cregit-Linux how code gets into the kernel

Release 4.8 lib/locking-selftest.c

Directory: lib
/*
 * lib/locking-selftest.c
 *
 * Testsuite for various locking APIs: spinlocks, rwlocks,
 * mutexes and rw-semaphores.
 *
 * It is checking both false positives and false negatives.
 *
 * Started by Ingo Molnar:
 *
 *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
 */
#include <linux/rwsem.h>
#include <linux/mutex.h>
#include <linux/ww_mutex.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/lockdep.h>
#include <linux/spinlock.h>
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
#include <linux/irqflags.h>

/*
 * Change this to 1 if you want to see the failure printouts:
 */

static unsigned int debug_locks_verbose;

static DEFINE_WW_CLASS(ww_lockdep);


static int __init setup_debug_locks_verbose(char *str) { get_option(&str, &debug_locks_verbose); return 1; }

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__setup("debug_locks_verbose=", setup_debug_locks_verbose); #define FAILURE 0 #define SUCCESS 1 #define LOCKTYPE_SPIN 0x1 #define LOCKTYPE_RWLOCK 0x2 #define LOCKTYPE_MUTEX 0x4 #define LOCKTYPE_RWSEM 0x8 #define LOCKTYPE_WW 0x10 static struct ww_acquire_ctx t, t2; static struct ww_mutex o, o2, o3; /* * Normal standalone locks, for the circular and irq-context * dependency tests: */ static DEFINE_RAW_SPINLOCK(lock_A); static DEFINE_RAW_SPINLOCK(lock_B); static DEFINE_RAW_SPINLOCK(lock_C); static DEFINE_RAW_SPINLOCK(lock_D); static DEFINE_RWLOCK(rwlock_A); static DEFINE_RWLOCK(rwlock_B); static DEFINE_RWLOCK(rwlock_C); static DEFINE_RWLOCK(rwlock_D); static DEFINE_MUTEX(mutex_A); static DEFINE_MUTEX(mutex_B); static DEFINE_MUTEX(mutex_C); static DEFINE_MUTEX(mutex_D); static DECLARE_RWSEM(rwsem_A); static DECLARE_RWSEM(rwsem_B); static DECLARE_RWSEM(rwsem_C); static DECLARE_RWSEM(rwsem_D); /* * Locks that we initialize dynamically as well so that * e.g. X1 and X2 becomes two instances of the same class, * but X* and Y* are different classes. We do this so that * we do not trigger a real lockup: */ static DEFINE_RAW_SPINLOCK(lock_X1); static DEFINE_RAW_SPINLOCK(lock_X2); static DEFINE_RAW_SPINLOCK(lock_Y1); static DEFINE_RAW_SPINLOCK(lock_Y2); static DEFINE_RAW_SPINLOCK(lock_Z1); static DEFINE_RAW_SPINLOCK(lock_Z2); static DEFINE_RWLOCK(rwlock_X1); static DEFINE_RWLOCK(rwlock_X2); static DEFINE_RWLOCK(rwlock_Y1); static DEFINE_RWLOCK(rwlock_Y2); static DEFINE_RWLOCK(rwlock_Z1); static DEFINE_RWLOCK(rwlock_Z2); static DEFINE_MUTEX(mutex_X1); static DEFINE_MUTEX(mutex_X2); static DEFINE_MUTEX(mutex_Y1); static DEFINE_MUTEX(mutex_Y2); static DEFINE_MUTEX(mutex_Z1); static DEFINE_MUTEX(mutex_Z2); static DECLARE_RWSEM(rwsem_X1); static DECLARE_RWSEM(rwsem_X2); static DECLARE_RWSEM(rwsem_Y1); static DECLARE_RWSEM(rwsem_Y2); static DECLARE_RWSEM(rwsem_Z1); static DECLARE_RWSEM(rwsem_Z2); /* * non-inlined runtime initializers, to let separate locks share * the same lock-class: */ #define INIT_CLASS_FUNC(class) \ static noinline void \ init_class_##class(raw_spinlock_t *lock, rwlock_t *rwlock, \ struct mutex *mutex, struct rw_semaphore *rwsem)\ { \ raw_spin_lock_init(lock); \ rwlock_init(rwlock); \ mutex_init(mutex); \ init_rwsem(rwsem); \ } INIT_CLASS_FUNC(X) INIT_CLASS_FUNC(Y) INIT_CLASS_FUNC(Z)
static void init_shared_classes(void) { init_class_X(&lock_X1, &rwlock_X1, &mutex_X1, &rwsem_X1); init_class_X(&lock_X2, &rwlock_X2, &mutex_X2, &rwsem_X2); init_class_Y(&lock_Y1, &rwlock_Y1, &mutex_Y1, &rwsem_Y1); init_class_Y(&lock_Y2, &rwlock_Y2, &mutex_Y2, &rwsem_Y2); init_class_Z(&lock_Z1, &rwlock_Z1, &mutex_Z1, &rwsem_Z1); init_class_Z(&lock_Z2, &rwlock_Z2, &mutex_Z2, &rwsem_Z2); }

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/* * For spinlocks and rwlocks we also do hardirq-safe / softirq-safe tests. * The following functions use a lock from a simulated hardirq/softirq * context, causing the locks to be marked as hardirq-safe/softirq-safe: */ #define HARDIRQ_DISABLE local_irq_disable #define HARDIRQ_ENABLE local_irq_enable #define HARDIRQ_ENTER() \ local_irq_disable(); \ __irq_enter(); \ WARN_ON(!in_irq()); #define HARDIRQ_EXIT() \ __irq_exit(); \ local_irq_enable(); #define SOFTIRQ_DISABLE local_bh_disable #define SOFTIRQ_ENABLE local_bh_enable #define SOFTIRQ_ENTER() \ local_bh_disable(); \ local_irq_disable(); \ lockdep_softirq_enter(); \ WARN_ON(!in_softirq()); #define SOFTIRQ_EXIT() \ lockdep_softirq_exit(); \ local_irq_enable(); \ local_bh_enable(); /* * Shortcuts for lock/unlock API variants, to keep * the testcases compact: */ #define L(x) raw_spin_lock(&lock_##x) #define U(x) raw_spin_unlock(&lock_##x) #define LU(x) L(x); U(x) #define SI(x) raw_spin_lock_init(&lock_##x) #define WL(x) write_lock(&rwlock_##x) #define WU(x) write_unlock(&rwlock_##x) #define WLU(x) WL(x); WU(x) #define RL(x) read_lock(&rwlock_##x) #define RU(x) read_unlock(&rwlock_##x) #define RLU(x) RL(x); RU(x) #define RWI(x) rwlock_init(&rwlock_##x) #define ML(x) mutex_lock(&mutex_##x) #define MU(x) mutex_unlock(&mutex_##x) #define MI(x) mutex_init(&mutex_##x) #define WSL(x) down_write(&rwsem_##x) #define WSU(x) up_write(&rwsem_##x) #define RSL(x) down_read(&rwsem_##x) #define RSU(x) up_read(&rwsem_##x) #define RWSI(x) init_rwsem(&rwsem_##x) #ifndef CONFIG_DEBUG_WW_MUTEX_SLOWPATH #define WWAI(x) ww_acquire_init(x, &ww_lockdep) #else #define WWAI(x) do { ww_acquire_init(x, &ww_lockdep); (x)->deadlock_inject_countdown = ~0U; } while (0) #endif #define WWAD(x) ww_acquire_done(x) #define WWAF(x) ww_acquire_fini(x) #define WWL(x, c) ww_mutex_lock(x, c) #define WWT(x) ww_mutex_trylock(x) #define WWL1(x) ww_mutex_lock(x, NULL) #define WWU(x) ww_mutex_unlock(x) #define LOCK_UNLOCK_2(x,y) LOCK(x); LOCK(y); UNLOCK(y); UNLOCK(x) /* * Generate different permutations of the same testcase, using * the same basic lock-dependency/state events: */ #define GENERATE_TESTCASE(name) \ \ static void name(void) { E(); } #define GENERATE_PERMUTATIONS_2_EVENTS(name) \ \ static void name##_12(void) { E1(); E2(); } \ static void name##_21(void) { E2(); E1(); } #define GENERATE_PERMUTATIONS_3_EVENTS(name) \ \ static void name##_123(void) { E1(); E2(); E3(); } \ static void name##_132(void) { E1(); E3(); E2(); } \ static void name##_213(void) { E2(); E1(); E3(); } \ static void name##_231(void) { E2(); E3(); E1(); } \ static void name##_312(void) { E3(); E1(); E2(); } \ static void name##_321(void) { E3(); E2(); E1(); } /* * AA deadlock: */ #define E() \ \ LOCK(X1); \ LOCK(X2); /* this one should fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(AA_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(AA_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(AA_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(AA_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(AA_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(AA_rsem) #undef E /* * Special-case for read-locking, they are * allowed to recurse on the same lock class: */
static void rlock_AA1(void) { RL(X1); RL(X1); // this one should NOT fail }

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static void rlock_AA1B(void) { RL(X1); RL(X2); // this one should NOT fail }

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static void rsem_AA1(void) { RSL(X1); RSL(X1); // this one should fail }

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static void rsem_AA1B(void) { RSL(X1); RSL(X2); // this one should fail }

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/* * The mixing of read and write locks is not allowed: */
static void rlock_AA2(void) { RL(X1); WL(X2); // this one should fail }

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static void rsem_AA2(void) { RSL(X1); WSL(X2); // this one should fail }

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static void rlock_AA3(void) { WL(X1); RL(X2); // this one should fail }

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static void rsem_AA3(void) { WSL(X1); RSL(X2); // this one should fail }

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/* * ABBA deadlock: */ #define E() \ \ LOCK_UNLOCK_2(A, B); \ LOCK_UNLOCK_2(B, A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(ABBA_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(ABBA_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(ABBA_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(ABBA_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(ABBA_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(ABBA_rsem) #undef E /* * AB BC CA deadlock: */ #define E() \ \ LOCK_UNLOCK_2(A, B); \ LOCK_UNLOCK_2(B, C); \ LOCK_UNLOCK_2(C, A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(ABBCCA_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(ABBCCA_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(ABBCCA_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(ABBCCA_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(ABBCCA_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(ABBCCA_rsem) #undef E /* * AB CA BC deadlock: */ #define E() \ \ LOCK_UNLOCK_2(A, B); \ LOCK_UNLOCK_2(C, A); \ LOCK_UNLOCK_2(B, C); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(ABCABC_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(ABCABC_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(ABCABC_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(ABCABC_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(ABCABC_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(ABCABC_rsem) #undef E /* * AB BC CD DA deadlock: */ #define E() \ \ LOCK_UNLOCK_2(A, B); \ LOCK_UNLOCK_2(B, C); \ LOCK_UNLOCK_2(C, D); \ LOCK_UNLOCK_2(D, A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(ABBCCDDA_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(ABBCCDDA_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(ABBCCDDA_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(ABBCCDDA_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(ABBCCDDA_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(ABBCCDDA_rsem) #undef E /* * AB CD BD DA deadlock: */ #define E() \ \ LOCK_UNLOCK_2(A, B); \ LOCK_UNLOCK_2(C, D); \ LOCK_UNLOCK_2(B, D); \ LOCK_UNLOCK_2(D, A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(ABCDBDDA_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(ABCDBDDA_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(ABCDBDDA_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(ABCDBDDA_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(ABCDBDDA_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(ABCDBDDA_rsem) #undef E /* * AB CD BC DA deadlock: */ #define E() \ \ LOCK_UNLOCK_2(A, B); \ LOCK_UNLOCK_2(C, D); \ LOCK_UNLOCK_2(B, C); \ LOCK_UNLOCK_2(D, A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(ABCDBCDA_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(ABCDBCDA_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(ABCDBCDA_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(ABCDBCDA_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(ABCDBCDA_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(ABCDBCDA_rsem) #undef E /* * Double unlock: */ #define E() \ \ LOCK(A); \ UNLOCK(A); \ UNLOCK(A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(double_unlock_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(double_unlock_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(double_unlock_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(double_unlock_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(double_unlock_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(double_unlock_rsem) #undef E /* * Bad unlock ordering: */ #define E() \ \ LOCK(A); \ LOCK(B); \ UNLOCK(A); /* fail */ \ UNLOCK(B); /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(bad_unlock_order_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(bad_unlock_order_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(bad_unlock_order_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(bad_unlock_order_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(bad_unlock_order_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(bad_unlock_order_rsem) #undef E /* * initializing a held lock: */ #define E() \ \ LOCK(A); \ INIT(A); /* fail */ /* * 6 testcases: */ #include "locking-selftest-spin.h" GENERATE_TESTCASE(init_held_spin) #include "locking-selftest-wlock.h" GENERATE_TESTCASE(init_held_wlock) #include "locking-selftest-rlock.h" GENERATE_TESTCASE(init_held_rlock) #include "locking-selftest-mutex.h" GENERATE_TESTCASE(init_held_mutex) #include "locking-selftest-wsem.h" GENERATE_TESTCASE(init_held_wsem) #include "locking-selftest-rsem.h" GENERATE_TESTCASE(init_held_rsem) #undef E /* * locking an irq-safe lock with irqs enabled: */ #define E1() \ \ IRQ_ENTER(); \ LOCK(A); \ UNLOCK(A); \ IRQ_EXIT(); #define E2() \ \ LOCK(A); \ UNLOCK(A); /* * Generate 24 testcases: */ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin) #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock) #include "locking-selftest-wlock-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_wlock) #include "locking-selftest-spin-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_spin) #include "locking-selftest-rlock-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_rlock) #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock) #undef E1 #undef E2 /* * Enabling hardirqs with a softirq-safe lock held: */ #define E1() \ \ SOFTIRQ_ENTER(); \ LOCK(A); \ UNLOCK(A); \ SOFTIRQ_EXIT(); #define E2() \ \ HARDIRQ_DISABLE(); \ LOCK(A); \ HARDIRQ_ENABLE(); \ UNLOCK(A); /* * Generate 12 testcases: */ #include "locking-selftest-spin.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_spin) #include "locking-selftest-wlock.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_wlock) #include "locking-selftest-rlock.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2A_rlock) #undef E1 #undef E2 /* * Enabling irqs with an irq-safe lock held: */ #define E1() \ \ IRQ_ENTER(); \ LOCK(A); \ UNLOCK(A); \ IRQ_EXIT(); #define E2() \ \ IRQ_DISABLE(); \ LOCK(A); \ IRQ_ENABLE(); \ UNLOCK(A); /* * Generate 24 testcases: */ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin) #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock) #include "locking-selftest-wlock-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_wlock) #include "locking-selftest-spin-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_spin) #include "locking-selftest-rlock-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_rlock) #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock) #undef E1 #undef E2 /* * Acquiring a irq-unsafe lock while holding an irq-safe-lock: */ #define E1() \ \ LOCK(A); \ LOCK(B); \ UNLOCK(B); \ UNLOCK(A); \ #define E2() \ \ LOCK(B); \ UNLOCK(B); #define E3() \ \ IRQ_ENTER(); \ LOCK(A); \ UNLOCK(A); \ IRQ_EXIT(); /* * Generate 36 testcases: */ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin) #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock) #include "locking-selftest-wlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_wlock) #include "locking-selftest-spin-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_spin) #include "locking-selftest-rlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_rlock) #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock) #undef E1 #undef E2 #undef E3 /* * If a lock turns into softirq-safe, but earlier it took * a softirq-unsafe lock: */ #define E1() \ IRQ_DISABLE(); \ LOCK(A); \ LOCK(B); \ UNLOCK(B); \ UNLOCK(A); \ IRQ_ENABLE(); #define E2() \ LOCK(B); \ UNLOCK(B); #define E3() \ IRQ_ENTER(); \ LOCK(A); \ UNLOCK(A); \ IRQ_EXIT(); /* * Generate 36 testcases: */ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin) #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock) #include "locking-selftest-wlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_wlock) #include "locking-selftest-spin-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_spin) #include "locking-selftest-rlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_rlock) #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock) #undef E1 #undef E2 #undef E3 /* * read-lock / write-lock irq inversion. * * Deadlock scenario: * * CPU#1 is at #1, i.e. it has write-locked A, but has not * taken B yet. * * CPU#2 is at #2, i.e. it has locked B. * * Hardirq hits CPU#2 at point #2 and is trying to read-lock A. * * The deadlock occurs because CPU#1 will spin on B, and CPU#2 * will spin on A. */ #define E1() \ \ IRQ_DISABLE(); \ WL(A); \ LOCK(B); \ UNLOCK(B); \ WU(A); \ IRQ_ENABLE(); #define E2() \ \ LOCK(B); \ UNLOCK(B); #define E3() \ \ IRQ_ENTER(); \ RL(A); \ RU(A); \ IRQ_EXIT(); /* * Generate 36 testcases: */ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_spin) #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_rlock) #include "locking-selftest-wlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_hard_wlock) #include "locking-selftest-spin-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_spin) #include "locking-selftest-rlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_rlock) #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_inversion_soft_wlock) #undef E1 #undef E2 #undef E3 /* * read-lock / write-lock recursion that is actually safe. */ #define E1() \ \ IRQ_DISABLE(); \ WL(A); \ WU(A); \ IRQ_ENABLE(); #define E2() \ \ RL(A); \ RU(A); \ #define E3() \ \ IRQ_ENTER(); \ RL(A); \ L(B); \ U(B); \ RU(A); \ IRQ_EXIT(); /* * Generate 12 testcases: */ #include "locking-selftest-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_hard) #include "locking-selftest-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft) #undef E1 #undef E2 #undef E3 /* * read-lock / write-lock recursion that is unsafe. */ #define E1() \ \ IRQ_DISABLE(); \ L(B); \ WL(A); \ WU(A); \ U(B); \ IRQ_ENABLE(); #define E2() \ \ RL(A); \ RU(A); \ #define E3() \ \ IRQ_ENTER(); \ L(B); \ U(B); \ IRQ_EXIT(); /* * Generate 12 testcases: */ #include "locking-selftest-hardirq.h" // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_hard) #include "locking-selftest-softirq.h" // GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion2_soft) #ifdef CONFIG_DEBUG_LOCK_ALLOC # define I_SPINLOCK(x) lockdep_reset_lock(&lock_##x.dep_map) # define I_RWLOCK(x) lockdep_reset_lock(&rwlock_##x.dep_map) # define I_MUTEX(x) lockdep_reset_lock(&mutex_##x.dep_map) # define I_RWSEM(x) lockdep_reset_lock(&rwsem_##x.dep_map) # define I_WW(x) lockdep_reset_lock(&x.dep_map) #else # define I_SPINLOCK(x) # define I_RWLOCK(x) # define I_MUTEX(x) # define I_RWSEM(x) # define I_WW(x) #endif #define I1(x) \ do { \ I_SPINLOCK(x); \ I_RWLOCK(x); \ I_MUTEX(x); \ I_RWSEM(x); \ } while (0) #define I2(x) \ do { \ raw_spin_lock_init(&lock_##x); \ rwlock_init(&rwlock_##x); \ mutex_init(&mutex_##x); \ init_rwsem(&rwsem_##x); \ } while (0)
static void reset_locks(void) { local_irq_disable(); lockdep_free_key_range(&ww_lockdep.acquire_key, 1); lockdep_free_key_range(&ww_lockdep.mutex_key, 1); I1(A); I1(B); I1(C); I1(D); I1(X1); I1(X2); I1(Y1); I1(Y2); I1(Z1); I1(Z2); I_WW(t); I_WW(t2); I_WW(o.base); I_WW(o2.base); I_WW(o3.base); lockdep_reset(); I2(A); I2(B); I2(C); I2(D); init_shared_classes(); ww_mutex_init(&o, &ww_lockdep); ww_mutex_init(&o2, &ww_lockdep); ww_mutex_init(&o3, &ww_lockdep); memset(&t, 0, sizeof(t)); memset(&t2, 0, sizeof(t2)); memset(&ww_lockdep.acquire_key, 0, sizeof(ww_lockdep.acquire_key)); memset(&ww_lockdep.mutex_key, 0, sizeof(ww_lockdep.mutex_key)); local_irq_enable(); }

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ingo molnaringo molnar9039.47%133.33%
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#undef I static int testcase_total; static int testcase_successes; static int expected_testcase_failures; static int unexpected_testcase_failures;
static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask) { unsigned long saved_preempt_count = preempt_count(); WARN_ON(irqs_disabled()); testcase_fn(); /* * Filter out expected failures: */ #ifndef CONFIG_PROVE_LOCKING if (expected == FAILURE && debug_locks) { expected_testcase_failures++; printk("failed|"); } else #endif if (debug_locks != expected) { unexpected_testcase_failures++; printk("FAILED|"); dump_stack(); } else { testcase_successes++; printk(" ok |"); } testcase_total++; if (debug_locks_verbose) printk(" lockclass mask: %x, debug_locks: %d, expected: %d\n", lockclass_mask, debug_locks, expected); /* * Some tests (e.g. double-unlock) might corrupt the preemption * count, so restore it: */ preempt_count_set(saved_preempt_count); #ifdef CONFIG_TRACE_IRQFLAGS if (softirq_count()) current->softirqs_enabled = 0; else current->softirqs_enabled = 1; #endif reset_locks(); }

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static inline void print_testname(const char *testname) { printk("%33s:", testname); }

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#define DO_TESTCASE_1(desc, name, nr) \ print_testname(desc"/"#nr); \ dotest(name##_##nr, SUCCESS, LOCKTYPE_RWLOCK); \ printk("\n"); #define DO_TESTCASE_1B(desc, name, nr) \ print_testname(desc"/"#nr); \ dotest(name##_##nr, FAILURE, LOCKTYPE_RWLOCK); \ printk("\n"); #define DO_TESTCASE_3(desc, name, nr) \ print_testname(desc"/"#nr); \ dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN); \ dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \ dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \ printk("\n"); #define DO_TESTCASE_3RW(desc, name, nr) \ print_testname(desc"/"#nr); \ dotest(name##_spin_##nr, FAILURE, LOCKTYPE_SPIN|LOCKTYPE_RWLOCK);\ dotest(name##_wlock_##nr, FAILURE, LOCKTYPE_RWLOCK); \ dotest(name##_rlock_##nr, SUCCESS, LOCKTYPE_RWLOCK); \ printk("\n"); #define DO_TESTCASE_6(desc, name) \ print_testname(desc); \ dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \ dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \ dotest(name##_rlock, FAILURE, LOCKTYPE_RWLOCK); \ dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \ dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \ dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \ printk("\n"); #define DO_TESTCASE_6_SUCCESS(desc, name) \ print_testname(desc); \ dotest(name##_spin, SUCCESS, LOCKTYPE_SPIN); \ dotest(name##_wlock, SUCCESS, LOCKTYPE_RWLOCK); \ dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \ dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX); \ dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM); \ dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM); \ printk("\n"); /* * 'read' variant: rlocks must not trigger. */ #define DO_TESTCASE_6R(desc, name) \ print_testname(desc); \ dotest(name##_spin, FAILURE, LOCKTYPE_SPIN); \ dotest(name##_wlock, FAILURE, LOCKTYPE_RWLOCK); \ dotest(name##_rlock, SUCCESS, LOCKTYPE_RWLOCK); \ dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX); \ dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM); \ dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM); \ printk("\n"); #define DO_TESTCASE_2I(desc, name, nr) \ DO_TESTCASE_1("hard-"desc, name##_hard, nr); \ DO_TESTCASE_1("soft-"desc, name##_soft, nr); #define DO_TESTCASE_2IB(desc, name, nr) \ DO_TESTCASE_1B("hard-"desc, name##_hard, nr); \ DO_TESTCASE_1B("soft-"desc, name##_soft, nr); #define DO_TESTCASE_6I(desc, name, nr) \ DO_TESTCASE_3("hard-"desc, name##_hard, nr); \ DO_TESTCASE_3("soft-"desc, name##_soft, nr); #define DO_TESTCASE_6IRW(desc, name, nr) \ DO_TESTCASE_3RW("hard-"desc, name##_hard, nr); \ DO_TESTCASE_3RW("soft-"desc, name##_soft, nr); #define DO_TESTCASE_2x3(desc, name) \ DO_TESTCASE_3(desc, name, 12); \ DO_TESTCASE_3(desc, name, 21); #define DO_TESTCASE_2x6(desc, name) \ DO_TESTCASE_6I(desc, name, 12); \ DO_TESTCASE_6I(desc, name, 21); #define DO_TESTCASE_6x2(desc, name) \ DO_TESTCASE_2I(desc, name, 123); \ DO_TESTCASE_2I(desc, name, 132); \ DO_TESTCASE_2I(desc, name, 213); \ DO_TESTCASE_2I(desc, name, 231); \ DO_TESTCASE_2I(desc, name, 312); \ DO_TESTCASE_2I(desc, name, 321); #define DO_TESTCASE_6x2B(desc, name) \ DO_TESTCASE_2IB(desc, name, 123); \ DO_TESTCASE_2IB(desc, name, 132); \ DO_TESTCASE_2IB(desc, name, 213); \ DO_TESTCASE_2IB(desc, name, 231); \ DO_TESTCASE_2IB(desc, name, 312); \ DO_TESTCASE_2IB(desc, name, 321); #define DO_TESTCASE_6x6(desc, name) \ DO_TESTCASE_6I(desc, name, 123); \ DO_TESTCASE_6I(desc, name, 132); \ DO_TESTCASE_6I(desc, name, 213); \ DO_TESTCASE_6I(desc, name, 231); \ DO_TESTCASE_6I(desc, name, 312); \ DO_TESTCASE_6I(desc, name, 321); #define DO_TESTCASE_6x6RW(desc, name) \ DO_TESTCASE_6IRW(desc, name, 123); \ DO_TESTCASE_6IRW(desc, name, 132); \ DO_TESTCASE_6IRW(desc, name, 213); \ DO_TESTCASE_6IRW(desc, name, 231); \ DO_TESTCASE_6IRW(desc, name, 312); \ DO_TESTCASE_6IRW(desc, name, 321);
static void ww_test_fail_acquire(void) { int ret; WWAI(&t); t.stamp++; ret = WWL(&o, &t); if (WARN_ON(!o.ctx) || WARN_ON(ret)) return; /* No lockdep test, pure API */ ret = WWL(&o, &t); WARN_ON(ret != -EALREADY); ret = WWT(&o); WARN_ON(ret); t2 = t; t2.stamp++; ret = WWL(&o, &t2); WARN_ON(ret != -EDEADLK); WWU(&o); if (WWT(&o)) WWU(&o); #ifdef CONFIG_DEBUG_LOCK_ALLOC else DEBUG_LOCKS_WARN_ON(1); #endif }

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static void ww_test_normal(void) { int ret; WWAI(&t); /* * None of the ww_mutex codepaths should be taken in the 'normal' * mutex calls. The easiest way to verify this is by using the * normal mutex calls, and making sure o.ctx is unmodified. */ /* mutex_lock (and indirectly, mutex_lock_nested) */ o.ctx = (void *)~0UL; mutex_lock(&o.base); mutex_unlock(&o.base); WARN_ON(o.ctx != (void *)~0UL); /* mutex_lock_interruptible (and *_nested) */ o.ctx = (void *)~0UL; ret = mutex_lock_interruptible(&o.base); if (!ret) mutex_unlock(&o.base); else WARN_ON(1); WARN_ON(o.ctx != (void *)~0UL); /* mutex_lock_killable (and *_nested) */ o.ctx = (void *)~0UL; ret = mutex_lock_killable(&o.base); if (!ret) mutex_unlock(&o.base); else WARN_ON(1); WARN_ON(o.ctx != (void *)~