[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, 7 insertions, 21 deletions

diff --git a/arch/s390/kernel/vdso.c b/arch/s390/kernel/vdso.c
index d73630b4fe1d..e704a9965f90 100644
--- a/arch/s390/kernel/vdso.c
+++ b/arch/s390/kernel/vdso.c
@@ -89,18 +89,11 @@ static void vdso_init_data(struct vdso_data *vd)
 
 #ifdef CONFIG_64BIT
 /*
- * Setup per cpu vdso data page.
- */
-static void vdso_init_per_cpu_data(int cpu, struct vdso_per_cpu_data *vpcd)
-{
-}
-
-/*
  * Allocate/free per cpu vdso data.
  */
 #define SEGMENT_ORDER	2
 
-int vdso_alloc_per_cpu(int cpu, struct _lowcore *lowcore)
+int vdso_alloc_per_cpu(struct _lowcore *lowcore)
 {
 	unsigned long segment_table, page_table, page_frame;
 	u32 *psal, *aste;
@@ -139,7 +132,6 @@ int vdso_alloc_per_cpu(int cpu, struct _lowcore *lowcore)
 	aste[4] = (u32)(addr_t) psal;
 	lowcore->vdso_per_cpu_data = page_frame;
 
-	vdso_init_per_cpu_data(cpu, (struct vdso_per_cpu_data *) page_frame);
 	return 0;
 
 out:
@@ -149,7 +141,7 @@ out:
 	return -ENOMEM;
 }
 
-void vdso_free_per_cpu(int cpu, struct _lowcore *lowcore)
+void vdso_free_per_cpu(struct _lowcore *lowcore)
 {
 	unsigned long segment_table, page_table, page_frame;
 	u32 *psal, *aste;
@@ -168,19 +160,15 @@ void vdso_free_per_cpu(int cpu, struct _lowcore *lowcore)
 	free_pages(segment_table, SEGMENT_ORDER);
 }
 
-static void __vdso_init_cr5(void *dummy)
+static void vdso_init_cr5(void)
 {
 	unsigned long cr5;
 
+	if (user_mode == HOME_SPACE_MODE || !vdso_enabled)
+		return;
 	cr5 = offsetof(struct _lowcore, paste);
 	__ctl_load(cr5, 5, 5);
 }
-
-static void vdso_init_cr5(void)
-{
-	if (user_mode != HOME_SPACE_MODE && vdso_enabled)
-		on_each_cpu(__vdso_init_cr5, NULL, 1);
-}
 #endif /* CONFIG_64BIT */
 
 /*
@@ -322,10 +310,8 @@ static int __init vdso_init(void)
 	}
 	vdso64_pagelist[vdso64_pages - 1] = virt_to_page(vdso_data);
 	vdso64_pagelist[vdso64_pages] = NULL;
-#ifndef CONFIG_SMP
-	if (vdso_alloc_per_cpu(0, &S390_lowcore))
+	if (vdso_alloc_per_cpu(&S390_lowcore))
 		BUG();
-#endif
 	vdso_init_cr5();
 #endif /* CONFIG_64BIT */
 
@@ -335,7 +321,7 @@ static int __init vdso_init(void)
 
 	return 0;
 }
-arch_initcall(vdso_init);
+early_initcall(vdso_init);
 
 int in_gate_area_no_mm(unsigned long addr)
 {