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-rw-r--r--arch/arm64/include/asm/percpu.h311
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diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h
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+/*
+ * Copyright (C) 2013 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PERCPU_H
+#define __ASM_PERCPU_H
+
+#include <linux/preempt.h>
+
+#include <asm/alternative.h>
+#include <asm/cmpxchg.h>
+#include <asm/stack_pointer.h>
+
+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 __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;
+}
+#define __my_cpu_offset __my_cpu_offset()
+
+#define PERCPU_OP(op, asm_op) \
+static inline unsigned long __percpu_##op(void *ptr, \
+ unsigned long val, int size) \
+{ \
+ unsigned long loop, ret; \
+ \
+ switch (size) { \
+ case 1: \
+ asm ("//__per_cpu_" #op "_1\n" \
+ "1: ldxrb %w[ret], %[ptr]\n" \
+ #asm_op " %w[ret], %w[ret], %w[val]\n" \
+ " stxrb %w[loop], %w[ret], %[ptr]\n" \
+ " cbnz %w[loop], 1b" \
+ : [loop] "=&r" (loop), [ret] "=&r" (ret), \
+ [ptr] "+Q"(*(u8 *)ptr) \
+ : [val] "Ir" (val)); \
+ break; \
+ case 2: \
+ asm ("//__per_cpu_" #op "_2\n" \
+ "1: ldxrh %w[ret], %[ptr]\n" \
+ #asm_op " %w[ret], %w[ret], %w[val]\n" \
+ " stxrh %w[loop], %w[ret], %[ptr]\n" \
+ " cbnz %w[loop], 1b" \
+ : [loop] "=&r" (loop), [ret] "=&r" (ret), \
+ [ptr] "+Q"(*(u16 *)ptr) \
+ : [val] "Ir" (val)); \
+ break; \
+ case 4: \
+ asm ("//__per_cpu_" #op "_4\n" \
+ "1: ldxr %w[ret], %[ptr]\n" \
+ #asm_op " %w[ret], %w[ret], %w[val]\n" \
+ " stxr %w[loop], %w[ret], %[ptr]\n" \
+ " cbnz %w[loop], 1b" \
+ : [loop] "=&r" (loop), [ret] "=&r" (ret), \
+ [ptr] "+Q"(*(u32 *)ptr) \
+ : [val] "Ir" (val)); \
+ break; \
+ case 8: \
+ asm ("//__per_cpu_" #op "_8\n" \
+ "1: ldxr %[ret], %[ptr]\n" \
+ #asm_op " %[ret], %[ret], %[val]\n" \
+ " stxr %w[loop], %[ret], %[ptr]\n" \
+ " cbnz %w[loop], 1b" \
+ : [loop] "=&r" (loop), [ret] "=&r" (ret), \
+ [ptr] "+Q"(*(u64 *)ptr) \
+ : [val] "Ir" (val)); \
+ break; \
+ default: \
+ ret = 0; \
+ BUILD_BUG(); \
+ } \
+ \
+ return ret; \
+}
+
+PERCPU_OP(add, add)
+PERCPU_OP(and, and)
+PERCPU_OP(or, orr)
+#undef PERCPU_OP
+
+static inline unsigned long __percpu_read(void *ptr, int size)
+{
+ unsigned long ret;
+
+ switch (size) {
+ case 1:
+ ret = READ_ONCE(*(u8 *)ptr);
+ break;
+ case 2:
+ ret = READ_ONCE(*(u16 *)ptr);
+ break;
+ case 4:
+ ret = READ_ONCE(*(u32 *)ptr);
+ break;
+ case 8:
+ ret = READ_ONCE(*(u64 *)ptr);
+ break;
+ default:
+ ret = 0;
+ BUILD_BUG();
+ }
+
+ return ret;
+}
+
+static inline void __percpu_write(void *ptr, unsigned long val, int size)
+{
+ switch (size) {
+ case 1:
+ WRITE_ONCE(*(u8 *)ptr, (u8)val);
+ break;
+ case 2:
+ WRITE_ONCE(*(u16 *)ptr, (u16)val);
+ break;
+ case 4:
+ WRITE_ONCE(*(u32 *)ptr, (u32)val);
+ break;
+ case 8:
+ WRITE_ONCE(*(u64 *)ptr, (u64)val);
+ break;
+ default:
+ BUILD_BUG();
+ }
+}
+
+static inline unsigned long __percpu_xchg(void *ptr, unsigned long val,
+ int size)
+{
+ unsigned long ret, loop;
+
+ switch (size) {
+ case 1:
+ asm ("//__percpu_xchg_1\n"
+ "1: ldxrb %w[ret], %[ptr]\n"
+ " stxrb %w[loop], %w[val], %[ptr]\n"
+ " cbnz %w[loop], 1b"
+ : [loop] "=&r"(loop), [ret] "=&r"(ret),
+ [ptr] "+Q"(*(u8 *)ptr)
+ : [val] "r" (val));
+ break;
+ case 2:
+ asm ("//__percpu_xchg_2\n"
+ "1: ldxrh %w[ret], %[ptr]\n"
+ " stxrh %w[loop], %w[val], %[ptr]\n"
+ " cbnz %w[loop], 1b"
+ : [loop] "=&r"(loop), [ret] "=&r"(ret),
+ [ptr] "+Q"(*(u16 *)ptr)
+ : [val] "r" (val));
+ break;
+ case 4:
+ asm ("//__percpu_xchg_4\n"
+ "1: ldxr %w[ret], %[ptr]\n"
+ " stxr %w[loop], %w[val], %[ptr]\n"
+ " cbnz %w[loop], 1b"
+ : [loop] "=&r"(loop), [ret] "=&r"(ret),
+ [ptr] "+Q"(*(u32 *)ptr)
+ : [val] "r" (val));
+ break;
+ case 8:
+ asm ("//__percpu_xchg_8\n"
+ "1: ldxr %[ret], %[ptr]\n"
+ " stxr %w[loop], %[val], %[ptr]\n"
+ " cbnz %w[loop], 1b"
+ : [loop] "=&r"(loop), [ret] "=&r"(ret),
+ [ptr] "+Q"(*(u64 *)ptr)
+ : [val] "r" (val));
+ break;
+ default:
+ ret = 0;
+ BUILD_BUG();
+ }
+
+ return ret;
+}
+
+/* this_cpu_cmpxchg */
+#define _protect_cmpxchg_local(pcp, o, n) \
+({ \
+ typeof(*raw_cpu_ptr(&(pcp))) __ret; \
+ preempt_disable(); \
+ __ret = cmpxchg_local(raw_cpu_ptr(&(pcp)), o, n); \
+ preempt_enable(); \
+ __ret; \
+})
+
+#define this_cpu_cmpxchg_1(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
+#define this_cpu_cmpxchg_2(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
+#define this_cpu_cmpxchg_4(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
+#define this_cpu_cmpxchg_8(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
+
+#define this_cpu_cmpxchg_double_8(ptr1, ptr2, o1, o2, n1, n2) \
+({ \
+ int __ret; \
+ preempt_disable(); \
+ __ret = cmpxchg_double_local( raw_cpu_ptr(&(ptr1)), \
+ raw_cpu_ptr(&(ptr2)), \
+ o1, o2, n1, n2); \
+ preempt_enable(); \
+ __ret; \
+})
+
+#define _percpu_read(pcp) \
+({ \
+ typeof(pcp) __retval; \
+ preempt_disable_notrace(); \
+ __retval = (typeof(pcp))__percpu_read(raw_cpu_ptr(&(pcp)), \
+ sizeof(pcp)); \
+ preempt_enable_notrace(); \
+ __retval; \
+})
+
+#define _percpu_write(pcp, val) \
+do { \
+ preempt_disable_notrace(); \
+ __percpu_write(raw_cpu_ptr(&(pcp)), (unsigned long)(val), \
+ sizeof(pcp)); \
+ preempt_enable_notrace(); \
+} while(0) \
+
+#define _pcp_protect(operation, pcp, val) \
+({ \
+ typeof(pcp) __retval; \
+ preempt_disable(); \
+ __retval = (typeof(pcp))operation(raw_cpu_ptr(&(pcp)), \
+ (val), sizeof(pcp)); \
+ preempt_enable(); \
+ __retval; \
+})
+
+#define _percpu_add(pcp, val) \
+ _pcp_protect(__percpu_add, pcp, val)
+
+#define _percpu_add_return(pcp, val) _percpu_add(pcp, val)
+
+#define _percpu_and(pcp, val) \
+ _pcp_protect(__percpu_and, pcp, val)
+
+#define _percpu_or(pcp, val) \
+ _pcp_protect(__percpu_or, pcp, val)
+
+#define _percpu_xchg(pcp, val) (typeof(pcp)) \
+ _pcp_protect(__percpu_xchg, pcp, (unsigned long)(val))
+
+#define this_cpu_add_1(pcp, val) _percpu_add(pcp, val)
+#define this_cpu_add_2(pcp, val) _percpu_add(pcp, val)
+#define this_cpu_add_4(pcp, val) _percpu_add(pcp, val)
+#define this_cpu_add_8(pcp, val) _percpu_add(pcp, val)
+
+#define this_cpu_add_return_1(pcp, val) _percpu_add_return(pcp, val)
+#define this_cpu_add_return_2(pcp, val) _percpu_add_return(pcp, val)
+#define this_cpu_add_return_4(pcp, val) _percpu_add_return(pcp, val)
+#define this_cpu_add_return_8(pcp, val) _percpu_add_return(pcp, val)
+
+#define this_cpu_and_1(pcp, val) _percpu_and(pcp, val)
+#define this_cpu_and_2(pcp, val) _percpu_and(pcp, val)
+#define this_cpu_and_4(pcp, val) _percpu_and(pcp, val)
+#define this_cpu_and_8(pcp, val) _percpu_and(pcp, val)
+
+#define this_cpu_or_1(pcp, val) _percpu_or(pcp, val)
+#define this_cpu_or_2(pcp, val) _percpu_or(pcp, val)
+#define this_cpu_or_4(pcp, val) _percpu_or(pcp, val)
+#define this_cpu_or_8(pcp, val) _percpu_or(pcp, val)
+
+#define this_cpu_read_1(pcp) _percpu_read(pcp)
+#define this_cpu_read_2(pcp) _percpu_read(pcp)
+#define this_cpu_read_4(pcp) _percpu_read(pcp)
+#define this_cpu_read_8(pcp) _percpu_read(pcp)
+
+#define this_cpu_write_1(pcp, val) _percpu_write(pcp, val)
+#define this_cpu_write_2(pcp, val) _percpu_write(pcp, val)
+#define this_cpu_write_4(pcp, val) _percpu_write(pcp, val)
+#define this_cpu_write_8(pcp, val) _percpu_write(pcp, val)
+
+#define this_cpu_xchg_1(pcp, val) _percpu_xchg(pcp, val)
+#define this_cpu_xchg_2(pcp, val) _percpu_xchg(pcp, val)
+#define this_cpu_xchg_4(pcp, val) _percpu_xchg(pcp, val)
+#define this_cpu_xchg_8(pcp, val) _percpu_xchg(pcp, val)
+
+#include <asm-generic/percpu.h>
+
+#endif /* __ASM_PERCPU_H */