diff options
Diffstat (limited to 'kernel/futex')
| -rw-r--r-- | kernel/futex/core.c | 35 | ||||
| -rw-r--r-- | kernel/futex/futex.h | 6 | ||||
| -rw-r--r-- | kernel/futex/syscalls.c | 22 |
3 files changed, 0 insertions, 63 deletions
diff --git a/kernel/futex/core.c b/kernel/futex/core.c index 25d8a88b32e5..926c2bb752bc 100644 --- a/kernel/futex/core.c +++ b/kernel/futex/core.c @@ -41,11 +41,6 @@ #include "futex.h" #include "../locking/rtmutex_common.h" -#ifndef CONFIG_HAVE_FUTEX_CMPXCHG -int __read_mostly futex_cmpxchg_enabled; -#endif - - /* * The base of the bucket array and its size are always used together * (after initialization only in futex_hash()), so ensure that they @@ -776,9 +771,6 @@ static void exit_robust_list(struct task_struct *curr) unsigned long futex_offset; int rc; - if (!futex_cmpxchg_enabled) - return; - /* * Fetch the list head (which was registered earlier, via * sys_set_robust_list()): @@ -874,9 +866,6 @@ static void compat_exit_robust_list(struct task_struct *curr) compat_long_t futex_offset; int rc; - if (!futex_cmpxchg_enabled) - return; - /* * Fetch the list head (which was registered earlier, via * sys_set_robust_list()): @@ -950,8 +939,6 @@ static void exit_pi_state_list(struct task_struct *curr) struct futex_hash_bucket *hb; union futex_key key = FUTEX_KEY_INIT; - if (!futex_cmpxchg_enabled) - return; /* * We are a ZOMBIE and nobody can enqueue itself on * pi_state_list anymore, but we have to be careful @@ -1125,26 +1112,6 @@ void futex_exit_release(struct task_struct *tsk) futex_cleanup_end(tsk, FUTEX_STATE_DEAD); } -static void __init futex_detect_cmpxchg(void) -{ -#ifndef CONFIG_HAVE_FUTEX_CMPXCHG - u32 curval; - - /* - * This will fail and we want it. Some arch implementations do - * runtime detection of the futex_atomic_cmpxchg_inatomic() - * functionality. We want to know that before we call in any - * of the complex code paths. Also we want to prevent - * registration of robust lists in that case. NULL is - * guaranteed to fault and we get -EFAULT on functional - * implementation, the non-functional ones will return - * -ENOSYS. - */ - if (futex_cmpxchg_value_locked(&curval, NULL, 0, 0) == -EFAULT) - futex_cmpxchg_enabled = 1; -#endif -} - static int __init futex_init(void) { unsigned int futex_shift; @@ -1163,8 +1130,6 @@ static int __init futex_init(void) futex_hashsize, futex_hashsize); futex_hashsize = 1UL << futex_shift; - futex_detect_cmpxchg(); - for (i = 0; i < futex_hashsize; i++) { atomic_set(&futex_queues[i].waiters, 0); plist_head_init(&futex_queues[i].chain); diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index 040ae4277cb0..c264cbeab71c 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -27,12 +27,6 @@ #define FLAGS_CLOCKRT 0x02 #define FLAGS_HAS_TIMEOUT 0x04 -#ifdef CONFIG_HAVE_FUTEX_CMPXCHG -#define futex_cmpxchg_enabled 1 -#else -extern int __read_mostly futex_cmpxchg_enabled; -#endif - #ifdef CONFIG_FAIL_FUTEX extern bool should_fail_futex(bool fshared); #else diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index 6f91a07a6a83..086a22d1adb7 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -29,8 +29,6 @@ SYSCALL_DEFINE2(set_robust_list, struct robust_list_head __user *, head, size_t, len) { - if (!futex_cmpxchg_enabled) - return -ENOSYS; /* * The kernel knows only one size for now: */ @@ -56,9 +54,6 @@ SYSCALL_DEFINE3(get_robust_list, int, pid, unsigned long ret; struct task_struct *p; - if (!futex_cmpxchg_enabled) - return -ENOSYS; - rcu_read_lock(); ret = -ESRCH; @@ -104,17 +99,6 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, } switch (cmd) { - case FUTEX_LOCK_PI: - case FUTEX_LOCK_PI2: - case FUTEX_UNLOCK_PI: - case FUTEX_TRYLOCK_PI: - case FUTEX_WAIT_REQUEUE_PI: - case FUTEX_CMP_REQUEUE_PI: - if (!futex_cmpxchg_enabled) - return -ENOSYS; - } - - switch (cmd) { case FUTEX_WAIT: val3 = FUTEX_BITSET_MATCH_ANY; fallthrough; @@ -323,9 +307,6 @@ COMPAT_SYSCALL_DEFINE2(set_robust_list, struct compat_robust_list_head __user *, head, compat_size_t, len) { - if (!futex_cmpxchg_enabled) - return -ENOSYS; - if (unlikely(len != sizeof(*head))) return -EINVAL; @@ -342,9 +323,6 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid, unsigned long ret; struct task_struct *p; - if (!futex_cmpxchg_enabled) - return -ENOSYS; - rcu_read_lock(); ret = -ESRCH; |