* [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo
@ 2021-05-26 17:46 Stephen Brennan
2021-05-27 9:15 ` Greg KH
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: Stephen Brennan @ 2021-05-26 17:46 UTC (permalink / raw)
To: stable
Cc: Stephen Brennan, Andrew Morton, linux-mm, linux-kernel,
Christoph Lameter, Mel Gorman, Andy Whitcroft, Aruna Ramakrishna,
Khalid Aziz
Commit 93b3a674485f6a4b8ffff85d1682d5e8b7c51560 upstream
Commit 93b3a674485f ("mm,vmstat: reduce zone->lock holding time by
/proc/pagetypeinfo") upstream caps the number of iterations over each
free_list at 100,000, and also drops the zone->lock in between each
migrate type. Capping the iteration count alters the file contents in
some cases, which means this approach may not be suitable for stable
backports.
However, dropping zone->lock in between migrate types (and, as a result,
page orders) will not change the /proc/pagetypeinfo file contents. It
can significantly reduce the length of time spent with IRQs disabled,
which can prevent missed interrupts or soft lockups which we have
observed on systems with particularly large memory.
Thus, this commit is a modified version of the upstream one which only
drops the lock in between migrate types.
Fixes: 467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
---
mm/vmstat.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 13b74c4314a7e..663069cf7724a 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1316,6 +1316,9 @@ static void pagetypeinfo_showfree_print(struct seq_file *m,
list_for_each(curr, &area->free_list[mtype])
freecount++;
seq_printf(m, "%6lu ", freecount);
+ spin_unlock_irq(&zone->lock);
+ cond_resched();
+ spin_lock_irq(&zone->lock);
}
seq_putc(m, '\n');
}
--
2.27.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo
2021-05-26 17:46 [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo Stephen Brennan
@ 2021-05-27 9:15 ` Greg KH
2021-05-27 9:22 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.4-stable tree gregkh
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Greg KH @ 2021-05-27 9:15 UTC (permalink / raw)
To: Stephen Brennan
Cc: stable, Andrew Morton, linux-mm, linux-kernel, Christoph Lameter,
Mel Gorman, Andy Whitcroft, Aruna Ramakrishna, Khalid Aziz
On Wed, May 26, 2021 at 10:46:13AM -0700, Stephen Brennan wrote:
> Commit 93b3a674485f6a4b8ffff85d1682d5e8b7c51560 upstream
>
> Commit 93b3a674485f ("mm,vmstat: reduce zone->lock holding time by
> /proc/pagetypeinfo") upstream caps the number of iterations over each
> free_list at 100,000, and also drops the zone->lock in between each
> migrate type. Capping the iteration count alters the file contents in
> some cases, which means this approach may not be suitable for stable
> backports.
>
> However, dropping zone->lock in between migrate types (and, as a result,
> page orders) will not change the /proc/pagetypeinfo file contents. It
> can significantly reduce the length of time spent with IRQs disabled,
> which can prevent missed interrupts or soft lockups which we have
> observed on systems with particularly large memory.
>
> Thus, this commit is a modified version of the upstream one which only
> drops the lock in between migrate types.
Now queued up, thanks.
greg k-h
^ permalink raw reply [flat|nested] 6+ messages in thread
* Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.4-stable tree
2021-05-26 17:46 [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo Stephen Brennan
2021-05-27 9:15 ` Greg KH
@ 2021-05-27 9:22 ` gregkh
2021-05-27 9:23 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.9-stable tree gregkh
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: gregkh @ 2021-05-27 9:22 UTC (permalink / raw)
To: akpm, apw, aruna.ramakrishna, clameter, gregkh, khalid.aziz,
linux-mm, mel, stephen.s.brennan
Cc: stable-commits
This is a note to let you know that I've just added the patch titled
mm, vmstat: drop zone->lock in /proc/pagetypeinfo
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
From foo@baz Thu May 27 11:14:38 AM CEST 2021
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Date: Wed, 26 May 2021 10:46:13 -0700
Subject: mm, vmstat: drop zone->lock in /proc/pagetypeinfo
To: stable@vger.kernel.org
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>, Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter <clameter@sgi.com>, Mel Gorman <mel@csn.ul.ie>, Andy Whitcroft <apw@shadowen.org>, Aruna Ramakrishna <aruna.ramakrishna@oracle.com>, Khalid Aziz <khalid.aziz@oracle.com>
Message-ID: <20210526174613.339990-1-stephen.s.brennan@oracle.com>
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Commit 93b3a674485f6a4b8ffff85d1682d5e8b7c51560 upstream
Commit 93b3a674485f ("mm,vmstat: reduce zone->lock holding time by
/proc/pagetypeinfo") upstream caps the number of iterations over each
free_list at 100,000, and also drops the zone->lock in between each
migrate type. Capping the iteration count alters the file contents in
some cases, which means this approach may not be suitable for stable
backports.
However, dropping zone->lock in between migrate types (and, as a result,
page orders) will not change the /proc/pagetypeinfo file contents. It
can significantly reduce the length of time spent with IRQs disabled,
which can prevent missed interrupts or soft lockups which we have
observed on systems with particularly large memory.
Thus, this commit is a modified version of the upstream one which only
drops the lock in between migrate types.
Fixes: 467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
mm/vmstat.c | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -973,6 +973,9 @@ static void pagetypeinfo_showfree_print(
list_for_each(curr, &area->free_list[mtype])
freecount++;
seq_printf(m, "%6lu ", freecount);
+ spin_unlock_irq(&zone->lock);
+ cond_resched();
+ spin_lock_irq(&zone->lock);
}
seq_putc(m, '\n');
}
Patches currently in stable-queue which might be from stephen.s.brennan@oracle.com are
queue-4.4/mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.9-stable tree
2021-05-26 17:46 [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo Stephen Brennan
2021-05-27 9:15 ` Greg KH
2021-05-27 9:22 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.4-stable tree gregkh
@ 2021-05-27 9:23 ` gregkh
2021-05-27 9:23 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.14-stable tree gregkh
2021-05-27 9:24 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.19-stable tree gregkh
4 siblings, 0 replies; 6+ messages in thread
From: gregkh @ 2021-05-27 9:23 UTC (permalink / raw)
To: akpm, apw, aruna.ramakrishna, clameter, gregkh, khalid.aziz,
linux-mm, mel, stephen.s.brennan
Cc: stable-commits
This is a note to let you know that I've just added the patch titled
mm, vmstat: drop zone->lock in /proc/pagetypeinfo
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
From foo@baz Thu May 27 11:14:38 AM CEST 2021
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Date: Wed, 26 May 2021 10:46:13 -0700
Subject: mm, vmstat: drop zone->lock in /proc/pagetypeinfo
To: stable@vger.kernel.org
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>, Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter <clameter@sgi.com>, Mel Gorman <mel@csn.ul.ie>, Andy Whitcroft <apw@shadowen.org>, Aruna Ramakrishna <aruna.ramakrishna@oracle.com>, Khalid Aziz <khalid.aziz@oracle.com>
Message-ID: <20210526174613.339990-1-stephen.s.brennan@oracle.com>
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Commit 93b3a674485f6a4b8ffff85d1682d5e8b7c51560 upstream
Commit 93b3a674485f ("mm,vmstat: reduce zone->lock holding time by
/proc/pagetypeinfo") upstream caps the number of iterations over each
free_list at 100,000, and also drops the zone->lock in between each
migrate type. Capping the iteration count alters the file contents in
some cases, which means this approach may not be suitable for stable
backports.
However, dropping zone->lock in between migrate types (and, as a result,
page orders) will not change the /proc/pagetypeinfo file contents. It
can significantly reduce the length of time spent with IRQs disabled,
which can prevent missed interrupts or soft lockups which we have
observed on systems with particularly large memory.
Thus, this commit is a modified version of the upstream one which only
drops the lock in between migrate types.
Fixes: 467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
mm/vmstat.c | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1178,6 +1178,9 @@ static void pagetypeinfo_showfree_print(
list_for_each(curr, &area->free_list[mtype])
freecount++;
seq_printf(m, "%6lu ", freecount);
+ spin_unlock_irq(&zone->lock);
+ cond_resched();
+ spin_lock_irq(&zone->lock);
}
seq_putc(m, '\n');
}
Patches currently in stable-queue which might be from stephen.s.brennan@oracle.com are
queue-4.9/mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.14-stable tree
2021-05-26 17:46 [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo Stephen Brennan
` (2 preceding siblings ...)
2021-05-27 9:23 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.9-stable tree gregkh
@ 2021-05-27 9:23 ` gregkh
2021-05-27 9:24 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.19-stable tree gregkh
4 siblings, 0 replies; 6+ messages in thread
From: gregkh @ 2021-05-27 9:23 UTC (permalink / raw)
To: akpm, apw, aruna.ramakrishna, clameter, gregkh, khalid.aziz,
linux-mm, mel, stephen.s.brennan
Cc: stable-commits
This is a note to let you know that I've just added the patch titled
mm, vmstat: drop zone->lock in /proc/pagetypeinfo
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
From foo@baz Thu May 27 11:14:38 AM CEST 2021
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Date: Wed, 26 May 2021 10:46:13 -0700
Subject: mm, vmstat: drop zone->lock in /proc/pagetypeinfo
To: stable@vger.kernel.org
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>, Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter <clameter@sgi.com>, Mel Gorman <mel@csn.ul.ie>, Andy Whitcroft <apw@shadowen.org>, Aruna Ramakrishna <aruna.ramakrishna@oracle.com>, Khalid Aziz <khalid.aziz@oracle.com>
Message-ID: <20210526174613.339990-1-stephen.s.brennan@oracle.com>
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Commit 93b3a674485f6a4b8ffff85d1682d5e8b7c51560 upstream
Commit 93b3a674485f ("mm,vmstat: reduce zone->lock holding time by
/proc/pagetypeinfo") upstream caps the number of iterations over each
free_list at 100,000, and also drops the zone->lock in between each
migrate type. Capping the iteration count alters the file contents in
some cases, which means this approach may not be suitable for stable
backports.
However, dropping zone->lock in between migrate types (and, as a result,
page orders) will not change the /proc/pagetypeinfo file contents. It
can significantly reduce the length of time spent with IRQs disabled,
which can prevent missed interrupts or soft lockups which we have
observed on systems with particularly large memory.
Thus, this commit is a modified version of the upstream one which only
drops the lock in between migrate types.
Fixes: 467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
mm/vmstat.c | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1313,6 +1313,9 @@ static void pagetypeinfo_showfree_print(
list_for_each(curr, &area->free_list[mtype])
freecount++;
seq_printf(m, "%6lu ", freecount);
+ spin_unlock_irq(&zone->lock);
+ cond_resched();
+ spin_lock_irq(&zone->lock);
}
seq_putc(m, '\n');
}
Patches currently in stable-queue which might be from stephen.s.brennan@oracle.com are
queue-4.14/mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.19-stable tree
2021-05-26 17:46 [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo Stephen Brennan
` (3 preceding siblings ...)
2021-05-27 9:23 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.14-stable tree gregkh
@ 2021-05-27 9:24 ` gregkh
4 siblings, 0 replies; 6+ messages in thread
From: gregkh @ 2021-05-27 9:24 UTC (permalink / raw)
To: akpm, apw, aruna.ramakrishna, clameter, gregkh, khalid.aziz,
linux-mm, mel, stephen.s.brennan
Cc: stable-commits
This is a note to let you know that I've just added the patch titled
mm, vmstat: drop zone->lock in /proc/pagetypeinfo
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
From foo@baz Thu May 27 11:14:38 AM CEST 2021
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Date: Wed, 26 May 2021 10:46:13 -0700
Subject: mm, vmstat: drop zone->lock in /proc/pagetypeinfo
To: stable@vger.kernel.org
Cc: Stephen Brennan <stephen.s.brennan@oracle.com>, Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Christoph Lameter <clameter@sgi.com>, Mel Gorman <mel@csn.ul.ie>, Andy Whitcroft <apw@shadowen.org>, Aruna Ramakrishna <aruna.ramakrishna@oracle.com>, Khalid Aziz <khalid.aziz@oracle.com>
Message-ID: <20210526174613.339990-1-stephen.s.brennan@oracle.com>
From: Stephen Brennan <stephen.s.brennan@oracle.com>
Commit 93b3a674485f6a4b8ffff85d1682d5e8b7c51560 upstream
Commit 93b3a674485f ("mm,vmstat: reduce zone->lock holding time by
/proc/pagetypeinfo") upstream caps the number of iterations over each
free_list at 100,000, and also drops the zone->lock in between each
migrate type. Capping the iteration count alters the file contents in
some cases, which means this approach may not be suitable for stable
backports.
However, dropping zone->lock in between migrate types (and, as a result,
page orders) will not change the /proc/pagetypeinfo file contents. It
can significantly reduce the length of time spent with IRQs disabled,
which can prevent missed interrupts or soft lockups which we have
observed on systems with particularly large memory.
Thus, this commit is a modified version of the upstream one which only
drops the lock in between migrate types.
Fixes: 467c996c1e19 ("Print out statistics in relation to fragmentation avoidance to /proc/pagetypeinfo")
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
mm/vmstat.c | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1384,6 +1384,9 @@ static void pagetypeinfo_showfree_print(
list_for_each(curr, &area->free_list[mtype])
freecount++;
seq_printf(m, "%6lu ", freecount);
+ spin_unlock_irq(&zone->lock);
+ cond_resched();
+ spin_lock_irq(&zone->lock);
}
seq_putc(m, '\n');
}
Patches currently in stable-queue which might be from stephen.s.brennan@oracle.com are
queue-4.19/mm-vmstat-drop-zone-lock-in-proc-pagetypeinfo.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-05-27 9:24 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2021-05-26 17:46 [PATCH STABLE 4.4-5.3] mm, vmstat: drop zone->lock in /proc/pagetypeinfo Stephen Brennan
2021-05-27 9:15 ` Greg KH
2021-05-27 9:22 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.4-stable tree gregkh
2021-05-27 9:23 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.9-stable tree gregkh
2021-05-27 9:23 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.14-stable tree gregkh
2021-05-27 9:24 ` Patch "mm, vmstat: drop zone->lock in /proc/pagetypeinfo" has been added to the 4.19-stable tree gregkh
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