aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-07-10 14:25:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-07-10 14:25:03 -0700
commit85be928c4101670f99cdd7c927798aa4dcbb3168 (patch)
tree91befa19ca6da9edf74040bd1fd0cf68ab0cea4c /arch/x86
parentsched: optimize cond_resched() (diff)
parentperf report: Add "Fractal" mode output - support callchains with relative overhead rate (diff)
downloadlinux-dev-85be928c4101670f99cdd7c927798aa4dcbb3168.tar.xz
linux-dev-85be928c4101670f99cdd7c927798aa4dcbb3168.zip
Merge branch 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (50 commits) perf report: Add "Fractal" mode output - support callchains with relative overhead rate perf_counter tools: callchains: Manage the cumul hits on the fly perf report: Change default callchain parameters perf report: Use a modifiable string for default callchain options perf report: Warn on callchain output request from non-callchain file x86: atomic64: Inline atomic64_read() again x86: atomic64: Clean up atomic64_sub_and_test() and atomic64_add_negative() x86: atomic64: Improve atomic64_xchg() x86: atomic64: Export APIs to modules x86: atomic64: Improve atomic64_read() x86: atomic64: Code atomic(64)_read and atomic(64)_set in C not CPP x86: atomic64: Fix unclean type use in atomic64_xchg() x86: atomic64: Make atomic_read() type-safe x86: atomic64: Reduce size of functions x86: atomic64: Improve atomic64_add_return() x86: atomic64: Improve cmpxchg8b() x86: atomic64: Improve atomic64_read() x86: atomic64: Move the 32-bit atomic64_t implementation to a .c file x86: atomic64: The atomic64_t data type should be 8 bytes aligned on 32-bit too perf report: Annotate variable initialization ...
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/atomic_32.h185
-rw-r--r--arch/x86/include/asm/atomic_64.h42
-rw-r--r--arch/x86/include/asm/stacktrace.h2
-rw-r--r--arch/x86/kernel/cpu/perf_counter.c8
-rw-r--r--arch/x86/kernel/dumpstack_32.c6
-rw-r--r--arch/x86/kernel/dumpstack_64.c22
-rw-r--r--arch/x86/lib/Makefile1
-rw-r--r--arch/x86/lib/atomic64_32.c230
8 files changed, 352 insertions, 144 deletions
diff --git a/arch/x86/include/asm/atomic_32.h b/arch/x86/include/asm/atomic_32.h
index 2503d4e64c2a..dc5a667ff791 100644
--- a/arch/x86/include/asm/atomic_32.h
+++ b/arch/x86/include/asm/atomic_32.h
@@ -19,7 +19,10 @@
*
* Atomically reads the value of @v.
*/
-#define atomic_read(v) ((v)->counter)
+static inline int atomic_read(const atomic_t *v)
+{
+ return v->counter;
+}
/**
* atomic_set - set atomic variable
@@ -28,7 +31,10 @@
*
* Atomically sets the value of @v to @i.
*/
-#define atomic_set(v, i) (((v)->counter) = (i))
+static inline void atomic_set(atomic_t *v, int i)
+{
+ v->counter = i;
+}
/**
* atomic_add - add integer to atomic variable
@@ -200,8 +206,15 @@ static inline int atomic_sub_return(int i, atomic_t *v)
return atomic_add_return(-i, v);
}
-#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
-#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ return cmpxchg(&v->counter, old, new);
+}
+
+static inline int atomic_xchg(atomic_t *v, int new)
+{
+ return xchg(&v->counter, new);
+}
/**
* atomic_add_unless - add unless the number is already a given value
@@ -250,45 +263,12 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
/* An 64bit atomic type */
typedef struct {
- unsigned long long counter;
+ u64 __aligned(8) counter;
} atomic64_t;
#define ATOMIC64_INIT(val) { (val) }
-/**
- * atomic64_read - read atomic64 variable
- * @ptr: pointer of type atomic64_t
- *
- * Atomically reads the value of @v.
- * Doesn't imply a read memory barrier.
- */
-#define __atomic64_read(ptr) ((ptr)->counter)
-
-static inline unsigned long long
-cmpxchg8b(unsigned long long *ptr, unsigned long long old, unsigned long long new)
-{
- asm volatile(
-
- LOCK_PREFIX "cmpxchg8b (%[ptr])\n"
-
- : "=A" (old)
-
- : [ptr] "D" (ptr),
- "A" (old),
- "b" (ll_low(new)),
- "c" (ll_high(new))
-
- : "memory");
-
- return old;
-}
-
-static inline unsigned long long
-atomic64_cmpxchg(atomic64_t *ptr, unsigned long long old_val,
- unsigned long long new_val)
-{
- return cmpxchg8b(&ptr->counter, old_val, new_val);
-}
+extern u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val);
/**
* atomic64_xchg - xchg atomic64 variable
@@ -298,18 +278,7 @@ atomic64_cmpxchg(atomic64_t *ptr, unsigned long long old_val,
* Atomically xchgs the value of @ptr to @new_val and returns
* the old value.
*/
-
-static inline unsigned long long
-atomic64_xchg(atomic64_t *ptr, unsigned long long new_val)
-{
- unsigned long long old_val;
-
- do {
- old_val = atomic_read(ptr);
- } while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val);
-
- return old_val;
-}
+extern u64 atomic64_xchg(atomic64_t *ptr, u64 new_val);
/**
* atomic64_set - set atomic64 variable
@@ -318,10 +287,7 @@ atomic64_xchg(atomic64_t *ptr, unsigned long long new_val)
*
* Atomically sets the value of @ptr to @new_val.
*/
-static inline void atomic64_set(atomic64_t *ptr, unsigned long long new_val)
-{
- atomic64_xchg(ptr, new_val);
-}
+extern void atomic64_set(atomic64_t *ptr, u64 new_val);
/**
* atomic64_read - read atomic64 variable
@@ -329,17 +295,30 @@ static inline void atomic64_set(atomic64_t *ptr, unsigned long long new_val)
*
* Atomically reads the value of @ptr and returns it.
*/
-static inline unsigned long long atomic64_read(atomic64_t *ptr)
+static inline u64 atomic64_read(atomic64_t *ptr)
{
- unsigned long long curr_val;
-
- do {
- curr_val = __atomic64_read(ptr);
- } while (atomic64_cmpxchg(ptr, curr_val, curr_val) != curr_val);
-
- return curr_val;
+ u64 res;
+
+ /*
+ * Note, we inline this atomic64_t primitive because
+ * it only clobbers EAX/EDX and leaves the others
+ * untouched. We also (somewhat subtly) rely on the
+ * fact that cmpxchg8b returns the current 64-bit value
+ * of the memory location we are touching:
+ */
+ asm volatile(
+ "mov %%ebx, %%eax\n\t"
+ "mov %%ecx, %%edx\n\t"
+ LOCK_PREFIX "cmpxchg8b %1\n"
+ : "=&A" (res)
+ : "m" (*ptr)
+ );
+
+ return res;
}
+extern u64 atomic64_read(atomic64_t *ptr);
+
/**
* atomic64_add_return - add and return
* @delta: integer value to add
@@ -347,34 +326,14 @@ static inline unsigned long long atomic64_read(atomic64_t *ptr)
*
* Atomically adds @delta to @ptr and returns @delta + *@ptr
*/
-static inline unsigned long long
-atomic64_add_return(unsigned long long delta, atomic64_t *ptr)
-{
- unsigned long long old_val, new_val;
-
- do {
- old_val = atomic_read(ptr);
- new_val = old_val + delta;
-
- } while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val);
-
- return new_val;
-}
-
-static inline long atomic64_sub_return(unsigned long long delta, atomic64_t *ptr)
-{
- return atomic64_add_return(-delta, ptr);
-}
+extern u64 atomic64_add_return(u64 delta, atomic64_t *ptr);
-static inline long atomic64_inc_return(atomic64_t *ptr)
-{
- return atomic64_add_return(1, ptr);
-}
-
-static inline long atomic64_dec_return(atomic64_t *ptr)
-{
- return atomic64_sub_return(1, ptr);
-}
+/*
+ * Other variants with different arithmetic operators:
+ */
+extern u64 atomic64_sub_return(u64 delta, atomic64_t *ptr);
+extern u64 atomic64_inc_return(atomic64_t *ptr);
+extern u64 atomic64_dec_return(atomic64_t *ptr);
/**
* atomic64_add - add integer to atomic64 variable
@@ -383,10 +342,7 @@ static inline long atomic64_dec_return(atomic64_t *ptr)
*
* Atomically adds @delta to @ptr.
*/
-static inline void atomic64_add(unsigned long long delta, atomic64_t *ptr)
-{
- atomic64_add_return(delta, ptr);
-}
+extern void atomic64_add(u64 delta, atomic64_t *ptr);
/**
* atomic64_sub - subtract the atomic64 variable
@@ -395,10 +351,7 @@ static inline void atomic64_add(unsigned long long delta, atomic64_t *ptr)
*
* Atomically subtracts @delta from @ptr.
*/
-static inline void atomic64_sub(unsigned long long delta, atomic64_t *ptr)
-{
- atomic64_add(-delta, ptr);
-}
+extern void atomic64_sub(u64 delta, atomic64_t *ptr);
/**
* atomic64_sub_and_test - subtract value from variable and test result
@@ -409,13 +362,7 @@ static inline void atomic64_sub(unsigned long long delta, atomic64_t *ptr)
* true if the result is zero, or false for all
* other cases.
*/
-static inline int
-atomic64_sub_and_test(unsigned long long delta, atomic64_t *ptr)
-{
- unsigned long long old_val = atomic64_sub_return(delta, ptr);
-
- return old_val == 0;
-}
+extern int atomic64_sub_and_test(u64 delta, atomic64_t *ptr);
/**
* atomic64_inc - increment atomic64 variable
@@ -423,10 +370,7 @@ atomic64_sub_and_test(unsigned long long delta, atomic64_t *ptr)
*
* Atomically increments @ptr by 1.
*/
-static inline void atomic64_inc(atomic64_t *ptr)
-{
- atomic64_add(1, ptr);
-}
+extern void atomic64_inc(atomic64_t *ptr);
/**
* atomic64_dec - decrement atomic64 variable
@@ -434,10 +378,7 @@ static inline void atomic64_inc(atomic64_t *ptr)
*
* Atomically decrements @ptr by 1.
*/
-static inline void atomic64_dec(atomic64_t *ptr)
-{
- atomic64_sub(1, ptr);
-}
+extern void atomic64_dec(atomic64_t *ptr);
/**
* atomic64_dec_and_test - decrement and test
@@ -447,10 +388,7 @@ static inline void atomic64_dec(atomic64_t *ptr)
* returns true if the result is 0, or false for all other
* cases.
*/
-static inline int atomic64_dec_and_test(atomic64_t *ptr)
-{
- return atomic64_sub_and_test(1, ptr);
-}
+extern int atomic64_dec_and_test(atomic64_t *ptr);
/**
* atomic64_inc_and_test - increment and test
@@ -460,10 +398,7 @@ static inline int atomic64_dec_and_test(atomic64_t *ptr)
* and returns true if the result is zero, or false for all
* other cases.
*/
-static inline int atomic64_inc_and_test(atomic64_t *ptr)
-{
- return atomic64_sub_and_test(-1, ptr);
-}
+extern int atomic64_inc_and_test(atomic64_t *ptr);
/**
* atomic64_add_negative - add and test if negative
@@ -474,13 +409,7 @@ static inline int atomic64_inc_and_test(atomic64_t *ptr)
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
-static inline int
-atomic64_add_negative(unsigned long long delta, atomic64_t *ptr)
-{
- long long old_val = atomic64_add_return(delta, ptr);
-
- return old_val < 0;
-}
+extern int atomic64_add_negative(u64 delta, atomic64_t *ptr);
#include <asm-generic/atomic-long.h>
#endif /* _ASM_X86_ATOMIC_32_H */
diff --git a/arch/x86/include/asm/atomic_64.h b/arch/x86/include/asm/atomic_64.h
index 0d6360220007..d605dc268e79 100644
--- a/arch/x86/include/asm/atomic_64.h
+++ b/arch/x86/include/asm/atomic_64.h
@@ -18,7 +18,10 @@
*
* Atomically reads the value of @v.
*/
-#define atomic_read(v) ((v)->counter)
+static inline int atomic_read(const atomic_t *v)
+{
+ return v->counter;
+}
/**
* atomic_set - set atomic variable
@@ -27,7 +30,10 @@
*
* Atomically sets the value of @v to @i.
*/
-#define atomic_set(v, i) (((v)->counter) = (i))
+static inline void atomic_set(atomic_t *v, int i)
+{
+ v->counter = i;
+}
/**
* atomic_add - add integer to atomic variable
@@ -192,7 +198,10 @@ static inline int atomic_sub_return(int i, atomic_t *v)
* Atomically reads the value of @v.
* Doesn't imply a read memory barrier.
*/
-#define atomic64_read(v) ((v)->counter)
+static inline long atomic64_read(const atomic64_t *v)
+{
+ return v->counter;
+}
/**
* atomic64_set - set atomic64 variable
@@ -201,7 +210,10 @@ static inline int atomic_sub_return(int i, atomic_t *v)
*
* Atomically sets the value of @v to @i.
*/
-#define atomic64_set(v, i) (((v)->counter) = (i))
+static inline void atomic64_set(atomic64_t *v, long i)
+{
+ v->counter = i;
+}
/**
* atomic64_add - add integer to atomic64 variable
@@ -355,11 +367,25 @@ static inline long atomic64_sub_return(long i, atomic64_t *v)
#define atomic64_inc_return(v) (atomic64_add_return(1, (v)))
#define atomic64_dec_return(v) (atomic64_sub_return(1, (v)))
-#define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
-#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
+static inline long atomic64_cmpxchg(atomic64_t *v, long old, long new)
+{
+ return cmpxchg(&v->counter, old, new);
+}
+
+static inline long atomic64_xchg(atomic64_t *v, long new)
+{
+ return xchg(&v->counter, new);
+}
-#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
-#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
+static inline long atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ return cmpxchg(&v->counter, old, new);
+}
+
+static inline long atomic_xchg(atomic_t *v, int new)
+{
+ return xchg(&v->counter, new);
+}
/**
* atomic_add_unless - add unless the number is a given value
diff --git a/arch/x86/include/asm/stacktrace.h b/arch/x86/include/asm/stacktrace.h
index f517944b2b17..cf86a5e73815 100644
--- a/arch/x86/include/asm/stacktrace.h
+++ b/arch/x86/include/asm/stacktrace.h
@@ -3,6 +3,8 @@
extern int kstack_depth_to_print;
+int x86_is_stack_id(int id, char *name);
+
/* Generic stack tracer with callbacks */
struct stacktrace_ops {
diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
index d4cf4ce19aac..36c3dc7b8991 100644
--- a/arch/x86/kernel/cpu/perf_counter.c
+++ b/arch/x86/kernel/cpu/perf_counter.c
@@ -1561,6 +1561,7 @@ void callchain_store(struct perf_callchain_entry *entry, u64 ip)
static DEFINE_PER_CPU(struct perf_callchain_entry, irq_entry);
static DEFINE_PER_CPU(struct perf_callchain_entry, nmi_entry);
+static DEFINE_PER_CPU(int, in_nmi_frame);
static void
@@ -1576,7 +1577,9 @@ static void backtrace_warning(void *data, char *msg)
static int backtrace_stack(void *data, char *name)
{
- /* Process all stacks: */
+ per_cpu(in_nmi_frame, smp_processor_id()) =
+ x86_is_stack_id(NMI_STACK, name);
+
return 0;
}
@@ -1584,6 +1587,9 @@ static void backtrace_address(void *data, unsigned long addr, int reliable)
{
struct perf_callchain_entry *entry = data;
+ if (per_cpu(in_nmi_frame, smp_processor_id()))
+ return;
+
if (reliable)
callchain_store(entry, addr);
}
diff --git a/arch/x86/kernel/dumpstack_32.c b/arch/x86/kernel/dumpstack_32.c
index d593cd1f58dc..bca5fba91c9e 100644
--- a/arch/x86/kernel/dumpstack_32.c
+++ b/arch/x86/kernel/dumpstack_32.c
@@ -19,6 +19,12 @@
#include "dumpstack.h"
+/* Just a stub for now */
+int x86_is_stack_id(int id, char *name)
+{
+ return 0;
+}
+
void dump_trace(struct task_struct *task, struct pt_regs *regs,
unsigned long *stack, unsigned long bp,
const struct stacktrace_ops *ops, void *data)
diff --git a/arch/x86/kernel/dumpstack_64.c b/arch/x86/kernel/dumpstack_64.c
index d35db5993fd6..54b0a3276766 100644
--- a/arch/x86/kernel/dumpstack_64.c
+++ b/arch/x86/kernel/dumpstack_64.c
@@ -19,10 +19,8 @@
#include "dumpstack.h"
-static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
- unsigned *usedp, char **idp)
-{
- static char ids[][8] = {
+
+static char x86_stack_ids[][8] = {
[DEBUG_STACK - 1] = "#DB",
[NMI_STACK - 1] = "NMI",
[DOUBLEFAULT_STACK - 1] = "#DF",
@@ -33,6 +31,15 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
N_EXCEPTION_STACKS + DEBUG_STKSZ / EXCEPTION_STKSZ - 2] = "#DB[?]"
#endif
};
+
+int x86_is_stack_id(int id, char *name)
+{
+ return x86_stack_ids[id - 1] == name;
+}
+
+static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
+ unsigned *usedp, char **idp)
+{
unsigned k;
/*
@@ -61,7 +68,7 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
if (*usedp & (1U << k))
break;
*usedp |= 1U << k;
- *idp = ids[k];
+ *idp = x86_stack_ids[k];
return (unsigned long *)end;
}
/*
@@ -81,12 +88,13 @@ static unsigned long *in_exception_stack(unsigned cpu, unsigned long stack,
do {
++j;
end -= EXCEPTION_STKSZ;
- ids[j][4] = '1' + (j - N_EXCEPTION_STACKS);
+ x86_stack_ids[j][4] = '1' +
+ (j - N_EXCEPTION_STACKS);
} while (stack < end - EXCEPTION_STKSZ);
if (*usedp & (1U << j))
break;
*usedp |= 1U << j;
- *idp = ids[j];
+ *idp = x86_stack_ids[j];
return (unsigned long *)end;
}
#endif
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index f9d35632666b..07c31899c9c2 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -10,6 +10,7 @@ lib-y += usercopy_$(BITS).o getuser.o putuser.o
lib-y += memcpy_$(BITS).o
ifeq ($(CONFIG_X86_32),y)
+ obj-y += atomic64_32.o
lib-y += checksum_32.o
lib-y += strstr_32.o
lib-y += semaphore_32.o string_32.o
diff --git a/arch/x86/lib/atomic64_32.c b/arch/x86/lib/atomic64_32.c
new file mode 100644
index 000000000000..824fa0be55a3
--- /dev/null
+++ b/arch/x86/lib/atomic64_32.c
@@ -0,0 +1,230 @@
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <asm/processor.h>
+#include <asm/cmpxchg.h>
+#include <asm/atomic.h>
+
+static noinline u64 cmpxchg8b(u64 *ptr, u64 old, u64 new)
+{
+ u32 low = new;
+ u32 high = new >> 32;
+
+ asm volatile(
+ LOCK_PREFIX "cmpxchg8b %1\n"
+ : "+A" (old), "+m" (*ptr)
+ : "b" (low), "c" (high)
+ );
+ return old;
+}
+
+u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val)
+{
+ return cmpxchg8b(&ptr->counter, old_val, new_val);
+}
+EXPORT_SYMBOL(atomic64_cmpxchg);
+
+/**
+ * atomic64_xchg - xchg atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ * @new_val: value to assign
+ *
+ * Atomically xchgs the value of @ptr to @new_val and returns
+ * the old value.
+ */
+u64 atomic64_xchg(atomic64_t *ptr, u64 new_val)
+{
+ /*
+ * Try first with a (possibly incorrect) assumption about
+ * what we have there. We'll do two loops most likely,
+ * but we'll get an ownership MESI transaction straight away
+ * instead of a read transaction followed by a
+ * flush-for-ownership transaction:
+ */
+ u64 old_val, real_val = 0;
+
+ do {
+ old_val = real_val;
+
+ real_val = atomic64_cmpxchg(ptr, old_val, new_val);
+
+ } while (real_val != old_val);
+
+ return old_val;
+}
+EXPORT_SYMBOL(atomic64_xchg);
+
+/**
+ * atomic64_set - set atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ * @new_val: value to assign
+ *
+ * Atomically sets the value of @ptr to @new_val.
+ */
+void atomic64_set(atomic64_t *ptr, u64 new_val)
+{
+ atomic64_xchg(ptr, new_val);
+}
+EXPORT_SYMBOL(atomic64_set);
+
+/**
+EXPORT_SYMBOL(atomic64_read);
+ * atomic64_add_return - add and return
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns @delta + *@ptr
+ */
+noinline u64 atomic64_add_return(u64 delta, atomic64_t *ptr)
+{
+ /*
+ * Try first with a (possibly incorrect) assumption about
+ * what we have there. We'll do two loops most likely,
+ * but we'll get an ownership MESI transaction straight away
+ * instead of a read transaction followed by a
+ * flush-for-ownership transaction:
+ */
+ u64 old_val, new_val, real_val = 0;
+
+ do {
+ old_val = real_val;
+ new_val = old_val + delta;
+
+ real_val = atomic64_cmpxchg(ptr, old_val, new_val);
+
+ } while (real_val != old_val);
+
+ return new_val;
+}
+EXPORT_SYMBOL(atomic64_add_return);
+
+u64 atomic64_sub_return(u64 delta, atomic64_t *ptr)
+{
+ return atomic64_add_return(-delta, ptr);
+}
+EXPORT_SYMBOL(atomic64_sub_return);
+
+u64 atomic64_inc_return(atomic64_t *ptr)
+{
+ return atomic64_add_return(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_inc_return);
+
+u64 atomic64_dec_return(atomic64_t *ptr)
+{
+ return atomic64_sub_return(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_dec_return);
+
+/**
+ * atomic64_add - add integer to atomic64 variable
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr.
+ */
+void atomic64_add(u64 delta, atomic64_t *ptr)
+{
+ atomic64_add_return(delta, ptr);
+}
+EXPORT_SYMBOL(atomic64_add);
+
+/**
+ * atomic64_sub - subtract the atomic64 variable
+ * @delta: integer value to subtract
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr.
+ */
+void atomic64_sub(u64 delta, atomic64_t *ptr)
+{
+ atomic64_add(-delta, ptr);
+}
+EXPORT_SYMBOL(atomic64_sub);
+
+/**
+ * atomic64_sub_and_test - subtract value from variable and test result
+ * @delta: integer value to subtract
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr and returns
+ * true if the result is zero, or false for all
+ * other cases.
+ */
+int atomic64_sub_and_test(u64 delta, atomic64_t *ptr)
+{
+ u64 new_val = atomic64_sub_return(delta, ptr);
+
+ return new_val == 0;
+}
+EXPORT_SYMBOL(atomic64_sub_and_test);
+
+/**
+ * atomic64_inc - increment atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1.
+ */
+void atomic64_inc(atomic64_t *ptr)
+{
+ atomic64_add(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_inc);
+
+/**
+ * atomic64_dec - decrement atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1.
+ */
+void atomic64_dec(atomic64_t *ptr)
+{
+ atomic64_sub(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_dec);
+
+/**
+ * atomic64_dec_and_test - decrement and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases.
+ */
+int atomic64_dec_and_test(atomic64_t *ptr)
+{
+ return atomic64_sub_and_test(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_dec_and_test);
+
+/**
+ * atomic64_inc_and_test - increment and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+int atomic64_inc_and_test(atomic64_t *ptr)
+{
+ return atomic64_sub_and_test(-1, ptr);
+}
+EXPORT_SYMBOL(atomic64_inc_and_test);
+
+/**
+ * atomic64_add_negative - add and test if negative
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns true
+ * if the result is negative, or false when
+ * result is greater than or equal to zero.
+ */
+int atomic64_add_negative(u64 delta, atomic64_t *ptr)
+{
+ s64 new_val = atomic64_add_return(delta, ptr);
+
+ return new_val < 0;
+}
+EXPORT_SYMBOL(atomic64_add_negative);