diff options
Diffstat (limited to 'arch/tile/lib/atomic_32.c')
| -rw-r--r-- | arch/tile/lib/atomic_32.c | 90 |
1 files changed, 0 insertions, 90 deletions
diff --git a/arch/tile/lib/atomic_32.c b/arch/tile/lib/atomic_32.c index 42eacb1..5d91d18 100644 --- a/arch/tile/lib/atomic_32.c +++ b/arch/tile/lib/atomic_32.c @@ -20,50 +20,12 @@ #include <linux/atomic.h> #include <arch/chip.h> -/* See <asm/atomic_32.h> */ -#if ATOMIC_LOCKS_FOUND_VIA_TABLE() - -/* - * A block of memory containing locks for atomic ops. Each instance of this - * struct will be homed on a different CPU. - */ -struct atomic_locks_on_cpu { - int lock[ATOMIC_HASH_L2_SIZE]; -} __attribute__((aligned(ATOMIC_HASH_L2_SIZE * 4))); - -static DEFINE_PER_CPU(struct atomic_locks_on_cpu, atomic_lock_pool); - -/* The locks we'll use until __init_atomic_per_cpu is called. */ -static struct atomic_locks_on_cpu __initdata initial_atomic_locks; - -/* Hash into this vector to get a pointer to lock for the given atomic. */ -struct atomic_locks_on_cpu *atomic_lock_ptr[ATOMIC_HASH_L1_SIZE] - __write_once = { - [0 ... ATOMIC_HASH_L1_SIZE-1] (&initial_atomic_locks) -}; - -#else /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ - /* This page is remapped on startup to be hash-for-home. */ int atomic_locks[PAGE_SIZE / sizeof(int)] __page_aligned_bss; -#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ - int *__atomic_hashed_lock(volatile void *v) { /* NOTE: this code must match "sys_cmpxchg" in kernel/intvec_32.S */ -#if ATOMIC_LOCKS_FOUND_VIA_TABLE() - unsigned long i = - (unsigned long) v & ((PAGE_SIZE-1) & -sizeof(long long)); - unsigned long n = __insn_crc32_32(0, i); - - /* Grab high bits for L1 index. */ - unsigned long l1_index = n >> ((sizeof(n) * 8) - ATOMIC_HASH_L1_SHIFT); - /* Grab low bits for L2 index. */ - unsigned long l2_index = n & (ATOMIC_HASH_L2_SIZE - 1); - - return &atomic_lock_ptr[l1_index]->lock[l2_index]; -#else /* * Use bits [3, 3 + ATOMIC_HASH_SHIFT) as the lock index. * Using mm works here because atomic_locks is page aligned. @@ -72,26 +34,13 @@ int *__atomic_hashed_lock(volatile void *v) (unsigned long)atomic_locks, 2, (ATOMIC_HASH_SHIFT + 2) - 1); return (int *)ptr; -#endif } #ifdef CONFIG_SMP /* Return whether the passed pointer is a valid atomic lock pointer. */ static int is_atomic_lock(int *p) { -#if ATOMIC_LOCKS_FOUND_VIA_TABLE() - int i; - for (i = 0; i < ATOMIC_HASH_L1_SIZE; ++i) { - - if (p >= &atomic_lock_ptr[i]->lock[0] && - p < &atomic_lock_ptr[i]->lock[ATOMIC_HASH_L2_SIZE]) { - return 1; - } - } - return 0; -#else return p >= &atomic_locks[0] && p < &atomic_locks[ATOMIC_HASH_SIZE]; -#endif } void __atomic_fault_unlock(int *irqlock_word) @@ -210,43 +159,6 @@ struct __get_user __atomic_bad_address(int __user *addr) void __init __init_atomic_per_cpu(void) { -#if ATOMIC_LOCKS_FOUND_VIA_TABLE() - - unsigned int i; - int actual_cpu; - - /* - * Before this is called from setup, we just have one lock for - * all atomic objects/operations. Here we replace the - * elements of atomic_lock_ptr so that they point at per_cpu - * integers. This seemingly over-complex approach stems from - * the fact that DEFINE_PER_CPU defines an entry for each cpu - * in the grid, not each cpu from 0..ATOMIC_HASH_SIZE-1. But - * for efficient hashing of atomics to their locks we want a - * compile time constant power of 2 for the size of this - * table, so we use ATOMIC_HASH_SIZE. - * - * Here we populate atomic_lock_ptr from the per cpu - * atomic_lock_pool, interspersing by actual cpu so that - * subsequent elements are homed on consecutive cpus. - */ - - actual_cpu = cpumask_first(cpu_possible_mask); - - for (i = 0; i < ATOMIC_HASH_L1_SIZE; ++i) { - /* - * Preincrement to slightly bias against using cpu 0, - * which has plenty of stuff homed on it already. - */ - actual_cpu = cpumask_next(actual_cpu, cpu_possible_mask); - if (actual_cpu >= nr_cpu_ids) - actual_cpu = cpumask_first(cpu_possible_mask); - - atomic_lock_ptr[i] = &per_cpu(atomic_lock_pool, actual_cpu); - } - -#else /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ - /* Validate power-of-two and "bigger than cpus" assumption */ BUILD_BUG_ON(ATOMIC_HASH_SIZE & (ATOMIC_HASH_SIZE-1)); BUG_ON(ATOMIC_HASH_SIZE < nr_cpu_ids); @@ -270,6 +182,4 @@ void __init __init_atomic_per_cpu(void) * That should not produce more indices than ATOMIC_HASH_SIZE. */ BUILD_BUG_ON((PAGE_SIZE >> 3) > ATOMIC_HASH_SIZE); - -#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ } |
