From: "Jan Beulich" <JBeulich@suse.com>
To: Ian Campbell <Ian.Campbell@eu.citrix.com>,
Ian Jackson <Ian.Jackson@eu.citrix.com>,
Keir Fraser <keir@xen.org>, Tim Deegan <tim@xen.org>
Cc: xen-devel <xen-devel@lists.xenproject.org>
Subject: Re: [PATCH] switch rangeset's lock to rwlock
Date: Tue, 30 Sep 2014 09:50:05 +0100 [thread overview]
Message-ID: <542A8ADD020000780003AE5E@mail.emea.novell.com> (raw)
In-Reply-To: <20140919163202.GA9327@laptop.dumpdata.com>
>>> On 19.09.14 at 18:32, <konrad.wilk@oracle.com> wrote:
> On Fri, Sep 12, 2014 at 01:55:07PM +0100, Jan Beulich wrote:
>> As a general library routine, it should behave as efficiently as
>> possible, even if at present no significant contention is known here.
>>
>
> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
>
> I am comfortable with this going to Xen 4.5.
Anyone of you wanting to ack this then, or should I nevertheless
postpone it until after 4.5?
Jan
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> ---
>> With the widened use of rangesets I'd like to re-suggest this change
>> which I had posted already a couple of years back.
>>
>> --- a/xen/common/rangeset.c
>> +++ b/xen/common/rangeset.c
>> @@ -28,7 +28,7 @@ struct rangeset {
>>
>> /* Number of ranges that can be allocated */
>> long nr_ranges;
>> - spinlock_t lock;
>> + rwlock_t lock;
>>
>> /* Pretty-printing name. */
>> char name[32];
>> @@ -120,7 +120,7 @@ int rangeset_add_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + write_lock(&r->lock);
>>
>> x = find_range(r, s);
>> y = find_range(r, e);
>> @@ -176,7 +176,7 @@ int rangeset_add_range(
>> }
>>
>> out:
>> - spin_unlock(&r->lock);
>> + write_unlock(&r->lock);
>> return rc;
>> }
>>
>> @@ -188,7 +188,7 @@ int rangeset_remove_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + write_lock(&r->lock);
>>
>> x = find_range(r, s);
>> y = find_range(r, e);
>> @@ -244,7 +244,7 @@ int rangeset_remove_range(
>> }
>>
>> out:
>> - spin_unlock(&r->lock);
>> + write_unlock(&r->lock);
>> return rc;
>> }
>>
>> @@ -256,10 +256,10 @@ int rangeset_contains_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>> x = find_range(r, s);
>> contains = (x && (x->e >= e));
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>>
>> return contains;
>> }
>> @@ -272,10 +272,10 @@ int rangeset_overlaps_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>> x = find_range(r, e);
>> overlaps = (x && (s <= x->e));
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>>
>> return overlaps;
>> }
>> @@ -287,13 +287,13 @@ int rangeset_report_ranges(
>> struct range *x;
>> int rc = 0;
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>>
>> for ( x = find_range(r, s); x && (x->s <= e) && !rc; x = next_range(r, x) )
>> if ( x->e >= s )
>> rc = cb(max(x->s, s), min(x->e, e), ctxt);
>>
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>>
>> return rc;
>> }
>> @@ -331,7 +331,7 @@ struct rangeset *rangeset_new(
>> if ( r == NULL )
>> return NULL;
>>
>> - spin_lock_init(&r->lock);
>> + rwlock_init(&r->lock);
>> INIT_LIST_HEAD(&r->range_list);
>> r->nr_ranges = -1;
>>
>> @@ -414,21 +414,21 @@ void rangeset_swap(struct rangeset *a, s
>>
>> if ( a < b )
>> {
>> - spin_lock(&a->lock);
>> - spin_lock(&b->lock);
>> + write_lock(&a->lock);
>> + write_lock(&b->lock);
>> }
>> else
>> {
>> - spin_lock(&b->lock);
>> - spin_lock(&a->lock);
>> + write_lock(&b->lock);
>> + write_lock(&a->lock);
>> }
>>
>> list_splice_init(&a->range_list, &tmp);
>> list_splice_init(&b->range_list, &a->range_list);
>> list_splice(&tmp, &b->range_list);
>>
>> - spin_unlock(&a->lock);
>> - spin_unlock(&b->lock);
>> + write_unlock(&a->lock);
>> + write_unlock(&b->lock);
>> }
>>
>> /*****************************
>> @@ -446,7 +446,7 @@ void rangeset_printk(
>> int nr_printed = 0;
>> struct range *x;
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>>
>> printk("%-10s {", r->name);
>>
>> @@ -465,7 +465,7 @@ void rangeset_printk(
>>
>> printk(" }");
>>
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>> }
>>
>> void rangeset_domain_printk(
>>
>>
>>
>
>> switch rangeset's lock to rwlock
>>
>> As a general library routine, it should behave as efficiently as
>> possible, even if at present no significant contention is known here.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> ---
>> With the widened use of rangesets I'd like to re-suggest this change
>> which I had posted already a couple of years back.
>>
>> --- a/xen/common/rangeset.c
>> +++ b/xen/common/rangeset.c
>> @@ -28,7 +28,7 @@ struct rangeset {
>>
>> /* Number of ranges that can be allocated */
>> long nr_ranges;
>> - spinlock_t lock;
>> + rwlock_t lock;
>>
>> /* Pretty-printing name. */
>> char name[32];
>> @@ -120,7 +120,7 @@ int rangeset_add_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + write_lock(&r->lock);
>>
>> x = find_range(r, s);
>> y = find_range(r, e);
>> @@ -176,7 +176,7 @@ int rangeset_add_range(
>> }
>>
>> out:
>> - spin_unlock(&r->lock);
>> + write_unlock(&r->lock);
>> return rc;
>> }
>>
>> @@ -188,7 +188,7 @@ int rangeset_remove_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + write_lock(&r->lock);
>>
>> x = find_range(r, s);
>> y = find_range(r, e);
>> @@ -244,7 +244,7 @@ int rangeset_remove_range(
>> }
>>
>> out:
>> - spin_unlock(&r->lock);
>> + write_unlock(&r->lock);
>> return rc;
>> }
>>
>> @@ -256,10 +256,10 @@ int rangeset_contains_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>> x = find_range(r, s);
>> contains = (x && (x->e >= e));
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>>
>> return contains;
>> }
>> @@ -272,10 +272,10 @@ int rangeset_overlaps_range(
>>
>> ASSERT(s <= e);
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>> x = find_range(r, e);
>> overlaps = (x && (s <= x->e));
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>>
>> return overlaps;
>> }
>> @@ -287,13 +287,13 @@ int rangeset_report_ranges(
>> struct range *x;
>> int rc = 0;
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>>
>> for ( x = find_range(r, s); x && (x->s <= e) && !rc; x = next_range(r, x) )
>> if ( x->e >= s )
>> rc = cb(max(x->s, s), min(x->e, e), ctxt);
>>
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>>
>> return rc;
>> }
>> @@ -331,7 +331,7 @@ struct rangeset *rangeset_new(
>> if ( r == NULL )
>> return NULL;
>>
>> - spin_lock_init(&r->lock);
>> + rwlock_init(&r->lock);
>> INIT_LIST_HEAD(&r->range_list);
>> r->nr_ranges = -1;
>>
>> @@ -414,21 +414,21 @@ void rangeset_swap(struct rangeset *a, s
>>
>> if ( a < b )
>> {
>> - spin_lock(&a->lock);
>> - spin_lock(&b->lock);
>> + write_lock(&a->lock);
>> + write_lock(&b->lock);
>> }
>> else
>> {
>> - spin_lock(&b->lock);
>> - spin_lock(&a->lock);
>> + write_lock(&b->lock);
>> + write_lock(&a->lock);
>> }
>>
>> list_splice_init(&a->range_list, &tmp);
>> list_splice_init(&b->range_list, &a->range_list);
>> list_splice(&tmp, &b->range_list);
>>
>> - spin_unlock(&a->lock);
>> - spin_unlock(&b->lock);
>> + write_unlock(&a->lock);
>> + write_unlock(&b->lock);
>> }
>>
>> /*****************************
>> @@ -446,7 +446,7 @@ void rangeset_printk(
>> int nr_printed = 0;
>> struct range *x;
>>
>> - spin_lock(&r->lock);
>> + read_lock(&r->lock);
>>
>> printk("%-10s {", r->name);
>>
>> @@ -465,7 +465,7 @@ void rangeset_printk(
>>
>> printk(" }");
>>
>> - spin_unlock(&r->lock);
>> + read_unlock(&r->lock);
>> }
>>
>> void rangeset_domain_printk(
>
>> _______________________________________________
>> Xen-devel mailing list
>> Xen-devel@lists.xen.org
>> http://lists.xen.org/xen-devel
next prev parent reply other threads:[~2014-09-30 8:50 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-12 12:55 [PATCH] switch rangeset's lock to rwlock Jan Beulich
2014-09-18 10:43 ` Tim Deegan
2014-09-18 12:15 ` Jan Beulich
2014-09-18 13:02 ` Tim Deegan
2014-09-18 13:32 ` Jan Beulich
2014-09-18 14:52 ` Paul Durrant
2014-09-19 16:33 ` Konrad Rzeszutek Wilk
2014-09-22 9:42 ` Ian Campbell
2014-09-22 10:34 ` Jan Beulich
2014-09-19 16:32 ` Konrad Rzeszutek Wilk
2014-09-30 8:50 ` Jan Beulich [this message]
2014-09-30 12:01 ` Tim Deegan
2014-09-30 20:53 ` Keir Fraser
2014-10-01 8:57 ` Jan Beulich
2014-10-01 9:31 ` Keir Fraser
-- strict thread matches above, loose matches on Subject: below --
2011-03-25 16:49 Jan Beulich
2011-03-25 17:08 ` Keir Fraser
2011-03-25 17:52 ` Dan Magenheimer
2011-03-25 20:52 ` Keir Fraser
2011-03-30 22:44 ` Jeremy Fitzhardinge
2011-03-28 8:23 ` Jan Beulich
2011-03-28 8:54 ` Keir Fraser
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