slabinfo.c

linux 内核源代码

/*
 * Slabinfo: Tool to get reports about slabs
 *
 * (C) 2007 sgi, Christoph Lameter <[e-mail]>
 *
 * Compile by:
 *
 * 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;
	int hwcache_align, object_size, objs_per_slab;
	int sanity_checks, slab_size, store_user, trace;
	int order, poison, reclaim_account, red_zone;
	unsigned long partial, objects, slabs;
	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 = 0;
int actual_slabs = 0;
int aliases = 0;
int alias_targets = 0;
int highest_node = 0;

char buffer[4096];

int show_empty = 0;
int show_report = 0;
int show_alias = 0;
int show_slab = 0;
int skip_zero = 1;
int show_numa = 0;
int show_track = 0;
int show_first_alias = 0;
int validate = 0;
int shrink = 0;
int show_inverted = 0;
int show_single_ref = 0;
int show_totals = 0;
int sort_size = 0;
int set_debug = 0;
int show_ops = 0;

/* Debug options */
int sanity = 0;
int redzone = 0;
int poison = 0;
int tracking = 0;
int tracing = 0;

int page_size;

regex_t pattern;

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

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

void usage(void)
{
	printf("slabinfo 5/7/2007. (c) 2007 sgi. [e-mail]\n\n"
		"slabinfo [-ahnpvtsz] [-d debugopts] [slab-regexp]\n"
		"-a|--aliases           Show aliases\n"
		"-d<options>|--debug=<options> Set/Clear Debug options\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"
		"-n|--numa              Show NUMA information\n"
		"-o|--ops		Show kmem_cache_ops\n"
		"-s|--shrink            Shrink slabs\n"
		"-r|--report		Detailed report on single slabs\n"
		"-S|--Size              Sort by size\n"
		"-t|--tracking          Show alloc/free information\n"
		"-T|--Totals            Show summary information\n"
		"-v|--validate          Validate slabs\n"
		"-z|--zero              Include empty slabs\n"
		"-1|--1ref              Single reference\n"
		"\nValid debug options (FZPUT may be combined)\n"
		"a / A          Switch on all debug options (=FZUP)\n"
		"-              Switch off all debug options\n"
		"f / F          Sanity Checks (SLAB_DEBUG_FREE)\n"
		"z / Z          Redzoning\n"
		"p / P          Poisoning\n"
		"u / U          Tracking\n"
		"t / T          Tracing\n"
	);
}

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

	if (!f)
		buffer[0] = 0;
	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
 */
unsigned long get_obj(const char *name)
{
	if (!read_obj(name))
		return 0;

	return atol(buffer);
}

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;
}

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);
}

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;
}


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

	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;
}

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++;
	}
}

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

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

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

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

int line = 0;

void first_line(void)
{
	printf("Name                   Objects Objsize    Space "
		"Slabs/Part/Cpu  O/S O %%Fr %%Ef Flg\n");
}

/*
 * Find the shortest alias of a slab
 */
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;
}

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

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++;
}

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

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

}

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

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

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

	printf("\nSlabcache: %-20s  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);
}

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

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

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

	store_size(size_str, slab_size(s));
	snprintf(dist_str, 40, "%lu/%lu/%d", s->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;
	printf("%-21s %8ld %7d %8s %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.
 */
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;
}

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;
}

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

	if (sanity && !s->sanity_checks) {
		set_obj(s, "sanity", 1);
	}
	if (!sanity && s->sanity_checks) {
		if (slab_empty(s))
			set_obj(s, "sanity", 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);
}

void totals(void)
{
	struct slabinfo *s;