diff options
author | David S. Miller <davem@davemloft.net> | 2010-08-18 09:49:26 +0400 |
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committer | David S. Miller <davem@davemloft.net> | 2010-08-18 09:49:26 +0400 |
commit | 9b3bb86acabe0c05923cea1ed3b0bee9439fef4b (patch) | |
tree | 44095535e5f2634c319122b718c8998ee3b52511 /arch/sparc/lib | |
parent | b10f997bb0f4e5b34d447f498fb85834a40d3acb (diff) | |
download | linux-9b3bb86acabe0c05923cea1ed3b0bee9439fef4b.tar.xz |
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 <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/lib')
-rw-r--r-- | arch/sparc/lib/Makefile | 2 | ||||
-rw-r--r-- | arch/sparc/lib/rwsem_64.S | 163 |
2 files changed, 1 insertions, 164 deletions
diff --git a/arch/sparc/lib/Makefile b/arch/sparc/lib/Makefile index c4b5e03af115..846d1c4374ea 100644 --- a/arch/sparc/lib/Makefile +++ b/arch/sparc/lib/Makefile @@ -15,7 +15,7 @@ lib-$(CONFIG_SPARC32) += divdi3.o udivdi3.o lib-$(CONFIG_SPARC32) += copy_user.o locks.o lib-y += atomic_$(BITS).o lib-$(CONFIG_SPARC32) += lshrdi3.o ashldi3.o -lib-y += rwsem_$(BITS).o +lib-$(CONFIG_SPARC32) += rwsem_32.o lib-$(CONFIG_SPARC32) += muldi3.o bitext.o cmpdi2.o lib-$(CONFIG_SPARC64) += copy_page.o clear_page.o bzero.o diff --git a/arch/sparc/lib/rwsem_64.S b/arch/sparc/lib/rwsem_64.S deleted file mode 100644 index 91a7d29a79d5..000000000000 --- 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 <asm/rwsem-const.h> - - .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 |