan_direct_throttle", |
| |
| #ifdef CONFIG_NUMA |
| "zone_reclaim_failed", |
| #endif |
| "pginodesteal", |
| "slabs_scanned", |
| "kswapd_inodesteal", |
| "kswapd_low_wmark_hit_quickly", |
| "kswapd_high_wmark_hit_quickly", |
| "pageoutrun", |
| "allocstall", |
| |
| "pgrotated", |
| |
| "drop_pagecache", |
| "drop_slab", |
| |
| #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", |
| #endif |
| #ifdef CONFIG_COMPACTION |
| "compact_migrate_scanned", |
| "compact_free_scanned", |
| "compact_isolated", |
| "compact_stall", |
| "compact_fail", |
| "compact_success", |
| #endif |
| |
| #ifdef CONFIG_HUGETLB_PAGE |
| "htlb_buddy_alloc_success", |
| "htlb_buddy_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_collapse_alloc", |
| "thp_collapse_alloc_failed", |
| "thp_split", |
| "thp_zero_page_alloc", |
| "thp_zero_page_alloc_failed", |
| #endif |
| #ifdef CONFIG_DEBUG_TLBFLUSH |
| #ifdef CONFIG_SMP |
| "nr_tlb_remote_flush", |
| "nr_tlb_remote_flush_received", |
| #endif /* CONFIG_SMP */ |
| "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 |
| #endif /* CONFIG_VM_EVENTS_COUNTERS */ |
| }; |
| #endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA */ |
| |
| |
| #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, 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; |
| |
| area = &(zone->free_area[order]); |
| |
| list_for_each(curr, &area->free_list[mtype]) |
| freecount++; |
| seq_printf(m, "%6lu ", freecount); |
| } |
| seq_putc(m, '\n'); |
| } |
| } |
| |
| /* Print out the free pages at each order for each migatetype */ |
| static int 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, pagetypeinfo_showfree_print); |
| |
| return 0; |
| } |
| |
| 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; |
| |
| if (!pfn_valid(pfn)) |
| continue; |
| |
| page = pfn_to_page(pfn); |
| |
| /* Watch for unexpected holes punched in the memmap */ |
| if (!memmap_valid_within(pfn, 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 free pages at each order for each migratetype */ |
| static int 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, pagetypeinfo_showblockcount_print); |
| |
| return 0; |
| } |
| |
| /* |
| * 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); |
| |
| return 0; |
| } |
| |
| static const struct seq_operations fragmentation_op = { |
| .start = frag_start, |
| .next = frag_next, |
| .stop = frag_stop, |
| .show = frag_show, |
| }; |
| |
| static int fragmentation_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &fragmentation_op); |
| } |
| |
| static const struct file_operations fragmentation_file_operations = { |
| .open = fragmentation_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| static const struct seq_operations pagetypeinfo_op = { |
| .start = frag_start, |
| .next = frag_next, |
| .stop = frag_stop, |
| .show = pagetypeinfo_show, |
| }; |
| |
| static int pagetypeinfo_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &pagetypeinfo_op); |
| } |
| |
| static const struct file_operations pagetypeinfo_file_ops = { |
| .open = pagetypeinfo_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| 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); |
| seq_printf(m, |
| "\n pages free %lu" |
| "\n min %lu" |
| "\n low %lu" |
| "\n high %lu" |
| "\n scanned %lu" |
| "\n spanned %lu" |
| "\n present %lu" |
| "\n managed %lu", |
| zone_page_state(zone, NR_FREE_PAGES), |
| min_wmark_pages(zone), |
| low_wmark_pages(zone), |
| high_wmark_pages(zone), |
| zone_page_state(zone, NR_PAGES_SCANNED), |
| zone->spanned_pages, |
| zone->present_pages, |
| zone->managed_pages); |
| |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| seq_printf(m, "\n %-12s %lu", vmstat_text[i], |
| zone_page_state(zone, i)); |
| |
| 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_printf(m, |
| ")" |
| "\n pagesets"); |
| for_each_online_cpu(i) { |
| struct per_cpu_pageset *pageset; |
| |
| pageset = per_cpu_ptr(zone->pageset, i); |
| seq_printf(m, |
| "\n cpu: %i" |
| "\n count: %i" |
| "\n high: %i" |
| "\n batch: %i", |
| i, |
| pageset->pcp.count, |
| pageset->pcp.high, |
| pageset->pcp.batch); |
| #ifdef CONFIG_SMP |
| seq_printf(m, "\n vm stats threshold: %d", |
| pageset->stat_threshold); |
| #endif |
| } |
| seq_printf(m, |
| "\n all_unreclaimable: %u" |
| "\n start_pfn: %lu" |
| "\n inactive_ratio: %u", |
| !zone_reclaimable(zone), |
| zone->zone_start_pfn, |
| zone->inactive_ratio); |
| seq_putc(m, '\n'); |
| } |
| |
| /* |
| * Output information about zones in @pgdat. |
| */ |
| static int zoneinfo_show(struct seq_file *m, void *arg) |
| { |
| pg_data_t *pgdat = (pg_data_t *)arg; |
| walk_zones_in_node(m, pgdat, 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, |
| }; |
| |
| static int zoneinfo_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &zoneinfo_op); |
| } |
| |
| static const struct file_operations proc_zoneinfo_file_operations = { |
| .open = zoneinfo_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| enum writeback_stat_item { |
| NR_DIRTY_THRESHOLD, |
| NR_DIRTY_BG_THRESHOLD, |
| NR_VM_WRITEBACK_STAT_ITEMS, |
| }; |
| |
| static void *vmstat_start(struct seq_file *m, loff_t *pos) |
| { |
| unsigned long *v; |
| int i, stat_items_size; |
| |
| if (*pos >= ARRAY_SIZE(vmstat_text)) |
| return NULL; |
| stat_items_size = NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) + |
| NR_VM_WRITEBACK_STAT_ITEMS * sizeof(unsigned long); |
| |
| #ifdef CONFIG_VM_EVENT_COUNTERS |
| stat_items_size += sizeof(struct vm_event_state); |
| #endif |
| |
| v = kmalloc(stat_items_size, GFP_KERNEL); |
| m->private = v; |
| if (!v) |
| return ERR_PTR(-ENOMEM); |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| v[i] = global_page_state(i); |
| v += NR_VM_ZONE_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 >= ARRAY_SIZE(vmstat_text)) |
| 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_printf(m, "%s %lu\n", vmstat_text[off], *l); |
| 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, |
| }; |
| |
| static int vmstat_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &vmstat_op); |
| } |
| |
| static const struct file_operations proc_vmstat_file_operations = { |
| .open = vmstat_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| #endif /* CONFIG_PROC_FS */ |
| |
| #ifdef CONFIG_SMP |
| static DEFINE_PER_CPU(struct delayed_work, vmstat_work); |
| int sysctl_stat_interval __read_mostly = HZ; |
| |
| static void vmstat_update(struct work_struct *w) |
| { |
| refresh_cpu_vm_stats(); |
| schedule_delayed_work(this_cpu_ptr(&vmstat_work), |
| round_jiffies_relative(sysctl_stat_interval)); |
| } |
| |
| static void start_cpu_timer(int cpu) |
| { |
| struct delayed_work *work = &per_cpu(vmstat_work, cpu); |
| |
| INIT_DEFERRABLE_WORK(work, vmstat_update); |
| schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu)); |
| } |
| |
| static void vmstat_cpu_dead(int node) |
| { |
| int cpu; |
| |
| get_online_cpus(); |
| for_each_online_cpu(cpu) |
| if (cpu_to_node(cpu) == node) |
| goto end; |
| |
| node_clear_state(node, N_CPU); |
| end: |
| put_online_cpus(); |
| } |
| |
| /* |
| * Use the cpu notifier to insure that the thresholds are recalculated |
| * when necessary. |
| */ |
| static int vmstat_cpuup_callback(struct notifier_block *nfb, |
| unsigned long action, |
| void *hcpu) |
| { |
| long cpu = (long)hcpu; |
| |
| switch (action) { |
| case CPU_ONLINE: |
| case CPU_ONLINE_FROZEN: |
| refresh_zone_stat_thresholds(); |
| start_cpu_timer(cpu); |
| node_set_state(cpu_to_node(cpu), N_CPU); |
| break; |
| case CPU_DOWN_PREPARE: |
| case CPU_DOWN_PREPARE_FROZEN: |
| cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu)); |
| per_cpu(vmstat_work, cpu).work.func = NULL; |
| break; |
| case CPU_DOWN_FAILED: |
| case CPU_DOWN_FAILED_FROZEN: |
| start_cpu_timer(cpu); |
| break; |
| case CPU_DEAD: |
| case CPU_DEAD_FROZEN: |
| refresh_zone_stat_thresholds(); |
| vmstat_cpu_dead(cpu_to_node(cpu)); |
| break; |
| default: |
| break; |
| } |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block vmstat_notifier = |
| { &vmstat_cpuup_callback, NULL, 0 }; |
| #endif |
| |
| static int __init setup_vmstat(void) |
| { |
| #ifdef CONFIG_SMP |
| int cpu; |
| |
| cpu_notifier_register_begin(); |
| __register_cpu_notifier(&vmstat_notifier); |
| |
| for_each_online_cpu(cpu) { |
| start_cpu_timer(cpu); |
| node_set_state(cpu_to_node(cpu), N_CPU); |
| } |
| cpu_notifier_register_done(); |
| #endif |
| #ifdef CONFIG_PROC_FS |
| proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations); |
| proc_create("pagetypeinfo", S_IRUGO, NULL, &pagetypeinfo_file_ops); |
| proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations); |
| proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations); |
| #endif |
| return 0; |
| } |
| module_init(setup_vmstat) |
| |
| #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION) |
| #include <linux/debugfs.h> |
| |
| |
| /* |
| * 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, unusable_show_print); |
| |
| return 0; |
| } |
| |
| static const struct seq_operations unusable_op = { |
| .start = frag_start, |
| .next = frag_next, |
| .stop = frag_stop, |
| .show = unusable_show, |
| }; |
| |
| static int unusable_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &unusable_op); |
| } |
| |
| static const struct file_operations unusable_file_ops = { |
| .open = unusable_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| 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, extfrag_show_print); |
| |
| return 0; |
| } |
| |
| static const struct seq_operations extfrag_op = { |
| .start = frag_start, |
| .next = frag_next, |
| .stop = frag_stop, |
| .show = extfrag_show, |
| }; |
| |
| static int extfrag_open(struct inode *inode, struct file *file) |
| { |
| return seq_open(file, &extfrag_op); |
| } |
| |
| static const struct file_operations extfrag_file_ops = { |
| .open = extfrag_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release, |
| }; |
| |
| static int __init extfrag_debug_init(void) |
| { |
| struct dentry *extfrag_debug_root; |
| |
| extfrag_debug_root = debugfs_create_dir("extfrag", NULL); |
| if (!extfrag_debug_root) |
| return -ENOMEM; |
| |
| if (!debugfs_create_file("unusable_index", 0444, |
| extfrag_debug_root, NULL, &unusable_file_ops)) |
| goto fail; |
| |
| if (!debugfs_create_file("extfrag_index", 0444, |
| extfrag_debug_root, NULL, &extfrag_file_ops)) |
| goto fail; |
| |
| return 0; |
| fail: |
| debugfs_remove_recursive(extfrag_debug_root); |
| return -ENOMEM; |
| } |
| |
| module_init(extfrag_debug_init); |
| #endif |