linux/lib/debugobjects.c at master · rata/linux · GitHub

History

1096 lines (929 loc) · 26.2 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

402

403

404

405

406

407

408

409

410

411

412

413

414

415

416

417

418

419

420

421

422

423

424

425

426

427

428

429

430

431

432

433

434

435

436

437

438

439

440

441

442

443

444

445

446

447

448

449

450

451

452

453

454

455

456

457

458

459

460

461

462

463

464

465

466

467

468

469

470

471

472

473

474

475

476

477

478

479

480

481

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

499

500

501

502

503

504

505

506

507

508

509

510

511

512

513

514

515

516

517

518

519

520

521

522

523

524

525

526

527

528

529

530

531

532

533

534

535

536

537

538

539

540

541

542

543

544

545

546

547

548

549

550

551

552

553

554

555

556

557

558

559

560

561

562

563

564

565

566

567

568

569

570

571

572

573

574

575

576

577

578

579

580

581

582

583

584

585

586

587

588

589

590

591

592

593

594

595

596

597

598

599

600

601

602

603

604

605

606

607

608

609

610

611

612

613

614

615

616

617

618

619

620

621

622

623

624

625

626

627

628

629

630

631

632

633

634

635

636

637

638

639

640

641

642

643

644

645

646

647

648

649

650

651

652

653

654

655

656

657

658

659

660

661

662

663

664

665

666

667

668

669

670

671

672

673

674

675

676

677

678

679

680

681

682

683

684

685

686

687

688

689

690

691

692

693

694

695

696

697

698

699

700

701

702

703

704

705

706

707

708

709

710

711

712

713

714

715

716

717

718

719

720

721

722

723

724

725

726

727

728

729

730

731

732

733

734

735

736

737

738

739

740

741

742

743

744

745

746

747

748

749

750

751

752

753

754

755

756

757

758

759

760

761

762

763

764

765

766

767

768

769

770

771

772

773

774

775

776

777

778

779

780

781

782

783

784

785

786

787

788

789

790

791

792

793

794

795

796

797

798

799

800

801

802

803

804

805

806

807

808

809

810

811

812

813

814

815

816

817

818

819

820

821

822

823

824

825

826

827

828

829

830

831

832

833

834

835

836

837

838

839

840

841

842

843

844

845

846

847

848

849

850

851

852

853

854

855

856

857

858

859

860

861

862

863

864

865

866

867

868

869

870

871

872

873

874

875

876

877

878

879

880

881

882

883

884

885

886

887

888

889

890

891

892

893

894

895

896

897

898

899

900

901

902

903

904

905

906

907

908

909

910

911

912

913

914

915

916

917

918

919

920

921

922

923

924

925

926

927

928

929

930

931

932

933

934

935

936

937

938

939

940

941

942

943

944

945

946

947

948

949

950

951

952

953

954

955

956

957

958

959

960

961

962

963

964

965

966

967

968

969

970

971

972

973

974

975

976

977

978

979

980

981

982

983

984

985

986

987

988

989

990

991

992

993

994

995

996

997

998

999

1000

* Generic infrastructure for lifetime debugging of objects.

* Started by Thomas Gleixner

* For licencing details see kernel-base/COPYING

#include <linux/debugobjects.h>

#include <linux/interrupt.h>

#include <linux/sched.h>

#include <linux/seq_file.h>

#include <linux/debugfs.h>

#include <linux/slab.h>

#include <linux/hash.h>

#define ODEBUG_HASH_BITS 14

#define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS)

#define ODEBUG_POOL_SIZE 512

#define ODEBUG_POOL_MIN_LEVEL 256

#define ODEBUG_CHUNK_SHIFT PAGE_SHIFT

#define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT)

#define ODEBUG_CHUNK_MASK (~(ODEBUG_CHUNK_SIZE - 1))

struct debug_bucket {

struct hlist_head list;

raw_spinlock_t lock;

};

static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE];

static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata;

static DEFINE_RAW_SPINLOCK(pool_lock);

static HLIST_HEAD(obj_pool);

static int obj_pool_min_free = ODEBUG_POOL_SIZE;

static int obj_pool_free = ODEBUG_POOL_SIZE;

static int obj_pool_used;

static int obj_pool_max_used;

static struct kmem_cache *obj_cache;

static int debug_objects_maxchain __read_mostly;

static int debug_objects_fixups __read_mostly;

static int debug_objects_warnings __read_mostly;

static int debug_objects_enabled __read_mostly

= CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT;

static struct debug_obj_descr *descr_test __read_mostly;

static void free_obj_work(struct work_struct *work);

static DECLARE_WORK(debug_obj_work, free_obj_work);

static int __init enable_object_debug(char *str)

{

debug_objects_enabled = 1;

return 0;

}

static int __init disable_object_debug(char *str)

{

debug_objects_enabled = 0;

return 0;

}

early_param("debug_objects", enable_object_debug);

early_param("no_debug_objects", disable_object_debug);

static const char *obj_states[ODEBUG_STATE_MAX] = {

[ODEBUG_STATE_NONE] = "none",

[ODEBUG_STATE_INIT] = "initialized",

[ODEBUG_STATE_INACTIVE] = "inactive",

[ODEBUG_STATE_ACTIVE] = "active",

[ODEBUG_STATE_DESTROYED] = "destroyed",

[ODEBUG_STATE_NOTAVAILABLE] = "not available",

};

static void fill_pool(void)

{

gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;

struct debug_obj *new;

unsigned long flags;

if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL))

return;

if (unlikely(!obj_cache))

return;

while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) {

new = kmem_cache_zalloc(obj_cache, gfp);

if (!new)

return;

raw_spin_lock_irqsave(&pool_lock, flags);

hlist_add_head(&new->node, &obj_pool);

obj_pool_free++;

raw_spin_unlock_irqrestore(&pool_lock, flags);

}

* Lookup an object in the hash bucket.

static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b)

{

struct debug_obj *obj;

int cnt = 0;

hlist_for_each_entry(obj, &b->list, node) {

cnt++;

if (obj->object == addr)

return obj;

}

if (cnt > debug_objects_maxchain)

debug_objects_maxchain = cnt;

return NULL;

}

* Allocate a new object. If the pool is empty, switch off the debugger.

* Must be called with interrupts disabled.

static struct debug_obj *

alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)

{

struct debug_obj *obj = NULL;

raw_spin_lock(&pool_lock);

if (obj_pool.first) {

obj = hlist_entry(obj_pool.first, typeof(*obj), node);

obj->object = addr;

obj->descr = descr;

obj->state = ODEBUG_STATE_NONE;

obj->astate = 0;

hlist_del(&obj->node);

hlist_add_head(&obj->node, &b->list);

obj_pool_used++;

if (obj_pool_used > obj_pool_max_used)

obj_pool_max_used = obj_pool_used;

obj_pool_free--;

if (obj_pool_free < obj_pool_min_free)

obj_pool_min_free = obj_pool_free;

}

raw_spin_unlock(&pool_lock);

return obj;

}

* workqueue function to free objects.

static void free_obj_work(struct work_struct *work)

{

struct debug_obj *obj;

unsigned long flags;

raw_spin_lock_irqsave(&pool_lock, flags);

while (obj_pool_free > ODEBUG_POOL_SIZE) {

obj = hlist_entry(obj_pool.first, typeof(*obj), node);

hlist_del(&obj->node);

obj_pool_free--;

* We release pool_lock across kmem_cache_free() to

* avoid contention on pool_lock.

raw_spin_unlock_irqrestore(&pool_lock, flags);

kmem_cache_free(obj_cache, obj);

raw_spin_lock_irqsave(&pool_lock, flags);

}

raw_spin_unlock_irqrestore(&pool_lock, flags);

}

* Put the object back into the pool and schedule work to free objects

* if necessary.

static void free_object(struct debug_obj *obj)

{

unsigned long flags;

int sched = 0;

raw_spin_lock_irqsave(&pool_lock, flags);

* schedule work when the pool is filled and the cache is

* initialized:

if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache)

sched = keventd_up();

hlist_add_head(&obj->node, &obj_pool);

obj_pool_free++;

obj_pool_used--;

raw_spin_unlock_irqrestore(&pool_lock, flags);

if (sched)

schedule_work(&debug_obj_work);

}

* We run out of memory. That means we probably have tons of objects

* allocated.

static void debug_objects_oom(void)

{

struct debug_bucket *db = obj_hash;

struct hlist_node *tmp;

HLIST_HEAD(freelist);

struct debug_obj *obj;

unsigned long flags;

int i;

printk(KERN_WARNING "ODEBUG: Out of memory. ODEBUG disabled\n");

for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {

raw_spin_lock_irqsave(&db->lock, flags);

hlist_move_list(&db->list, &freelist);

raw_spin_unlock_irqrestore(&db->lock, flags);

/* Now free them */

hlist_for_each_entry_safe(obj, tmp, &freelist, node) {

hlist_del(&obj->node);

free_object(obj);

}

* We use the pfn of the address for the hash. That way we can check

* for freed objects simply by checking the affected bucket.

static struct debug_bucket *get_bucket(unsigned long addr)

{

unsigned long hash;

hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS);

return &obj_hash[hash];

}

static void debug_print_object(struct debug_obj *obj, char *msg)

{

struct debug_obj_descr *descr = obj->descr;

static int limit;

if (limit < 5 && descr != descr_test) {

void *hint = descr->debug_hint ?

descr->debug_hint(obj->object) : NULL;

limit++;

WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) "

"object type: %s hint: %pS\n",

msg, obj_states[obj->state], obj->astate,

descr->name, hint);

}

debug_objects_warnings++;

}

* Try to repair the damage, so we have a better chance to get useful

* debug output.

static int

debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),

void * addr, enum debug_obj_state state)

{

int fixed = 0;

if (fixup)

fixed = fixup(addr, state);

debug_objects_fixups += fixed;

return fixed;

}

static void debug_object_is_on_stack(void *addr, int onstack)

{

int is_on_stack;

static int limit;

if (limit > 4)

return;

is_on_stack = object_is_on_stack(addr);

if (is_on_stack == onstack)

return;

limit++;

if (is_on_stack)

printk(KERN_WARNING

"ODEBUG: object is on stack, but not annotated\n");

else

printk(KERN_WARNING

"ODEBUG: object is not on stack, but annotated\n");

WARN_ON(1);

}

static void

__debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)

{

enum debug_obj_state state;

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

fill_pool();

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (!obj) {

obj = alloc_object(addr, db, descr);

if (!obj) {

debug_objects_enabled = 0;

raw_spin_unlock_irqrestore(&db->lock, flags);

debug_objects_oom();

return;

}

debug_object_is_on_stack(addr, onstack);

}

switch (obj->state) {

case ODEBUG_STATE_NONE:

case ODEBUG_STATE_INIT:

case ODEBUG_STATE_INACTIVE:

obj->state = ODEBUG_STATE_INIT;

break;

case ODEBUG_STATE_ACTIVE:

debug_print_object(obj, "init");

state = obj->state;

raw_spin_unlock_irqrestore(&db->lock, flags);

debug_object_fixup(descr->fixup_init, addr, state);

return;

case ODEBUG_STATE_DESTROYED:

debug_print_object(obj, "init");

break;

default:

break;

}

raw_spin_unlock_irqrestore(&db->lock, flags);

}

/**

* debug_object_init - debug checks when an object is initialized

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

void debug_object_init(void *addr, struct debug_obj_descr *descr)

{

if (!debug_objects_enabled)

return;

__debug_object_init(addr, descr, 0);

}

/**

* debug_object_init_on_stack - debug checks when an object on stack is

* initialized

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)

{

if (!debug_objects_enabled)

return;

__debug_object_init(addr, descr, 1);

}

/**

* debug_object_activate - debug checks when an object is activated

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

* Returns 0 for success, -EINVAL for check failed.

int debug_object_activate(void *addr, struct debug_obj_descr *descr)

{

enum debug_obj_state state;

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

int ret;

struct debug_obj o = { .object = addr,

.state = ODEBUG_STATE_NOTAVAILABLE,

.descr = descr };

if (!debug_objects_enabled)

return 0;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (obj) {

switch (obj->state) {

case ODEBUG_STATE_INIT:

case ODEBUG_STATE_INACTIVE:

obj->state = ODEBUG_STATE_ACTIVE;

ret = 0;

break;

case ODEBUG_STATE_ACTIVE:

debug_print_object(obj, "activate");

state = obj->state;

raw_spin_unlock_irqrestore(&db->lock, flags);

ret = debug_object_fixup(descr->fixup_activate, addr, state);

return ret ? -EINVAL : 0;

case ODEBUG_STATE_DESTROYED:

debug_print_object(obj, "activate");

ret = -EINVAL;

break;

default:

ret = 0;

break;

}

raw_spin_unlock_irqrestore(&db->lock, flags);

return ret;

}

raw_spin_unlock_irqrestore(&db->lock, flags);

* This happens when a static object is activated. We

* let the type specific code decide whether this is

* true or not.

if (debug_object_fixup(descr->fixup_activate, addr,

ODEBUG_STATE_NOTAVAILABLE)) {

debug_print_object(&o, "activate");

return -EINVAL;

}

return 0;

}

/**

* debug_object_deactivate - debug checks when an object is deactivated

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)

{

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

if (!debug_objects_enabled)

return;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (obj) {

switch (obj->state) {

case ODEBUG_STATE_INIT:

case ODEBUG_STATE_INACTIVE:

case ODEBUG_STATE_ACTIVE:

if (!obj->astate)

obj->state = ODEBUG_STATE_INACTIVE;

else

debug_print_object(obj, "deactivate");

break;

case ODEBUG_STATE_DESTROYED:

debug_print_object(obj, "deactivate");

break;

default:

break;

}

} else {

struct debug_obj o = { .object = addr,

.state = ODEBUG_STATE_NOTAVAILABLE,

.descr = descr };

debug_print_object(&o, "deactivate");

}

raw_spin_unlock_irqrestore(&db->lock, flags);

}

/**

* debug_object_destroy - debug checks when an object is destroyed

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

void debug_object_destroy(void *addr, struct debug_obj_descr *descr)

{

enum debug_obj_state state;

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

if (!debug_objects_enabled)

return;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (!obj)

goto out_unlock;

switch (obj->state) {

case ODEBUG_STATE_NONE:

case ODEBUG_STATE_INIT:

case ODEBUG_STATE_INACTIVE:

obj->state = ODEBUG_STATE_DESTROYED;

break;

case ODEBUG_STATE_ACTIVE:

debug_print_object(obj, "destroy");

state = obj->state;

raw_spin_unlock_irqrestore(&db->lock, flags);

debug_object_fixup(descr->fixup_destroy, addr, state);

return;

case ODEBUG_STATE_DESTROYED:

debug_print_object(obj, "destroy");

break;

default:

break;

}

out_unlock:

raw_spin_unlock_irqrestore(&db->lock, flags);

}

/**

* debug_object_free - debug checks when an object is freed

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

void debug_object_free(void *addr, struct debug_obj_descr *descr)

{

enum debug_obj_state state;

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

if (!debug_objects_enabled)

return;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (!obj)

goto out_unlock;

switch (obj->state) {

case ODEBUG_STATE_ACTIVE:

debug_print_object(obj, "free");

state = obj->state;

raw_spin_unlock_irqrestore(&db->lock, flags);

debug_object_fixup(descr->fixup_free, addr, state);

return;

default:

hlist_del(&obj->node);

raw_spin_unlock_irqrestore(&db->lock, flags);

free_object(obj);

return;

}

out_unlock:

raw_spin_unlock_irqrestore(&db->lock, flags);

}

/**

* debug_object_assert_init - debug checks when object should be init-ed

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

void debug_object_assert_init(void *addr, struct debug_obj_descr *descr)

{

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

if (!debug_objects_enabled)

return;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (!obj) {

struct debug_obj o = { .object = addr,

.state = ODEBUG_STATE_NOTAVAILABLE,

.descr = descr };

raw_spin_unlock_irqrestore(&db->lock, flags);

* Maybe the object is static. Let the type specific

* code decide what to do.

if (debug_object_fixup(descr->fixup_assert_init, addr,

ODEBUG_STATE_NOTAVAILABLE))

debug_print_object(&o, "assert_init");

return;

}

raw_spin_unlock_irqrestore(&db->lock, flags);

}

/**

* debug_object_active_state - debug checks object usage state machine

* @addr: address of the object

* @descr: pointer to an object specific debug description structure

* @expect: expected state

* @next: state to move to if expected state is found

void

debug_object_active_state(void *addr, struct debug_obj_descr *descr,

unsigned int expect, unsigned int next)

{

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

if (!debug_objects_enabled)

return;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (obj) {

switch (obj->state) {

case ODEBUG_STATE_ACTIVE:

if (obj->astate == expect)

obj->astate = next;

else

debug_print_object(obj, "active_state");

break;

default:

debug_print_object(obj, "active_state");

break;

}

} else {

struct debug_obj o = { .object = addr,

.state = ODEBUG_STATE_NOTAVAILABLE,

.descr = descr };

debug_print_object(&o, "active_state");

}

raw_spin_unlock_irqrestore(&db->lock, flags);

}

#ifdef CONFIG_DEBUG_OBJECTS_FREE

static void __debug_check_no_obj_freed(const void *address, unsigned long size)

{

unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;

struct hlist_node *tmp;

HLIST_HEAD(freelist);

struct debug_obj_descr *descr;

enum debug_obj_state state;

struct debug_bucket *db;

struct debug_obj *obj;

int cnt;

saddr = (unsigned long) address;

eaddr = saddr + size;

paddr = saddr & ODEBUG_CHUNK_MASK;

chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));

chunks >>= ODEBUG_CHUNK_SHIFT;

for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {

db = get_bucket(paddr);

repeat:

cnt = 0;

raw_spin_lock_irqsave(&db->lock, flags);

hlist_for_each_entry_safe(obj, tmp, &db->list, node) {

cnt++;

oaddr = (unsigned long) obj->object;

if (oaddr < saddr || oaddr >= eaddr)

continue;

switch (obj->state) {

case ODEBUG_STATE_ACTIVE:

debug_print_object(obj, "free");

descr = obj->descr;

state = obj->state;

raw_spin_unlock_irqrestore(&db->lock, flags);

debug_object_fixup(descr->fixup_free,

(void *) oaddr, state);

goto repeat;

default:

hlist_del(&obj->node);

hlist_add_head(&obj->node, &freelist);

break;

}

raw_spin_unlock_irqrestore(&db->lock, flags);

/* Now free them */

hlist_for_each_entry_safe(obj, tmp, &freelist, node) {

hlist_del(&obj->node);

free_object(obj);

}

if (cnt > debug_objects_maxchain)

debug_objects_maxchain = cnt;

}

void debug_check_no_obj_freed(const void *address, unsigned long size)

{

if (debug_objects_enabled)

__debug_check_no_obj_freed(address, size);

}

#endif

#ifdef CONFIG_DEBUG_FS

static int debug_stats_show(struct seq_file *m, void *v)

{

seq_printf(m, "max_chain :%d\n", debug_objects_maxchain);

seq_printf(m, "warnings :%d\n", debug_objects_warnings);

seq_printf(m, "fixups :%d\n", debug_objects_fixups);

seq_printf(m, "pool_free :%d\n", obj_pool_free);

seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);

seq_printf(m, "pool_used :%d\n", obj_pool_used);

seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);

return 0;

}

static int debug_stats_open(struct inode *inode, struct file *filp)

{

return single_open(filp, debug_stats_show, NULL);

}

static const struct file_operations debug_stats_fops = {

.open = debug_stats_open,

.read = seq_read,

.llseek = seq_lseek,

.release = single_release,

};

static int __init debug_objects_init_debugfs(void)

{

struct dentry *dbgdir, *dbgstats;

if (!debug_objects_enabled)

return 0;

dbgdir = debugfs_create_dir("debug_objects", NULL);

if (!dbgdir)

return -ENOMEM;

dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,

&debug_stats_fops);

if (!dbgstats)

goto err;

return 0;

err:

debugfs_remove(dbgdir);

return -ENOMEM;

}

__initcall(debug_objects_init_debugfs);

#else

static inline void debug_objects_init_debugfs(void) { }

#endif

#ifdef CONFIG_DEBUG_OBJECTS_SELFTEST

/* Random data structure for the self test */

struct self_test {

unsigned long dummy1[6];

int static_init;

unsigned long dummy2[3];

};

static __initdata struct debug_obj_descr descr_type_test;

* fixup_init is called when:

* - an active object is initialized

static int __init fixup_init(void *addr, enum debug_obj_state state)

{

struct self_test *obj = addr;

switch (state) {

case ODEBUG_STATE_ACTIVE:

debug_object_deactivate(obj, &descr_type_test);

debug_object_init(obj, &descr_type_test);

return 1;

default:

return 0;

}

* fixup_activate is called when:

* - an active object is activated

* - an unknown object is activated (might be a statically initialized object)

static int __init fixup_activate(void *addr, enum debug_obj_state state)

{

struct self_test *obj = addr;

switch (state) {

case ODEBUG_STATE_NOTAVAILABLE:

if (obj->static_init == 1) {

debug_object_init(obj, &descr_type_test);

debug_object_activate(obj, &descr_type_test);

return 0;

}

return 1;

case ODEBUG_STATE_ACTIVE:

debug_object_deactivate(obj, &descr_type_test);

debug_object_activate(obj, &descr_type_test);

return 1;

default:

return 0;

}

* fixup_destroy is called when:

* - an active object is destroyed

static int __init fixup_destroy(void *addr, enum debug_obj_state state)

{

struct self_test *obj = addr;

switch (state) {

case ODEBUG_STATE_ACTIVE:

debug_object_deactivate(obj, &descr_type_test);

debug_object_destroy(obj, &descr_type_test);

return 1;

default:

return 0;

}

* fixup_free is called when:

* - an active object is freed

static int __init fixup_free(void *addr, enum debug_obj_state state)

{

struct self_test *obj = addr;

switch (state) {

case ODEBUG_STATE_ACTIVE:

debug_object_deactivate(obj, &descr_type_test);

debug_object_free(obj, &descr_type_test);

return 1;

default:

return 0;

}

static int __init

check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)

{

struct debug_bucket *db;

struct debug_obj *obj;

unsigned long flags;

int res = -EINVAL;

db = get_bucket((unsigned long) addr);

raw_spin_lock_irqsave(&db->lock, flags);

obj = lookup_object(addr, db);

if (!obj && state != ODEBUG_STATE_NONE) {

WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");

goto out;

}

if (obj && obj->state != state) {

WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",

obj->state, state);

goto out;

}

if (fixups != debug_objects_fixups) {

WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",

fixups, debug_objects_fixups);

goto out;

}

if (warnings != debug_objects_warnings) {

WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",

warnings, debug_objects_warnings);

goto out;

}

res = 0;

out:

raw_spin_unlock_irqrestore(&db->lock, flags);

if (res)

debug_objects_enabled = 0;

return res;

}

static __initdata struct debug_obj_descr descr_type_test = {

.name = "selftest",

.fixup_init = fixup_init,

.fixup_activate = fixup_activate,

.fixup_destroy = fixup_destroy,

.fixup_free = fixup_free,

};

static __initdata struct self_test obj = { .static_init = 0 };

static void __init debug_objects_selftest(void)

{

int fixups, oldfixups, warnings, oldwarnings;

unsigned long flags;

local_irq_save(flags);

fixups = oldfixups = debug_objects_fixups;

warnings = oldwarnings = debug_objects_warnings;

descr_test = &descr_type_test;

debug_object_init(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))

goto out;

debug_object_activate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))

goto out;

debug_object_activate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))

goto out;

debug_object_deactivate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))

goto out;

debug_object_destroy(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))

goto out;

debug_object_init(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))

goto out;

debug_object_activate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))

goto out;

debug_object_deactivate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))

goto out;

debug_object_free(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))

goto out;

obj.static_init = 1;

debug_object_activate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))

goto out;

debug_object_init(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))

goto out;

debug_object_free(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))

goto out;

#ifdef CONFIG_DEBUG_OBJECTS_FREE

debug_object_init(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))

goto out;

debug_object_activate(&obj, &descr_type_test);

if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))

goto out;

__debug_check_no_obj_freed(&obj, sizeof(obj));

if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))

goto out;

#endif

printk(KERN_INFO "ODEBUG: selftest passed\n");

out:

debug_objects_fixups = oldfixups;

debug_objects_warnings = oldwarnings;

descr_test = NULL;

local_irq_restore(flags);

}

#else

static inline void debug_objects_selftest(void) { }

#endif

View remainder of file in raw view

linux/lib/debugobjects.c at master · rata/linux · GitHub

Expand file tree

Breadcrumbs

debugobjects.c

Latest commit

History

Breadcrumbs

debugobjects.c

File metadata and controls