[PATCH v3 3/3] s390: query dynamic DEBUG_PAGEALLOC setting

Christian Borntraeger
2016-01-27T10:09:54Z

We can use debug_pagealloc_enabled() to check if we can map
the identity mapping with 1MB/2GB pages as well as to print
the current setting in dump_stack.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
---
arch/s390/kernel/dumpstack.c | 6 +++---
arch/s390/mm/vmem.c | 10 ++++------
2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
index dc8e204..e57eb22 100644
--- a/arch/s390/kernel/dumpstack.c
+++ b/arch/s390/kernel/dumpstack.c
@@ -11,6 +11,7 @@
#include <linux/export.h>
#include <linux/kdebug.h>
#include <linux/ptrace.h>
+#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <asm/processor.h>
@@ -185,9 +186,8 @@ void die(struct pt_regs *regs, const char *str)
#ifdef CONFIG_SMP
printk("SMP ");
#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
- printk("DEBUG_PAGEALLOC");
-#endif
+ if (debug_pagealloc_enabled())
+ printk("DEBUG_PAGEALLOC");
printk("\n");
notify_die(DIE_OOPS, str, regs, 0, regs->int_code & 0xffff, SIGSEGV);
print_modules();
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index ef7d6c8..d27fccba 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -94,16 +94,15 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
pgd_populate(&init_mm, pg_dir, pu_dir);
}
pu_dir = pud_offset(pg_dir, address);
-#ifndef CONFIG_DEBUG_PAGEALLOC
if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address &&
- !(address & ~PUD_MASK) && (address + PUD_SIZE <= end)) {
+ !(address & ~PUD_MASK) && (address + PUD_SIZE <= end) &&
+ !debug_pagealloc_enabled()) {
pud_val(*pu_dir) = __pa(address) |
_REGION_ENTRY_TYPE_R3 | _REGION3_ENTRY_LARGE |
(ro ? _REGION_ENTRY_PROTECT : 0);
address += PUD_SIZE;
continue;
}
-#endif
if (pud_none(*pu_dir)) {
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
@@ -111,9 +110,9 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
pud_populate(&init_mm, pu_dir, pm_dir);
}
pm_dir = pmd_offset(pu_dir, address);
-#ifndef CONFIG_DEBUG_PAGEALLOC
if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address &&
- !(address & ~PMD_MASK) && (address + PMD_SIZE <= end)) {
+ !(address & ~PMD_MASK) && (address + PMD_SIZE <= end) &&
+ !debug_pagealloc_enabled()) {
pmd_val(*pm_dir) = __pa(address) |
_SEGMENT_ENTRY | _SEGMENT_ENTRY_LARGE |
_SEGMENT_ENTRY_YOUNG |
@@ -121,7 +120,6 @@ static int vmem_add_mem(unsigned long start, unsigned long size, int ro)
address += PMD_SIZE;
continue;
}
-#endif
if (pmd_none(*pm_dir)) {
pt_dir = vmem_pte_alloc(address);
if (!pt_dir)
--
2.3.0