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| -rw-r--r-- | tools/testing/selftests/futex/include/futextest.h | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/tools/testing/selftests/futex/include/futextest.h b/tools/testing/selftests/futex/include/futextest.h new file mode 100644 index 000000000..b98c3aba7 --- /dev/null +++ b/tools/testing/selftests/futex/include/futextest.h @@ -0,0 +1,266 @@ +/****************************************************************************** + * + * Copyright © International Business Machines Corp., 2009 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * DESCRIPTION + * Glibc independent futex library for testing kernel functionality. + * + * AUTHOR + * Darren Hart <dvhart@linux.intel.com> + * + * HISTORY + * 2009-Nov-6: Initial version by Darren Hart <dvhart@linux.intel.com> + * + *****************************************************************************/ + +#ifndef _FUTEXTEST_H +#define _FUTEXTEST_H + +#include <unistd.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <linux/futex.h> + +typedef volatile u_int32_t futex_t; +#define FUTEX_INITIALIZER 0 + +/* Define the newer op codes if the system header file is not up to date. */ +#ifndef FUTEX_WAIT_BITSET +#define FUTEX_WAIT_BITSET 9 +#endif +#ifndef FUTEX_WAKE_BITSET +#define FUTEX_WAKE_BITSET 10 +#endif +#ifndef FUTEX_WAIT_REQUEUE_PI +#define FUTEX_WAIT_REQUEUE_PI 11 +#endif +#ifndef FUTEX_CMP_REQUEUE_PI +#define FUTEX_CMP_REQUEUE_PI 12 +#endif +#ifndef FUTEX_WAIT_REQUEUE_PI_PRIVATE +#define FUTEX_WAIT_REQUEUE_PI_PRIVATE (FUTEX_WAIT_REQUEUE_PI | \ + FUTEX_PRIVATE_FLAG) +#endif +#ifndef FUTEX_REQUEUE_PI_PRIVATE +#define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \ + FUTEX_PRIVATE_FLAG) +#endif + +/** + * futex() - SYS_futex syscall wrapper + * @uaddr: address of first futex + * @op: futex op code + * @val: typically expected value of uaddr, but varies by op + * @timeout: typically an absolute struct timespec (except where noted + * otherwise). Overloaded by some ops + * @uaddr2: address of second futex for some ops\ + * @val3: varies by op + * @opflags: flags to be bitwise OR'd with op, such as FUTEX_PRIVATE_FLAG + * + * futex() is used by all the following futex op wrappers. It can also be + * used for misuse and abuse testing. Generally, the specific op wrappers + * should be used instead. It is a macro instead of an static inline function as + * some of the types over overloaded (timeout is used for nr_requeue for + * example). + * + * These argument descriptions are the defaults for all + * like-named arguments in the following wrappers except where noted below. + */ +#define futex(uaddr, op, val, timeout, uaddr2, val3, opflags) \ + syscall(SYS_futex, uaddr, op | opflags, val, timeout, uaddr2, val3) + +/** + * futex_wait() - block on uaddr with optional timeout + * @timeout: relative timeout + */ +static inline int +futex_wait(futex_t *uaddr, futex_t val, struct timespec *timeout, int opflags) +{ + return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags); +} + +/** + * futex_wake() - wake one or more tasks blocked on uaddr + * @nr_wake: wake up to this many tasks + */ +static inline int +futex_wake(futex_t *uaddr, int nr_wake, int opflags) +{ + return futex(uaddr, FUTEX_WAKE, nr_wake, NULL, NULL, 0, opflags); +} + +/** + * futex_wait_bitset() - block on uaddr with bitset + * @bitset: bitset to be used with futex_wake_bitset + */ +static inline int +futex_wait_bitset(futex_t *uaddr, futex_t val, struct timespec *timeout, + u_int32_t bitset, int opflags) +{ + return futex(uaddr, FUTEX_WAIT_BITSET, val, timeout, NULL, bitset, + opflags); +} + +/** + * futex_wake_bitset() - wake one or more tasks blocked on uaddr with bitset + * @bitset: bitset to compare with that used in futex_wait_bitset + */ +static inline int +futex_wake_bitset(futex_t *uaddr, int nr_wake, u_int32_t bitset, int opflags) +{ + return futex(uaddr, FUTEX_WAKE_BITSET, nr_wake, NULL, NULL, bitset, + opflags); +} + +/** + * futex_lock_pi() - block on uaddr as a PI mutex + * @detect: whether (1) or not (0) to perform deadlock detection + */ +static inline int +futex_lock_pi(futex_t *uaddr, struct timespec *timeout, int detect, + int opflags) +{ + return futex(uaddr, FUTEX_LOCK_PI, detect, timeout, NULL, 0, opflags); +} + +/** + * futex_unlock_pi() - release uaddr as a PI mutex, waking the top waiter + */ +static inline int +futex_unlock_pi(futex_t *uaddr, int opflags) +{ + return futex(uaddr, FUTEX_UNLOCK_PI, 0, NULL, NULL, 0, opflags); +} + +/** + * futex_wake_op() - FIXME: COME UP WITH A GOOD ONE LINE DESCRIPTION + */ +static inline int +futex_wake_op(futex_t *uaddr, futex_t *uaddr2, int nr_wake, int nr_wake2, + int wake_op, int opflags) +{ + return futex(uaddr, FUTEX_WAKE_OP, nr_wake, nr_wake2, uaddr2, wake_op, + opflags); +} + +/** + * futex_requeue() - requeue without expected value comparison, deprecated + * @nr_wake: wake up to this many tasks + * @nr_requeue: requeue up to this many tasks + * + * Due to its inherently racy implementation, futex_requeue() is deprecated in + * favor of futex_cmp_requeue(). + */ +static inline int +futex_requeue(futex_t *uaddr, futex_t *uaddr2, int nr_wake, int nr_requeue, + int opflags) +{ + return futex(uaddr, FUTEX_REQUEUE, nr_wake, nr_requeue, uaddr2, 0, + opflags); +} + +/** + * futex_cmp_requeue() - requeue tasks from uaddr to uaddr2 + * @nr_wake: wake up to this many tasks + * @nr_requeue: requeue up to this many tasks + */ +static inline int +futex_cmp_requeue(futex_t *uaddr, futex_t val, futex_t *uaddr2, int nr_wake, + int nr_requeue, int opflags) +{ + return futex(uaddr, FUTEX_CMP_REQUEUE, nr_wake, nr_requeue, uaddr2, + val, opflags); +} + +/** + * futex_wait_requeue_pi() - block on uaddr and prepare to requeue to uaddr2 + * @uaddr: non-PI futex source + * @uaddr2: PI futex target + * + * This is the first half of the requeue_pi mechanism. It shall always be + * paired with futex_cmp_requeue_pi(). + */ +static inline int +futex_wait_requeue_pi(futex_t *uaddr, futex_t val, futex_t *uaddr2, + struct timespec *timeout, int opflags) +{ + return futex(uaddr, FUTEX_WAIT_REQUEUE_PI, val, timeout, uaddr2, 0, + opflags); +} + +/** + * futex_cmp_requeue_pi() - requeue tasks from uaddr to uaddr2 (PI aware) + * @uaddr: non-PI futex source + * @uaddr2: PI futex target + * @nr_wake: wake up to this many tasks + * @nr_requeue: requeue up to this many tasks + */ +static inline int +futex_cmp_requeue_pi(futex_t *uaddr, futex_t val, futex_t *uaddr2, int nr_wake, + int nr_requeue, int opflags) +{ + return futex(uaddr, FUTEX_CMP_REQUEUE_PI, nr_wake, nr_requeue, uaddr2, + val, opflags); +} + +/** + * futex_cmpxchg() - atomic compare and exchange + * @uaddr: The address of the futex to be modified + * @oldval: The expected value of the futex + * @newval: The new value to try and assign the futex + * + * Implement cmpxchg using gcc atomic builtins. + * http://gcc.gnu.org/onlinedocs/gcc-4.1.0/gcc/Atomic-Builtins.html + * + * Return the old futex value. + */ +static inline u_int32_t +futex_cmpxchg(futex_t *uaddr, u_int32_t oldval, u_int32_t newval) +{ + return __sync_val_compare_and_swap(uaddr, oldval, newval); +} + +/** + * futex_dec() - atomic decrement of the futex value + * @uaddr: The address of the futex to be modified + * + * Return the new futex value. + */ +static inline u_int32_t +futex_dec(futex_t *uaddr) +{ + return __sync_sub_and_fetch(uaddr, 1); +} + +/** + * futex_inc() - atomic increment of the futex value + * @uaddr: the address of the futex to be modified + * + * Return the new futex value. + */ +static inline u_int32_t +futex_inc(futex_t *uaddr) +{ + return __sync_add_and_fetch(uaddr, 1); +} + +/** + * futex_set() - atomic decrement of the futex value + * @uaddr: the address of the futex to be modified + * @newval: New value for the atomic_t + * + * Return the new futex value. + */ +static inline u_int32_t +futex_set(futex_t *uaddr, u_int32_t newval) +{ + *uaddr = newval; + return newval; +} + +#endif |