Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking/atomics update from Thomas Gleixner:
 "The locking, atomics and memory model brains delivered:

   - A larger update to the atomics code which reworks the ordering
     barriers, consolidates the atomic primitives, provides the new
     atomic64_fetch_add_unless() primitive and cleans up the include
     hell.

   - Simplify cmpxchg() instrumentation and add instrumentation for
     xchg() and cmpxchg_double().

   - Updates to the memory model and documentation"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
  locking/atomics: Rework ordering barriers
  locking/atomics: Instrument cmpxchg_double*()
  locking/atomics: Instrument xchg()
  locking/atomics: Simplify cmpxchg() instrumentation
  locking/atomics/x86: Reduce arch_cmpxchg64*() instrumentation
  tools/memory-model: Rename litmus tests to comply to norm7
  tools/memory-model/Documentation: Fix typo, smb->smp
  sched/Documentation: Update wake_up() & co. memory-barrier guarantees
  locking/spinlock, sched/core: Clarify requirements for smp_mb__after_spinlock()
  sched/core: Use smp_mb() in wake_woken_function()
  tools/memory-model: Add informal LKMM documentation to MAINTAINERS
  locking/atomics/Documentation: Describe atomic_set() as a write operation
  tools/memory-model: Make scripts executable
  tools/memory-model: Remove ACCESS_ONCE() from model
  tools/memory-model: Remove ACCESS_ONCE() from recipes
  locking/memory-barriers.txt/kokr: Update Korean translation to fix broken DMA vs. MMIO ordering example
  MAINTAINERS: Add Daniel Lustig as an LKMM reviewer
  tools/memory-model: Fix ISA2+pooncelock+pooncelock+pombonce name
  tools/memory-model: Add litmus test for full multicopy atomicity
  locking/refcount: Always allow checked forms
  ...
This commit is contained in:
Linus Torvalds
2018-08-13 12:23:39 -07:00
77 changed files with 991 additions and 1985 deletions

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@@ -80,6 +80,7 @@ static __always_inline void arch_atomic_sub(int i, atomic_t *v)
* true if the result is zero, or false for all
* other cases.
*/
#define arch_atomic_sub_and_test arch_atomic_sub_and_test
static __always_inline bool arch_atomic_sub_and_test(int i, atomic_t *v)
{
GEN_BINARY_RMWcc(LOCK_PREFIX "subl", v->counter, "er", i, "%0", e);
@@ -91,6 +92,7 @@ static __always_inline bool arch_atomic_sub_and_test(int i, atomic_t *v)
*
* Atomically increments @v by 1.
*/
#define arch_atomic_inc arch_atomic_inc
static __always_inline void arch_atomic_inc(atomic_t *v)
{
asm volatile(LOCK_PREFIX "incl %0"
@@ -103,6 +105,7 @@ static __always_inline void arch_atomic_inc(atomic_t *v)
*
* Atomically decrements @v by 1.
*/
#define arch_atomic_dec arch_atomic_dec
static __always_inline void arch_atomic_dec(atomic_t *v)
{
asm volatile(LOCK_PREFIX "decl %0"
@@ -117,6 +120,7 @@ static __always_inline void arch_atomic_dec(atomic_t *v)
* returns true if the result is 0, or false for all other
* cases.
*/
#define arch_atomic_dec_and_test arch_atomic_dec_and_test
static __always_inline bool arch_atomic_dec_and_test(atomic_t *v)
{
GEN_UNARY_RMWcc(LOCK_PREFIX "decl", v->counter, "%0", e);
@@ -130,6 +134,7 @@ static __always_inline bool arch_atomic_dec_and_test(atomic_t *v)
* and returns true if the result is zero, or false for all
* other cases.
*/
#define arch_atomic_inc_and_test arch_atomic_inc_and_test
static __always_inline bool arch_atomic_inc_and_test(atomic_t *v)
{
GEN_UNARY_RMWcc(LOCK_PREFIX "incl", v->counter, "%0", e);
@@ -144,6 +149,7 @@ static __always_inline bool arch_atomic_inc_and_test(atomic_t *v)
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
#define arch_atomic_add_negative arch_atomic_add_negative
static __always_inline bool arch_atomic_add_negative(int i, atomic_t *v)
{
GEN_BINARY_RMWcc(LOCK_PREFIX "addl", v->counter, "er", i, "%0", s);
@@ -173,9 +179,6 @@ static __always_inline int arch_atomic_sub_return(int i, atomic_t *v)
return arch_atomic_add_return(-i, v);
}
#define arch_atomic_inc_return(v) (arch_atomic_add_return(1, v))
#define arch_atomic_dec_return(v) (arch_atomic_sub_return(1, v))
static __always_inline int arch_atomic_fetch_add(int i, atomic_t *v)
{
return xadd(&v->counter, i);
@@ -199,7 +202,7 @@ static __always_inline bool arch_atomic_try_cmpxchg(atomic_t *v, int *old, int n
static inline int arch_atomic_xchg(atomic_t *v, int new)
{
return xchg(&v->counter, new);
return arch_xchg(&v->counter, new);
}
static inline void arch_atomic_and(int i, atomic_t *v)
@@ -253,27 +256,6 @@ static inline int arch_atomic_fetch_xor(int i, atomic_t *v)
return val;
}
/**
* __arch_atomic_add_unless - add unless the number is already a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
* Returns the old value of @v.
*/
static __always_inline int __arch_atomic_add_unless(atomic_t *v, int a, int u)
{
int c = arch_atomic_read(v);
do {
if (unlikely(c == u))
break;
} while (!arch_atomic_try_cmpxchg(v, &c, c + a));
return c;
}
#ifdef CONFIG_X86_32
# include <asm/atomic64_32.h>
#else

View File

@@ -158,6 +158,7 @@ static inline long long arch_atomic64_inc_return(atomic64_t *v)
"S" (v) : "memory", "ecx");
return a;
}
#define arch_atomic64_inc_return arch_atomic64_inc_return
static inline long long arch_atomic64_dec_return(atomic64_t *v)
{
@@ -166,6 +167,7 @@ static inline long long arch_atomic64_dec_return(atomic64_t *v)
"S" (v) : "memory", "ecx");
return a;
}
#define arch_atomic64_dec_return arch_atomic64_dec_return
/**
* arch_atomic64_add - add integer to atomic64 variable
@@ -197,26 +199,13 @@ static inline long long arch_atomic64_sub(long long i, atomic64_t *v)
return i;
}
/**
* arch_atomic64_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
*/
static inline int arch_atomic64_sub_and_test(long long i, atomic64_t *v)
{
return arch_atomic64_sub_return(i, v) == 0;
}
/**
* arch_atomic64_inc - increment atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1.
*/
#define arch_atomic64_inc arch_atomic64_inc
static inline void arch_atomic64_inc(atomic64_t *v)
{
__alternative_atomic64(inc, inc_return, /* no output */,
@@ -229,52 +218,13 @@ static inline void arch_atomic64_inc(atomic64_t *v)
*
* Atomically decrements @v by 1.
*/
#define arch_atomic64_dec arch_atomic64_dec
static inline void arch_atomic64_dec(atomic64_t *v)
{
__alternative_atomic64(dec, dec_return, /* no output */,
"S" (v) : "memory", "eax", "ecx", "edx");
}
/**
* arch_atomic64_dec_and_test - decrement and test
* @v: pointer to type atomic64_t
*
* Atomically decrements @v by 1 and
* returns true if the result is 0, or false for all other
* cases.
*/
static inline int arch_atomic64_dec_and_test(atomic64_t *v)
{
return arch_atomic64_dec_return(v) == 0;
}
/**
* atomic64_inc_and_test - increment and test
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
static inline int arch_atomic64_inc_and_test(atomic64_t *v)
{
return arch_atomic64_inc_return(v) == 0;
}
/**
* arch_atomic64_add_negative - add and test if negative
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
static inline int arch_atomic64_add_negative(long long i, atomic64_t *v)
{
return arch_atomic64_add_return(i, v) < 0;
}
/**
* arch_atomic64_add_unless - add unless the number is a given value
* @v: pointer of type atomic64_t
@@ -295,7 +245,7 @@ static inline int arch_atomic64_add_unless(atomic64_t *v, long long a,
return (int)a;
}
#define arch_atomic64_inc_not_zero arch_atomic64_inc_not_zero
static inline int arch_atomic64_inc_not_zero(atomic64_t *v)
{
int r;
@@ -304,6 +254,7 @@ static inline int arch_atomic64_inc_not_zero(atomic64_t *v)
return r;
}
#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
static inline long long arch_atomic64_dec_if_positive(atomic64_t *v)
{
long long r;

View File

@@ -71,6 +71,7 @@ static inline void arch_atomic64_sub(long i, atomic64_t *v)
* true if the result is zero, or false for all
* other cases.
*/
#define arch_atomic64_sub_and_test arch_atomic64_sub_and_test
static inline bool arch_atomic64_sub_and_test(long i, atomic64_t *v)
{
GEN_BINARY_RMWcc(LOCK_PREFIX "subq", v->counter, "er", i, "%0", e);
@@ -82,6 +83,7 @@ static inline bool arch_atomic64_sub_and_test(long i, atomic64_t *v)
*
* Atomically increments @v by 1.
*/
#define arch_atomic64_inc arch_atomic64_inc
static __always_inline void arch_atomic64_inc(atomic64_t *v)
{
asm volatile(LOCK_PREFIX "incq %0"
@@ -95,6 +97,7 @@ static __always_inline void arch_atomic64_inc(atomic64_t *v)
*
* Atomically decrements @v by 1.
*/
#define arch_atomic64_dec arch_atomic64_dec
static __always_inline void arch_atomic64_dec(atomic64_t *v)
{
asm volatile(LOCK_PREFIX "decq %0"
@@ -110,6 +113,7 @@ static __always_inline void arch_atomic64_dec(atomic64_t *v)
* returns true if the result is 0, or false for all other
* cases.
*/
#define arch_atomic64_dec_and_test arch_atomic64_dec_and_test
static inline bool arch_atomic64_dec_and_test(atomic64_t *v)
{
GEN_UNARY_RMWcc(LOCK_PREFIX "decq", v->counter, "%0", e);
@@ -123,6 +127,7 @@ static inline bool arch_atomic64_dec_and_test(atomic64_t *v)
* and returns true if the result is zero, or false for all
* other cases.
*/
#define arch_atomic64_inc_and_test arch_atomic64_inc_and_test
static inline bool arch_atomic64_inc_and_test(atomic64_t *v)
{
GEN_UNARY_RMWcc(LOCK_PREFIX "incq", v->counter, "%0", e);
@@ -137,6 +142,7 @@ static inline bool arch_atomic64_inc_and_test(atomic64_t *v)
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
#define arch_atomic64_add_negative arch_atomic64_add_negative
static inline bool arch_atomic64_add_negative(long i, atomic64_t *v)
{
GEN_BINARY_RMWcc(LOCK_PREFIX "addq", v->counter, "er", i, "%0", s);
@@ -169,9 +175,6 @@ static inline long arch_atomic64_fetch_sub(long i, atomic64_t *v)
return xadd(&v->counter, -i);
}
#define arch_atomic64_inc_return(v) (arch_atomic64_add_return(1, (v)))
#define arch_atomic64_dec_return(v) (arch_atomic64_sub_return(1, (v)))
static inline long arch_atomic64_cmpxchg(atomic64_t *v, long old, long new)
{
return arch_cmpxchg(&v->counter, old, new);
@@ -185,46 +188,7 @@ static __always_inline bool arch_atomic64_try_cmpxchg(atomic64_t *v, s64 *old, l
static inline long arch_atomic64_xchg(atomic64_t *v, long new)
{
return xchg(&v->counter, new);
}
/**
* arch_atomic64_add_unless - add unless the number is a given value
* @v: pointer of type atomic64_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as it was not @u.
* Returns the old value of @v.
*/
static inline bool arch_atomic64_add_unless(atomic64_t *v, long a, long u)
{
s64 c = arch_atomic64_read(v);
do {
if (unlikely(c == u))
return false;
} while (!arch_atomic64_try_cmpxchg(v, &c, c + a));
return true;
}
#define arch_atomic64_inc_not_zero(v) arch_atomic64_add_unless((v), 1, 0)
/*
* arch_atomic64_dec_if_positive - decrement by 1 if old value positive
* @v: pointer of type atomic_t
*
* The function returns the old value of *v minus 1, even if
* the atomic variable, v, was not decremented.
*/
static inline long arch_atomic64_dec_if_positive(atomic64_t *v)
{
s64 dec, c = arch_atomic64_read(v);
do {
dec = c - 1;
if (unlikely(dec < 0))
break;
} while (!arch_atomic64_try_cmpxchg(v, &c, dec));
return dec;
return arch_xchg(&v->counter, new);
}
static inline void arch_atomic64_and(long i, atomic64_t *v)

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@@ -75,7 +75,7 @@ extern void __add_wrong_size(void)
* use "asm volatile" and "memory" clobbers to prevent gcc from moving
* information around.
*/
#define xchg(ptr, v) __xchg_op((ptr), (v), xchg, "")
#define arch_xchg(ptr, v) __xchg_op((ptr), (v), xchg, "")
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,

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@@ -10,13 +10,13 @@ static inline void set_64bit(volatile u64 *ptr, u64 val)
#define arch_cmpxchg64(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg((ptr), (o), (n)); \
arch_cmpxchg((ptr), (o), (n)); \
})
#define arch_cmpxchg64_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg_local((ptr), (o), (n)); \
arch_cmpxchg_local((ptr), (o), (n)); \
})
#define system_has_cmpxchg_double() boot_cpu_has(X86_FEATURE_CX16)

View File

@@ -5,6 +5,7 @@
* PaX/grsecurity.
*/
#include <linux/refcount.h>
#include <asm/bug.h>
/*
* This is the first portion of the refcount error handling, which lives in