* [PATCH v2 0/3] Optimize CONFIG_DEBUG_PAGEALLOC
@ 2016-01-27 8:50 ` Christian Borntraeger
0 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
As CONFIG_DEBUG_PAGEALLOC can be enabled/disabled via kernel
parameters we can optimize some cases by checking the enablement
state.
I have done s390 and x86 as examples.
s390 should be ok, I tested several combinations, x86 seems to
work as well, but I have some concerns about the 1GB pages.
The previous code did not bother at all with CONFIG_DEBUG_PAGEALLOC
and I do not fully understand why.
Power can probably do the same, Michael/Ben?
I am not sure about sparc. Sparc seems to allocate the TSB buffer
really early. David?
V1->V2:
- replace DEBUG_PAGEALLOC(disabled/enabled) with DEBUG_PAGEALLOC
dump_stack for s390/x86
- add /* CONFIG_DEBUG_PAGEALLOC */ to else and endif
Christian Borntraeger (3):
mm: provide debug_pagealloc_enabled() without CONFIG_DEBUG_PAGEALLOC
x86: query dynamic DEBUG_PAGEALLOC setting
s390: query dynamic DEBUG_PAGEALLOC setting
arch/s390/kernel/dumpstack.c | 8 ++++----
arch/s390/mm/vmem.c | 10 ++++------
arch/x86/kernel/dumpstack.c | 5 ++---
arch/x86/mm/init.c | 7 ++++---
arch/x86/mm/pageattr.c | 14 ++++----------
include/linux/mm.h | 9 +++++++--
6 files changed, 25 insertions(+), 28 deletions(-)
--
2.3.0
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^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 1/3] mm: provide debug_pagealloc_enabled() without CONFIG_DEBUG_PAGEALLOC
2016-01-27 8:50 ` Christian Borntraeger
@ 2016-01-27 8:50 ` Christian Borntraeger
-1 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
We can provide debug_pagealloc_enabled() also if CONFIG_DEBUG_PAGEALLOC
is not set. It will return false in that case.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
---
include/linux/mm.h | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7783073..56cab4e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2147,13 +2147,18 @@ kernel_map_pages(struct page *page, int numpages, int enable)
#ifdef CONFIG_HIBERNATION
extern bool kernel_page_present(struct page *page);
#endif /* CONFIG_HIBERNATION */
-#else
+#else /* CONFIG_DEBUG_PAGEALLOC */
+static inline bool debug_pagealloc_enabled(void)
+{
+ return false;
+}
+
static inline void
kernel_map_pages(struct page *page, int numpages, int enable) {}
#ifdef CONFIG_HIBERNATION
static inline bool kernel_page_present(struct page *page) { return true; }
#endif /* CONFIG_HIBERNATION */
-#endif
+#endif /* CONFIG_DEBUG_PAGEALLOC */
#ifdef __HAVE_ARCH_GATE_AREA
extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
--
2.3.0
^ permalink raw reply related [flat|nested] 14+ messages in thread* [PATCH v2 1/3] mm: provide debug_pagealloc_enabled() without CONFIG_DEBUG_PAGEALLOC
@ 2016-01-27 8:50 ` Christian Borntraeger
0 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
We can provide debug_pagealloc_enabled() also if CONFIG_DEBUG_PAGEALLOC
is not set. It will return false in that case.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
---
include/linux/mm.h | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7783073..56cab4e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2147,13 +2147,18 @@ kernel_map_pages(struct page *page, int numpages, int enable)
#ifdef CONFIG_HIBERNATION
extern bool kernel_page_present(struct page *page);
#endif /* CONFIG_HIBERNATION */
-#else
+#else /* CONFIG_DEBUG_PAGEALLOC */
+static inline bool debug_pagealloc_enabled(void)
+{
+ return false;
+}
+
static inline void
kernel_map_pages(struct page *page, int numpages, int enable) {}
#ifdef CONFIG_HIBERNATION
static inline bool kernel_page_present(struct page *page) { return true; }
#endif /* CONFIG_HIBERNATION */
-#endif
+#endif /* CONFIG_DEBUG_PAGEALLOC */
#ifdef __HAVE_ARCH_GATE_AREA
extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
--
2.3.0
--
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^ permalink raw reply related [flat|nested] 14+ messages in thread* Re: [PATCH v2 1/3] mm: provide debug_pagealloc_enabled() without CONFIG_DEBUG_PAGEALLOC
2016-01-27 8:50 ` Christian Borntraeger
@ 2016-01-27 9:15 ` Thomas Gleixner
-1 siblings, 0 replies; 14+ messages in thread
From: Thomas Gleixner @ 2016-01-27 9:15 UTC (permalink / raw)
To: Christian Borntraeger
Cc: linux-kernel, akpm, linux-mm, linux-arch, linux-s390, x86,
linuxppc-dev, davem, Joonsoo Kim, davej
On Wed, 27 Jan 2016, Christian Borntraeger wrote:
> We can provide debug_pagealloc_enabled() also if CONFIG_DEBUG_PAGEALLOC
> is not set. It will return false in that case.
>
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 1/3] mm: provide debug_pagealloc_enabled() without CONFIG_DEBUG_PAGEALLOC
@ 2016-01-27 9:15 ` Thomas Gleixner
0 siblings, 0 replies; 14+ messages in thread
From: Thomas Gleixner @ 2016-01-27 9:15 UTC (permalink / raw)
To: Christian Borntraeger
Cc: linux-kernel, akpm, linux-mm, linux-arch, linux-s390, x86,
linuxppc-dev, davem, Joonsoo Kim, davej
On Wed, 27 Jan 2016, Christian Borntraeger wrote:
> We can provide debug_pagealloc_enabled() also if CONFIG_DEBUG_PAGEALLOC
> is not set. It will return false in that case.
>
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
--
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^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 2/3] x86: query dynamic DEBUG_PAGEALLOC setting
2016-01-27 8:50 ` Christian Borntraeger
@ 2016-01-27 8:50 ` Christian Borntraeger
-1 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
We can use debug_pagealloc_enabled() to check if we can map
the identity mapping with 2MB pages. We can also add the state
into the dump_stack output.
The patch does not touch the code for the 1GB pages, which ignored
CONFIG_DEBUG_PAGEALLOC. Do we need to fence this as well?
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/x86/kernel/dumpstack.c | 5 ++---
arch/x86/mm/init.c | 7 ++++---
arch/x86/mm/pageattr.c | 14 ++++----------
3 files changed, 10 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 9c30acf..32e5699 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -265,9 +265,8 @@ int __die(const char *str, struct pt_regs *regs, long err)
#ifdef CONFIG_SMP
printk("SMP ");
#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
- printk("DEBUG_PAGEALLOC ");
-#endif
+ if (debug_pagealloc_enabled())
+ printk("DEBUG_PAGEALLOC ");
#ifdef CONFIG_KASAN
printk("KASAN");
#endif
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 493f541..39823fd 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -150,13 +150,14 @@ static int page_size_mask;
static void __init probe_page_size_mask(void)
{
-#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK)
+#if !defined(CONFIG_KMEMCHECK)
/*
- * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
+ * For CONFIG_KMEMCHECK or pagealloc debugging, identity mapping will
+ * use small pages.
* This will simplify cpa(), which otherwise needs to support splitting
* large pages into small in interrupt context, etc.
*/
- if (cpu_has_pse)
+ if (cpu_has_pse && !debug_pagealloc_enabled())
page_size_mask |= 1 << PG_LEVEL_2M;
#endif
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index a3137a4..a49c8fd 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -103,12 +103,6 @@ static inline unsigned long highmap_end_pfn(void)
#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
-# define debug_pagealloc 1
-#else
-# define debug_pagealloc 0
-#endif
-
static inline int
within(unsigned long addr, unsigned long start, unsigned long end)
{
@@ -703,10 +697,10 @@ static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
{
struct page *base;
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_unlock(&cpa_lock);
base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0);
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_lock(&cpa_lock);
if (!base)
return -ENOMEM;
@@ -1326,10 +1320,10 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
cpa->numpages = 1;
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_lock(&cpa_lock);
ret = __change_page_attr(cpa, checkalias);
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_unlock(&cpa_lock);
if (ret)
return ret;
--
2.3.0
^ permalink raw reply related [flat|nested] 14+ messages in thread* [PATCH v2 2/3] x86: query dynamic DEBUG_PAGEALLOC setting
@ 2016-01-27 8:50 ` Christian Borntraeger
0 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
We can use debug_pagealloc_enabled() to check if we can map
the identity mapping with 2MB pages. We can also add the state
into the dump_stack output.
The patch does not touch the code for the 1GB pages, which ignored
CONFIG_DEBUG_PAGEALLOC. Do we need to fence this as well?
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/x86/kernel/dumpstack.c | 5 ++---
arch/x86/mm/init.c | 7 ++++---
arch/x86/mm/pageattr.c | 14 ++++----------
3 files changed, 10 insertions(+), 16 deletions(-)
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c
index 9c30acf..32e5699 100644
--- a/arch/x86/kernel/dumpstack.c
+++ b/arch/x86/kernel/dumpstack.c
@@ -265,9 +265,8 @@ int __die(const char *str, struct pt_regs *regs, long err)
#ifdef CONFIG_SMP
printk("SMP ");
#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
- printk("DEBUG_PAGEALLOC ");
-#endif
+ if (debug_pagealloc_enabled())
+ printk("DEBUG_PAGEALLOC ");
#ifdef CONFIG_KASAN
printk("KASAN");
#endif
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 493f541..39823fd 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -150,13 +150,14 @@ static int page_size_mask;
static void __init probe_page_size_mask(void)
{
-#if !defined(CONFIG_DEBUG_PAGEALLOC) && !defined(CONFIG_KMEMCHECK)
+#if !defined(CONFIG_KMEMCHECK)
/*
- * For CONFIG_DEBUG_PAGEALLOC, identity mapping will use small pages.
+ * For CONFIG_KMEMCHECK or pagealloc debugging, identity mapping will
+ * use small pages.
* This will simplify cpa(), which otherwise needs to support splitting
* large pages into small in interrupt context, etc.
*/
- if (cpu_has_pse)
+ if (cpu_has_pse && !debug_pagealloc_enabled())
page_size_mask |= 1 << PG_LEVEL_2M;
#endif
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index a3137a4..a49c8fd 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -103,12 +103,6 @@ static inline unsigned long highmap_end_pfn(void)
#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
-# define debug_pagealloc 1
-#else
-# define debug_pagealloc 0
-#endif
-
static inline int
within(unsigned long addr, unsigned long start, unsigned long end)
{
@@ -703,10 +697,10 @@ static int split_large_page(struct cpa_data *cpa, pte_t *kpte,
{
struct page *base;
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_unlock(&cpa_lock);
base = alloc_pages(GFP_KERNEL | __GFP_NOTRACK, 0);
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_lock(&cpa_lock);
if (!base)
return -ENOMEM;
@@ -1326,10 +1320,10 @@ static int __change_page_attr_set_clr(struct cpa_data *cpa, int checkalias)
if (cpa->flags & (CPA_ARRAY | CPA_PAGES_ARRAY))
cpa->numpages = 1;
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_lock(&cpa_lock);
ret = __change_page_attr(cpa, checkalias);
- if (!debug_pagealloc)
+ if (!debug_pagealloc_enabled())
spin_unlock(&cpa_lock);
if (ret)
return ret;
--
2.3.0
--
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^ permalink raw reply related [flat|nested] 14+ messages in thread* Re: [PATCH v2 2/3] x86: query dynamic DEBUG_PAGEALLOC setting
2016-01-27 8:50 ` Christian Borntraeger
@ 2016-01-27 9:16 ` Thomas Gleixner
-1 siblings, 0 replies; 14+ messages in thread
From: Thomas Gleixner @ 2016-01-27 9:16 UTC (permalink / raw)
To: Christian Borntraeger
Cc: linux-kernel, akpm, linux-mm, linux-arch, linux-s390, x86,
linuxppc-dev, davem, Joonsoo Kim, davej
On Wed, 27 Jan 2016, Christian Borntraeger wrote:
> We can use debug_pagealloc_enabled() to check if we can map
> the identity mapping with 2MB pages. We can also add the state
> into the dump_stack output.
>
> The patch does not touch the code for the 1GB pages, which ignored
> CONFIG_DEBUG_PAGEALLOC. Do we need to fence this as well?
>
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 2/3] x86: query dynamic DEBUG_PAGEALLOC setting
@ 2016-01-27 9:16 ` Thomas Gleixner
0 siblings, 0 replies; 14+ messages in thread
From: Thomas Gleixner @ 2016-01-27 9:16 UTC (permalink / raw)
To: Christian Borntraeger
Cc: linux-kernel, akpm, linux-mm, linux-arch, linux-s390, x86,
linuxppc-dev, davem, Joonsoo Kim, davej
On Wed, 27 Jan 2016, Christian Borntraeger wrote:
> We can use debug_pagealloc_enabled() to check if we can map
> the identity mapping with 2MB pages. We can also add the state
> into the dump_stack output.
>
> The patch does not touch the code for the 1GB pages, which ignored
> CONFIG_DEBUG_PAGEALLOC. Do we need to fence this as well?
>
> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
--
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^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v2 3/3] s390: query dynamic DEBUG_PAGEALLOC setting
2016-01-27 8:50 ` Christian Borntraeger
@ 2016-01-27 8:50 ` Christian Borntraeger
-1 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
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>
---
arch/s390/kernel/dumpstack.c | 8 ++++----
arch/s390/mm/vmem.c | 10 ++++------
2 files changed, 8 insertions(+), 10 deletions(-)
diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
index dc8e204..3f352e9 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>
@@ -184,10 +185,9 @@ void die(struct pt_regs *regs, const char *str)
#endif
#ifdef CONFIG_SMP
printk("SMP ");
-#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
- printk("DEBUG_PAGEALLOC");
-#endif
+#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
^ permalink raw reply related [flat|nested] 14+ messages in thread* [PATCH v2 3/3] s390: query dynamic DEBUG_PAGEALLOC setting
@ 2016-01-27 8:50 ` Christian Borntraeger
0 siblings, 0 replies; 14+ messages in thread
From: Christian Borntraeger @ 2016-01-27 8:50 UTC (permalink / raw)
To: linux-kernel
Cc: akpm, linux-mm, linux-arch, linux-s390, x86, linuxppc-dev, davem,
Joonsoo Kim, davej, Christian Borntraeger
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>
---
arch/s390/kernel/dumpstack.c | 8 ++++----
arch/s390/mm/vmem.c | 10 ++++------
2 files changed, 8 insertions(+), 10 deletions(-)
diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
index dc8e204..3f352e9 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>
@@ -184,10 +185,9 @@ void die(struct pt_regs *regs, const char *str)
#endif
#ifdef CONFIG_SMP
printk("SMP ");
-#endif
-#ifdef CONFIG_DEBUG_PAGEALLOC
- printk("DEBUG_PAGEALLOC");
-#endif
+#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
--
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^ permalink raw reply related [flat|nested] 14+ messages in thread* Re: [PATCH v2 3/3] s390: query dynamic DEBUG_PAGEALLOC setting
2016-01-27 8:50 ` Christian Borntraeger
@ 2016-01-27 9:55 ` Heiko Carstens
-1 siblings, 0 replies; 14+ messages in thread
From: Heiko Carstens @ 2016-01-27 9:55 UTC (permalink / raw)
To: Christian Borntraeger
Cc: linux-kernel, akpm, linux-mm, linux-arch, linux-s390, x86,
linuxppc-dev, davem, Joonsoo Kim, davej
On Wed, Jan 27, 2016 at 09:50:18AM +0100, Christian Borntraeger wrote:
> 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>
> ---
> arch/s390/kernel/dumpstack.c | 8 ++++----
> arch/s390/mm/vmem.c | 10 ++++------
> 2 files changed, 8 insertions(+), 10 deletions(-)
>
> diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
> index dc8e204..3f352e9 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>
> @@ -184,10 +185,9 @@ void die(struct pt_regs *regs, const char *str)
> #endif
> #ifdef CONFIG_SMP
> printk("SMP ");
> -#endif
> -#ifdef CONFIG_DEBUG_PAGEALLOC
> - printk("DEBUG_PAGEALLOC");
> -#endif
> +#endif
> +if (debug_pagealloc_enabled())
> + printk("DEBUG_PAGEALLOC");
> printk("\n");
Indentation is broken ("if").
Besides that
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
^ permalink raw reply [flat|nested] 14+ messages in thread* Re: [PATCH v2 3/3] s390: query dynamic DEBUG_PAGEALLOC setting
@ 2016-01-27 9:55 ` Heiko Carstens
0 siblings, 0 replies; 14+ messages in thread
From: Heiko Carstens @ 2016-01-27 9:55 UTC (permalink / raw)
To: Christian Borntraeger
Cc: linux-kernel, akpm, linux-mm, linux-arch, linux-s390, x86,
linuxppc-dev, davem, Joonsoo Kim, davej
On Wed, Jan 27, 2016 at 09:50:18AM +0100, Christian Borntraeger wrote:
> 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>
> ---
> arch/s390/kernel/dumpstack.c | 8 ++++----
> arch/s390/mm/vmem.c | 10 ++++------
> 2 files changed, 8 insertions(+), 10 deletions(-)
>
> diff --git a/arch/s390/kernel/dumpstack.c b/arch/s390/kernel/dumpstack.c
> index dc8e204..3f352e9 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>
> @@ -184,10 +185,9 @@ void die(struct pt_regs *regs, const char *str)
> #endif
> #ifdef CONFIG_SMP
> printk("SMP ");
> -#endif
> -#ifdef CONFIG_DEBUG_PAGEALLOC
> - printk("DEBUG_PAGEALLOC");
> -#endif
> +#endif
> +if (debug_pagealloc_enabled())
> + printk("DEBUG_PAGEALLOC");
> printk("\n");
Indentation is broken ("if").
Besides that
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
--
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^ permalink raw reply [flat|nested] 14+ messages in thread