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>
diff --git a/arch/sparc/lib/Makefile b/arch/sparc/lib/Makefile
index c4b5e03..846d1c4 100644
--- a/arch/sparc/lib/Makefile
+++ b/arch/sparc/lib/Makefile
@@ -15,7 +15,7 @@
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 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 <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