root/tools/mm/slabinfo.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Slabinfo: Tool to get reports about slabs
 *
 * (C) 2007 sgi, Christoph Lameter
 * (C) 2011 Linux Foundation, Christoph Lameter
 *
 * Compile with:
 *
 * gcc -o slabinfo slabinfo.c
 */
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <dirent.h>
#include <strings.h>
#include <string.h>
#include <unistd.h>
#include <stdarg.h>
#include <getopt.h>
#include <regex.h>
#include <errno.h>

#define MAX_SLABS 2000
#define MAX_ALIASES 500
#define MAX_NODES 1024

struct slabinfo {
        char *name;
        int alias;
        int refs;
        int aliases, align, cache_dma, cpu_slabs, destroy_by_rcu;
        unsigned int hwcache_align, object_size, objs_per_slab;
        unsigned int sanity_checks, slab_size, store_user, trace;
        int order, poison, reclaim_account, red_zone;
        unsigned long partial, objects, slabs, objects_partial, objects_total;
        unsigned long alloc_fastpath, alloc_slowpath;
        unsigned long free_fastpath, free_slowpath;
        unsigned long free_frozen, free_add_partial, free_remove_partial;
        unsigned long alloc_from_partial, alloc_slab, free_slab, alloc_refill;
        unsigned long cpuslab_flush, deactivate_full, deactivate_empty;
        unsigned long deactivate_to_head, deactivate_to_tail;
        unsigned long deactivate_remote_frees, order_fallback;
        unsigned long cmpxchg_double_cpu_fail, cmpxchg_double_fail;
        unsigned long alloc_node_mismatch, deactivate_bypass;
        unsigned long cpu_partial_alloc, cpu_partial_free;
        int numa[MAX_NODES];
        int numa_partial[MAX_NODES];
} slabinfo[MAX_SLABS];

struct aliasinfo {
        char *name;
        char *ref;
        struct slabinfo *slab;
} aliasinfo[MAX_ALIASES];

int slabs;
int actual_slabs;
int aliases;
int alias_targets;
int highest_node;

char buffer[4096];

int show_empty;
int show_report;
int show_alias;
int show_slab;
int skip_zero = 1;
int show_numa;
int show_track;
int show_first_alias;
int validate;
int shrink;
int show_inverted;
int show_single_ref;
int show_totals;
int sort_size;
int sort_active;
int set_debug;
int show_ops;
int sort_partial;
int show_activity;
int output_lines = -1;
int sort_loss;
int extended_totals;
int show_bytes;
int unreclaim_only;

/* Debug options */
int sanity;
int redzone;
int poison;
int tracking;
int tracing;

int page_size;

regex_t pattern;

static void fatal(const char *x, ...)
{
        va_list ap;

        va_start(ap, x);
        vfprintf(stderr, x, ap);
        va_end(ap);
        exit(EXIT_FAILURE);
}

static void usage(void)
{
        printf("slabinfo 4/15/2011. (c) 2007 sgi/(c) 2011 Linux Foundation.\n\n"
                "slabinfo [-aABDefhilLnoPrsStTUvXz1] [N=K] [-dafzput] [slab-regexp]\n"
                "-a|--aliases           Show aliases\n"
                "-A|--activity          Most active slabs first\n"
                "-B|--Bytes             Show size in bytes\n"
                "-D|--display-active    Switch line format to activity\n"
                "-e|--empty             Show empty slabs\n"
                "-f|--first-alias       Show first alias\n"
                "-h|--help              Show usage information\n"
                "-i|--inverted          Inverted list\n"
                "-l|--slabs             Show slabs\n"
                "-L|--Loss              Sort by loss\n"
                "-n|--numa              Show NUMA information\n"
                "-N|--lines=K           Show the first K slabs\n"
                "-o|--ops               Show kmem_cache_ops\n"
                "-P|--partial           Sort by number of partial slabs\n"
                "-r|--report            Detailed report on single slabs\n"
                "-s|--shrink            Shrink slabs\n"
                "-S|--Size              Sort by size\n"
                "-t|--tracking          Show alloc/free information\n"
                "-T|--Totals            Show summary information\n"
                "-U|--Unreclaim         Show unreclaimable slabs only\n"
                "-v|--validate          Validate slabs\n"
                "-X|--Xtotals           Show extended summary information\n"
                "-z|--zero              Include empty slabs\n"
                "-1|--1ref              Single reference\n"

                "\n"
                "-d  | --debug          Switch off all debug options\n"
                "-da | --debug=a        Switch on all debug options (--debug=FZPU)\n"

                "\n"
                "-d[afzput] | --debug=[afzput]\n"
                "    f | F              Sanity Checks (SLAB_CONSISTENCY_CHECKS)\n"
                "    z | Z              Redzoning\n"
                "    p | P              Poisoning\n"
                "    u | U              Tracking\n"
                "    t | T              Tracing\n"

                "\nSorting options (--Loss, --Size, --Partial) are mutually exclusive\n"
        );
}

static unsigned long read_obj(const char *name)
{
        size_t len;
        FILE *f = fopen(name, "r");

        if (!f) {
                buffer[0] = 0;
                if (errno == EACCES)
                        fatal("%s, Try using superuser\n", strerror(errno));
        } else {
                if (!fgets(buffer, sizeof(buffer), f))
                        buffer[0] = 0;
                fclose(f);
                len = strlen(buffer);

                if (len > 0 && buffer[len - 1] == '\n')
                        buffer[len - 1] = 0;
        }
        return strlen(buffer);
}


/*
 * Get the contents of an attribute
 */
static unsigned long get_obj(const char *name)
{
        if (!read_obj(name))
                return 0;

        return atol(buffer);
}

static unsigned long get_obj_and_str(const char *name, char **x)
{
        unsigned long result = 0;
        char *p;

        *x = NULL;

        if (!read_obj(name)) {
                x = NULL;
                return 0;
        }
        result = strtoul(buffer, &p, 10);
        while (*p == ' ')
                p++;
        if (*p)
                *x = strdup(p);
        return result;
}

static void set_obj(struct slabinfo *s, const char *name, int n)
{
        char x[100];
        FILE *f;

        snprintf(x, 100, "%s/%s", s->name, name);
        f = fopen(x, "w");
        if (!f)
                fatal("Cannot write to %s\n", x);

        fprintf(f, "%d\n", n);
        fclose(f);
}

static unsigned long read_slab_obj(struct slabinfo *s, const char *name)
{
        char x[100];
        FILE *f;
        size_t l;

        snprintf(x, 100, "%s/%s", s->name, name);
        f = fopen(x, "r");
        if (!f) {
                buffer[0] = 0;
                l = 0;
        } else {
                l = fread(buffer, 1, sizeof(buffer), f);
                buffer[l] = 0;
                fclose(f);
        }
        return l;
}

static unsigned long read_debug_slab_obj(struct slabinfo *s, const char *name)
{
        char x[128];
        FILE *f;
        size_t l;

        snprintf(x, 128, "/sys/kernel/debug/slab/%s/%s", s->name, name);
        f = fopen(x, "r");
        if (!f) {
                buffer[0] = 0;
                l = 0;
        } else {
                l = fread(buffer, 1, sizeof(buffer), f);
                buffer[l] = 0;
                fclose(f);
        }
        return l;
}

/*
 * Put a size string together
 */
static int store_size(char *buffer, unsigned long value)
{
        unsigned long divisor = 1;
        char trailer = 0;
        int n;

        if (!show_bytes) {
                if (value > 1000000000UL) {
                        divisor = 100000000UL;
                        trailer = 'G';
                } else if (value > 1000000UL) {
                        divisor = 100000UL;
                        trailer = 'M';
                } else if (value > 1000UL) {
                        divisor = 100;
                        trailer = 'K';
                }
        }

        value /= divisor;
        n = sprintf(buffer, "%ld",value);
        if (trailer) {
                buffer[n] = trailer;
                n++;
                buffer[n] = 0;
        }
        if (divisor != 1) {
                memmove(buffer + n - 2, buffer + n - 3, 4);
                buffer[n-2] = '.';
                n++;
        }
        return n;
}

static void decode_numa_list(int *numa, char *t)
{
        int node;
        int nr;

        memset(numa, 0, MAX_NODES * sizeof(int));

        if (!t)
                return;

        while (*t == 'N') {
                t++;
                node = strtoul(t, &t, 10);
                if (*t == '=') {
                        t++;
                        nr = strtoul(t, &t, 10);
                        numa[node] = nr;
                        if (node > highest_node)
                                highest_node = node;
                }
                while (*t == ' ')
                        t++;
        }
}

static void slab_validate(struct slabinfo *s)
{
        if (strcmp(s->name, "*") == 0)
                return;

        set_obj(s, "validate", 1);
}

static void slab_shrink(struct slabinfo *s)
{
        if (strcmp(s->name, "*") == 0)
                return;

        set_obj(s, "shrink", 1);
}

int line = 0;

static void first_line(void)
{
        if (show_activity)
                printf("Name                   Objects      Alloc       Free"
                        "   %%Fast Fallb O CmpX   UL\n");
        else
                printf("Name                   Objects Objsize           %s "
                        "Slabs/Part/Cpu  O/S O %%Fr %%Ef Flg\n",
                        sort_loss ? " Loss" : "Space");
}

/*
 * Find the shortest alias of a slab
 */
static struct aliasinfo *find_one_alias(struct slabinfo *find)
{
        struct aliasinfo *a;
        struct aliasinfo *best = NULL;

        for(a = aliasinfo;a < aliasinfo + aliases; a++) {
                if (a->slab == find &&
                        (!best || strlen(best->name) < strlen(a->name))) {
                                best = a;
                                if (strncmp(a->name,"kmall", 5) == 0)
                                        return best;
                        }
        }
        return best;
}

static unsigned long slab_size(struct slabinfo *s)
{
        return  s->slabs * (page_size << s->order);
}

static unsigned long slab_activity(struct slabinfo *s)
{
        return  s->alloc_fastpath + s->free_fastpath +
                s->alloc_slowpath + s->free_slowpath;
}

static unsigned long slab_waste(struct slabinfo *s)
{
        return  slab_size(s) - s->objects * s->object_size;
}

static void slab_numa(struct slabinfo *s, int mode)
{
        int node;

        if (strcmp(s->name, "*") == 0)
                return;

        if (!highest_node) {
                printf("\n%s: No NUMA information available.\n", s->name);
                return;
        }

        if (skip_zero && !s->slabs)
                return;

        if (!line) {
                printf("\n%-21s:", mode ? "NUMA nodes" : "Slab");
                for(node = 0; node <= highest_node; node++)
                        printf(" %4d", node);
                printf("\n----------------------");
                for(node = 0; node <= highest_node; node++)
                        printf("-----");
                printf("\n");
        }
        printf("%-21s ", mode ? "All slabs" : s->name);
        for(node = 0; node <= highest_node; node++) {
                char b[20];

                store_size(b, s->numa[node]);
                printf(" %4s", b);
        }
        printf("\n");
        if (mode) {
                printf("%-21s ", "Partial slabs");
                for(node = 0; node <= highest_node; node++) {
                        char b[20];

                        store_size(b, s->numa_partial[node]);
                        printf(" %4s", b);
                }
                printf("\n");
        }
        line++;
}

static void show_tracking(struct slabinfo *s)
{
        printf("\n%s: Kernel object allocation\n", s->name);
        printf("-----------------------------------------------------------------------\n");
        if (read_debug_slab_obj(s, "alloc_traces"))
                printf("%s", buffer);
        else if (read_slab_obj(s, "alloc_calls"))
                printf("%s", buffer);
        else
                printf("No Data\n");

        printf("\n%s: Kernel object freeing\n", s->name);
        printf("------------------------------------------------------------------------\n");
        if (read_debug_slab_obj(s, "free_traces"))
                printf("%s", buffer);
        else if (read_slab_obj(s, "free_calls"))
                printf("%s", buffer);
        else
                printf("No Data\n");

}

static void ops(struct slabinfo *s)
{
        if (strcmp(s->name, "*") == 0)
                return;

        if (read_slab_obj(s, "ops")) {
                printf("\n%s: kmem_cache operations\n", s->name);
                printf("--------------------------------------------\n");
                printf("%s", buffer);
        } else
                printf("\n%s has no kmem_cache operations\n", s->name);
}

static const char *onoff(int x)
{
        if (x)
                return "On ";
        return "Off";
}

static void slab_stats(struct slabinfo *s)
{
        unsigned long total_alloc;
        unsigned long total_free;
        unsigned long total;

        if (!s->alloc_slab)
                return;

        total_alloc = s->alloc_fastpath + s->alloc_slowpath;
        total_free = s->free_fastpath + s->free_slowpath;

        if (!total_alloc)
                return;

        printf("\n");
        printf("Slab Perf Counter       Alloc     Free %%Al %%Fr\n");
        printf("--------------------------------------------------\n");
        printf("Fastpath             %8lu %8lu %3lu %3lu\n",
                s->alloc_fastpath, s->free_fastpath,
                s->alloc_fastpath * 100 / total_alloc,
                total_free ? s->free_fastpath * 100 / total_free : 0);
        printf("Slowpath             %8lu %8lu %3lu %3lu\n",
                total_alloc - s->alloc_fastpath, s->free_slowpath,
                (total_alloc - s->alloc_fastpath) * 100 / total_alloc,
                total_free ? s->free_slowpath * 100 / total_free : 0);
        printf("Page Alloc           %8lu %8lu %3lu %3lu\n",
                s->alloc_slab, s->free_slab,
                s->alloc_slab * 100 / total_alloc,
                total_free ? s->free_slab * 100 / total_free : 0);
        printf("Add partial          %8lu %8lu %3lu %3lu\n",
                s->deactivate_to_head + s->deactivate_to_tail,
                s->free_add_partial,
                (s->deactivate_to_head + s->deactivate_to_tail) * 100 / total_alloc,
                total_free ? s->free_add_partial * 100 / total_free : 0);
        printf("Remove partial       %8lu %8lu %3lu %3lu\n",
                s->alloc_from_partial, s->free_remove_partial,
                s->alloc_from_partial * 100 / total_alloc,
                total_free ? s->free_remove_partial * 100 / total_free : 0);

        printf("Cpu partial list     %8lu %8lu %3lu %3lu\n",
                s->cpu_partial_alloc, s->cpu_partial_free,
                s->cpu_partial_alloc * 100 / total_alloc,
                total_free ? s->cpu_partial_free * 100 / total_free : 0);

        printf("RemoteObj/SlabFrozen %8lu %8lu %3lu %3lu\n",
                s->deactivate_remote_frees, s->free_frozen,
                s->deactivate_remote_frees * 100 / total_alloc,
                total_free ? s->free_frozen * 100 / total_free : 0);

        printf("Total                %8lu %8lu\n\n", total_alloc, total_free);

        if (s->cpuslab_flush)
                printf("Flushes %8lu\n", s->cpuslab_flush);

        total = s->deactivate_full + s->deactivate_empty +
                        s->deactivate_to_head + s->deactivate_to_tail + s->deactivate_bypass;

        if (total) {
                printf("\nSlab Deactivation             Occurrences %%\n");
                printf("-------------------------------------------------\n");
                printf("Slab full                     %7lu  %3lu%%\n",
                        s->deactivate_full, (s->deactivate_full * 100) / total);
                printf("Slab empty                    %7lu  %3lu%%\n",
                        s->deactivate_empty, (s->deactivate_empty * 100) / total);
                printf("Moved to head of partial list %7lu  %3lu%%\n",
                        s->deactivate_to_head, (s->deactivate_to_head * 100) / total);
                printf("Moved to tail of partial list %7lu  %3lu%%\n",
                        s->deactivate_to_tail, (s->deactivate_to_tail * 100) / total);
                printf("Deactivation bypass           %7lu  %3lu%%\n",
                        s->deactivate_bypass, (s->deactivate_bypass * 100) / total);
                printf("Refilled from foreign frees   %7lu  %3lu%%\n",
                        s->alloc_refill, (s->alloc_refill * 100) / total);
                printf("Node mismatch                 %7lu  %3lu%%\n",
                        s->alloc_node_mismatch, (s->alloc_node_mismatch * 100) / total);
        }

        if (s->cmpxchg_double_fail || s->cmpxchg_double_cpu_fail) {
                printf("\nCmpxchg_double Looping\n------------------------\n");
                printf("Locked Cmpxchg Double redos   %lu\nUnlocked Cmpxchg Double redos %lu\n",
                        s->cmpxchg_double_fail, s->cmpxchg_double_cpu_fail);
        }
}

static void report(struct slabinfo *s)
{
        if (strcmp(s->name, "*") == 0)
                return;

        printf("\nSlabcache: %-15s  Aliases: %2d Order : %2d Objects: %lu\n",
                s->name, s->aliases, s->order, s->objects);
        if (s->hwcache_align)
                printf("** Hardware cacheline aligned\n");
        if (s->cache_dma)
                printf("** Memory is allocated in a special DMA zone\n");
        if (s->destroy_by_rcu)
                printf("** Slabs are destroyed via RCU\n");
        if (s->reclaim_account)
                printf("** Reclaim accounting active\n");

        printf("\nSizes (bytes)     Slabs              Debug                Memory\n");
        printf("------------------------------------------------------------------------\n");
        printf("Object : %7d  Total  : %7ld   Sanity Checks : %s  Total: %7ld\n",
                        s->object_size, s->slabs, onoff(s->sanity_checks),
                        s->slabs * (page_size << s->order));
        printf("SlabObj: %7d  Full   : %7ld   Redzoning     : %s  Used : %7ld\n",
                        s->slab_size, s->slabs - s->partial - s->cpu_slabs,
                        onoff(s->red_zone), s->objects * s->object_size);
        printf("SlabSiz: %7d  Partial: %7ld   Poisoning     : %s  Loss : %7ld\n",
                        page_size << s->order, s->partial, onoff(s->poison),
                        s->slabs * (page_size << s->order) - s->objects * s->object_size);
        printf("Loss   : %7d  CpuSlab: %7d   Tracking      : %s  Lalig: %7ld\n",
                        s->slab_size - s->object_size, s->cpu_slabs, onoff(s->store_user),
                        (s->slab_size - s->object_size) * s->objects);
        printf("Align  : %7d  Objects: %7d   Tracing       : %s  Lpadd: %7ld\n",
                        s->align, s->objs_per_slab, onoff(s->trace),
                        ((page_size << s->order) - s->objs_per_slab * s->slab_size) *
                        s->slabs);

        ops(s);
        show_tracking(s);
        slab_numa(s, 1);
        slab_stats(s);
}

static void slabcache(struct slabinfo *s)
{
        char size_str[20];
        char dist_str[40];
        char flags[20];
        char *p = flags;

        if (strcmp(s->name, "*") == 0)
                return;

        if (unreclaim_only && s->reclaim_account)
                return;

        if (actual_slabs == 1) {
                report(s);
                return;
        }

        if (skip_zero && !show_empty && !s->slabs)
                return;

        if (show_empty && s->slabs)
                return;

        if (sort_loss == 0)
                store_size(size_str, slab_size(s));
        else
                store_size(size_str, slab_waste(s));
        snprintf(dist_str, 40, "%lu/%lu/%d", s->slabs - s->cpu_slabs,
                                                s->partial, s->cpu_slabs);

        if (!line++)
                first_line();

        if (s->aliases)
                *p++ = '*';
        if (s->cache_dma)
                *p++ = 'd';
        if (s->hwcache_align)
                *p++ = 'A';
        if (s->poison)
                *p++ = 'P';
        if (s->reclaim_account)
                *p++ = 'a';
        if (s->red_zone)
                *p++ = 'Z';
        if (s->sanity_checks)
                *p++ = 'F';
        if (s->store_user)
                *p++ = 'U';
        if (s->trace)
                *p++ = 'T';

        *p = 0;
        if (show_activity) {
                unsigned long total_alloc;
                unsigned long total_free;

                total_alloc = s->alloc_fastpath + s->alloc_slowpath;
                total_free = s->free_fastpath + s->free_slowpath;

                printf("%-21s %8ld %10ld %10ld %3ld %3ld %5ld %1d %4ld %4ld\n",
                        s->name, s->objects,
                        total_alloc, total_free,
                        total_alloc ? (s->alloc_fastpath * 100 / total_alloc) : 0,
                        total_free ? (s->free_fastpath * 100 / total_free) : 0,
                        s->order_fallback, s->order, s->cmpxchg_double_fail,
                        s->cmpxchg_double_cpu_fail);
        } else {
                printf("%-21s %8ld %7d %15s %14s %4d %1d %3ld %3ld %s\n",
                        s->name, s->objects, s->object_size, size_str, dist_str,
                        s->objs_per_slab, s->order,
                        s->slabs ? (s->partial * 100) / s->slabs : 100,
                        s->slabs ? (s->objects * s->object_size * 100) /
                                (s->slabs * (page_size << s->order)) : 100,
                        flags);
        }
}

/*
 * Analyze debug options. Return false if something is amiss.
 */
static int debug_opt_scan(char *opt)
{
        if (!opt || !opt[0] || strcmp(opt, "-") == 0)
                return 1;

        if (strcasecmp(opt, "a") == 0) {
                sanity = 1;
                poison = 1;
                redzone = 1;
                tracking = 1;
                return 1;
        }

        for ( ; *opt; opt++)
                switch (*opt) {
                case 'F' : case 'f':
                        if (sanity)
                                return 0;
                        sanity = 1;
                        break;
                case 'P' : case 'p':
                        if (poison)
                                return 0;
                        poison = 1;
                        break;

                case 'Z' : case 'z':
                        if (redzone)
                                return 0;
                        redzone = 1;
                        break;

                case 'U' : case 'u':
                        if (tracking)
                                return 0;
                        tracking = 1;
                        break;

                case 'T' : case 't':
                        if (tracing)
                                return 0;
                        tracing = 1;
                        break;
                default:
                        return 0;
                }
        return 1;
}

static int slab_empty(struct slabinfo *s)
{
        if (s->objects > 0)
                return 0;

        /*
         * We may still have slabs even if there are no objects. Shrinking will
         * remove them.
         */
        if (s->slabs != 0)
                set_obj(s, "shrink", 1);

        return 1;
}

static void slab_debug(struct slabinfo *s)
{
        if (strcmp(s->name, "*") == 0)
                return;

        if (sanity && !s->sanity_checks) {
                set_obj(s, "sanity_checks", 1);
        }
        if (!sanity && s->sanity_checks) {
                if (slab_empty(s))
                        set_obj(s, "sanity_checks", 0);
                else
                        fprintf(stderr, "%s not empty cannot disable sanity checks\n", s->name);
        }
        if (redzone && !s->red_zone) {
                if (slab_empty(s))
                        set_obj(s, "red_zone", 1);
                else
                        fprintf(stderr, "%s not empty cannot enable redzoning\n", s->name);
        }
        if (!redzone && s->red_zone) {
                if (slab_empty(s))
                        set_obj(s, "red_zone", 0);
                else
                        fprintf(stderr, "%s not empty cannot disable redzoning\n", s->name);
        }
        if (poison && !s->poison) {
                if (slab_empty(s))
                        set_obj(s, "poison", 1);
                else
                        fprintf(stderr, "%s not empty cannot enable poisoning\n", s->name);
        }
        if (!poison && s->poison) {
                if (slab_empty(s))
                        set_obj(s, "poison", 0);
                else
                        fprintf(stderr, "%s not empty cannot disable poisoning\n", s->name);
        }
        if (tracking && !s->store_user) {
                if (slab_empty(s))
                        set_obj(s, "store_user", 1);
                else
                        fprintf(stderr, "%s not empty cannot enable tracking\n", s->name);
        }
        if (!tracking && s->store_user) {
                if (slab_empty(s))
                        set_obj(s, "store_user", 0);
                else
                        fprintf(stderr, "%s not empty cannot disable tracking\n", s->name);
        }
        if (tracing && !s->trace) {
                if (slabs == 1)
                        set_obj(s, "trace", 1);
                else
                        fprintf(stderr, "%s can only enable trace for one slab at a time\n", s->name);
        }
        if (!tracing && s->trace)
                set_obj(s, "trace", 1);
}

static void totals(void)
{
        struct slabinfo *s;

        int used_slabs = 0;
        char b1[20], b2[20], b3[20], b4[20];
        unsigned long long max = 1ULL << 63;

        /* Object size */
        unsigned long long min_objsize = max, max_objsize = 0, avg_objsize;

        /* Number of partial slabs in a slabcache */
        unsigned long long min_partial = max, max_partial = 0,
                                avg_partial, total_partial = 0;

        /* Number of slabs in a slab cache */
        unsigned long long min_slabs = max, max_slabs = 0,
                                avg_slabs, total_slabs = 0;

        /* Size of the whole slab */
        unsigned long long min_size = max, max_size = 0,
                                avg_size, total_size = 0;

        /* Bytes used for object storage in a slab */
        unsigned long long min_used = max, max_used = 0,
                                avg_used, total_used = 0;

        /* Waste: Bytes used for alignment and padding */
        unsigned long long min_waste = max, max_waste = 0,
                                avg_waste, total_waste = 0;
        /* Number of objects in a slab */
        unsigned long long min_objects = max, max_objects = 0,
                                avg_objects, total_objects = 0;
        /* Waste per object */
        unsigned long long min_objwaste = max,
                                max_objwaste = 0, avg_objwaste,
                                total_objwaste = 0;

        /* Memory per object */
        unsigned long long min_memobj = max,
                                max_memobj = 0, avg_memobj,
                                total_objsize = 0;

        /* Percentage of partial slabs per slab */
        unsigned long min_ppart = 100, max_ppart = 0,
                                avg_ppart, total_ppart = 0;

        /* Number of objects in partial slabs */
        unsigned long min_partobj = max, max_partobj = 0,
                                avg_partobj, total_partobj = 0;

        /* Percentage of partial objects of all objects in a slab */
        unsigned long min_ppartobj = 100, max_ppartobj = 0,
                                avg_ppartobj, total_ppartobj = 0;


        for (s = slabinfo; s < slabinfo + slabs; s++) {
                unsigned long long size;
                unsigned long used;
                unsigned long long wasted;
                unsigned long long objwaste;
                unsigned long percentage_partial_slabs;
                unsigned long percentage_partial_objs;

                if (!s->slabs || !s->objects)
                        continue;

                used_slabs++;

                size = slab_size(s);
                used = s->objects * s->object_size;
                wasted = size - used;
                objwaste = s->slab_size - s->object_size;

                percentage_partial_slabs = s->partial * 100 / s->slabs;
                if (percentage_partial_slabs > 100)
                        percentage_partial_slabs = 100;

                percentage_partial_objs = s->objects_partial * 100
                                                        / s->objects;

                if (percentage_partial_objs > 100)
                        percentage_partial_objs = 100;

                if (s->object_size < min_objsize)
                        min_objsize = s->object_size;
                if (s->partial < min_partial)
                        min_partial = s->partial;
                if (s->slabs < min_slabs)
                        min_slabs = s->slabs;
                if (size < min_size)
                        min_size = size;
                if (wasted < min_waste)
                        min_waste = wasted;
                if (objwaste < min_objwaste)
                        min_objwaste = objwaste;
                if (s->objects < min_objects)
                        min_objects = s->objects;
                if (used < min_used)
                        min_used = used;
                if (s->objects_partial < min_partobj)
                        min_partobj = s->objects_partial;
                if (percentage_partial_slabs < min_ppart)
                        min_ppart = percentage_partial_slabs;
                if (percentage_partial_objs < min_ppartobj)
                        min_ppartobj = percentage_partial_objs;
                if (s->slab_size < min_memobj)
                        min_memobj = s->slab_size;

                if (s->object_size > max_objsize)
                        max_objsize = s->object_size;
                if (s->partial > max_partial)
                        max_partial = s->partial;
                if (s->slabs > max_slabs)
                        max_slabs = s->slabs;
                if (size > max_size)
                        max_size = size;
                if (wasted > max_waste)
                        max_waste = wasted;
                if (objwaste > max_objwaste)
                        max_objwaste = objwaste;
                if (s->objects > max_objects)
                        max_objects = s->objects;
                if (used > max_used)
                        max_used = used;
                if (s->objects_partial > max_partobj)
                        max_partobj = s->objects_partial;
                if (percentage_partial_slabs > max_ppart)
                        max_ppart = percentage_partial_slabs;
                if (percentage_partial_objs > max_ppartobj)
                        max_ppartobj = percentage_partial_objs;
                if (s->slab_size > max_memobj)
                        max_memobj = s->slab_size;

                total_partial += s->partial;
                total_slabs += s->slabs;
                total_size += size;
                total_waste += wasted;

                total_objects += s->objects;
                total_used += used;
                total_partobj += s->objects_partial;
                total_ppart += percentage_partial_slabs;
                total_ppartobj += percentage_partial_objs;

                total_objwaste += s->objects * objwaste;
                total_objsize += s->objects * s->slab_size;
        }

        if (!total_objects) {
                printf("No objects\n");
                return;
        }
        if (!used_slabs) {
                printf("No slabs\n");
                return;
        }

        /* Per slab averages */
        avg_partial = total_partial / used_slabs;
        avg_slabs = total_slabs / used_slabs;
        avg_size = total_size / used_slabs;
        avg_waste = total_waste / used_slabs;

        avg_objects = total_objects / used_slabs;
        avg_used = total_used / used_slabs;
        avg_partobj = total_partobj / used_slabs;
        avg_ppart = total_ppart / used_slabs;
        avg_ppartobj = total_ppartobj / used_slabs;

        /* Per object object sizes */
        avg_objsize = total_used / total_objects;
        avg_objwaste = total_objwaste / total_objects;
        avg_partobj = total_partobj * 100 / total_objects;
        avg_memobj = total_objsize / total_objects;

        printf("Slabcache Totals\n");
        printf("----------------\n");
        printf("Slabcaches : %15d   Aliases  : %11d->%-3d  Active:    %3d\n",
                        slabs, aliases, alias_targets, used_slabs);

        store_size(b1, total_size);store_size(b2, total_waste);
        store_size(b3, total_waste * 100 / total_used);
        printf("Memory used: %15s   # Loss   : %15s   MRatio:%6s%%\n", b1, b2, b3);

        store_size(b1, total_objects);store_size(b2, total_partobj);
        store_size(b3, total_partobj * 100 / total_objects);
        printf("# Objects  : %15s   # PartObj: %15s   ORatio:%6s%%\n", b1, b2, b3);

        printf("\n");
        printf("Per Cache         Average              "
                "Min              Max            Total\n");
        printf("---------------------------------------"
                "-------------------------------------\n");

        store_size(b1, avg_objects);store_size(b2, min_objects);
        store_size(b3, max_objects);store_size(b4, total_objects);
        printf("#Objects  %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_slabs);store_size(b2, min_slabs);
        store_size(b3, max_slabs);store_size(b4, total_slabs);
        printf("#Slabs    %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_partial);store_size(b2, min_partial);
        store_size(b3, max_partial);store_size(b4, total_partial);
        printf("#PartSlab %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);
        store_size(b1, avg_ppart);store_size(b2, min_ppart);
        store_size(b3, max_ppart);
        store_size(b4, total_partial * 100  / total_slabs);
        printf("%%PartSlab%15s%% %15s%% %15s%% %15s%%\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_partobj);store_size(b2, min_partobj);
        store_size(b3, max_partobj);
        store_size(b4, total_partobj);
        printf("PartObjs  %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_ppartobj);store_size(b2, min_ppartobj);
        store_size(b3, max_ppartobj);
        store_size(b4, total_partobj * 100 / total_objects);
        printf("%% PartObj%15s%% %15s%% %15s%% %15s%%\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_size);store_size(b2, min_size);
        store_size(b3, max_size);store_size(b4, total_size);
        printf("Memory    %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_used);store_size(b2, min_used);
        store_size(b3, max_used);store_size(b4, total_used);
        printf("Used      %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);

        store_size(b1, avg_waste);store_size(b2, min_waste);
        store_size(b3, max_waste);store_size(b4, total_waste);
        printf("Loss      %15s  %15s  %15s  %15s\n",
                        b1,     b2,     b3,     b4);

        printf("\n");
        printf("Per Object        Average              "
                "Min              Max\n");
        printf("---------------------------------------"
                "--------------------\n");

        store_size(b1, avg_memobj);store_size(b2, min_memobj);
        store_size(b3, max_memobj);
        printf("Memory    %15s  %15s  %15s\n",
                        b1,     b2,     b3);
        store_size(b1, avg_objsize);store_size(b2, min_objsize);
        store_size(b3, max_objsize);
        printf("User      %15s  %15s  %15s\n",
                        b1,     b2,     b3);

        store_size(b1, avg_objwaste);store_size(b2, min_objwaste);
        store_size(b3, max_objwaste);
        printf("Loss      %15s  %15s  %15s\n",
                        b1,     b2,     b3);
}

static void sort_slabs(void)
{
        struct slabinfo *s1,*s2;

        for (s1 = slabinfo; s1 < slabinfo + slabs; s1++) {
                for (s2 = s1 + 1; s2 < slabinfo + slabs; s2++) {
                        int result;

                        if (sort_size) {
                                if (slab_size(s1) == slab_size(s2))
                                        result = strcasecmp(s1->name, s2->name);
                                else
                                        result = slab_size(s1) < slab_size(s2);
                        } else if (sort_active) {
                                if (slab_activity(s1) == slab_activity(s2))
                                        result = strcasecmp(s1->name, s2->name);
                                else
                                        result = slab_activity(s1) < slab_activity(s2);
                        } else if (sort_loss) {
                                if (slab_waste(s1) == slab_waste(s2))
                                        result = strcasecmp(s1->name, s2->name);
                                else
                                        result = slab_waste(s1) < slab_waste(s2);
                        } else if (sort_partial) {
                                if (s1->partial == s2->partial)
                                        result = strcasecmp(s1->name, s2->name);
                                else
                                        result = s1->partial < s2->partial;
                        } else
                                result = strcasecmp(s1->name, s2->name);

                        if (show_inverted)
                                result = -result;

                        if (result > 0) {
                                struct slabinfo t;

                                memcpy(&t, s1, sizeof(struct slabinfo));
                                memcpy(s1, s2, sizeof(struct slabinfo));
                                memcpy(s2, &t, sizeof(struct slabinfo));
                        }
                }
        }
}

static void sort_aliases(void)
{
        struct aliasinfo *a1,*a2;

        for (a1 = aliasinfo; a1 < aliasinfo + aliases; a1++) {
                for (a2 = a1 + 1; a2 < aliasinfo + aliases; a2++) {
                        char *n1, *n2;

                        n1 = a1->name;
                        n2 = a2->name;
                        if (show_alias && !show_inverted) {
                                n1 = a1->ref;
                                n2 = a2->ref;
                        }
                        if (strcasecmp(n1, n2) > 0) {
                                struct aliasinfo t;

                                memcpy(&t, a1, sizeof(struct aliasinfo));
                                memcpy(a1, a2, sizeof(struct aliasinfo));
                                memcpy(a2, &t, sizeof(struct aliasinfo));
                        }
                }
        }
}

static void link_slabs(void)
{
        struct aliasinfo *a;
        struct slabinfo *s;

        for (a = aliasinfo; a < aliasinfo + aliases; a++) {

                for (s = slabinfo; s < slabinfo + slabs; s++)
                        if (strcmp(a->ref, s->name) == 0) {
                                a->slab = s;
                                s->refs++;
                                break;
                        }
                if (s == slabinfo + slabs)
                        fatal("Unresolved alias %s\n", a->ref);
        }
}

static void alias(void)
{
        struct aliasinfo *a;
        char *active = NULL;

        sort_aliases();
        link_slabs();

        for(a = aliasinfo; a < aliasinfo + aliases; a++) {

                if (!show_single_ref && a->slab->refs == 1)
                        continue;

                if (!show_inverted) {
                        if (active) {
                                if (strcmp(a->slab->name, active) == 0) {
                                        printf(" %s", a->name);
                                        continue;
                                }
                        }
                        printf("\n%-12s <- %s", a->slab->name, a->name);
                        active = a->slab->name;
                }
                else
                        printf("%-15s -> %s\n", a->name, a->slab->name);
        }
        if (active)
                printf("\n");
}


static void rename_slabs(void)
{
        struct slabinfo *s;
        struct aliasinfo *a;

        for (s = slabinfo; s < slabinfo + slabs; s++) {
                if (*s->name != ':')
                        continue;

                if (s->refs > 1 && !show_first_alias)
                        continue;

                a = find_one_alias(s);

                if (a)
                        s->name = a->name;
                else {
                        s->name = "*";
                        actual_slabs--;
                }
        }
}

static int slab_mismatch(char *slab)
{
        return regexec(&pattern, slab, 0, NULL, 0);
}

static void read_slab_dir(void)
{
        DIR *dir;
        struct dirent *de;
        struct slabinfo *slab = slabinfo;
        struct aliasinfo *alias = aliasinfo;
        char *p;
        char *t;
        int count;

        if (chdir("/sys/kernel/slab") && chdir("/sys/slab"))
                fatal("SYSFS support for SLUB not active\n");

        dir = opendir(".");
        while ((de = readdir(dir))) {
                if (de->d_name[0] == '.' ||
                        (de->d_name[0] != ':' && slab_mismatch(de->d_name)))
                                continue;
                switch (de->d_type) {
                   case DT_LNK:
                        if (alias - aliasinfo == MAX_ALIASES)
                                fatal("Too many aliases\n");
                        alias->name = strdup(de->d_name);
                        count = readlink(de->d_name, buffer, sizeof(buffer)-1);

                        if (count < 0)
                                fatal("Cannot read symlink %s\n", de->d_name);

                        buffer[count] = 0;
                        p = buffer + count;
                        while (p > buffer && p[-1] != '/')
                                p--;
                        alias->ref = strdup(p);
                        alias++;
                        break;
                   case DT_DIR:
                        if (slab - slabinfo == MAX_SLABS)
                                fatal("Too many slabs\n");
                        if (chdir(de->d_name))
                                fatal("Unable to access slab %s\n", slab->name);
                        slab->name = strdup(de->d_name);
                        slab->alias = 0;
                        slab->refs = 0;
                        slab->aliases = get_obj("aliases");
                        slab->align = get_obj("align");
                        slab->cache_dma = get_obj("cache_dma");
                        slab->cpu_slabs = get_obj("cpu_slabs");
                        slab->destroy_by_rcu = get_obj("destroy_by_rcu");
                        slab->hwcache_align = get_obj("hwcache_align");
                        slab->object_size = get_obj("object_size");
                        slab->objects = get_obj("objects");
                        slab->objects_partial = get_obj("objects_partial");
                        slab->objects_total = get_obj("objects_total");
                        slab->objs_per_slab = get_obj("objs_per_slab");
                        slab->order = get_obj("order");
                        slab->partial = get_obj("partial");
                        slab->partial = get_obj_and_str("partial", &t);
                        decode_numa_list(slab->numa_partial, t);
                        free(t);
                        slab->poison = get_obj("poison");
                        slab->reclaim_account = get_obj("reclaim_account");
                        slab->red_zone = get_obj("red_zone");
                        slab->sanity_checks = get_obj("sanity_checks");
                        slab->slab_size = get_obj("slab_size");
                        slab->slabs = get_obj_and_str("slabs", &t);
                        decode_numa_list(slab->numa, t);
                        free(t);
                        slab->store_user = get_obj("store_user");
                        slab->trace = get_obj("trace");
                        slab->alloc_fastpath = get_obj("alloc_fastpath");
                        slab->alloc_slowpath = get_obj("alloc_slowpath");
                        slab->free_fastpath = get_obj("free_fastpath");
                        slab->free_slowpath = get_obj("free_slowpath");
                        slab->free_frozen= get_obj("free_frozen");
                        slab->free_add_partial = get_obj("free_add_partial");
                        slab->free_remove_partial = get_obj("free_remove_partial");
                        slab->alloc_from_partial = get_obj("alloc_from_partial");
                        slab->alloc_slab = get_obj("alloc_slab");
                        slab->alloc_refill = get_obj("alloc_refill");
                        slab->free_slab = get_obj("free_slab");
                        slab->cpuslab_flush = get_obj("cpuslab_flush");
                        slab->deactivate_full = get_obj("deactivate_full");
                        slab->deactivate_empty = get_obj("deactivate_empty");
                        slab->deactivate_to_head = get_obj("deactivate_to_head");
                        slab->deactivate_to_tail = get_obj("deactivate_to_tail");
                        slab->deactivate_remote_frees = get_obj("deactivate_remote_frees");
                        slab->order_fallback = get_obj("order_fallback");
                        slab->cmpxchg_double_cpu_fail = get_obj("cmpxchg_double_cpu_fail");
                        slab->cmpxchg_double_fail = get_obj("cmpxchg_double_fail");
                        slab->cpu_partial_alloc = get_obj("cpu_partial_alloc");
                        slab->cpu_partial_free = get_obj("cpu_partial_free");
                        slab->alloc_node_mismatch = get_obj("alloc_node_mismatch");
                        slab->deactivate_bypass = get_obj("deactivate_bypass");
                        if (chdir(".."))
                                fatal("Unable to chdir from slab ../%s\n",
                                      slab->name);
                        if (slab->name[0] == ':')
                                alias_targets++;
                        slab++;
                        break;
                   default :
                        fatal("Unknown file type %lx\n", de->d_type);
                }
        }
        closedir(dir);
        slabs = slab - slabinfo;
        actual_slabs = slabs;
        aliases = alias - aliasinfo;
}

static void output_slabs(void)
{
        struct slabinfo *slab;
        int lines = output_lines;

        for (slab = slabinfo; (slab < slabinfo + slabs) &&
                        lines != 0; slab++) {

                if (slab->alias)
                        continue;

                if (lines != -1)
                        lines--;

                if (show_numa)
                        slab_numa(slab, 0);
                else if (show_track)
                        show_tracking(slab);
                else if (validate)
                        slab_validate(slab);
                else if (shrink)
                        slab_shrink(slab);
                else if (set_debug)
                        slab_debug(slab);
                else if (show_ops)
                        ops(slab);
                else if (show_slab)
                        slabcache(slab);
                else if (show_report)
                        report(slab);
        }
}

static void _xtotals(char *heading, char *underline,
                     int loss, int size, int partial)
{
        printf("%s%s", heading, underline);
        line = 0;
        sort_loss = loss;
        sort_size = size;
        sort_partial = partial;
        sort_slabs();
        output_slabs();
}

static void xtotals(void)
{
        char *heading, *underline;

        totals();

        link_slabs();
        rename_slabs();

        heading = "\nSlabs sorted by size\n";
        underline = "--------------------\n";
        _xtotals(heading, underline, 0, 1, 0);

        heading = "\nSlabs sorted by loss\n";
        underline = "--------------------\n";
        _xtotals(heading, underline, 1, 0, 0);

        heading = "\nSlabs sorted by number of partial slabs\n";
        underline = "---------------------------------------\n";
        _xtotals(heading, underline, 0, 0, 1);

        printf("\n");
}

struct option opts[] = {
        { "aliases", no_argument, NULL, 'a' },
        { "activity", no_argument, NULL, 'A' },
        { "Bytes", no_argument, NULL, 'B'},
        { "debug", optional_argument, NULL, 'd' },
        { "display-activity", no_argument, NULL, 'D' },
        { "empty", no_argument, NULL, 'e' },
        { "first-alias", no_argument, NULL, 'f' },
        { "help", no_argument, NULL, 'h' },
        { "inverted", no_argument, NULL, 'i'},
        { "slabs", no_argument, NULL, 'l' },
        { "Loss", no_argument, NULL, 'L'},
        { "numa", no_argument, NULL, 'n' },
        { "lines", required_argument, NULL, 'N'},
        { "ops", no_argument, NULL, 'o' },
        { "partial", no_argument, NULL, 'P'},
        { "report", no_argument, NULL, 'r' },
        { "shrink", no_argument, NULL, 's' },
        { "Size", no_argument, NULL, 'S'},
        { "tracking", no_argument, NULL, 't'},
        { "Totals", no_argument, NULL, 'T'},
        { "Unreclaim", no_argument, NULL, 'U'},
        { "validate", no_argument, NULL, 'v' },
        { "Xtotals", no_argument, NULL, 'X'},
        { "zero", no_argument, NULL, 'z' },
        { "1ref", no_argument, NULL, '1'},
        { NULL, 0, NULL, 0 }
};

int main(int argc, char *argv[])
{
        int c;
        int err;
        char *pattern_source;

        page_size = getpagesize();

        while ((c = getopt_long(argc, argv, "aABd::DefhilLnN:oPrsStTUvXz1",
                                                opts, NULL)) != -1)
                switch (c) {
                case 'a':
                        show_alias = 1;
                        break;
                case 'A':
                        sort_active = 1;
                        break;
                case 'B':
                        show_bytes = 1;
                        break;
                case 'd':
                        set_debug = 1;
                        if (!debug_opt_scan(optarg))
                                fatal("Invalid debug option '%s'\n", optarg);
                        break;
                case 'D':
                        show_activity = 1;
                        break;
                case 'e':
                        show_empty = 1;
                        break;
                case 'f':
                        show_first_alias = 1;
                        break;
                case 'h':
                        usage();
                        return 0;
                case 'i':
                        show_inverted = 1;
                        break;
                case 'l':
                        show_slab = 1;
                        break;
                case 'L':
                        sort_loss = 1;
                        break;
                case 'n':
                        show_numa = 1;
                        break;
                case 'N':
                        if (optarg) {
                                output_lines = atoi(optarg);
                                if (output_lines < 1)
                                        output_lines = 1;
                        }
                        break;
                case 'o':
                        show_ops = 1;
                        break;
                case 'r':
                        show_report = 1;
                        break;
                case 'P':
                        sort_partial = 1;
                        break;
                case 's':
                        shrink = 1;
                        break;
                case 'S':
                        sort_size = 1;
                        break;
                case 't':
                        show_track = 1;
                        break;
                case 'T':
                        show_totals = 1;
                        break;
                case 'U':
                        unreclaim_only = 1;
                        break;
                case 'v':
                        validate = 1;
                        break;
                case 'X':
                        if (output_lines == -1)
                                output_lines = 1;
                        extended_totals = 1;
                        show_bytes = 1;
                        break;
                case 'z':
                        skip_zero = 0;
                        break;
                case '1':
                        show_single_ref = 1;
                        break;
                default:
                        fatal("%s: Invalid option '%c'\n", argv[0], optopt);

        }

        if (!show_slab && !show_alias && !show_track && !show_report
                && !validate && !shrink && !set_debug && !show_ops)
                        show_slab = 1;

        if (argc > optind)
                pattern_source = argv[optind];
        else
                pattern_source = ".*";

        err = regcomp(&pattern, pattern_source, REG_ICASE|REG_NOSUB);
        if (err)
                fatal("%s: Invalid pattern '%s' code %d\n",
                        argv[0], pattern_source, err);
        read_slab_dir();
        if (show_alias) {
                alias();
        } else if (extended_totals) {
                xtotals();
        } else if (show_totals) {
                totals();
        } else {
                link_slabs();
                rename_slabs();
                sort_slabs();
                output_slabs();
        }
        return 0;
}