From a16ede35a2659170c855c5d267776666c0630f1f Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 16 Jan 2011 17:59:44 +0000 Subject: ARM: bitops: ensure set/clear/change bitops take a word-aligned pointer Add additional instructions to our assembly bitops functions to ensure that they only operate on word-aligned pointers. This will be necessary when we switch these operations to use the word-based exclusive operations. Signed-off-by: Russell King --- arch/arm/lib/bitops.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/arm/lib/bitops.h') diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h index d42252918bfb..bd00551fb797 100644 --- a/arch/arm/lib/bitops.h +++ b/arch/arm/lib/bitops.h @@ -1,6 +1,8 @@ #if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_CPU_32v6K) .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 @@ -14,6 +16,8 @@ .endm .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 @@ -32,6 +36,8 @@ .endm #else .macro bitop, instr + ands ip, r1, #3 + strneb r1, [ip] @ assert word-aligned and r2, r0, #7 mov r3, #1 mov r3, r3, lsl r2 @@ -52,6 +58,8 @@ * to avoid dirtying the data cache. */ .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 -- cgit v1.2.3 From 6323f0ccedf756dfe5f46549cec69a2d6d97937b Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 16 Jan 2011 18:02:17 +0000 Subject: 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 Tested-by: Sourav Poddar Tested-by: Will Deacon Tested-by: Tony Lindgren Signed-off-by: Russell King --- arch/arm/include/asm/bitops.h | 60 ++++++++++++++++--------------------------- arch/arm/kernel/armksyms.c | 18 +++++-------- arch/arm/lib/bitops.h | 38 ++++++++++++++------------- arch/arm/lib/changebit.S | 10 ++------ arch/arm/lib/clearbit.S | 11 ++------ arch/arm/lib/setbit.S | 11 ++------ arch/arm/lib/testchangebit.S | 9 +++---- arch/arm/lib/testclearbit.S | 9 +++---- arch/arm/lib/testsetbit.S | 9 +++---- 9 files changed, 63 insertions(+), 112 deletions(-) (limited to 'arch/arm/lib/bitops.h') diff --git a/arch/arm/include/asm/bitops.h b/arch/arm/include/asm/bitops.h index 7b1bb2bbaf88..af54ed102f5f 100644 --- a/arch/arm/include/asm/bitops.h +++ b/arch/arm/include/asm/bitops.h @@ -148,15 +148,19 @@ ____atomic_test_and_change_bit(unsigned int bit, volatile unsigned long *p) * Note that bit 0 is defined to be 32-bit word bit 0, not byte 0 bit 0. */ +/* + * Native endian assembly bitops. nr = 0 -> word 0 bit 0. + */ +extern void _set_bit(int nr, volatile unsigned long * p); +extern void _clear_bit(int nr, volatile unsigned long * p); +extern void _change_bit(int nr, volatile unsigned long * p); +extern int _test_and_set_bit(int nr, volatile unsigned long * p); +extern int _test_and_clear_bit(int nr, volatile unsigned long * p); +extern int _test_and_change_bit(int nr, volatile unsigned long * p); + /* * Little endian assembly bitops. nr = 0 -> byte 0 bit 0. */ -extern void _set_bit_le(int nr, volatile unsigned long * p); -extern void _clear_bit_le(int nr, volatile unsigned long * p); -extern void _change_bit_le(int nr, volatile unsigned long * p); -extern int _test_and_set_bit_le(int nr, volatile unsigned long * p); -extern int _test_and_clear_bit_le(int nr, volatile unsigned long * p); -extern int _test_and_change_bit_le(int nr, volatile unsigned long * p); extern int _find_first_zero_bit_le(const void * p, unsigned size); extern int _find_next_zero_bit_le(const void * p, int size, int offset); extern int _find_first_bit_le(const unsigned long *p, unsigned size); @@ -165,12 +169,6 @@ extern int _find_next_bit_le(const unsigned long *p, int size, int offset); /* * Big endian assembly bitops. nr = 0 -> byte 3 bit 0. */ -extern void _set_bit_be(int nr, volatile unsigned long * p); -extern void _clear_bit_be(int nr, volatile unsigned long * p); -extern void _change_bit_be(int nr, volatile unsigned long * p); -extern int _test_and_set_bit_be(int nr, volatile unsigned long * p); -extern int _test_and_clear_bit_be(int nr, volatile unsigned long * p); -extern int _test_and_change_bit_be(int nr, volatile unsigned long * p); extern int _find_first_zero_bit_be(const void * p, unsigned size); extern int _find_next_zero_bit_be(const void * p, int size, int offset); extern int _find_first_bit_be(const unsigned long *p, unsigned size); @@ -180,33 +178,26 @@ extern int _find_next_bit_be(const unsigned long *p, int size, int offset); /* * The __* form of bitops are non-atomic and may be reordered. */ -#define ATOMIC_BITOP_LE(name,nr,p) \ - (__builtin_constant_p(nr) ? \ - ____atomic_##name(nr, p) : \ - _##name##_le(nr,p)) - -#define ATOMIC_BITOP_BE(name,nr,p) \ - (__builtin_constant_p(nr) ? \ - ____atomic_##name(nr, p) : \ - _##name##_be(nr,p)) +#define ATOMIC_BITOP(name,nr,p) \ + (__builtin_constant_p(nr) ? ____atomic_##name(nr, p) : _##name(nr,p)) #else -#define ATOMIC_BITOP_LE(name,nr,p) _##name##_le(nr,p) -#define ATOMIC_BITOP_BE(name,nr,p) _##name##_be(nr,p) +#define ATOMIC_BITOP(name,nr,p) _##name(nr,p) #endif -#define NONATOMIC_BITOP(name,nr,p) \ - (____nonatomic_##name(nr, p)) +/* + * Native endian atomic definitions. + */ +#define set_bit(nr,p) ATOMIC_BITOP(set_bit,nr,p) +#define clear_bit(nr,p) ATOMIC_BITOP(clear_bit,nr,p) +#define change_bit(nr,p) ATOMIC_BITOP(change_bit,nr,p) +#define test_and_set_bit(nr,p) ATOMIC_BITOP(test_and_set_bit,nr,p) +#define test_and_clear_bit(nr,p) ATOMIC_BITOP(test_and_clear_bit,nr,p) +#define test_and_change_bit(nr,p) ATOMIC_BITOP(test_and_change_bit,nr,p) #ifndef __ARMEB__ /* * These are the little endian, atomic definitions. */ -#define set_bit(nr,p) ATOMIC_BITOP_LE(set_bit,nr,p) -#define clear_bit(nr,p) ATOMIC_BITOP_LE(clear_bit,nr,p) -#define change_bit(nr,p) ATOMIC_BITOP_LE(change_bit,nr,p) -#define test_and_set_bit(nr,p) ATOMIC_BITOP_LE(test_and_set_bit,nr,p) -#define test_and_clear_bit(nr,p) ATOMIC_BITOP_LE(test_and_clear_bit,nr,p) -#define test_and_change_bit(nr,p) ATOMIC_BITOP_LE(test_and_change_bit,nr,p) #define find_first_zero_bit(p,sz) _find_first_zero_bit_le(p,sz) #define find_next_zero_bit(p,sz,off) _find_next_zero_bit_le(p,sz,off) #define find_first_bit(p,sz) _find_first_bit_le(p,sz) @@ -215,16 +206,9 @@ extern int _find_next_bit_be(const unsigned long *p, int size, int offset); #define WORD_BITOFF_TO_LE(x) ((x)) #else - /* * These are the big endian, atomic definitions. */ -#define set_bit(nr,p) ATOMIC_BITOP_BE(set_bit,nr,p) -#define clear_bit(nr,p) ATOMIC_BITOP_BE(clear_bit,nr,p) -#define change_bit(nr,p) ATOMIC_BITOP_BE(change_bit,nr,p) -#define test_and_set_bit(nr,p) ATOMIC_BITOP_BE(test_and_set_bit,nr,p) -#define test_and_clear_bit(nr,p) ATOMIC_BITOP_BE(test_and_clear_bit,nr,p) -#define test_and_change_bit(nr,p) ATOMIC_BITOP_BE(test_and_change_bit,nr,p) #define find_first_zero_bit(p,sz) _find_first_zero_bit_be(p,sz) #define find_next_zero_bit(p,sz,off) _find_next_zero_bit_be(p,sz,off) #define find_first_bit(p,sz) _find_first_bit_be(p,sz) diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c index e5e1e5387678..d5d4185f0c24 100644 --- a/arch/arm/kernel/armksyms.c +++ b/arch/arm/kernel/armksyms.c @@ -140,24 +140,18 @@ EXPORT_SYMBOL(__aeabi_ulcmp); #endif /* bitops */ -EXPORT_SYMBOL(_set_bit_le); -EXPORT_SYMBOL(_test_and_set_bit_le); -EXPORT_SYMBOL(_clear_bit_le); -EXPORT_SYMBOL(_test_and_clear_bit_le); -EXPORT_SYMBOL(_change_bit_le); -EXPORT_SYMBOL(_test_and_change_bit_le); +EXPORT_SYMBOL(_set_bit); +EXPORT_SYMBOL(_test_and_set_bit); +EXPORT_SYMBOL(_clear_bit); +EXPORT_SYMBOL(_test_and_clear_bit); +EXPORT_SYMBOL(_change_bit); +EXPORT_SYMBOL(_test_and_change_bit); EXPORT_SYMBOL(_find_first_zero_bit_le); EXPORT_SYMBOL(_find_next_zero_bit_le); EXPORT_SYMBOL(_find_first_bit_le); EXPORT_SYMBOL(_find_next_bit_le); #ifdef __ARMEB__ -EXPORT_SYMBOL(_set_bit_be); -EXPORT_SYMBOL(_test_and_set_bit_be); -EXPORT_SYMBOL(_clear_bit_be); -EXPORT_SYMBOL(_test_and_clear_bit_be); -EXPORT_SYMBOL(_change_bit_be); -EXPORT_SYMBOL(_test_and_change_bit_be); EXPORT_SYMBOL(_find_first_zero_bit_be); EXPORT_SYMBOL(_find_next_zero_bit_be); EXPORT_SYMBOL(_find_first_bit_be); 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] diff --git a/arch/arm/lib/changebit.S b/arch/arm/lib/changebit.S index 80f3115cbee2..68ed5b62e839 100644 --- a/arch/arm/lib/changebit.S +++ b/arch/arm/lib/changebit.S @@ -12,12 +12,6 @@ #include "bitops.h" .text -/* Purpose : Function to change a bit - * Prototype: int change_bit(int bit, void *addr) - */ -ENTRY(_change_bit_be) - eor r0, r0, #0x18 @ big endian byte ordering -ENTRY(_change_bit_le) +ENTRY(_change_bit) bitop eor -ENDPROC(_change_bit_be) -ENDPROC(_change_bit_le) +ENDPROC(_change_bit) diff --git a/arch/arm/lib/clearbit.S b/arch/arm/lib/clearbit.S index 1a63e43a1df0..4c04c3b51eeb 100644 --- a/arch/arm/lib/clearbit.S +++ b/arch/arm/lib/clearbit.S @@ -12,13 +12,6 @@ #include "bitops.h" .text -/* - * Purpose : Function to clear a bit - * Prototype: int clear_bit(int bit, void *addr) - */ -ENTRY(_clear_bit_be) - eor r0, r0, #0x18 @ big endian byte ordering -ENTRY(_clear_bit_le) +ENTRY(_clear_bit) bitop bic -ENDPROC(_clear_bit_be) -ENDPROC(_clear_bit_le) +ENDPROC(_clear_bit) diff --git a/arch/arm/lib/setbit.S b/arch/arm/lib/setbit.S index 1dd7176c4b2b..bbee5c66a23e 100644 --- a/arch/arm/lib/setbit.S +++ b/arch/arm/lib/setbit.S @@ -12,13 +12,6 @@ #include "bitops.h" .text -/* - * Purpose : Function to set a bit - * Prototype: int set_bit(int bit, void *addr) - */ -ENTRY(_set_bit_be) - eor r0, r0, #0x18 @ big endian byte ordering -ENTRY(_set_bit_le) +ENTRY(_set_bit) bitop orr -ENDPROC(_set_bit_be) -ENDPROC(_set_bit_le) +ENDPROC(_set_bit) diff --git a/arch/arm/lib/testchangebit.S b/arch/arm/lib/testchangebit.S index 5c98dc567f0f..15a4d431f229 100644 --- a/arch/arm/lib/testchangebit.S +++ b/arch/arm/lib/testchangebit.S @@ -12,9 +12,6 @@ #include "bitops.h" .text -ENTRY(_test_and_change_bit_be) - eor r0, r0, #0x18 @ big endian byte ordering -ENTRY(_test_and_change_bit_le) - testop eor, strb -ENDPROC(_test_and_change_bit_be) -ENDPROC(_test_and_change_bit_le) +ENTRY(_test_and_change_bit) + testop eor, str +ENDPROC(_test_and_change_bit) diff --git a/arch/arm/lib/testclearbit.S b/arch/arm/lib/testclearbit.S index 543d7094d18e..521b66b5b95d 100644 --- a/arch/arm/lib/testclearbit.S +++ b/arch/arm/lib/testclearbit.S @@ -12,9 +12,6 @@ #include "bitops.h" .text -ENTRY(_test_and_clear_bit_be) - eor r0, r0, #0x18 @ big endian byte ordering -ENTRY(_test_and_clear_bit_le) - testop bicne, strneb -ENDPROC(_test_and_clear_bit_be) -ENDPROC(_test_and_clear_bit_le) +ENTRY(_test_and_clear_bit) + testop bicne, strne +ENDPROC(_test_and_clear_bit) diff --git a/arch/arm/lib/testsetbit.S b/arch/arm/lib/testsetbit.S index 0b3f390401ce..1c98cc2185bb 100644 --- a/arch/arm/lib/testsetbit.S +++ b/arch/arm/lib/testsetbit.S @@ -12,9 +12,6 @@ #include "bitops.h" .text -ENTRY(_test_and_set_bit_be) - eor r0, r0, #0x18 @ big endian byte ordering -ENTRY(_test_and_set_bit_le) - testop orreq, streqb -ENDPROC(_test_and_set_bit_be) -ENDPROC(_test_and_set_bit_le) +ENTRY(_test_and_set_bit) + testop orreq, streq +ENDPROC(_test_and_set_bit) -- cgit v1.2.3 From 3ba6e69ad887f8a814267ed36fd4bfbddf8855a9 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Tue, 8 Feb 2011 12:09:52 +0100 Subject: ARM: 6653/1: bitops: Use BX instead of MOV PC,LR The kernel doesn't officially need to interwork, but using BX wherever appropriate will help educate people into good assembler coding habits. BX is appropriate here because this code is predicated on __LINUX_ARM_ARCH__ >= 6 Signed-off-by: Dave Martin Acked-by: Nicolas Pitre Signed-off-by: Russell King --- arch/arm/lib/bitops.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm/lib/bitops.h') diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h index a9d9d152a751..10d868a5a481 100644 --- a/arch/arm/lib/bitops.h +++ b/arch/arm/lib/bitops.h @@ -12,7 +12,7 @@ strex r0, r2, [r1] cmp r0, #0 bne 1b - mov pc, lr + bx lr .endm .macro testop, instr, store @@ -33,7 +33,7 @@ smp_dmb cmp r0, #0 movne r0, #1 -2: mov pc, lr +2: bx lr .endm #else .macro bitop, instr -- cgit v1.2.3