diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/power7-pmu.c | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/atomic_32.h | 185 | ||||
| -rw-r--r-- | arch/x86/include/asm/atomic_64.h | 42 | ||||
| -rw-r--r-- | arch/x86/include/asm/stacktrace.h | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/perf_counter.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/dumpstack_32.c | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/dumpstack_64.c | 22 | ||||
| -rw-r--r-- | arch/x86/lib/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/lib/atomic64_32.c | 230 |
9 files changed, 353 insertions, 144 deletions
diff --git a/arch/powerpc/kernel/power7-pmu.c b/arch/powerpc/kernel/power7-pmu.c index 5d755ef7ac8f..5a9f5cbd40a4 100644 --- a/arch/powerpc/kernel/power7-pmu.c +++ b/arch/powerpc/kernel/power7-pmu.c @@ -358,6 +358,7 @@ static struct power_pmu power7_pmu = { .get_constraint = power7_get_constraint, .get_alternatives = power7_get_alternatives, .disable_pmc = power7_disable_pmc, + .flags = PPMU_ALT_SIPR, .n_generic = ARRAY_SIZE(power7_generic_events), .generic_events = power7_generic_events, .cache_events = &power7_cache_events, 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); |
