This is backport of the upstream patch d6ffe6067a54972564552ea45d320fb98db1ac5e
for the stable branch 4.9
provide arch_test_bit_acquire for architectures that define test_bit
Some architectures define their own arch_test_bit and they also need
arch_test_bit_acquire, otherwise they won't compile. We also clean up
the code by using the generic test_bit if that is equivalent to the
arch-specific version.
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 8238b4579866 ("wait_on_bit: add an acquire memory barrier")
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
---
arch/alpha/include/asm/bitops.h | 7 +++++++
arch/hexagon/include/asm/bitops.h | 15 +++++++++++++++
arch/ia64/include/asm/bitops.h | 7 +++++++
arch/m68k/include/asm/bitops.h | 6 ++++++
arch/s390/include/asm/bitops.h | 7 +++++++
arch/sh/include/asm/bitops-op32.h | 7 +++++++
6 files changed, 49 insertions(+)
Index: linux-stable/arch/alpha/include/asm/bitops.h
===================================================================
--- linux-stable.orig/arch/alpha/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
+++ linux-stable/arch/alpha/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
@@ -288,6 +288,13 @@ test_bit(int nr, const volatile void * a
return (1UL & (((const int *) addr)[nr >> 5] >> (nr & 31))) != 0UL;
}
+static __always_inline bool
+test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
+{
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ return 1UL & (smp_load_acquire(p) >> (nr & (BITS_PER_LONG-1)));
+}
+
/*
* ffz = Find First Zero in word. Undefined if no zero exists,
* so code should check against ~0UL first..
Index: linux-stable/arch/hexagon/include/asm/bitops.h
===================================================================
--- linux-stable.orig/arch/hexagon/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
+++ linux-stable/arch/hexagon/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
@@ -186,7 +186,22 @@ static inline int __test_bit(int nr, con
return retval;
}
+static inline int __test_bit_acquire(int nr, const volatile unsigned long *addr)
+{
+ int retval;
+
+ asm volatile(
+ "{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n"
+ : "=&r" (retval)
+ : "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG)
+ : "p0", "memory"
+ );
+
+ return retval;
+}
+
#define test_bit(nr, addr) __test_bit(nr, addr)
+#define test_bit_acquire(nr, addr) __test_bit_acquire(nr, addr)
/*
* ffz - find first zero in word.
Index: linux-stable/arch/ia64/include/asm/bitops.h
===================================================================
--- linux-stable.orig/arch/ia64/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
+++ linux-stable/arch/ia64/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
@@ -336,6 +336,13 @@ test_bit (int nr, const volatile void *a
return 1 & (((const volatile __u32 *) addr)[nr >> 5] >> (nr & 31));
}
+static __always_inline bool
+test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
+{
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ return 1UL & (smp_load_acquire(p) >> (nr & (BITS_PER_LONG-1)));
+}
+
/**
* ffz - find the first zero bit in a long word
* @x: The long word to find the bit in
Index: linux-stable/arch/m68k/include/asm/bitops.h
===================================================================
--- linux-stable.orig/arch/m68k/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
+++ linux-stable/arch/m68k/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
@@ -153,6 +153,12 @@ static inline int test_bit(int nr, const
return (vaddr[nr >> 5] & (1UL << (nr & 31))) != 0;
}
+static __always_inline bool
+test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
+{
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ return 1UL & (smp_load_acquire(p) >> (nr & (BITS_PER_LONG-1)));
+}
static inline int bset_reg_test_and_set_bit(int nr,
volatile unsigned long *vaddr)
Index: linux-stable/arch/s390/include/asm/bitops.h
===================================================================
--- linux-stable.orig/arch/s390/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
+++ linux-stable/arch/s390/include/asm/bitops.h 2022-09-30 16:03:22.000000000 +0200
@@ -270,6 +270,13 @@ static inline int test_bit(unsigned long
return (*addr >> (nr & 7)) & 1;
}
+static __always_inline bool
+test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
+{
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ return 1UL & (smp_load_acquire(p) >> (nr & (BITS_PER_LONG-1)));
+}
+
static inline int test_and_set_bit_lock(unsigned long nr,
volatile unsigned long *ptr)
{
Index: linux-stable/arch/sh/include/asm/bitops-op32.h
===================================================================
--- linux-stable.orig/arch/sh/include/asm/bitops-op32.h 2022-09-30 16:03:22.000000000 +0200
+++ linux-stable/arch/sh/include/asm/bitops-op32.h 2022-09-30 16:03:22.000000000 +0200
@@ -139,4 +139,11 @@ static inline int test_bit(int nr, const
return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1)));
}
+static __always_inline bool
+test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
+{
+ unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr);
+ return 1UL & (smp_load_acquire(p) >> (nr & (BITS_PER_LONG-1)));
+}
+
#endif /* __ASM_SH_BITOPS_OP32_H */
