[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>

1 files changed, 8 insertions, 1 deletions

diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h
index bf538aaf407d..92b1617d0c95 100644
--- a/arch/s390/kernel/entry.h
+++ b/arch/s390/kernel/entry.h
@@ -9,6 +9,14 @@
 extern void (*pgm_check_table[128])(struct pt_regs *);
 extern void *restart_stack;
 
+void system_call(void);
+void pgm_check_handler(void);
+void ext_int_handler(void);
+void io_int_handler(void);
+void mcck_int_handler(void);
+void restart_int_handler(void);
+void restart_call_handler(void);
+
 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs);
 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs);
 
@@ -26,7 +34,6 @@ void do_notify_resume(struct pt_regs *regs);
 
 void do_extint(struct pt_regs *regs, unsigned int, unsigned int, unsigned long);
 void do_restart(void);
-int __cpuinit start_secondary(void *cpuvoid);
 void __init startup_init(void);
 void die(struct pt_regs *regs, const char *str);