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 500
#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)
{
	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);
		if (buffer[strlen(buffer)] == '\n')
			buffer[strlen(buffer)] = 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:
			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 (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");
			chdir("..");
			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;
	if (slabs > MAX_SLABS)
		fatal("Too many slabs\n");
	if (aliases > MAX_ALIASES)
		fatal("Too many aliases\n");
}

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;
}