[S390] s390: move machine flags to lowcore
Currently the storage of the machine flags is a globally exported unsigned
long long variable. By moving the storage location into the lowcore struct we
allow assembler code to check machine_flags directly even without needing a
register. Addtionally the lowcore and therefore the machine flags too will be
in cache most of the time.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/early.c b/arch/s390/kernel/early.c
index 4d221c8..d4e1e5b 100644
--- a/arch/s390/kernel/early.c
+++ b/arch/s390/kernel/early.c
@@ -34,6 +34,8 @@
char kernel_nss_name[NSS_NAME_SIZE + 1];
+static unsigned long machine_flags;
+
static void __init setup_boot_command_line(void);
@@ -391,5 +393,6 @@
setup_hpage();
sclp_facilities_detect();
detect_memory_layout(memory_chunk);
+ S390_lowcore.machine_flags = machine_flags;
lockdep_on();
}
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 06201b9..163bdfe 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -82,9 +82,6 @@
unsigned int console_irq = -1;
EXPORT_SYMBOL(console_irq);
-unsigned long machine_flags;
-EXPORT_SYMBOL(machine_flags);
-
unsigned long elf_hwcap = 0;
char elf_platform[ELF_PLATFORM_SIZE];
@@ -426,6 +423,7 @@
__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
lc->current_task = (unsigned long) init_thread_union.thread_info.task;
lc->thread_info = (unsigned long) &init_thread_union;
+ lc->machine_flags = S390_lowcore.machine_flags;
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE) {
lc->extended_save_area_addr = (__u32)
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 006ed50..7966302 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -571,6 +571,7 @@
cpu_lowcore->current_task = (unsigned long) idle;
cpu_lowcore->cpu_nr = cpu;
cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
+ cpu_lowcore->machine_flags = S390_lowcore.machine_flags;
eieio();
while (signal_processor(cpu, sigp_restart) == sigp_busy)