s390: query dynamic DEBUG_PAGEALLOC setting

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>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 6 deletions

diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index ef7d6c8fea66..d27fccbad7c1 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)