xref: /openbmc/linux/arch/s390/include/asm/percpu.h (revision d2ba09c1)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ARCH_S390_PERCPU__
3 #define __ARCH_S390_PERCPU__
4 
5 #include <linux/preempt.h>
6 #include <asm/cmpxchg.h>
7 
8 /*
9  * s390 uses its own implementation for per cpu data, the offset of
10  * the cpu local data area is cached in the cpu's lowcore memory.
11  */
12 #define __my_cpu_offset S390_lowcore.percpu_offset
13 
14 /*
15  * For 64 bit module code, the module may be more than 4G above the
16  * per cpu area, use weak definitions to force the compiler to
17  * generate external references.
18  */
19 #if defined(CONFIG_SMP) && defined(MODULE)
20 #define ARCH_NEEDS_WEAK_PER_CPU
21 #endif
22 
23 /*
24  * We use a compare-and-swap loop since that uses less cpu cycles than
25  * disabling and enabling interrupts like the generic variant would do.
26  */
27 #define arch_this_cpu_to_op_simple(pcp, val, op)			\
28 ({									\
29 	typedef typeof(pcp) pcp_op_T__;					\
30 	pcp_op_T__ old__, new__, prev__;				\
31 	pcp_op_T__ *ptr__;						\
32 	preempt_disable();						\
33 	ptr__ = raw_cpu_ptr(&(pcp));					\
34 	prev__ = *ptr__;						\
35 	do {								\
36 		old__ = prev__;						\
37 		new__ = old__ op (val);					\
38 		prev__ = cmpxchg(ptr__, old__, new__);			\
39 	} while (prev__ != old__);					\
40 	preempt_enable();						\
41 	new__;								\
42 })
43 
44 #define this_cpu_add_1(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, +)
45 #define this_cpu_add_2(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, +)
46 #define this_cpu_add_return_1(pcp, val) arch_this_cpu_to_op_simple(pcp, val, +)
47 #define this_cpu_add_return_2(pcp, val) arch_this_cpu_to_op_simple(pcp, val, +)
48 #define this_cpu_and_1(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, &)
49 #define this_cpu_and_2(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, &)
50 #define this_cpu_or_1(pcp, val)		arch_this_cpu_to_op_simple(pcp, val, |)
51 #define this_cpu_or_2(pcp, val)		arch_this_cpu_to_op_simple(pcp, val, |)
52 
53 #ifndef CONFIG_HAVE_MARCH_Z196_FEATURES
54 
55 #define this_cpu_add_4(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, +)
56 #define this_cpu_add_8(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, +)
57 #define this_cpu_add_return_4(pcp, val) arch_this_cpu_to_op_simple(pcp, val, +)
58 #define this_cpu_add_return_8(pcp, val) arch_this_cpu_to_op_simple(pcp, val, +)
59 #define this_cpu_and_4(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, &)
60 #define this_cpu_and_8(pcp, val)	arch_this_cpu_to_op_simple(pcp, val, &)
61 #define this_cpu_or_4(pcp, val)		arch_this_cpu_to_op_simple(pcp, val, |)
62 #define this_cpu_or_8(pcp, val)		arch_this_cpu_to_op_simple(pcp, val, |)
63 
64 #else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
65 
66 #define arch_this_cpu_add(pcp, val, op1, op2, szcast)			\
67 {									\
68 	typedef typeof(pcp) pcp_op_T__; 				\
69 	pcp_op_T__ val__ = (val);					\
70 	pcp_op_T__ old__, *ptr__;					\
71 	preempt_disable();						\
72 	ptr__ = raw_cpu_ptr(&(pcp)); 				\
73 	if (__builtin_constant_p(val__) &&				\
74 	    ((szcast)val__ > -129) && ((szcast)val__ < 128)) {		\
75 		asm volatile(						\
76 			op2 "   %[ptr__],%[val__]\n"			\
77 			: [ptr__] "+Q" (*ptr__) 			\
78 			: [val__] "i" ((szcast)val__)			\
79 			: "cc");					\
80 	} else {							\
81 		asm volatile(						\
82 			op1 "   %[old__],%[val__],%[ptr__]\n"		\
83 			: [old__] "=d" (old__), [ptr__] "+Q" (*ptr__)	\
84 			: [val__] "d" (val__)				\
85 			: "cc");					\
86 	}								\
87 	preempt_enable();						\
88 }
89 
90 #define this_cpu_add_4(pcp, val) arch_this_cpu_add(pcp, val, "laa", "asi", int)
91 #define this_cpu_add_8(pcp, val) arch_this_cpu_add(pcp, val, "laag", "agsi", long)
92 
93 #define arch_this_cpu_add_return(pcp, val, op)				\
94 ({									\
95 	typedef typeof(pcp) pcp_op_T__; 				\
96 	pcp_op_T__ val__ = (val);					\
97 	pcp_op_T__ old__, *ptr__;					\
98 	preempt_disable();						\
99 	ptr__ = raw_cpu_ptr(&(pcp));	 				\
100 	asm volatile(							\
101 		op "    %[old__],%[val__],%[ptr__]\n"			\
102 		: [old__] "=d" (old__), [ptr__] "+Q" (*ptr__)		\
103 		: [val__] "d" (val__)					\
104 		: "cc");						\
105 	preempt_enable();						\
106 	old__ + val__;							\
107 })
108 
109 #define this_cpu_add_return_4(pcp, val) arch_this_cpu_add_return(pcp, val, "laa")
110 #define this_cpu_add_return_8(pcp, val) arch_this_cpu_add_return(pcp, val, "laag")
111 
112 #define arch_this_cpu_to_op(pcp, val, op)				\
113 {									\
114 	typedef typeof(pcp) pcp_op_T__; 				\
115 	pcp_op_T__ val__ = (val);					\
116 	pcp_op_T__ old__, *ptr__;					\
117 	preempt_disable();						\
118 	ptr__ = raw_cpu_ptr(&(pcp));	 				\
119 	asm volatile(							\
120 		op "    %[old__],%[val__],%[ptr__]\n"			\
121 		: [old__] "=d" (old__), [ptr__] "+Q" (*ptr__)		\
122 		: [val__] "d" (val__)					\
123 		: "cc");						\
124 	preempt_enable();						\
125 }
126 
127 #define this_cpu_and_4(pcp, val)	arch_this_cpu_to_op(pcp, val, "lan")
128 #define this_cpu_and_8(pcp, val)	arch_this_cpu_to_op(pcp, val, "lang")
129 #define this_cpu_or_4(pcp, val)		arch_this_cpu_to_op(pcp, val, "lao")
130 #define this_cpu_or_8(pcp, val)		arch_this_cpu_to_op(pcp, val, "laog")
131 
132 #endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
133 
134 #define arch_this_cpu_cmpxchg(pcp, oval, nval)				\
135 ({									\
136 	typedef typeof(pcp) pcp_op_T__;					\
137 	pcp_op_T__ ret__;						\
138 	pcp_op_T__ *ptr__;						\
139 	preempt_disable();						\
140 	ptr__ = raw_cpu_ptr(&(pcp));					\
141 	ret__ = cmpxchg(ptr__, oval, nval);				\
142 	preempt_enable();						\
143 	ret__;								\
144 })
145 
146 #define this_cpu_cmpxchg_1(pcp, oval, nval) arch_this_cpu_cmpxchg(pcp, oval, nval)
147 #define this_cpu_cmpxchg_2(pcp, oval, nval) arch_this_cpu_cmpxchg(pcp, oval, nval)
148 #define this_cpu_cmpxchg_4(pcp, oval, nval) arch_this_cpu_cmpxchg(pcp, oval, nval)
149 #define this_cpu_cmpxchg_8(pcp, oval, nval) arch_this_cpu_cmpxchg(pcp, oval, nval)
150 
151 #define arch_this_cpu_xchg(pcp, nval)					\
152 ({									\
153 	typeof(pcp) *ptr__;						\
154 	typeof(pcp) ret__;						\
155 	preempt_disable();						\
156 	ptr__ = raw_cpu_ptr(&(pcp));					\
157 	ret__ = xchg(ptr__, nval);					\
158 	preempt_enable();						\
159 	ret__;								\
160 })
161 
162 #define this_cpu_xchg_1(pcp, nval) arch_this_cpu_xchg(pcp, nval)
163 #define this_cpu_xchg_2(pcp, nval) arch_this_cpu_xchg(pcp, nval)
164 #define this_cpu_xchg_4(pcp, nval) arch_this_cpu_xchg(pcp, nval)
165 #define this_cpu_xchg_8(pcp, nval) arch_this_cpu_xchg(pcp, nval)
166 
167 #define arch_this_cpu_cmpxchg_double(pcp1, pcp2, o1, o2, n1, n2)	\
168 ({									\
169 	typeof(pcp1) o1__ = (o1), n1__ = (n1);				\
170 	typeof(pcp2) o2__ = (o2), n2__ = (n2);				\
171 	typeof(pcp1) *p1__;						\
172 	typeof(pcp2) *p2__;						\
173 	int ret__;							\
174 	preempt_disable();						\
175 	p1__ = raw_cpu_ptr(&(pcp1));					\
176 	p2__ = raw_cpu_ptr(&(pcp2));					\
177 	ret__ = __cmpxchg_double(p1__, p2__, o1__, o2__, n1__, n2__);	\
178 	preempt_enable();						\
179 	ret__;								\
180 })
181 
182 #define this_cpu_cmpxchg_double_8 arch_this_cpu_cmpxchg_double
183 
184 #include <asm-generic/percpu.h>
185 
186 #endif /* __ARCH_S390_PERCPU__ */
187