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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-01-16 19:02:17 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2011-02-02 22:23:25 +0100 |
| commit | 6323f0ccedf756dfe5f46549cec69a2d6d97937b (patch) | |
| tree | 091e3408c12bbce33ef5d708b6131132b9660d4d /arch/arm/lib/bitops.h | |
| parent | ARM: bitops: ensure set/clear/change bitops take a word-aligned pointer (diff) | |
| download | linux-6323f0ccedf756dfe5f46549cec69a2d6d97937b.tar.xz linux-6323f0ccedf756dfe5f46549cec69a2d6d97937b.zip | |
ARM: bitops: switch set/clear/change bitops to use ldrex/strex
Switch the set/clear/change bitops to use the word-based exclusive
operations, which are only present in a wider range of ARM architectures
than the byte-based exclusive operations.
Tested record:
- Nicolas Pitre: ext3,rw,le
- Sourav Poddar: nfs,le
- Will Deacon: ext3,rw,le
- Tony Lindgren: ext3+nfs,le
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/lib/bitops.h')
| -rw-r--r-- | arch/arm/lib/bitops.h | 38 |
1 files changed, 20 insertions, 18 deletions
diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h index bd00551fb797..a9d9d152a751 100644 --- a/arch/arm/lib/bitops.h +++ b/arch/arm/lib/bitops.h @@ -1,15 +1,15 @@ - -#if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_CPU_32v6K) +#if __LINUX_ARM_ARCH__ >= 6 .macro bitop, instr ands ip, r1, #3 strneb r1, [ip] @ assert word-aligned mov r2, #1 - and r3, r0, #7 @ Get bit offset - add r1, r1, r0, lsr #3 @ Get byte offset + and r3, r0, #31 @ Get bit offset + mov r0, r0, lsr #5 + add r1, r1, r0, lsl #2 @ Get word offset mov r3, r2, lsl r3 -1: ldrexb r2, [r1] +1: ldrex r2, [r1] \instr r2, r2, r3 - strexb r0, r2, [r1] + strex r0, r2, [r1] cmp r0, #0 bne 1b mov pc, lr @@ -18,15 +18,16 @@ .macro testop, instr, store ands ip, r1, #3 strneb r1, [ip] @ assert word-aligned - and r3, r0, #7 @ Get bit offset mov r2, #1 - add r1, r1, r0, lsr #3 @ Get byte offset + and r3, r0, #31 @ Get bit offset + mov r0, r0, lsr #5 + add r1, r1, r0, lsl #2 @ Get word offset mov r3, r2, lsl r3 @ create mask smp_dmb -1: ldrexb r2, [r1] +1: ldrex r2, [r1] ands r0, r2, r3 @ save old value of bit - \instr r2, r2, r3 @ toggle bit - strexb ip, r2, [r1] + \instr r2, r2, r3 @ toggle bit + strex ip, r2, [r1] cmp ip, #0 bne 1b smp_dmb @@ -38,13 +39,14 @@ .macro bitop, instr ands ip, r1, #3 strneb r1, [ip] @ assert word-aligned - and r2, r0, #7 + and r2, r0, #31 + mov r0, r0, lsr #5 mov r3, #1 mov r3, r3, lsl r2 save_and_disable_irqs ip - ldrb r2, [r1, r0, lsr #3] + ldr r2, [r1, r0, lsl #2] \instr r2, r2, r3 - strb r2, [r1, r0, lsr #3] + str r2, [r1, r0, lsl #2] restore_irqs ip mov pc, lr .endm @@ -60,11 +62,11 @@ .macro testop, instr, store ands ip, r1, #3 strneb r1, [ip] @ assert word-aligned - add r1, r1, r0, lsr #3 - and r3, r0, #7 - mov r0, #1 + and r3, r0, #31 + mov r0, r0, lsr #5 save_and_disable_irqs ip - ldrb r2, [r1] + ldr r2, [r1, r0, lsl #2]! + mov r0, #1 tst r2, r0, lsl r3 \instr r2, r2, r0, lsl r3 \store r2, [r1] |