* [PATCH] Low mem virq incremental adjustments
@ 2012-03-07 16:15 Andres Lagar-Cavilla
2012-03-07 17:02 ` Jan Beulich
0 siblings, 1 reply; 6+ messages in thread
From: Andres Lagar-Cavilla @ 2012-03-07 16:15 UTC (permalink / raw)
To: xen-devel
Cc: dan.magenheimer, ian.campbell, andres, tim, JBeulich, ian.jackson,
adin
.gitignore | 1 +
xen/common/page_alloc.c | 7 +++++--
2 files changed, 6 insertions(+), 2 deletions(-)
Consider tmem before firing the virq.
Add .gitignore rune.
Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
diff -r f7ce6d26635c -r 5651945c7a74 .gitignore
--- a/.gitignore
+++ b/.gitignore
@@ -197,6 +197,7 @@ tools/misc/xen-hvmctx
tools/misc/gtraceview
tools/misc/gtracestat
tools/misc/xenlockprof
+tools/misc/lowmemd
tools/pygrub/build/*
tools/python/build/*
tools/python/xen/util/path.py
diff -r f7ce6d26635c -r 5651945c7a74 xen/common/page_alloc.c
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -377,7 +377,10 @@ static void __init setup_low_mem_virq(vo
static void check_low_mem_virq(void)
{
- if ( unlikely(total_avail_pages <= low_mem_virq_th) )
+ unsigned long avail_pages = total_avail_pages +
+ (opt_tmem) ? tmem_freeable_pages(): 0;
+
+ if ( unlikely(avail_pages <= low_mem_virq_th) )
{
send_global_virq(VIRQ_ENOMEM);
@@ -391,7 +394,7 @@ static void check_low_mem_virq(void)
return;
}
- if ( unlikely(total_avail_pages >= low_mem_virq_high) )
+ if ( unlikely(avail_pages >= low_mem_virq_high) )
{
/* Reset hysteresis. Bring threshold up one order.
* If we are back where originally set, set high
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] Low mem virq incremental adjustments
2012-03-07 16:15 [PATCH] Low mem virq incremental adjustments Andres Lagar-Cavilla
@ 2012-03-07 17:02 ` Jan Beulich
2012-03-07 18:12 ` Andres Lagar-Cavilla
0 siblings, 1 reply; 6+ messages in thread
From: Jan Beulich @ 2012-03-07 17:02 UTC (permalink / raw)
To: Andres Lagar-Cavilla, dan.magenheimer
Cc: ian.campbell, andres, tim, xen-devel, ian.jackson, adin
>>> On 07.03.12 at 17:15, Andres Lagar-Cavilla <andres@lagarcavilla.org> wrote:
> --- a/xen/common/page_alloc.c
> +++ b/xen/common/page_alloc.c
> @@ -377,7 +377,10 @@ static void __init setup_low_mem_virq(vo
>
> static void check_low_mem_virq(void)
> {
> - if ( unlikely(total_avail_pages <= low_mem_virq_th) )
> + unsigned long avail_pages = total_avail_pages +
> + (opt_tmem) ? tmem_freeable_pages(): 0;
Can tmem_freeable_pages() return anything other than zero when
opt_tmem is zero? (I.e. is the [improperly parenthesized!] conditional
expression necessary at all?)
Jan
> +
> + if ( unlikely(avail_pages <= low_mem_virq_th) )
> {
> send_global_virq(VIRQ_ENOMEM);
>
> @@ -391,7 +394,7 @@ static void check_low_mem_virq(void)
> return;
> }
>
> - if ( unlikely(total_avail_pages >= low_mem_virq_high) )
> + if ( unlikely(avail_pages >= low_mem_virq_high) )
> {
> /* Reset hysteresis. Bring threshold up one order.
> * If we are back where originally set, set high
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] Low mem virq incremental adjustments
2012-03-07 17:02 ` Jan Beulich
@ 2012-03-07 18:12 ` Andres Lagar-Cavilla
2012-03-08 21:59 ` Dan Magenheimer
0 siblings, 1 reply; 6+ messages in thread
From: Andres Lagar-Cavilla @ 2012-03-07 18:12 UTC (permalink / raw)
To: Jan Beulich
Cc: dan.magenheimer, ian.campbell, andres, tim, xen-devel,
ian.jackson, adin
> >>> On 07.03.12 at 17:15, Andres Lagar-Cavilla <andres@lagarcavilla.org>
> wrote:
>> --- a/xen/common/page_alloc.c
>> +++ b/xen/common/page_alloc.c
>> @@ -377,7 +377,10 @@ static void __init setup_low_mem_virq(vo
>>
>> static void check_low_mem_virq(void)
>> {
>> - if ( unlikely(total_avail_pages <= low_mem_virq_th) )
>> + unsigned long avail_pages = total_avail_pages +
>> + (opt_tmem) ? tmem_freeable_pages(): 0;
>
> Can tmem_freeable_pages() return anything other than zero when
> opt_tmem is zero? (I.e. is the [improperly parenthesized!] conditional
> expression necessary at all?)
I'm not sure. I'll let Dan take it from here, as he surely knows the right
way. He acked it the way it is.
Andres
>
> Jan
>
>> +
>> + if ( unlikely(avail_pages <= low_mem_virq_th) )
>> {
>> send_global_virq(VIRQ_ENOMEM);
>>
>> @@ -391,7 +394,7 @@ static void check_low_mem_virq(void)
>> return;
>> }
>>
>> - if ( unlikely(total_avail_pages >= low_mem_virq_high) )
>> + if ( unlikely(avail_pages >= low_mem_virq_high) )
>> {
>> /* Reset hysteresis. Bring threshold up one order.
>> * If we are back where originally set, set high
>
>
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] Low mem virq incremental adjustments
2012-03-07 18:12 ` Andres Lagar-Cavilla
@ 2012-03-08 21:59 ` Dan Magenheimer
2012-03-09 9:04 ` Jan Beulich
0 siblings, 1 reply; 6+ messages in thread
From: Dan Magenheimer @ 2012-03-08 21:59 UTC (permalink / raw)
To: andres, Jan Beulich
Cc: ian.campbell, andres, tim, xen-devel, ian.jackson, adin
> From: Andres Lagar-Cavilla [mailto:andres@lagarcavilla.org]
> Sent: Wednesday, March 07, 2012 11:12 AM
> To: Jan Beulich
> Cc: Dan Magenheimer; ian.campbell@citrix.com; ian.jackson@citrix.com; adin@gridcentric.ca;
> andres@gridcentric.ca; xen-devel; tim@xen.org
> Subject: Re: [PATCH] Low mem virq incremental adjustments
>
> > >>> On 07.03.12 at 17:15, Andres Lagar-Cavilla <andres@lagarcavilla.org>
> > wrote:
> >> --- a/xen/common/page_alloc.c
> >> +++ b/xen/common/page_alloc.c
> >> @@ -377,7 +377,10 @@ static void __init setup_low_mem_virq(vo
> >>
> >> static void check_low_mem_virq(void)
> >> {
> >> - if ( unlikely(total_avail_pages <= low_mem_virq_th) )
> >> + unsigned long avail_pages = total_avail_pages +
> >> + (opt_tmem) ? tmem_freeable_pages(): 0;
> >
> > Can tmem_freeable_pages() return anything other than zero when
> > opt_tmem is zero? (I.e. is the [improperly parenthesized!] conditional
> > expression necessary at all?)
>
> I'm not sure. I'll let Dan take it from here, as he surely knows the right
> way. He acked it the way it is.
> Andres
Both would be correct (other than the parentheses).
I was also going to make the same comment about tmem_freeable_pages()
but decided the way Andres coded it is clearer because it doesn't
assume anything about tmem; if tmem is enabled, it uses an
abstract interface this code doesn't need to know anything about.
Anyway, either way is fine with me.
Dan
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] Low mem virq incremental adjustments
2012-03-08 21:59 ` Dan Magenheimer
@ 2012-03-09 9:04 ` Jan Beulich
2012-03-09 9:56 ` Keir Fraser
0 siblings, 1 reply; 6+ messages in thread
From: Jan Beulich @ 2012-03-09 9:04 UTC (permalink / raw)
To: andres
Cc: Dan Magenheimer, ian.campbell, andres, tim, xen-devel,
ian.jackson, adin
>>> On 08.03.12 at 22:59, Dan Magenheimer <dan.magenheimer@oracle.com> wrote:
>> From: Andres Lagar-Cavilla [mailto:andres@lagarcavilla.org]
>> Sent: Wednesday, March 07, 2012 11:12 AM
>> To: Jan Beulich
>> Cc: Dan Magenheimer; ian.campbell@citrix.com; ian.jackson@citrix.com;
> adin@gridcentric.ca;
>> andres@gridcentric.ca; xen-devel; tim@xen.org
>> Subject: Re: [PATCH] Low mem virq incremental adjustments
>>
>> > >>> On 07.03.12 at 17:15, Andres Lagar-Cavilla <andres@lagarcavilla.org>
>> > wrote:
>> >> --- a/xen/common/page_alloc.c
>> >> +++ b/xen/common/page_alloc.c
>> >> @@ -377,7 +377,10 @@ static void __init setup_low_mem_virq(vo
>> >>
>> >> static void check_low_mem_virq(void)
>> >> {
>> >> - if ( unlikely(total_avail_pages <= low_mem_virq_th) )
>> >> + unsigned long avail_pages = total_avail_pages +
>> >> + (opt_tmem) ? tmem_freeable_pages(): 0;
>> >
>> > Can tmem_freeable_pages() return anything other than zero when
>> > opt_tmem is zero? (I.e. is the [improperly parenthesized!] conditional
>> > expression necessary at all?)
>>
>> I'm not sure. I'll let Dan take it from here, as he surely knows the right
>> way. He acked it the way it is.
>> Andres
>
> Both would be correct (other than the parentheses).
>
> I was also going to make the same comment about tmem_freeable_pages()
> but decided the way Andres coded it is clearer because it doesn't
> assume anything about tmem; if tmem is enabled, it uses an
> abstract interface this code doesn't need to know anything about.
>
> Anyway, either way is fine with me.
So I take it that you'll be submitting a fix at least for the parentheses
issue.
Jan
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] Low mem virq incremental adjustments
2012-03-09 9:04 ` Jan Beulich
@ 2012-03-09 9:56 ` Keir Fraser
0 siblings, 0 replies; 6+ messages in thread
From: Keir Fraser @ 2012-03-09 9:56 UTC (permalink / raw)
To: Jan Beulich, andres
Cc: Dan Magenheimer, ian.campbell, andres, tim, xen-devel,
ian.jackson, adin
On 09/03/2012 09:04, "Jan Beulich" <JBeulich@suse.com> wrote:
>>>> On 08.03.12 at 22:59, Dan Magenheimer <dan.magenheimer@oracle.com> wrote:
>>> From: Andres Lagar-Cavilla [mailto:andres@lagarcavilla.org]
>>> Sent: Wednesday, March 07, 2012 11:12 AM
>>> To: Jan Beulich
>>> Cc: Dan Magenheimer; ian.campbell@citrix.com; ian.jackson@citrix.com;
>> adin@gridcentric.ca;
>>> andres@gridcentric.ca; xen-devel; tim@xen.org
>>> Subject: Re: [PATCH] Low mem virq incremental adjustments
>>>
>>>>>>> On 07.03.12 at 17:15, Andres Lagar-Cavilla <andres@lagarcavilla.org>
>>>> wrote:
>>>>> --- a/xen/common/page_alloc.c
>>>>> +++ b/xen/common/page_alloc.c
>>>>> @@ -377,7 +377,10 @@ static void __init setup_low_mem_virq(vo
>>>>>
>>>>> static void check_low_mem_virq(void)
>>>>> {
>>>>> - if ( unlikely(total_avail_pages <= low_mem_virq_th) )
>>>>> + unsigned long avail_pages = total_avail_pages +
>>>>> + (opt_tmem) ? tmem_freeable_pages(): 0;
>>>>
>>>> Can tmem_freeable_pages() return anything other than zero when
>>>> opt_tmem is zero? (I.e. is the [improperly parenthesized!] conditional
>>>> expression necessary at all?)
>>>
>>> I'm not sure. I'll let Dan take it from here, as he surely knows the right
>>> way. He acked it the way it is.
>>> Andres
>>
>> Both would be correct (other than the parentheses).
>>
>> I was also going to make the same comment about tmem_freeable_pages()
>> but decided the way Andres coded it is clearer because it doesn't
>> assume anything about tmem; if tmem is enabled, it uses an
>> abstract interface this code doesn't need to know anything about.
>>
>> Anyway, either way is fine with me.
>
> So I take it that you'll be submitting a fix at least for the parentheses
> issue.
Ugh, I checked it in removing the unnecessary parentheses, but didn't add
the required ones around the ternary operator. I'll fix that now.
-- Keir
> Jan
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 6+ messages in thread
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2012-03-07 16:15 [PATCH] Low mem virq incremental adjustments Andres Lagar-Cavilla
2012-03-07 17:02 ` Jan Beulich
2012-03-07 18:12 ` Andres Lagar-Cavilla
2012-03-08 21:59 ` Dan Magenheimer
2012-03-09 9:04 ` Jan Beulich
2012-03-09 9:56 ` Keir Fraser
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