* [v3 0/2] recalculate min_free_kbytes post memory hotplug
@ 2020-09-17 1:21 Vijay Balakrishna
2020-09-17 1:21 ` [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Vijay Balakrishna
2020-09-17 1:21 ` [v3 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user Vijay Balakrishna
0 siblings, 2 replies; 9+ messages in thread
From: Vijay Balakrishna @ 2020-09-17 1:21 UTC (permalink / raw)
To: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Vijay Balakrishna,
Michal Hocko, Allen Pais
Cc: linux-kernel, linux-mm
v2 -> v3
--------
[v2 1/2]
- removed symptoms references from changelog
[v2 2/2]
- addressed following issues Michal Hocko raised:
. nr_free_buffer_pages can oveflow in int on very large machines
. min_free_kbytes can decrease the size theoretically
v1 -> v2
--------
- addressed issue Kirill A. Shutemov raised:
. changes would override min_free_kbytes set by user
Vijay Balakrishna (2):
mm: khugepaged: recalculate min_free_kbytes after memory hotplug as
expected by khugepaged
mm: khugepaged: avoid overriding min_free_kbytes set by user
include/linux/khugepaged.h | 5 +++++
mm/khugepaged.c | 16 +++++++++++++---
mm/memory_hotplug.c | 3 +++
mm/page_alloc.c | 2 +-
4 files changed, 22 insertions(+), 4 deletions(-)
--
2.28.0
^ permalink raw reply [flat|nested] 9+ messages in thread
* [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged
2020-09-17 1:21 [v3 0/2] recalculate min_free_kbytes post memory hotplug Vijay Balakrishna
@ 2020-09-17 1:21 ` Vijay Balakrishna
2020-09-23 21:27 ` Vijay Balakrishna
2020-09-25 7:42 ` Michal Hocko
2020-09-17 1:21 ` [v3 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user Vijay Balakrishna
1 sibling, 2 replies; 9+ messages in thread
From: Vijay Balakrishna @ 2020-09-17 1:21 UTC (permalink / raw)
To: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Vijay Balakrishna,
Michal Hocko, Allen Pais
Cc: linux-kernel, linux-mm
When memory is hotplug added or removed the min_free_kbytes must be
recalculated based on what is expected by khugepaged. Currently
after hotplug, min_free_kbytes will be set to a lower default and higher
default set when THP enabled is lost. This change restores min_free_kbytes
as expected for THP consumers.
Fixes: f000565adb77 ("thp: set recommended min free kbytes")
Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Cc: stable@vger.kernel.org
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
---
include/linux/khugepaged.h | 5 +++++
mm/khugepaged.c | 13 +++++++++++--
mm/memory_hotplug.c | 3 +++
3 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/include/linux/khugepaged.h b/include/linux/khugepaged.h
index bc45ea1efbf7..c941b7377321 100644
--- a/include/linux/khugepaged.h
+++ b/include/linux/khugepaged.h
@@ -15,6 +15,7 @@ extern int __khugepaged_enter(struct mm_struct *mm);
extern void __khugepaged_exit(struct mm_struct *mm);
extern int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
unsigned long vm_flags);
+extern void khugepaged_min_free_kbytes_update(void);
#ifdef CONFIG_SHMEM
extern void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr);
#else
@@ -85,6 +86,10 @@ static inline void collapse_pte_mapped_thp(struct mm_struct *mm,
unsigned long addr)
{
}
+
+static inline void khugepaged_min_free_kbytes_update(void)
+{
+}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#endif /* _LINUX_KHUGEPAGED_H */
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index cfa0dba5fd3b..4f7107476a6f 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -56,6 +56,9 @@ enum scan_result {
#define CREATE_TRACE_POINTS
#include <trace/events/huge_memory.h>
+static struct task_struct *khugepaged_thread __read_mostly;
+static DEFINE_MUTEX(khugepaged_mutex);
+
/* default scan 8*512 pte (or vmas) every 30 second */
static unsigned int khugepaged_pages_to_scan __read_mostly;
static unsigned int khugepaged_pages_collapsed;
@@ -2292,8 +2295,6 @@ static void set_recommended_min_free_kbytes(void)
int start_stop_khugepaged(void)
{
- static struct task_struct *khugepaged_thread __read_mostly;
- static DEFINE_MUTEX(khugepaged_mutex);
int err = 0;
mutex_lock(&khugepaged_mutex);
@@ -2320,3 +2321,11 @@ int start_stop_khugepaged(void)
mutex_unlock(&khugepaged_mutex);
return err;
}
+
+void khugepaged_min_free_kbytes_update(void)
+{
+ mutex_lock(&khugepaged_mutex);
+ if (khugepaged_enabled() && khugepaged_thread)
+ set_recommended_min_free_kbytes();
+ mutex_unlock(&khugepaged_mutex);
+}
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index e9d5ab5d3ca0..3e19272c1fad 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -36,6 +36,7 @@
#include <linux/memblock.h>
#include <linux/compaction.h>
#include <linux/rmap.h>
+#include <linux/khugepaged.h>
#include <asm/tlbflush.h>
@@ -857,6 +858,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
zone_pcp_update(zone);
init_per_zone_wmark_min();
+ khugepaged_min_free_kbytes_update();
kswapd_run(nid);
kcompactd_run(nid);
@@ -1600,6 +1602,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
pgdat_resize_unlock(zone->zone_pgdat, &flags);
init_per_zone_wmark_min();
+ khugepaged_min_free_kbytes_update();
if (!populated_zone(zone)) {
zone_pcp_reset(zone);
--
2.28.0
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [v3 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user
2020-09-17 1:21 [v3 0/2] recalculate min_free_kbytes post memory hotplug Vijay Balakrishna
2020-09-17 1:21 ` [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Vijay Balakrishna
@ 2020-09-17 1:21 ` Vijay Balakrishna
2020-09-17 4:22 ` Vijay Balakrishna
1 sibling, 1 reply; 9+ messages in thread
From: Vijay Balakrishna @ 2020-09-17 1:21 UTC (permalink / raw)
To: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Vijay Balakrishna,
Michal Hocko, Allen Pais
Cc: linux-kernel, linux-mm
set_recommended_min_free_kbytes need to honor min_free_kbytes set by the
user. Post start-of-day THP enable or memory hotplug operations can
lose user specified min_free_kbytes, in particular when it is higher than
calculated recommended value. user_min_free_kbytes initialized to 0
to avoid undesired result when comparing with "unsigned long" type.
Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Cc: stable@vger.kernel.org
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
---
mm/khugepaged.c | 3 ++-
mm/page_alloc.c | 2 +-
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 4f7107476a6f..3c1147816d12 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -2283,7 +2283,8 @@ static void set_recommended_min_free_kbytes(void)
(unsigned long) nr_free_buffer_pages() / 20);
recommended_min <<= (PAGE_SHIFT-10);
- if (recommended_min > min_free_kbytes) {
+ if (recommended_min > min_free_kbytes ||
+ recommended_min > user_min_free_kbytes) {
if (user_min_free_kbytes >= 0)
pr_info("raising min_free_kbytes from %d to %lu to help transparent hugepage allocations\n",
min_free_kbytes, recommended_min);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index fab5e97dc9ca..7b81fb139034 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -315,7 +315,7 @@ compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = {
};
int min_free_kbytes = 1024;
-int user_min_free_kbytes = -1;
+int user_min_free_kbytes = 0;
#ifdef CONFIG_DISCONTIGMEM
/*
* DiscontigMem defines memory ranges as separate pg_data_t even if the ranges
--
2.28.0
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [v3 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user
2020-09-17 1:21 ` [v3 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user Vijay Balakrishna
@ 2020-09-17 4:22 ` Vijay Balakrishna
0 siblings, 0 replies; 9+ messages in thread
From: Vijay Balakrishna @ 2020-09-17 4:22 UTC (permalink / raw)
To: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Michal Hocko, Allen Pais
Cc: linux-kernel, linux-mm
Please ignore this patch. I forgot to run scripts/checkpatch.pl and see
CHECK: Alignment should match open parenthesis
#30: FILE: mm/khugepaged.c:2287:
+ if (recommended_min > min_free_kbytes ||
+ recommended_min > user_min_free_kbytes) {
ERROR: do not initialise globals to 0
#43: FILE: mm/page_alloc.c:318:
+int user_min_free_kbytes = 0;
Sorry for trouble, I will send a new version.
Vijay
On 9/16/2020 6:21 PM, Vijay Balakrishna wrote:
> set_recommended_min_free_kbytes need to honor min_free_kbytes set by the
> user. Post start-of-day THP enable or memory hotplug operations can
> lose user specified min_free_kbytes, in particular when it is higher than
> calculated recommended value. user_min_free_kbytes initialized to 0
> to avoid undesired result when comparing with "unsigned long" type.
>
> Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
> Cc: stable@vger.kernel.org
> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
> ---
> mm/khugepaged.c | 3 ++-
> mm/page_alloc.c | 2 +-
> 2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index 4f7107476a6f..3c1147816d12 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -2283,7 +2283,8 @@ static void set_recommended_min_free_kbytes(void)
> (unsigned long) nr_free_buffer_pages() / 20);
> recommended_min <<= (PAGE_SHIFT-10);
>
> - if (recommended_min > min_free_kbytes) {
> + if (recommended_min > min_free_kbytes ||
> + recommended_min > user_min_free_kbytes) {
> if (user_min_free_kbytes >= 0)
> pr_info("raising min_free_kbytes from %d to %lu to help transparent hugepage allocations\n",
> min_free_kbytes, recommended_min);
> diff --git a/mm/page_alloc.c b/mm/page_alloc.c
> index fab5e97dc9ca..7b81fb139034 100644
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -315,7 +315,7 @@ compound_page_dtor * const compound_page_dtors[NR_COMPOUND_DTORS] = {
> };
>
> int min_free_kbytes = 1024;
> -int user_min_free_kbytes = -1;
> +int user_min_free_kbytes = 0;
> #ifdef CONFIG_DISCONTIGMEM
> /*
> * DiscontigMem defines memory ranges as separate pg_data_t even if the ranges
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged
2020-09-17 1:21 ` [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Vijay Balakrishna
@ 2020-09-23 21:27 ` Vijay Balakrishna
2020-09-25 2:51 ` Andrew Morton
2020-09-25 7:42 ` Michal Hocko
1 sibling, 1 reply; 9+ messages in thread
From: Vijay Balakrishna @ 2020-09-23 21:27 UTC (permalink / raw)
To: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Michal Hocko, Allen Pais
Cc: linux-kernel, linux-mm
Can this patch be included? As Kirill is ok with patch now.
Thanks,
Vijay
On 9/16/2020 6:21 PM, Vijay Balakrishna wrote:
> When memory is hotplug added or removed the min_free_kbytes must be
> recalculated based on what is expected by khugepaged. Currently
> after hotplug, min_free_kbytes will be set to a lower default and higher
> default set when THP enabled is lost. This change restores min_free_kbytes
> as expected for THP consumers.
>
> Fixes: f000565adb77 ("thp: set recommended min free kbytes")
>
> Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
> Cc: stable@vger.kernel.org
> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
> ---
> include/linux/khugepaged.h | 5 +++++
> mm/khugepaged.c | 13 +++++++++++--
> mm/memory_hotplug.c | 3 +++
> 3 files changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/khugepaged.h b/include/linux/khugepaged.h
> index bc45ea1efbf7..c941b7377321 100644
> --- a/include/linux/khugepaged.h
> +++ b/include/linux/khugepaged.h
> @@ -15,6 +15,7 @@ extern int __khugepaged_enter(struct mm_struct *mm);
> extern void __khugepaged_exit(struct mm_struct *mm);
> extern int khugepaged_enter_vma_merge(struct vm_area_struct *vma,
> unsigned long vm_flags);
> +extern void khugepaged_min_free_kbytes_update(void);
> #ifdef CONFIG_SHMEM
> extern void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr);
> #else
> @@ -85,6 +86,10 @@ static inline void collapse_pte_mapped_thp(struct mm_struct *mm,
> unsigned long addr)
> {
> }
> +
> +static inline void khugepaged_min_free_kbytes_update(void)
> +{
> +}
> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>
> #endif /* _LINUX_KHUGEPAGED_H */
> diff --git a/mm/khugepaged.c b/mm/khugepaged.c
> index cfa0dba5fd3b..4f7107476a6f 100644
> --- a/mm/khugepaged.c
> +++ b/mm/khugepaged.c
> @@ -56,6 +56,9 @@ enum scan_result {
> #define CREATE_TRACE_POINTS
> #include <trace/events/huge_memory.h>
>
> +static struct task_struct *khugepaged_thread __read_mostly;
> +static DEFINE_MUTEX(khugepaged_mutex);
> +
> /* default scan 8*512 pte (or vmas) every 30 second */
> static unsigned int khugepaged_pages_to_scan __read_mostly;
> static unsigned int khugepaged_pages_collapsed;
> @@ -2292,8 +2295,6 @@ static void set_recommended_min_free_kbytes(void)
>
> int start_stop_khugepaged(void)
> {
> - static struct task_struct *khugepaged_thread __read_mostly;
> - static DEFINE_MUTEX(khugepaged_mutex);
> int err = 0;
>
> mutex_lock(&khugepaged_mutex);
> @@ -2320,3 +2321,11 @@ int start_stop_khugepaged(void)
> mutex_unlock(&khugepaged_mutex);
> return err;
> }
> +
> +void khugepaged_min_free_kbytes_update(void)
> +{
> + mutex_lock(&khugepaged_mutex);
> + if (khugepaged_enabled() && khugepaged_thread)
> + set_recommended_min_free_kbytes();
> + mutex_unlock(&khugepaged_mutex);
> +}
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index e9d5ab5d3ca0..3e19272c1fad 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -36,6 +36,7 @@
> #include <linux/memblock.h>
> #include <linux/compaction.h>
> #include <linux/rmap.h>
> +#include <linux/khugepaged.h>
>
> #include <asm/tlbflush.h>
>
> @@ -857,6 +858,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
> zone_pcp_update(zone);
>
> init_per_zone_wmark_min();
> + khugepaged_min_free_kbytes_update();
>
> kswapd_run(nid);
> kcompactd_run(nid);
> @@ -1600,6 +1602,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
> pgdat_resize_unlock(zone->zone_pgdat, &flags);
>
> init_per_zone_wmark_min();
> + khugepaged_min_free_kbytes_update();
>
> if (!populated_zone(zone)) {
> zone_pcp_reset(zone);
>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged
2020-09-23 21:27 ` Vijay Balakrishna
@ 2020-09-25 2:51 ` Andrew Morton
2020-09-25 7:45 ` Michal Hocko
0 siblings, 1 reply; 9+ messages in thread
From: Andrew Morton @ 2020-09-25 2:51 UTC (permalink / raw)
To: Vijay Balakrishna
Cc: Kirill A. Shutemov, Oleg Nesterov, Song Liu, Andrea Arcangeli,
Pavel Tatashin, Michal Hocko, Allen Pais, linux-kernel, linux-mm
On Wed, 23 Sep 2020 14:27:30 -0700 Vijay Balakrishna <vijayb@linux.microsoft.com> wrote:
> Can this patch be included? As Kirill is ok with patch now.
He is? I can't immediately find that email.
Do we have an acked-by?
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged
2020-09-17 1:21 ` [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Vijay Balakrishna
2020-09-23 21:27 ` Vijay Balakrishna
@ 2020-09-25 7:42 ` Michal Hocko
2020-09-25 16:31 ` Vijay Balakrishna
1 sibling, 1 reply; 9+ messages in thread
From: Michal Hocko @ 2020-09-25 7:42 UTC (permalink / raw)
To: Vijay Balakrishna
Cc: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Allen Pais, linux-kernel,
linux-mm
On Wed 16-09-20 18:21:48, Vijay Balakrishna wrote:
> When memory is hotplug added or removed the min_free_kbytes must be
> recalculated based on what is expected by khugepaged. Currently
> after hotplug, min_free_kbytes will be set to a lower default and higher
> default set when THP enabled is lost. This change restores min_free_kbytes
> as expected for THP consumers.
>
> Fixes: f000565adb77 ("thp: set recommended min free kbytes")
>
> Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
> Cc: stable@vger.kernel.org
> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
I am ok with this patch. I am not sure this is worth backporting to
stable trees becasuse this is not a functional bug. Surprising behavior,
yes, but not much more than that.
Acked-by: Michal Hocko <mhocko@suse.com>
One minor comment below
[...]
> @@ -857,6 +858,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
> zone_pcp_update(zone);
>
> init_per_zone_wmark_min();
> + khugepaged_min_free_kbytes_update();
>
> kswapd_run(nid);
> kcompactd_run(nid);
> @@ -1600,6 +1602,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
> pgdat_resize_unlock(zone->zone_pgdat, &flags);
>
> init_per_zone_wmark_min();
> + khugepaged_min_free_kbytes_update();
>
> if (!populated_zone(zone)) {
> zone_pcp_reset(zone);
Can we move khugepaged_min_free_kbytes_update into
init_per_zone_wmark_min? If it stays external we might hit the same
problem when somebody else needs to modify min_free_kbytes. Early init
call will be likely too early for khugepaged but that shouldn't matter
AFAICS because it will call khugepaged_min_free_kbytes_update on its
own.
--
Michal Hocko
SUSE Labs
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged
2020-09-25 2:51 ` Andrew Morton
@ 2020-09-25 7:45 ` Michal Hocko
0 siblings, 0 replies; 9+ messages in thread
From: Michal Hocko @ 2020-09-25 7:45 UTC (permalink / raw)
To: Andrew Morton
Cc: Vijay Balakrishna, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Allen Pais, linux-kernel,
linux-mm
On Thu 24-09-20 19:51:03, Andrew Morton wrote:
> On Wed, 23 Sep 2020 14:27:30 -0700 Vijay Balakrishna <vijayb@linux.microsoft.com> wrote:
>
> > Can this patch be included? As Kirill is ok with patch now.
>
> He is? I can't immediately find that email.
http://lkml.kernel.org/r/20200922070726.dlw24lf3wd3p2ias@black.fi.intel.com
--
Michal Hocko
SUSE Labs
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged
2020-09-25 7:42 ` Michal Hocko
@ 2020-09-25 16:31 ` Vijay Balakrishna
0 siblings, 0 replies; 9+ messages in thread
From: Vijay Balakrishna @ 2020-09-25 16:31 UTC (permalink / raw)
To: Michal Hocko
Cc: Andrew Morton, Kirill A. Shutemov, Oleg Nesterov, Song Liu,
Andrea Arcangeli, Pavel Tatashin, Allen Pais, linux-kernel,
linux-mm
On 9/25/2020 12:42 AM, Michal Hocko wrote:
> On Wed 16-09-20 18:21:48, Vijay Balakrishna wrote:
>> When memory is hotplug added or removed the min_free_kbytes must be
>> recalculated based on what is expected by khugepaged. Currently
>> after hotplug, min_free_kbytes will be set to a lower default and higher
>> default set when THP enabled is lost. This change restores min_free_kbytes
>> as expected for THP consumers.
>>
>> Fixes: f000565adb77 ("thp: set recommended min free kbytes")
>>
>> Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
>> Cc: stable@vger.kernel.org
>> Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
>
> I am ok with this patch. I am not sure this is worth backporting to
> stable trees becasuse this is not a functional bug. Surprising behavior,
> yes, but not much more than that.
>
> Acked-by: Michal Hocko <mhocko@suse.com>
Thanks Michal.
>
> One minor comment below
> [...]
>> @@ -857,6 +858,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages,
>> zone_pcp_update(zone);
>>
>> init_per_zone_wmark_min();
>> + khugepaged_min_free_kbytes_update();
>>
>> kswapd_run(nid);
>> kcompactd_run(nid);
>> @@ -1600,6 +1602,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
>> pgdat_resize_unlock(zone->zone_pgdat, &flags);
>>
>> init_per_zone_wmark_min();
>> + khugepaged_min_free_kbytes_update();
>>
>> if (!populated_zone(zone)) {
>> zone_pcp_reset(zone);
>
> Can we move khugepaged_min_free_kbytes_update into
> init_per_zone_wmark_min? If it stays external we might hit the same
> problem when somebody else needs to modify min_free_kbytes. Early init
> call will be likely too early for khugepaged but that shouldn't matter
> AFAICS because it will call khugepaged_min_free_kbytes_update on its
> own.
Sure, let me take a look and post v4 next week.
Thanks,
Vijay
>
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2020-09-25 16:32 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-09-17 1:21 [v3 0/2] recalculate min_free_kbytes post memory hotplug Vijay Balakrishna
2020-09-17 1:21 ` [v3 1/2] mm: khugepaged: recalculate min_free_kbytes after memory hotplug as expected by khugepaged Vijay Balakrishna
2020-09-23 21:27 ` Vijay Balakrishna
2020-09-25 2:51 ` Andrew Morton
2020-09-25 7:45 ` Michal Hocko
2020-09-25 7:42 ` Michal Hocko
2020-09-25 16:31 ` Vijay Balakrishna
2020-09-17 1:21 ` [v3 2/2] mm: khugepaged: avoid overriding min_free_kbytes set by user Vijay Balakrishna
2020-09-17 4:22 ` Vijay Balakrishna
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).