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-rw-r--r--arch/um/drivers/mconsole_kern.c1
-rw-r--r--arch/um/include/asm/Kbuild2
-rw-r--r--arch/x86/um/asm/barrier.h75
-rw-r--r--arch/x86/um/asm/switch_to.h7
-rw-r--r--arch/x86/um/asm/system.h135
5 files changed, 84 insertions, 136 deletions
diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index e672bd6d43e3..43b39d61b538 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -22,6 +22,7 @@
22#include <linux/workqueue.h> 22#include <linux/workqueue.h>
23#include <linux/mutex.h> 23#include <linux/mutex.h>
24#include <asm/uaccess.h> 24#include <asm/uaccess.h>
25#include <asm/switch_to.h>
25 26
26#include "init.h" 27#include "init.h"
27#include "irq_kern.h" 28#include "irq_kern.h"
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild
index 8419f5cf2ac7..bb5d6e68829b 100644
--- a/arch/um/include/asm/Kbuild
+++ b/arch/um/include/asm/Kbuild
@@ -1,3 +1,3 @@
1generic-y += bug.h cputime.h device.h emergency-restart.h futex.h hardirq.h 1generic-y += bug.h cputime.h device.h emergency-restart.h futex.h hardirq.h
2generic-y += hw_irq.h irq_regs.h kdebug.h percpu.h sections.h topology.h xor.h 2generic-y += hw_irq.h irq_regs.h kdebug.h percpu.h sections.h topology.h xor.h
3generic-y += ftrace.h pci.h io.h param.h delay.h mutex.h current.h 3generic-y += ftrace.h pci.h io.h param.h delay.h mutex.h current.h exec.h
diff --git a/arch/x86/um/asm/barrier.h b/arch/x86/um/asm/barrier.h
new file mode 100644
index 000000000000..7d01b8c56c00
--- /dev/null
+++ b/arch/x86/um/asm/barrier.h
@@ -0,0 +1,75 @@
1#ifndef _ASM_UM_BARRIER_H_
2#define _ASM_UM_BARRIER_H_
3
4#include <asm/asm.h>
5#include <asm/segment.h>
6#include <asm/cpufeature.h>
7#include <asm/cmpxchg.h>
8#include <asm/nops.h>
9
10#include <linux/kernel.h>
11#include <linux/irqflags.h>
12
13/*
14 * Force strict CPU ordering.
15 * And yes, this is required on UP too when we're talking
16 * to devices.
17 */
18#ifdef CONFIG_X86_32
19
20#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2)
21#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2)
22#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM)
23
24#else /* CONFIG_X86_32 */
25
26#define mb() asm volatile("mfence" : : : "memory")
27#define rmb() asm volatile("lfence" : : : "memory")
28#define wmb() asm volatile("sfence" : : : "memory")
29
30#endif /* CONFIG_X86_32 */
31
32#define read_barrier_depends() do { } while (0)
33
34#ifdef CONFIG_SMP
35
36#define smp_mb() mb()
37#ifdef CONFIG_X86_PPRO_FENCE
38#define smp_rmb() rmb()
39#else /* CONFIG_X86_PPRO_FENCE */
40#define smp_rmb() barrier()
41#endif /* CONFIG_X86_PPRO_FENCE */
42
43#ifdef CONFIG_X86_OOSTORE
44#define smp_wmb() wmb()
45#else /* CONFIG_X86_OOSTORE */
46#define smp_wmb() barrier()
47#endif /* CONFIG_X86_OOSTORE */
48
49#define smp_read_barrier_depends() read_barrier_depends()
50#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)
51
52#else /* CONFIG_SMP */
53
54#define smp_mb() barrier()
55#define smp_rmb() barrier()
56#define smp_wmb() barrier()
57#define smp_read_barrier_depends() do { } while (0)
58#define set_mb(var, value) do { var = value; barrier(); } while (0)
59
60#endif /* CONFIG_SMP */
61
62/*
63 * Stop RDTSC speculation. This is needed when you need to use RDTSC
64 * (or get_cycles or vread that possibly accesses the TSC) in a defined
65 * code region.
66 *
67 * (Could use an alternative three way for this if there was one.)
68 */
69static inline void rdtsc_barrier(void)
70{
71 alternative(ASM_NOP3, "mfence", X86_FEATURE_MFENCE_RDTSC);
72 alternative(ASM_NOP3, "lfence", X86_FEATURE_LFENCE_RDTSC);
73}
74
75#endif
diff --git a/arch/x86/um/asm/switch_to.h b/arch/x86/um/asm/switch_to.h
new file mode 100644
index 000000000000..cf97d20da61f
--- /dev/null
+++ b/arch/x86/um/asm/switch_to.h
@@ -0,0 +1,7 @@
1#ifndef _ASM_UM_SWITCH_TO_H_
2#define _ASM_UM_SWITCH_TO_H_
3
4extern void *_switch_to(void *prev, void *next, void *last);
5#define switch_to(prev, next, last) prev = _switch_to(prev, next, last)
6
7#endif
diff --git a/arch/x86/um/asm/system.h b/arch/x86/um/asm/system.h
deleted file mode 100644
index a459fd9b7598..000000000000
--- a/arch/x86/um/asm/system.h
+++ /dev/null
@@ -1,135 +0,0 @@
1#ifndef _ASM_X86_SYSTEM_H_
2#define _ASM_X86_SYSTEM_H_
3
4#include <asm/asm.h>
5#include <asm/segment.h>
6#include <asm/cpufeature.h>
7#include <asm/cmpxchg.h>
8#include <asm/nops.h>
9
10#include <linux/kernel.h>
11#include <linux/irqflags.h>
12
13/* entries in ARCH_DLINFO: */
14#ifdef CONFIG_IA32_EMULATION
15# define AT_VECTOR_SIZE_ARCH 2
16#else
17# define AT_VECTOR_SIZE_ARCH 1
18#endif
19
20extern unsigned long arch_align_stack(unsigned long sp);
21
22void default_idle(void);
23
24/*
25 * Force strict CPU ordering.
26 * And yes, this is required on UP too when we're talking
27 * to devices.
28 */
29#ifdef CONFIG_X86_32
30/*
31 * Some non-Intel clones support out of order store. wmb() ceases to be a
32 * nop for these.
33 */
34#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2)
35#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2)
36#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM)
37#else
38#define mb() asm volatile("mfence":::"memory")
39#define rmb() asm volatile("lfence":::"memory")
40#define wmb() asm volatile("sfence" ::: "memory")
41#endif
42
43/**
44 * read_barrier_depends - Flush all pending reads that subsequents reads
45 * depend on.
46 *
47 * No data-dependent reads from memory-like regions are ever reordered
48 * over this barrier. All reads preceding this primitive are guaranteed
49 * to access memory (but not necessarily other CPUs' caches) before any
50 * reads following this primitive that depend on the data return by
51 * any of the preceding reads. This primitive is much lighter weight than
52 * rmb() on most CPUs, and is never heavier weight than is
53 * rmb().
54 *
55 * These ordering constraints are respected by both the local CPU
56 * and the compiler.
57 *
58 * Ordering is not guaranteed by anything other than these primitives,
59 * not even by data dependencies. See the documentation for
60 * memory_barrier() for examples and URLs to more information.
61 *
62 * For example, the following code would force ordering (the initial
63 * value of "a" is zero, "b" is one, and "p" is "&a"):
64 *
65 * <programlisting>
66 * CPU 0 CPU 1
67 *
68 * b = 2;
69 * memory_barrier();
70 * p = &b; q = p;
71 * read_barrier_depends();
72 * d = *q;
73 * </programlisting>
74 *
75 * because the read of "*q" depends on the read of "p" and these
76 * two reads are separated by a read_barrier_depends(). However,
77 * the following code, with the same initial values for "a" and "b":
78 *
79 * <programlisting>
80 * CPU 0 CPU 1
81 *
82 * a = 2;
83 * memory_barrier();
84 * b = 3; y = b;
85 * read_barrier_depends();
86 * x = a;
87 * </programlisting>
88 *
89 * does not enforce ordering, since there is no data dependency between
90 * the read of "a" and the read of "b". Therefore, on some CPUs, such
91 * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb()
92 * in cases like this where there are no data dependencies.
93 **/
94
95#define read_barrier_depends() do { } while (0)
96
97#ifdef CONFIG_SMP
98#define smp_mb() mb()
99#ifdef CONFIG_X86_PPRO_FENCE
100# define smp_rmb() rmb()
101#else
102# define smp_rmb() barrier()
103#endif
104#ifdef CONFIG_X86_OOSTORE
105# define smp_wmb() wmb()
106#else
107# define smp_wmb() barrier()
108#endif
109#define smp_read_barrier_depends() read_barrier_depends()
110#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)
111#else
112#define smp_mb() barrier()
113#define smp_rmb() barrier()
114#define smp_wmb() barrier()
115#define smp_read_barrier_depends() do { } while (0)
116#define set_mb(var, value) do { var = value; barrier(); } while (0)
117#endif
118
119/*
120 * Stop RDTSC speculation. This is needed when you need to use RDTSC
121 * (or get_cycles or vread that possibly accesses the TSC) in a defined
122 * code region.
123 *
124 * (Could use an alternative three way for this if there was one.)
125 */
126static inline void rdtsc_barrier(void)
127{
128 alternative(ASM_NOP3, "mfence", X86_FEATURE_MFENCE_RDTSC);
129 alternative(ASM_NOP3, "lfence", X86_FEATURE_LFENCE_RDTSC);
130}
131
132extern void *_switch_to(void *prev, void *next, void *last);
133#define switch_to(prev, next, last) prev = _switch_to(prev, next, last)
134
135#endif