123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459 |
- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef _ASM_X86_PERCPU_H
- #define _ASM_X86_PERCPU_H
- #ifdef CONFIG_X86_64
- #define __percpu_seg gs
- #else
- #define __percpu_seg fs
- #endif
- #ifdef __ASSEMBLY__
- #ifdef CONFIG_SMP
- #define PER_CPU_VAR(var) %__percpu_seg:var
- #else /* ! SMP */
- #define PER_CPU_VAR(var) var
- #endif /* SMP */
- #ifdef CONFIG_X86_64_SMP
- #define INIT_PER_CPU_VAR(var) init_per_cpu__##var
- #else
- #define INIT_PER_CPU_VAR(var) var
- #endif
- #else /* ...!ASSEMBLY */
- #include <linux/kernel.h>
- #include <linux/stringify.h>
- #ifdef CONFIG_SMP
- #define __percpu_prefix "%%"__stringify(__percpu_seg)":"
- #define __my_cpu_offset this_cpu_read(this_cpu_off)
- /*
- * Compared to the generic __my_cpu_offset version, the following
- * saves one instruction and avoids clobbering a temp register.
- */
- #define arch_raw_cpu_ptr(ptr) \
- ({ \
- unsigned long tcp_ptr__; \
- asm ("add " __percpu_arg(1) ", %0" \
- : "=r" (tcp_ptr__) \
- : "m" (this_cpu_off), "0" (ptr)); \
- (typeof(*(ptr)) __kernel __force *)tcp_ptr__; \
- })
- #else
- #define __percpu_prefix ""
- #endif
- #define __percpu_arg(x) __percpu_prefix "%" #x
- /*
- * Initialized pointers to per-cpu variables needed for the boot
- * processor need to use these macros to get the proper address
- * offset from __per_cpu_load on SMP.
- *
- * There also must be an entry in vmlinux_64.lds.S
- */
- #define DECLARE_INIT_PER_CPU(var) \
- extern typeof(var) init_per_cpu_var(var)
- #ifdef CONFIG_X86_64_SMP
- #define init_per_cpu_var(var) init_per_cpu__##var
- #else
- #define init_per_cpu_var(var) var
- #endif
- /* For arch-specific code, we can use direct single-insn ops (they
- * don't give an lvalue though). */
- #define __pcpu_type_1 u8
- #define __pcpu_type_2 u16
- #define __pcpu_type_4 u32
- #define __pcpu_type_8 u64
- #define __pcpu_cast_1(val) ((u8)(((unsigned long) val) & 0xff))
- #define __pcpu_cast_2(val) ((u16)(((unsigned long) val) & 0xffff))
- #define __pcpu_cast_4(val) ((u32)(((unsigned long) val) & 0xffffffff))
- #define __pcpu_cast_8(val) ((u64)(val))
- #define __pcpu_op1_1(op, dst) op "b " dst
- #define __pcpu_op1_2(op, dst) op "w " dst
- #define __pcpu_op1_4(op, dst) op "l " dst
- #define __pcpu_op1_8(op, dst) op "q " dst
- #define __pcpu_op2_1(op, src, dst) op "b " src ", " dst
- #define __pcpu_op2_2(op, src, dst) op "w " src ", " dst
- #define __pcpu_op2_4(op, src, dst) op "l " src ", " dst
- #define __pcpu_op2_8(op, src, dst) op "q " src ", " dst
- #define __pcpu_reg_1(mod, x) mod "q" (x)
- #define __pcpu_reg_2(mod, x) mod "r" (x)
- #define __pcpu_reg_4(mod, x) mod "r" (x)
- #define __pcpu_reg_8(mod, x) mod "r" (x)
- #define __pcpu_reg_imm_1(x) "qi" (x)
- #define __pcpu_reg_imm_2(x) "ri" (x)
- #define __pcpu_reg_imm_4(x) "ri" (x)
- #define __pcpu_reg_imm_8(x) "re" (x)
- #define percpu_to_op(size, qual, op, _var, _val) \
- do { \
- __pcpu_type_##size pto_val__ = __pcpu_cast_##size(_val); \
- if (0) { \
- typeof(_var) pto_tmp__; \
- pto_tmp__ = (_val); \
- (void)pto_tmp__; \
- } \
- asm qual(__pcpu_op2_##size(op, "%[val]", __percpu_arg([var])) \
- : [var] "+m" (_var) \
- : [val] __pcpu_reg_imm_##size(pto_val__)); \
- } while (0)
- #define percpu_unary_op(size, qual, op, _var) \
- ({ \
- asm qual (__pcpu_op1_##size(op, __percpu_arg([var])) \
- : [var] "+m" (_var)); \
- })
- /*
- * Generate a percpu add to memory instruction and optimize code
- * if one is added or subtracted.
- */
- #define percpu_add_op(size, qual, var, val) \
- do { \
- const int pao_ID__ = (__builtin_constant_p(val) && \
- ((val) == 1 || (val) == -1)) ? \
- (int)(val) : 0; \
- if (0) { \
- typeof(var) pao_tmp__; \
- pao_tmp__ = (val); \
- (void)pao_tmp__; \
- } \
- if (pao_ID__ == 1) \
- percpu_unary_op(size, qual, "inc", var); \
- else if (pao_ID__ == -1) \
- percpu_unary_op(size, qual, "dec", var); \
- else \
- percpu_to_op(size, qual, "add", var, val); \
- } while (0)
- #define percpu_from_op(size, qual, op, _var) \
- ({ \
- __pcpu_type_##size pfo_val__; \
- asm qual (__pcpu_op2_##size(op, __percpu_arg([var]), "%[val]") \
- : [val] __pcpu_reg_##size("=", pfo_val__) \
- : [var] "m" (_var)); \
- (typeof(_var))(unsigned long) pfo_val__; \
- })
- #define percpu_stable_op(size, op, _var) \
- ({ \
- __pcpu_type_##size pfo_val__; \
- asm(__pcpu_op2_##size(op, __percpu_arg(P[var]), "%[val]") \
- : [val] __pcpu_reg_##size("=", pfo_val__) \
- : [var] "p" (&(_var))); \
- (typeof(_var))(unsigned long) pfo_val__; \
- })
- /*
- * Add return operation
- */
- #define percpu_add_return_op(size, qual, _var, _val) \
- ({ \
- __pcpu_type_##size paro_tmp__ = __pcpu_cast_##size(_val); \
- asm qual (__pcpu_op2_##size("xadd", "%[tmp]", \
- __percpu_arg([var])) \
- : [tmp] __pcpu_reg_##size("+", paro_tmp__), \
- [var] "+m" (_var) \
- : : "memory"); \
- (typeof(_var))(unsigned long) (paro_tmp__ + _val); \
- })
- /*
- * xchg is implemented using cmpxchg without a lock prefix. xchg is
- * expensive due to the implied lock prefix. The processor cannot prefetch
- * cachelines if xchg is used.
- */
- #define percpu_xchg_op(size, qual, _var, _nval) \
- ({ \
- __pcpu_type_##size pxo_old__; \
- __pcpu_type_##size pxo_new__ = __pcpu_cast_##size(_nval); \
- asm qual (__pcpu_op2_##size("mov", __percpu_arg([var]), \
- "%[oval]") \
- "\n1:\t" \
- __pcpu_op2_##size("cmpxchg", "%[nval]", \
- __percpu_arg([var])) \
- "\n\tjnz 1b" \
- : [oval] "=&a" (pxo_old__), \
- [var] "+m" (_var) \
- : [nval] __pcpu_reg_##size(, pxo_new__) \
- : "memory"); \
- (typeof(_var))(unsigned long) pxo_old__; \
- })
- /*
- * cmpxchg has no such implied lock semantics as a result it is much
- * more efficient for cpu local operations.
- */
- #define percpu_cmpxchg_op(size, qual, _var, _oval, _nval) \
- ({ \
- __pcpu_type_##size pco_old__ = __pcpu_cast_##size(_oval); \
- __pcpu_type_##size pco_new__ = __pcpu_cast_##size(_nval); \
- asm qual (__pcpu_op2_##size("cmpxchg", "%[nval]", \
- __percpu_arg([var])) \
- : [oval] "+a" (pco_old__), \
- [var] "+m" (_var) \
- : [nval] __pcpu_reg_##size(, pco_new__) \
- : "memory"); \
- (typeof(_var))(unsigned long) pco_old__; \
- })
- /*
- * this_cpu_read() makes gcc load the percpu variable every time it is
- * accessed while this_cpu_read_stable() allows the value to be cached.
- * this_cpu_read_stable() is more efficient and can be used if its value
- * is guaranteed to be valid across cpus. The current users include
- * get_current() and get_thread_info() both of which are actually
- * per-thread variables implemented as per-cpu variables and thus
- * stable for the duration of the respective task.
- */
- #define this_cpu_read_stable_1(pcp) percpu_stable_op(1, "mov", pcp)
- #define this_cpu_read_stable_2(pcp) percpu_stable_op(2, "mov", pcp)
- #define this_cpu_read_stable_4(pcp) percpu_stable_op(4, "mov", pcp)
- #define this_cpu_read_stable_8(pcp) percpu_stable_op(8, "mov", pcp)
- #define this_cpu_read_stable(pcp) __pcpu_size_call_return(this_cpu_read_stable_, pcp)
- #define raw_cpu_read_1(pcp) percpu_from_op(1, , "mov", pcp)
- #define raw_cpu_read_2(pcp) percpu_from_op(2, , "mov", pcp)
- #define raw_cpu_read_4(pcp) percpu_from_op(4, , "mov", pcp)
- #define raw_cpu_write_1(pcp, val) percpu_to_op(1, , "mov", (pcp), val)
- #define raw_cpu_write_2(pcp, val) percpu_to_op(2, , "mov", (pcp), val)
- #define raw_cpu_write_4(pcp, val) percpu_to_op(4, , "mov", (pcp), val)
- #define raw_cpu_add_1(pcp, val) percpu_add_op(1, , (pcp), val)
- #define raw_cpu_add_2(pcp, val) percpu_add_op(2, , (pcp), val)
- #define raw_cpu_add_4(pcp, val) percpu_add_op(4, , (pcp), val)
- #define raw_cpu_and_1(pcp, val) percpu_to_op(1, , "and", (pcp), val)
- #define raw_cpu_and_2(pcp, val) percpu_to_op(2, , "and", (pcp), val)
- #define raw_cpu_and_4(pcp, val) percpu_to_op(4, , "and", (pcp), val)
- #define raw_cpu_or_1(pcp, val) percpu_to_op(1, , "or", (pcp), val)
- #define raw_cpu_or_2(pcp, val) percpu_to_op(2, , "or", (pcp), val)
- #define raw_cpu_or_4(pcp, val) percpu_to_op(4, , "or", (pcp), val)
- /*
- * raw_cpu_xchg() can use a load-store since it is not required to be
- * IRQ-safe.
- */
- #define raw_percpu_xchg_op(var, nval) \
- ({ \
- typeof(var) pxo_ret__ = raw_cpu_read(var); \
- raw_cpu_write(var, (nval)); \
- pxo_ret__; \
- })
- #define raw_cpu_xchg_1(pcp, val) raw_percpu_xchg_op(pcp, val)
- #define raw_cpu_xchg_2(pcp, val) raw_percpu_xchg_op(pcp, val)
- #define raw_cpu_xchg_4(pcp, val) raw_percpu_xchg_op(pcp, val)
- #define this_cpu_read_1(pcp) percpu_from_op(1, volatile, "mov", pcp)
- #define this_cpu_read_2(pcp) percpu_from_op(2, volatile, "mov", pcp)
- #define this_cpu_read_4(pcp) percpu_from_op(4, volatile, "mov", pcp)
- #define this_cpu_write_1(pcp, val) percpu_to_op(1, volatile, "mov", (pcp), val)
- #define this_cpu_write_2(pcp, val) percpu_to_op(2, volatile, "mov", (pcp), val)
- #define this_cpu_write_4(pcp, val) percpu_to_op(4, volatile, "mov", (pcp), val)
- #define this_cpu_add_1(pcp, val) percpu_add_op(1, volatile, (pcp), val)
- #define this_cpu_add_2(pcp, val) percpu_add_op(2, volatile, (pcp), val)
- #define this_cpu_add_4(pcp, val) percpu_add_op(4, volatile, (pcp), val)
- #define this_cpu_and_1(pcp, val) percpu_to_op(1, volatile, "and", (pcp), val)
- #define this_cpu_and_2(pcp, val) percpu_to_op(2, volatile, "and", (pcp), val)
- #define this_cpu_and_4(pcp, val) percpu_to_op(4, volatile, "and", (pcp), val)
- #define this_cpu_or_1(pcp, val) percpu_to_op(1, volatile, "or", (pcp), val)
- #define this_cpu_or_2(pcp, val) percpu_to_op(2, volatile, "or", (pcp), val)
- #define this_cpu_or_4(pcp, val) percpu_to_op(4, volatile, "or", (pcp), val)
- #define this_cpu_xchg_1(pcp, nval) percpu_xchg_op(1, volatile, pcp, nval)
- #define this_cpu_xchg_2(pcp, nval) percpu_xchg_op(2, volatile, pcp, nval)
- #define this_cpu_xchg_4(pcp, nval) percpu_xchg_op(4, volatile, pcp, nval)
- #define raw_cpu_add_return_1(pcp, val) percpu_add_return_op(1, , pcp, val)
- #define raw_cpu_add_return_2(pcp, val) percpu_add_return_op(2, , pcp, val)
- #define raw_cpu_add_return_4(pcp, val) percpu_add_return_op(4, , pcp, val)
- #define raw_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(1, , pcp, oval, nval)
- #define raw_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(2, , pcp, oval, nval)
- #define raw_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(4, , pcp, oval, nval)
- #define this_cpu_add_return_1(pcp, val) percpu_add_return_op(1, volatile, pcp, val)
- #define this_cpu_add_return_2(pcp, val) percpu_add_return_op(2, volatile, pcp, val)
- #define this_cpu_add_return_4(pcp, val) percpu_add_return_op(4, volatile, pcp, val)
- #define this_cpu_cmpxchg_1(pcp, oval, nval) percpu_cmpxchg_op(1, volatile, pcp, oval, nval)
- #define this_cpu_cmpxchg_2(pcp, oval, nval) percpu_cmpxchg_op(2, volatile, pcp, oval, nval)
- #define this_cpu_cmpxchg_4(pcp, oval, nval) percpu_cmpxchg_op(4, volatile, pcp, oval, nval)
- #ifdef CONFIG_X86_CMPXCHG64
- #define percpu_cmpxchg8b_double(pcp1, pcp2, o1, o2, n1, n2) \
- ({ \
- bool __ret; \
- typeof(pcp1) __o1 = (o1), __n1 = (n1); \
- typeof(pcp2) __o2 = (o2), __n2 = (n2); \
- asm volatile("cmpxchg8b "__percpu_arg(1) \
- CC_SET(z) \
- : CC_OUT(z) (__ret), "+m" (pcp1), "+m" (pcp2), "+a" (__o1), "+d" (__o2) \
- : "b" (__n1), "c" (__n2)); \
- __ret; \
- })
- #define raw_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
- #define this_cpu_cmpxchg_double_4 percpu_cmpxchg8b_double
- #endif /* CONFIG_X86_CMPXCHG64 */
- /*
- * Per cpu atomic 64 bit operations are only available under 64 bit.
- * 32 bit must fall back to generic operations.
- */
- #ifdef CONFIG_X86_64
- #define raw_cpu_read_8(pcp) percpu_from_op(8, , "mov", pcp)
- #define raw_cpu_write_8(pcp, val) percpu_to_op(8, , "mov", (pcp), val)
- #define raw_cpu_add_8(pcp, val) percpu_add_op(8, , (pcp), val)
- #define raw_cpu_and_8(pcp, val) percpu_to_op(8, , "and", (pcp), val)
- #define raw_cpu_or_8(pcp, val) percpu_to_op(8, , "or", (pcp), val)
- #define raw_cpu_add_return_8(pcp, val) percpu_add_return_op(8, , pcp, val)
- #define raw_cpu_xchg_8(pcp, nval) raw_percpu_xchg_op(pcp, nval)
- #define raw_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(8, , pcp, oval, nval)
- #define this_cpu_read_8(pcp) percpu_from_op(8, volatile, "mov", pcp)
- #define this_cpu_write_8(pcp, val) percpu_to_op(8, volatile, "mov", (pcp), val)
- #define this_cpu_add_8(pcp, val) percpu_add_op(8, volatile, (pcp), val)
- #define this_cpu_and_8(pcp, val) percpu_to_op(8, volatile, "and", (pcp), val)
- #define this_cpu_or_8(pcp, val) percpu_to_op(8, volatile, "or", (pcp), val)
- #define this_cpu_add_return_8(pcp, val) percpu_add_return_op(8, volatile, pcp, val)
- #define this_cpu_xchg_8(pcp, nval) percpu_xchg_op(8, volatile, pcp, nval)
- #define this_cpu_cmpxchg_8(pcp, oval, nval) percpu_cmpxchg_op(8, volatile, pcp, oval, nval)
- /*
- * Pretty complex macro to generate cmpxchg16 instruction. The instruction
- * is not supported on early AMD64 processors so we must be able to emulate
- * it in software. The address used in the cmpxchg16 instruction must be
- * aligned to a 16 byte boundary.
- */
- #define percpu_cmpxchg16b_double(pcp1, pcp2, o1, o2, n1, n2) \
- ({ \
- bool __ret; \
- typeof(pcp1) __o1 = (o1), __n1 = (n1); \
- typeof(pcp2) __o2 = (o2), __n2 = (n2); \
- alternative_io("leaq %P1,%%rsi\n\tcall this_cpu_cmpxchg16b_emu\n\t", \
- "cmpxchg16b " __percpu_arg(1) "\n\tsetz %0\n\t", \
- X86_FEATURE_CX16, \
- ASM_OUTPUT2("=a" (__ret), "+m" (pcp1), \
- "+m" (pcp2), "+d" (__o2)), \
- "b" (__n1), "c" (__n2), "a" (__o1) : "rsi"); \
- __ret; \
- })
- #define raw_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
- #define this_cpu_cmpxchg_double_8 percpu_cmpxchg16b_double
- #endif
- static __always_inline bool x86_this_cpu_constant_test_bit(unsigned int nr,
- const unsigned long __percpu *addr)
- {
- unsigned long __percpu *a =
- (unsigned long __percpu *)addr + nr / BITS_PER_LONG;
- #ifdef CONFIG_X86_64
- return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_8(*a)) != 0;
- #else
- return ((1UL << (nr % BITS_PER_LONG)) & raw_cpu_read_4(*a)) != 0;
- #endif
- }
- static inline bool x86_this_cpu_variable_test_bit(int nr,
- const unsigned long __percpu *addr)
- {
- bool oldbit;
- asm volatile("btl "__percpu_arg(2)",%1"
- CC_SET(c)
- : CC_OUT(c) (oldbit)
- : "m" (*(unsigned long __percpu *)addr), "Ir" (nr));
- return oldbit;
- }
- #define x86_this_cpu_test_bit(nr, addr) \
- (__builtin_constant_p((nr)) \
- ? x86_this_cpu_constant_test_bit((nr), (addr)) \
- : x86_this_cpu_variable_test_bit((nr), (addr)))
- #include <asm-generic/percpu.h>
- /* We can use this directly for local CPU (faster). */
- DECLARE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off);
- #endif /* !__ASSEMBLY__ */
- #ifdef CONFIG_SMP
- /*
- * Define the "EARLY_PER_CPU" macros. These are used for some per_cpu
- * variables that are initialized and accessed before there are per_cpu
- * areas allocated.
- */
- #define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
- DEFINE_PER_CPU(_type, _name) = _initvalue; \
- __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
- { [0 ... NR_CPUS-1] = _initvalue }; \
- __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
- #define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
- DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue; \
- __typeof__(_type) _name##_early_map[NR_CPUS] __initdata = \
- { [0 ... NR_CPUS-1] = _initvalue }; \
- __typeof__(_type) *_name##_early_ptr __refdata = _name##_early_map
- #define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
- EXPORT_PER_CPU_SYMBOL(_name)
- #define DECLARE_EARLY_PER_CPU(_type, _name) \
- DECLARE_PER_CPU(_type, _name); \
- extern __typeof__(_type) *_name##_early_ptr; \
- extern __typeof__(_type) _name##_early_map[]
- #define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
- DECLARE_PER_CPU_READ_MOSTLY(_type, _name); \
- extern __typeof__(_type) *_name##_early_ptr; \
- extern __typeof__(_type) _name##_early_map[]
- #define early_per_cpu_ptr(_name) (_name##_early_ptr)
- #define early_per_cpu_map(_name, _idx) (_name##_early_map[_idx])
- #define early_per_cpu(_name, _cpu) \
- *(early_per_cpu_ptr(_name) ? \
- &early_per_cpu_ptr(_name)[_cpu] : \
- &per_cpu(_name, _cpu))
- #else /* !CONFIG_SMP */
- #define DEFINE_EARLY_PER_CPU(_type, _name, _initvalue) \
- DEFINE_PER_CPU(_type, _name) = _initvalue
- #define DEFINE_EARLY_PER_CPU_READ_MOSTLY(_type, _name, _initvalue) \
- DEFINE_PER_CPU_READ_MOSTLY(_type, _name) = _initvalue
- #define EXPORT_EARLY_PER_CPU_SYMBOL(_name) \
- EXPORT_PER_CPU_SYMBOL(_name)
- #define DECLARE_EARLY_PER_CPU(_type, _name) \
- DECLARE_PER_CPU(_type, _name)
- #define DECLARE_EARLY_PER_CPU_READ_MOSTLY(_type, _name) \
- DECLARE_PER_CPU_READ_MOSTLY(_type, _name)
- #define early_per_cpu(_name, _cpu) per_cpu(_name, _cpu)
- #define early_per_cpu_ptr(_name) NULL
- /* no early_per_cpu_map() */
- #endif /* !CONFIG_SMP */
- #endif /* _ASM_X86_PERCPU_H */
|