diff options
Diffstat (limited to 'include/linux/percpu-defs.h')
-rw-r--r-- | include/linux/percpu-defs.h | 94 |
1 files changed, 42 insertions, 52 deletions
diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index 176bfbd52d97..c16cdeaa505e 100644 --- a/include/linux/percpu-defs.h +++ b/include/linux/percpu-defs.h @@ -26,13 +26,11 @@ #define PER_CPU_SHARED_ALIGNED_SECTION "..shared_aligned" #define PER_CPU_ALIGNED_SECTION "..shared_aligned" #endif -#define PER_CPU_FIRST_SECTION "..first" #else #define PER_CPU_SHARED_ALIGNED_SECTION "" #define PER_CPU_ALIGNED_SECTION "..shared_aligned" -#define PER_CPU_FIRST_SECTION "" #endif @@ -51,7 +49,7 @@ PER_CPU_ATTRIBUTES #define __PCPU_DUMMY_ATTRS \ - __attribute__((section(".discard"), unused)) + __section(".discard") __attribute__((unused)) /* * s390 and alpha modules require percpu variables to be defined as @@ -115,14 +113,17 @@ DEFINE_PER_CPU_SECTION(type, name, "") /* - * Declaration/definition used for per-CPU variables that must come first in - * the set of variables. + * Declaration/definition used for per-CPU variables that are frequently + * accessed and should be in a single cacheline. + * + * For use only by architecture and core code. Only use scalar or pointer + * types to maximize density. */ -#define DECLARE_PER_CPU_FIRST(type, name) \ - DECLARE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION) +#define DECLARE_PER_CPU_CACHE_HOT(type, name) \ + DECLARE_PER_CPU_SECTION(type, name, "..hot.." #name) -#define DEFINE_PER_CPU_FIRST(type, name) \ - DEFINE_PER_CPU_SECTION(type, name, PER_CPU_FIRST_SECTION) +#define DEFINE_PER_CPU_CACHE_HOT(type, name) \ + DEFINE_PER_CPU_SECTION(type, name, "..hot.." #name) /* * Declaration/definition used for per-CPU variables that must be cacheline @@ -220,15 +221,17 @@ do { \ (void)__vpp_verify; \ } while (0) +#define PERCPU_PTR(__p) \ + (TYPEOF_UNQUAL(*(__p)) __force __kernel *)((__force unsigned long)(__p)) + #ifdef CONFIG_SMP /* - * Add an offset to a pointer but keep the pointer as-is. Use RELOC_HIDE() - * to prevent the compiler from making incorrect assumptions about the - * pointer value. The weird cast keeps both GCC and sparse happy. + * Add an offset to a pointer. Use RELOC_HIDE() to prevent the compiler + * from making incorrect assumptions about the pointer value. */ #define SHIFT_PERCPU_PTR(__p, __offset) \ - RELOC_HIDE((typeof(*(__p)) __kernel __force *)(__p), (__offset)) + RELOC_HIDE(PERCPU_PTR(__p), (__offset)) #define per_cpu_ptr(ptr, cpu) \ ({ \ @@ -254,13 +257,13 @@ do { \ #else /* CONFIG_SMP */ -#define VERIFY_PERCPU_PTR(__p) \ +#define per_cpu_ptr(ptr, cpu) \ ({ \ - __verify_pcpu_ptr(__p); \ - (typeof(*(__p)) __kernel __force *)(__p); \ + (void)(cpu); \ + __verify_pcpu_ptr(ptr); \ + PERCPU_PTR(ptr); \ }) -#define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); VERIFY_PERCPU_PTR(ptr); }) #define raw_cpu_ptr(ptr) per_cpu_ptr(ptr, 0) #define this_cpu_ptr(ptr) raw_cpu_ptr(ptr) @@ -310,12 +313,12 @@ extern void __bad_size_call_parameter(void); #ifdef CONFIG_DEBUG_PREEMPT extern void __this_cpu_preempt_check(const char *op); #else -static inline void __this_cpu_preempt_check(const char *op) { } +static __always_inline void __this_cpu_preempt_check(const char *op) { } #endif #define __pcpu_size_call_return(stem, variable) \ ({ \ - typeof(variable) pscr_ret__; \ + TYPEOF_UNQUAL(variable) pscr_ret__; \ __verify_pcpu_ptr(&(variable)); \ switch(sizeof(variable)) { \ case 1: pscr_ret__ = stem##1(variable); break; \ @@ -330,7 +333,7 @@ static inline void __this_cpu_preempt_check(const char *op) { } #define __pcpu_size_call_return2(stem, variable, ...) \ ({ \ - typeof(variable) pscr2_ret__; \ + TYPEOF_UNQUAL(variable) pscr2_ret__; \ __verify_pcpu_ptr(&(variable)); \ switch(sizeof(variable)) { \ case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \ @@ -343,31 +346,19 @@ static inline void __this_cpu_preempt_check(const char *op) { } pscr2_ret__; \ }) -/* - * Special handling for cmpxchg_double. cmpxchg_double is passed two - * percpu variables. The first has to be aligned to a double word - * boundary and the second has to follow directly thereafter. - * We enforce this on all architectures even if they don't support - * a double cmpxchg instruction, since it's a cheap requirement, and it - * avoids breaking the requirement for architectures with the instruction. - */ -#define __pcpu_double_call_return_bool(stem, pcp1, pcp2, ...) \ +#define __pcpu_size_call_return2bool(stem, variable, ...) \ ({ \ - bool pdcrb_ret__; \ - __verify_pcpu_ptr(&(pcp1)); \ - BUILD_BUG_ON(sizeof(pcp1) != sizeof(pcp2)); \ - VM_BUG_ON((unsigned long)(&(pcp1)) % (2 * sizeof(pcp1))); \ - VM_BUG_ON((unsigned long)(&(pcp2)) != \ - (unsigned long)(&(pcp1)) + sizeof(pcp1)); \ - switch(sizeof(pcp1)) { \ - case 1: pdcrb_ret__ = stem##1(pcp1, pcp2, __VA_ARGS__); break; \ - case 2: pdcrb_ret__ = stem##2(pcp1, pcp2, __VA_ARGS__); break; \ - case 4: pdcrb_ret__ = stem##4(pcp1, pcp2, __VA_ARGS__); break; \ - case 8: pdcrb_ret__ = stem##8(pcp1, pcp2, __VA_ARGS__); break; \ + bool pscr2_ret__; \ + __verify_pcpu_ptr(&(variable)); \ + switch(sizeof(variable)) { \ + case 1: pscr2_ret__ = stem##1(variable, __VA_ARGS__); break; \ + case 2: pscr2_ret__ = stem##2(variable, __VA_ARGS__); break; \ + case 4: pscr2_ret__ = stem##4(variable, __VA_ARGS__); break; \ + case 8: pscr2_ret__ = stem##8(variable, __VA_ARGS__); break; \ default: \ __bad_size_call_parameter(); break; \ } \ - pdcrb_ret__; \ + pscr2_ret__; \ }) #define __pcpu_size_call(stem, variable, ...) \ @@ -384,7 +375,7 @@ do { \ } while (0) /* - * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@linux.com> + * this_cpu operations (C) 2008-2013 Christoph Lameter <cl@gentwo.org> * * Optimized manipulation for memory allocated through the per cpu * allocator or for addresses of per cpu variables. @@ -412,7 +403,7 @@ do { \ * instead. * * If there is no other protection through preempt disable and/or disabling - * interupts then one of these RMW operations can show unexpected behavior + * interrupts then one of these RMW operations can show unexpected behavior * because the execution thread was rescheduled on another processor or an * interrupt occurred and the same percpu variable was modified from the * interrupt context. @@ -426,9 +417,8 @@ do { \ #define raw_cpu_xchg(pcp, nval) __pcpu_size_call_return2(raw_cpu_xchg_, pcp, nval) #define raw_cpu_cmpxchg(pcp, oval, nval) \ __pcpu_size_call_return2(raw_cpu_cmpxchg_, pcp, oval, nval) -#define raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - __pcpu_double_call_return_bool(raw_cpu_cmpxchg_double_, pcp1, pcp2, oval1, oval2, nval1, nval2) - +#define raw_cpu_try_cmpxchg(pcp, ovalp, nval) \ + __pcpu_size_call_return2bool(raw_cpu_try_cmpxchg_, pcp, ovalp, nval) #define raw_cpu_sub(pcp, val) raw_cpu_add(pcp, -(val)) #define raw_cpu_inc(pcp) raw_cpu_add(pcp, 1) #define raw_cpu_dec(pcp) raw_cpu_sub(pcp, 1) @@ -488,9 +478,10 @@ do { \ raw_cpu_cmpxchg(pcp, oval, nval); \ }) -#define __this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ -({ __this_cpu_preempt_check("cmpxchg_double"); \ - raw_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2); \ +#define __this_cpu_try_cmpxchg(pcp, ovalp, nval) \ +({ \ + __this_cpu_preempt_check("try_cmpxchg"); \ + raw_cpu_try_cmpxchg(pcp, ovalp, nval); \ }) #define __this_cpu_sub(pcp, val) __this_cpu_add(pcp, -(typeof(pcp))(val)) @@ -513,9 +504,8 @@ do { \ #define this_cpu_xchg(pcp, nval) __pcpu_size_call_return2(this_cpu_xchg_, pcp, nval) #define this_cpu_cmpxchg(pcp, oval, nval) \ __pcpu_size_call_return2(this_cpu_cmpxchg_, pcp, oval, nval) -#define this_cpu_cmpxchg_double(pcp1, pcp2, oval1, oval2, nval1, nval2) \ - __pcpu_double_call_return_bool(this_cpu_cmpxchg_double_, pcp1, pcp2, oval1, oval2, nval1, nval2) - +#define this_cpu_try_cmpxchg(pcp, ovalp, nval) \ + __pcpu_size_call_return2bool(this_cpu_try_cmpxchg_, pcp, ovalp, nval) #define this_cpu_sub(pcp, val) this_cpu_add(pcp, -(typeof(pcp))(val)) #define this_cpu_inc(pcp) this_cpu_add(pcp, 1) #define this_cpu_dec(pcp) this_cpu_sub(pcp, 1) |