From 9b3bb86acabe0c05923cea1ed3b0bee9439fef4b Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 17 Aug 2010 22:49:26 -0700 Subject: sparc64: Make rwsems 64-bit. Basically tip-off the powerpc code, use a 64-bit type and atomic64_t interfaces for the implementation. This gets us off of the by-hand asm code I wrote, which frankly I think probably ruins I-cache hit rates. The idea was the keep the call chains less deep, but anything taking the rw-semaphores probably is also calling other stuff and therefore already has allocated a stack-frame. So no real stack frame savings ever. Ben H. has posted patches to make powerpc use 64-bit too and with some abstractions we can probably use a shared header file somewhere. With suggestions from Sam Ravnborg. Signed-off-by: David S. Miller --- arch/sparc/lib/rwsem_64.S | 163 ---------------------------------------------- 1 file changed, 163 deletions(-) delete mode 100644 arch/sparc/lib/rwsem_64.S (limited to 'arch/sparc/lib/rwsem_64.S') diff --git a/arch/sparc/lib/rwsem_64.S b/arch/sparc/lib/rwsem_64.S deleted file mode 100644 index 91a7d29..0000000 --- a/arch/sparc/lib/rwsem_64.S +++ /dev/null @@ -1,163 +0,0 @@ -/* rwsem.S: RW semaphore assembler. - * - * Written by David S. Miller (davem@redhat.com), 2001. - * Derived from asm-i386/rwsem.h - */ - -#include - - .section .sched.text, "ax" - - .globl __down_read -__down_read: -1: lduw [%o0], %g1 - add %g1, 1, %g7 - cas [%o0], %g1, %g7 - cmp %g1, %g7 - bne,pn %icc, 1b - add %g7, 1, %g7 - cmp %g7, 0 - bl,pn %icc, 3f - nop -2: - retl - nop -3: - save %sp, -192, %sp - call rwsem_down_read_failed - mov %i0, %o0 - ret - restore - .size __down_read, .-__down_read - - .globl __down_read_trylock -__down_read_trylock: -1: lduw [%o0], %g1 - add %g1, 1, %g7 - cmp %g7, 0 - bl,pn %icc, 2f - mov 0, %o1 - cas [%o0], %g1, %g7 - cmp %g1, %g7 - bne,pn %icc, 1b - mov 1, %o1 -2: retl - mov %o1, %o0 - .size __down_read_trylock, .-__down_read_trylock - - .globl __down_write -__down_write: - sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1 - or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1 -1: - lduw [%o0], %g3 - add %g3, %g1, %g7 - cas [%o0], %g3, %g7 - cmp %g3, %g7 - bne,pn %icc, 1b - cmp %g7, 0 - bne,pn %icc, 3f - nop -2: retl - nop -3: - save %sp, -192, %sp - call rwsem_down_write_failed - mov %i0, %o0 - ret - restore - .size __down_write, .-__down_write - - .globl __down_write_trylock -__down_write_trylock: - sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1 - or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1 -1: - lduw [%o0], %g3 - cmp %g3, 0 - bne,pn %icc, 2f - mov 0, %o1 - add %g3, %g1, %g7 - cas [%o0], %g3, %g7 - cmp %g3, %g7 - bne,pn %icc, 1b - mov 1, %o1 -2: retl - mov %o1, %o0 - .size __down_write_trylock, .-__down_write_trylock - - .globl __up_read -__up_read: -1: - lduw [%o0], %g1 - sub %g1, 1, %g7 - cas [%o0], %g1, %g7 - cmp %g1, %g7 - bne,pn %icc, 1b - cmp %g7, 0 - bl,pn %icc, 3f - nop -2: retl - nop -3: sethi %hi(RWSEM_ACTIVE_MASK), %g1 - sub %g7, 1, %g7 - or %g1, %lo(RWSEM_ACTIVE_MASK), %g1 - andcc %g7, %g1, %g0 - bne,pn %icc, 2b - nop - save %sp, -192, %sp - call rwsem_wake - mov %i0, %o0 - ret - restore - .size __up_read, .-__up_read - - .globl __up_write -__up_write: - sethi %hi(RWSEM_ACTIVE_WRITE_BIAS), %g1 - or %g1, %lo(RWSEM_ACTIVE_WRITE_BIAS), %g1 -1: - lduw [%o0], %g3 - sub %g3, %g1, %g7 - cas [%o0], %g3, %g7 - cmp %g3, %g7 - bne,pn %icc, 1b - sub %g7, %g1, %g7 - cmp %g7, 0 - bl,pn %icc, 3f - nop -2: - retl - nop -3: - save %sp, -192, %sp - call rwsem_wake - mov %i0, %o0 - ret - restore - .size __up_write, .-__up_write - - .globl __downgrade_write -__downgrade_write: - sethi %hi(RWSEM_WAITING_BIAS), %g1 - or %g1, %lo(RWSEM_WAITING_BIAS), %g1 -1: - lduw [%o0], %g3 - sub %g3, %g1, %g7 - cas [%o0], %g3, %g7 - cmp %g3, %g7 - bne,pn %icc, 1b - sub %g7, %g1, %g7 - cmp %g7, 0 - bl,pn %icc, 3f - nop -2: - retl - nop -3: - save %sp, -192, %sp - call rwsem_downgrade_wake - mov %i0, %o0 - ret - restore - .size __downgrade_write, .-__downgrade_write -- cgit v1.1