diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/tile/kernel/setup.c | 2 | ||||
| -rw-r--r-- | arch/tile/lib/memchr_32.c | 35 | ||||
| -rw-r--r-- | arch/tile/lib/spinlock_32.c | 29 |
3 files changed, 38 insertions, 28 deletions
diff --git a/arch/tile/kernel/setup.c b/arch/tile/kernel/setup.c index fb0b3cb..f185736 100644 --- a/arch/tile/kernel/setup.c +++ b/arch/tile/kernel/setup.c @@ -840,7 +840,7 @@ static int __init topology_init(void) for_each_online_node(i) register_one_node(i); - for_each_present_cpu(i) + for (i = 0; i < smp_height * smp_width; ++i) register_cpu(&cpu_devices[i], i); return 0; diff --git a/arch/tile/lib/memchr_32.c b/arch/tile/lib/memchr_32.c index 6235283..cc3d9ba 100644 --- a/arch/tile/lib/memchr_32.c +++ b/arch/tile/lib/memchr_32.c @@ -18,12 +18,24 @@ void *memchr(const void *s, int c, size_t n) { + const uint32_t *last_word_ptr; + const uint32_t *p; + const char *last_byte_ptr; + uintptr_t s_int; + uint32_t goal, before_mask, v, bits; + char *ret; + + if (__builtin_expect(n == 0, 0)) { + /* Don't dereference any memory if the array is empty. */ + return NULL; + } + /* Get an aligned pointer. */ - const uintptr_t s_int = (uintptr_t) s; - const uint32_t *p = (const uint32_t *)(s_int & -4); + s_int = (uintptr_t) s; + p = (const uint32_t *)(s_int & -4); /* Create four copies of the byte for which we are looking. */ - const uint32_t goal = 0x01010101 * (uint8_t) c; + goal = 0x01010101 * (uint8_t) c; /* Read the first word, but munge it so that bytes before the array * will not match goal. @@ -31,23 +43,14 @@ void *memchr(const void *s, int c, size_t n) * Note that this shift count expression works because we know * shift counts are taken mod 32. */ - const uint32_t before_mask = (1 << (s_int << 3)) - 1; - uint32_t v = (*p | before_mask) ^ (goal & before_mask); + before_mask = (1 << (s_int << 3)) - 1; + v = (*p | before_mask) ^ (goal & before_mask); /* Compute the address of the last byte. */ - const char *const last_byte_ptr = (const char *)s + n - 1; + last_byte_ptr = (const char *)s + n - 1; /* Compute the address of the word containing the last byte. */ - const uint32_t *const last_word_ptr = - (const uint32_t *)((uintptr_t) last_byte_ptr & -4); - - uint32_t bits; - char *ret; - - if (__builtin_expect(n == 0, 0)) { - /* Don't dereference any memory if the array is empty. */ - return NULL; - } + last_word_ptr = (const uint32_t *)((uintptr_t) last_byte_ptr & -4); while ((bits = __insn_seqb(v, goal)) == 0) { if (__builtin_expect(p == last_word_ptr, 0)) { diff --git a/arch/tile/lib/spinlock_32.c b/arch/tile/lib/spinlock_32.c index 485e24d..5cd1c40 100644 --- a/arch/tile/lib/spinlock_32.c +++ b/arch/tile/lib/spinlock_32.c @@ -167,23 +167,30 @@ void arch_write_lock_slow(arch_rwlock_t *rwlock, u32 val) * when we compare them. */ u32 my_ticket_; + u32 iterations = 0; - /* Take out the next ticket; this will also stop would-be readers. */ - if (val & 1) - val = get_rwlock(rwlock); - rwlock->lock = __insn_addb(val, 1 << WR_NEXT_SHIFT); + /* + * Wait until there are no readers, then bump up the next + * field and capture the ticket value. + */ + for (;;) { + if (!(val & 1)) { + if ((val >> RD_COUNT_SHIFT) == 0) + break; + rwlock->lock = val; + } + delay_backoff(iterations++); + val = __insn_tns((int *)&rwlock->lock); + } - /* Extract my ticket value from the original word. */ + /* Take out the next ticket and extract my ticket value. */ + rwlock->lock = __insn_addb(val, 1 << WR_NEXT_SHIFT); my_ticket_ = val >> WR_NEXT_SHIFT; - /* - * Wait until the "current" field matches our ticket, and - * there are no remaining readers. - */ + /* Wait until the "current" field matches our ticket. */ for (;;) { u32 curr_ = val >> WR_CURR_SHIFT; - u32 readers = val >> RD_COUNT_SHIFT; - u32 delta = ((my_ticket_ - curr_) & WR_MASK) + !!readers; + u32 delta = ((my_ticket_ - curr_) & WR_MASK); if (likely(delta == 0)) break; |
