From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Jan Beulich <JBeulich@suse.com>
Cc: Ian Campbell <Ian.Campbell@eu.citrix.com>,
xen-devel <xen-devel@lists.xenproject.org>,
Keir Fraser <keir@xen.org>,
Ian Jackson <Ian.Jackson@eu.citrix.com>, Tim Deegan <tim@xen.org>
Subject: Re: [PATCH] switch rangeset's lock to rwlock
Date: Fri, 19 Sep 2014 12:32:02 -0400 [thread overview]
Message-ID: <20140919163202.GA9327@laptop.dumpdata.com> (raw)
In-Reply-To: <5413094B020000780003480E@mail.emea.novell.com>
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.
> 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:[~2014-09-19 16:32 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 [this message]
2014-09-30 8:50 ` Jan Beulich
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
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20140919163202.GA9327@laptop.dumpdata.com \
--to=konrad.wilk@oracle.com \
--cc=Ian.Campbell@eu.citrix.com \
--cc=Ian.Jackson@eu.citrix.com \
--cc=JBeulich@suse.com \
--cc=keir@xen.org \
--cc=tim@xen.org \
--cc=xen-devel@lists.xenproject.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.