/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (C) 2013 ARM Ltd. */ #ifndef __ASM_PERCPU_H #define __ASM_PERCPU_H #include #include #include #include #include static inline void set_my_cpu_offset(unsigned long off) { asm volatile(ALTERNATIVE("msr tpidr_el1, %0", "msr tpidr_el2, %0", ARM64_HAS_VIRT_HOST_EXTN) :: "r" (off) : "memory"); } static inline unsigned long __hyp_my_cpu_offset(void) { /* * Non-VHE hyp code runs with preemption disabled. No need to hazard * the register access against barrier() as in __kern_my_cpu_offset. */ return read_sysreg(tpidr_el2); } static inline unsigned long __kern_my_cpu_offset(void) { unsigned long off; /* * We want to allow caching the value, so avoid using volatile and * instead use a fake stack read to hazard against barrier(). */ asm(ALTERNATIVE("mrs %0, tpidr_el1", "mrs %0, tpidr_el2", ARM64_HAS_VIRT_HOST_EXTN) : "=r" (off) : "Q" (*(const unsigned long *)current_stack_pointer)); return off; } #ifdef __KVM_NVHE_HYPERVISOR__ #define __my_cpu_offset __hyp_my_cpu_offset() #else #define __my_cpu_offset __kern_my_cpu_offset() #endif #define PERCPU_RW_OPS(sz) \ static inline unsigned long __percpu_read_##sz(void *ptr) \ { \ return READ_ONCE(*(u##sz *)ptr); \ } \ \ static inline void __percpu_write_##sz(void *ptr, unsigned long val) \ { \ WRITE_ONCE(*(u##sz *)ptr, (u##sz)val); \ } #define __PERCPU_OP_CASE(w, sfx, name, sz, op_llsc, op_lse) \ static inline void \ __percpu_##name##_case_##sz(void *ptr, unsigned long val) \ { \ unsigned int loop; \ u##sz tmp; \ \ asm volatile (ARM64_LSE_ATOMIC_INSN( \ /* LL/SC */ \ "1: ldxr" #sfx "\t%" #w "[tmp], %[ptr]\n" \ #op_llsc "\t%" #w "[tmp], %" #w "[tmp], %" #w "[val]\n" \ " stxr" #sfx "\t%w[loop], %" #w "[tmp], %[ptr]\n" \ " cbnz %w[loop], 1b", \ /* LSE atomics */ \ #op_lse "\t%" #w "[val], %[ptr]\n" \ __nops(3)) \ : [loop] "=&r" (loop), [tmp] "=&r" (tmp), \ [ptr] "+Q"(*(u##sz *)ptr) \ : [val] "r" ((u##sz)(val))); \ } #define __PERCPU_RET_OP_CASE(w, sfx, name, sz, op_llsc, op_lse) \ static inline u##sz \ __percpu_##name##_return_case_##sz(void *ptr, unsigned long val) \ { \ unsigned int loop; \ u##sz ret; \ \ asm volatile (ARM64_LSE_ATOMIC_INSN( \ /* LL/SC */ \ "1: ldxr" #sfx "\t%" #w "[ret], %[ptr]\n" \ #op_llsc "\t%" #w "[ret], %" #w "[ret], %" #w "[val]\n" \ " stxr" #sfx "\t%w[loop], %" #w "[ret], %[ptr]\n" \ " cbnz %w[loop], 1b", \ /* LSE atomics */ \ #op_lse "\t%" #w "[val], %" #w "[ret], %[ptr]\n" \ #op_llsc "\t%" #w "[ret], %" #w "[ret], %" #w "[val]\n" \ __nops(2)) \ : [loop] "=&r" (loop), [ret] "=&r" (ret), \ [ptr] "+Q"(*(u##sz *)ptr) \ : [val] "r" ((u##sz)(val))); \ \ return ret; \ } #define PERCPU_OP(name, op_llsc, op_lse) \ __PERCPU_OP_CASE(w, b, name, 8, op_llsc, op_lse) \ __PERCPU_OP_CASE(w, h, name, 16, op_llsc, op_lse) \ __PERCPU_OP_CASE(w, , name, 32, op_llsc, op_lse) \ __PERCPU_OP_CASE( , , name, 64, op_llsc, op_lse) #define PERCPU_RET_OP(name, op_llsc, op_lse) \ __PERCPU_RET_OP_CASE(w, b, name, 8, op_llsc, op_lse) \ __PERCPU_RET_OP_CASE(w, h, name, 16, op_llsc, op_lse) \ __PERCPU_RET_OP_CASE(w, , name, 32, op_llsc, op_lse) \ __PERCPU_RET_OP_CASE( , , name, 64, op_llsc, op_lse) PERCPU_RW_OPS(8) PERCPU_RW_OPS(16) PERCPU_RW_OPS(32) PERCPU_RW_OPS(64) PERCPU_OP(add, add, stadd) PERCPU_OP(andnot, bic, stclr) PERCPU_OP(or, orr, stset) PERCPU_RET_OP(add, add, ldadd) #undef PERCPU_RW_OPS #undef __PERCPU_OP_CASE #undef __PERCPU_RET_OP_CASE #undef PERCPU_OP #undef PERCPU_RET_OP /* * It would be nice to avoid the conditional call into the scheduler when * re-enabling preemption for preemptible kernels, but doing that in a way * which builds inside a module would mean messing directly with the preempt * count. If you do this, peterz and tglx will hunt you down. * * Not to mention it'll break the actual preemption model for missing a * preemption point when TIF_NEED_RESCHED gets set while preemption is * disabled. */ #define _pcp_protect(op, pcp, ...) \ ({ \ preempt_disable_notrace(); \ op(raw_cpu_ptr(&(pcp)), __VA_ARGS__); \ preempt_enable_notrace(); \ }) #define _pcp_protect_return(op, pcp, args...) \ ({ \ typeof(pcp) __retval; \ preempt_disable_notrace(); \ __retval = (typeof(pcp))op(raw_cpu_ptr(&(pcp)), ##args); \ preempt_enable_notrace(); \ __retval; \ }) #define this_cpu_read_1(pcp) \ _pcp_protect_return(__percpu_read_8, pcp) #define this_cpu_read_2(pcp) \ _pcp_protect_return(__percpu_read_16, pcp) #define this_cpu_read_4(pcp) \ _pcp_protect_return(__percpu_read_32, pcp) #define this_cpu_read_8(pcp) \ _pcp_protect_return(__percpu_read_64, pcp) #define this_cpu_write_1(pcp, val) \ _pcp_protect(__percpu_write_8, pcp, (unsigned long)val) #define this_cpu_write_2(pcp, val) \ _pcp_protect(__percpu_write_16, pcp, (unsigned long)val) #define this_cpu_write_4(pcp, val) \ _pcp_protect(__percpu_write_32, pcp, (unsigned long)val) #define this_cpu_write_8(pcp, val) \ _pcp_protect(__percpu_write_64, pcp, (unsigned long)val) #define this_cpu_add_1(pcp, val) \ _pcp_protect(__percpu_add_case_8, pcp, val) #define this_cpu_add_2(pcp, val) \ _pcp_protect(__percpu_add_case_16, pcp, val) #define this_cpu_add_4(pcp, val) \ _pcp_protect(__percpu_add_case_32, pcp, val) #define this_cpu_add_8(pcp, val) \ _pcp_protect(__percpu_add_case_64, pcp, val) #define this_cpu_add_return_1(pcp, val) \ _pcp_protect_return(__percpu_add_return_case_8, pcp, val) #define this_cpu_add_return_2(pcp, val) \ _pcp_protect_return(__percpu_add_return_case_16, pcp, val) #define this_cpu_add_return_4(pcp, val) \ _pcp_protect_return(__percpu_add_return_case_32, pcp, val) #define this_cpu_add_return_8(pcp, val) \ _pcp_protect_return(__percpu_add_return_case_64, pcp, val) #define this_cpu_and_1(pcp, val) \ _pcp_protect(__percpu_andnot_case_8, pcp, ~val) #define this_cpu_and_2(pcp, val) \ _pcp_protect(__percpu_andnot_case_16, pcp, ~val) #define this_cpu_and_4(pcp, val) \ _pcp_protect(__percpu_andnot_case_32, pcp, ~val) #define this_cpu_and_8(pcp, val) \ _pcp_protect(__percpu_andnot_case_64, pcp, ~val) #define this_cpu_or_1(pcp, val) \ _pcp_protect(__percpu_or_case_8, pcp, val) #define this_cpu_or_2(pcp, val) \ _pcp_protect(__percpu_or_case_16, pcp, val) #define this_cpu_or_4(pcp, val) \ _pcp_protect(__percpu_or_case_32, pcp, val) #define this_cpu_or_8(pcp, val) \ _pcp_protect(__percpu_or_case_64, pcp, val) #define this_cpu_xchg_1(pcp, val) \ _pcp_protect_return(xchg_relaxed, pcp, val) #define this_cpu_xchg_2(pcp, val) \ _pcp_protect_return(xchg_relaxed, pcp, val) #define this_cpu_xchg_4(pcp, val) \ _pcp_protect_return(xchg_relaxed, pcp, val) #define this_cpu_xchg_8(pcp, val) \ _pcp_protect_return(xchg_relaxed, pcp, val) #define this_cpu_cmpxchg_1(pcp, o, n) \ _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) #define this_cpu_cmpxchg_2(pcp, o, n) \ _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) #define this_cpu_cmpxchg_4(pcp, o, n) \ _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) #define this_cpu_cmpxchg_8(pcp, o, n) \ _pcp_protect_return(cmpxchg_relaxed, pcp, o, n) #define this_cpu_cmpxchg64(pcp, o, n) this_cpu_cmpxchg_8(pcp, o, n) #define this_cpu_cmpxchg128(pcp, o, n) \ ({ \ typedef typeof(pcp) pcp_op_T__; \ u128 old__, new__, ret__; \ pcp_op_T__ *ptr__; \ old__ = o; \ new__ = n; \ preempt_disable_notrace(); \ ptr__ = raw_cpu_ptr(&(pcp)); \ ret__ = cmpxchg128_local((void *)ptr__, old__, new__); \ preempt_enable_notrace(); \ ret__; \ }) #ifdef __KVM_NVHE_HYPERVISOR__ extern unsigned long __hyp_per_cpu_offset(unsigned int cpu); #define __per_cpu_offset #define per_cpu_offset(cpu) __hyp_per_cpu_offset((cpu)) #endif #include /* Redefine macros for nVHE hyp under DEBUG_PREEMPT to avoid its dependencies. */ #if defined(__KVM_NVHE_HYPERVISOR__) && defined(CONFIG_DEBUG_PREEMPT) #undef this_cpu_ptr #define this_cpu_ptr raw_cpu_ptr #undef __this_cpu_read #define __this_cpu_read raw_cpu_read #undef __this_cpu_write #define __this_cpu_write raw_cpu_write #endif #endif /* __ASM_PERCPU_H */