aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/lib
diff options
context:
space:
mode:
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2012-03-11 11:59:26 -0400
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2012-03-11 11:59:28 -0400
commit8b646bd759086f6090fe27acf414c0b5faa737f4 (patch)
tree29475659031c57ccf2ca43899614ab5c6b1899a0 /arch/s390/lib
parent7e180bd8020d213bb0de15c3606968f8a9262439 (diff)
[S390] rework smp code
Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/lib')
-rw-r--r--arch/s390/lib/spinlock.c30
1 files changed, 8 insertions, 22 deletions
diff --git a/arch/s390/lib/spinlock.c b/arch/s390/lib/spinlock.c
index 91754ffb9203..093eb694d9c1 100644
--- a/arch/s390/lib/spinlock.c
+++ b/arch/s390/lib/spinlock.c
@@ -10,6 +10,7 @@
10#include <linux/module.h> 10#include <linux/module.h>
11#include <linux/spinlock.h> 11#include <linux/spinlock.h>
12#include <linux/init.h> 12#include <linux/init.h>
13#include <linux/smp.h>
13#include <asm/io.h> 14#include <asm/io.h>
14 15
15int spin_retry = 1000; 16int spin_retry = 1000;
@@ -24,21 +25,6 @@ static int __init spin_retry_setup(char *str)
24} 25}
25__setup("spin_retry=", spin_retry_setup); 26__setup("spin_retry=", spin_retry_setup);
26 27
27static inline void _raw_yield(void)
28{
29 if (MACHINE_HAS_DIAG44)
30 asm volatile("diag 0,0,0x44");
31}
32
33static inline void _raw_yield_cpu(int cpu)
34{
35 if (MACHINE_HAS_DIAG9C)
36 asm volatile("diag %0,0,0x9c"
37 : : "d" (cpu_logical_map(cpu)));
38 else
39 _raw_yield();
40}
41
42void arch_spin_lock_wait(arch_spinlock_t *lp) 28void arch_spin_lock_wait(arch_spinlock_t *lp)
43{ 29{
44 int count = spin_retry; 30 int count = spin_retry;
@@ -60,7 +46,7 @@ void arch_spin_lock_wait(arch_spinlock_t *lp)
60 } 46 }
61 owner = lp->owner_cpu; 47 owner = lp->owner_cpu;
62 if (owner) 48 if (owner)
63 _raw_yield_cpu(~owner); 49 smp_yield_cpu(~owner);
64 if (_raw_compare_and_swap(&lp->owner_cpu, 0, cpu) == 0) 50 if (_raw_compare_and_swap(&lp->owner_cpu, 0, cpu) == 0)
65 return; 51 return;
66 } 52 }
@@ -91,7 +77,7 @@ void arch_spin_lock_wait_flags(arch_spinlock_t *lp, unsigned long flags)
91 } 77 }
92 owner = lp->owner_cpu; 78 owner = lp->owner_cpu;
93 if (owner) 79 if (owner)
94 _raw_yield_cpu(~owner); 80 smp_yield_cpu(~owner);
95 local_irq_disable(); 81 local_irq_disable();
96 if (_raw_compare_and_swap(&lp->owner_cpu, 0, cpu) == 0) 82 if (_raw_compare_and_swap(&lp->owner_cpu, 0, cpu) == 0)
97 return; 83 return;
@@ -121,7 +107,7 @@ void arch_spin_relax(arch_spinlock_t *lock)
121 if (cpu != 0) { 107 if (cpu != 0) {
122 if (MACHINE_IS_VM || MACHINE_IS_KVM || 108 if (MACHINE_IS_VM || MACHINE_IS_KVM ||
123 !smp_vcpu_scheduled(~cpu)) 109 !smp_vcpu_scheduled(~cpu))
124 _raw_yield_cpu(~cpu); 110 smp_yield_cpu(~cpu);
125 } 111 }
126} 112}
127EXPORT_SYMBOL(arch_spin_relax); 113EXPORT_SYMBOL(arch_spin_relax);
@@ -133,7 +119,7 @@ void _raw_read_lock_wait(arch_rwlock_t *rw)
133 119
134 while (1) { 120 while (1) {
135 if (count-- <= 0) { 121 if (count-- <= 0) {
136 _raw_yield(); 122 smp_yield();
137 count = spin_retry; 123 count = spin_retry;
138 } 124 }
139 if (!arch_read_can_lock(rw)) 125 if (!arch_read_can_lock(rw))
@@ -153,7 +139,7 @@ void _raw_read_lock_wait_flags(arch_rwlock_t *rw, unsigned long flags)
153 local_irq_restore(flags); 139 local_irq_restore(flags);
154 while (1) { 140 while (1) {
155 if (count-- <= 0) { 141 if (count-- <= 0) {
156 _raw_yield(); 142 smp_yield();
157 count = spin_retry; 143 count = spin_retry;
158 } 144 }
159 if (!arch_read_can_lock(rw)) 145 if (!arch_read_can_lock(rw))
@@ -188,7 +174,7 @@ void _raw_write_lock_wait(arch_rwlock_t *rw)
188 174
189 while (1) { 175 while (1) {
190 if (count-- <= 0) { 176 if (count-- <= 0) {
191 _raw_yield(); 177 smp_yield();
192 count = spin_retry; 178 count = spin_retry;
193 } 179 }
194 if (!arch_write_can_lock(rw)) 180 if (!arch_write_can_lock(rw))
@@ -206,7 +192,7 @@ void _raw_write_lock_wait_flags(arch_rwlock_t *rw, unsigned long flags)
206 local_irq_restore(flags); 192 local_irq_restore(flags);
207 while (1) { 193 while (1) {
208 if (count-- <= 0) { 194 if (count-- <= 0) {
209 _raw_yield(); 195 smp_yield();
210 count = spin_retry; 196 count = spin_retry;
211 } 197 }
212 if (!arch_write_can_lock(rw)) 198 if (!arch_write_can_lock(rw))