Align the locks for the Light weight syscall (LWS) which is used for atomic userspace operations (e.g. gcc atomic builtins) on L1 cache boundaries. This should speed up LWS calls on PA20 systems. Reported-by: John David Anglin <dave.anglin@xxxxxxxx> Signed-off-by: Helge Deller <deller@xxxxxx> diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index 7ef22e3..80c2306 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -561,9 +561,9 @@ lws_compare_and_swap: extru %r26, 27, 4, %r20 /* Find lock to use, the hash is either one of 0 to - 15, multiplied by 16 (keep it 16-byte aligned) + 15, multiplied by L1_CACHE_BYTES (keep it L1 cache aligned) and add to the lock table offset. */ - shlw %r20, 4, %r20 + shlw %r20, L1_CACHE_SHIFT, %r20 add %r20, %r28, %r20 # if ENABLE_LWS_DEBUG @@ -751,9 +751,9 @@ cas2_lock_start: extru %r26, 27, 4, %r20 /* Find lock to use, the hash is either one of 0 to - 15, multiplied by 16 (keep it 16-byte aligned) + 15, multiplied by L1_CACHE_BYTES (keep it L1 cache aligned) and add to the lock table offset. */ - shlw %r20, 4, %r20 + shlw %r20, L1_CACHE_SHIFT, %r20 add %r20, %r28, %r20 rsm PSW_SM_I, %r0 /* Disable interrupts */ @@ -931,11 +931,9 @@ END(sys_call_table64) ENTRY(lws_lock_start) /* lws locks */ .rept 16 - /* Keep locks aligned at 16-bytes */ + /* Keep locks aligned to L1_CACHE_BYTES */ .word 1 - .word 0 - .word 0 - .word 0 + .align L1_CACHE_BYTES .endr END(lws_lock_start) .previous -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
