search for: cpus_have_tags

...t a/include/linux/idr.h b/include/linux/idr.h index f0db12b..cdf39be 100644 --- a/include/linux/idr.h +++ b/include/linux/idr.h @@ -267,7 +267,7 @@ struct percpu_ida { * will just keep looking - but the bitmap _must_ be set whenever a * percpu freelist does have tags. */ - unsigned long *cpus_have_tags; + cpumask_t cpus_have_tags; struct { spinlock_t lock; diff --git a/lib/idr.c b/lib/idr.c index 26495e1..15c021c 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -1178,7 +1178,13 @@ EXPORT_SYMBOL(ida_init); #define IDA_PCPU_SIZE ((IDA_PCPU_BATCH_MOVE * 3) / 2) struct percpu_ida_cpu { + /* +...

...tags, and which cpus > + * to try stealing from. > + * > + * It's ok for a freelist to be empty when its bit is set - steal_tags() > + * will just keep looking - but the bitmap _must_ be set whenever a > + * percpu freelist does have tags. > + */ > + unsigned long *cpus_have_tags; Why not cpumask_t? > + struct { > + spinlock_t lock; > + /* > + * When we go to steal tags from another cpu (see steal_tags()), > + * we want to pick a cpu at random. Cycling through them every > + * time we steal is a bit easier and more or less equivalent: > + *...

...tags, and which cpus > + * to try stealing from. > + * > + * It's ok for a freelist to be empty when its bit is set - steal_tags() > + * will just keep looking - but the bitmap _must_ be set whenever a > + * percpu freelist does have tags. > + */ > + unsigned long *cpus_have_tags; Why not cpumask_t? > + struct { > + spinlock_t lock; > + /* > + * When we go to steal tags from another cpu (see steal_tags()), > + * we want to pick a cpu at random. Cycling through them every > + * time we steal is a bit easier and more or less equivalent: > + *...

...) uses this to decide when to steal tags, and which cpus + * to try stealing from. + * + * It's ok for a freelist to be empty when its bit is set - steal_tags() + * will just keep looking - but the bitmap _must_ be set whenever a + * percpu freelist does have tags. + */ + unsigned long *cpus_have_tags; + + struct { + spinlock_t lock; + /* + * When we go to steal tags from another cpu (see steal_tags()), + * we want to pick a cpu at random. Cycling through them every + * time we steal is a bit easier and more or less equivalent: + */ + unsigned cpu_last_stolen; + + /* For sleeping o...

From: Nicholas Bellinger <nab at linux-iscsi.org> Hi folks, This is an updated series for adding tag pre-allocation support of target fabric descriptor memory, utilizing Kent's latest per-cpu ida bits here, along with Christoph Lameter's latest comments: [PATCH 04/10] idr: Percpu ida http://marc.info/?l=linux-kernel&m=137160026006974&w=2 The first patch is a

From: Nicholas Bellinger <nab at linux-iscsi.org> Hi folks, This is an updated series for adding tag pre-allocation support of target fabric descriptor memory, utilizing Kent's latest per-cpu ida bits here, along with Christoph Lameter's latest comments: [PATCH 04/10] idr: Percpu ida http://marc.info/?l=linux-kernel&m=137160026006974&w=2 The first patch is a

...com> wrote: > > > + while (1) { > > > + spin_lock(&pool->lock); > > > + > > > + /* > > > + * prepare_to_wait() must come before steal_tags(), in case > > > + * percpu_ida_free() on another cpu flips a bit in > > > + * cpus_have_tags > > > + * > > > + * global lock held and irqs disabled, don't need percpu lock > > > + */ > > > + prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE); > > > + > > > + if (!tags->nr_free) > > > + alloc_g...

...com> wrote: > > > + while (1) { > > > + spin_lock(&pool->lock); > > > + > > > + /* > > > + * prepare_to_wait() must come before steal_tags(), in case > > > + * percpu_ida_free() on another cpu flips a bit in > > > + * cpus_have_tags > > > + * > > > + * global lock held and irqs disabled, don't need percpu lock > > > + */ > > > + prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE); > > > + > > > + if (!tags->nr_free) > > > + alloc_g...

Removing the percpu_ida code nets over 400 lines of removal. It's not as spectacular as deleting an entire architecture, but it's still a worthy reduction in lines of code. Untested due to lack of hardware and not understanding how to set up a target platform. Changes from v1: - Fixed bugs pointed out by Jens in iscsit_wait_for_tag() - Abstracted out tag freeing as requested by Bart

Removing the percpu_ida code nets over 400 lines of removal. It's not as spectacular as deleting an entire architecture, but it's still a worthy reduction in lines of code. Untested due to lack of hardware and not understanding how to set up a target platform. Changes from v1: - Fixed bugs pointed out by Jens in iscsit_wait_for_tag() - Abstracted out tag freeing as requested by Bart

From: Matthew Wilcox <mawilcox at microsoft.com> This is a pretty rough-and-ready conversion of the target drivers from using percpu_ida to sbitmap. It compiles; I don't have a target setup, so it's completely untested. I haven't tried to do anything particularly clever here, so it's possible that, for example, the wait queue in iscsi_target_util could be more clever, like

...* to try stealing from. > > + * > > + * It's ok for a freelist to be empty when its bit is set - steal_tags() > > + * will just keep looking - but the bitmap _must_ be set whenever a > > + * percpu freelist does have tags. > > + */ > > + unsigned long *cpus_have_tags; > > Why not cpumask_t? I hadn't encountered it before - looks like it's probably what I want. I don't see any explanation for the parallel set of operations for working on cpumasks - e.g. next_cpu()/cpumask_next(). For now I'm going with the cpumask_* versions, is that wha...

...+ while (1) { > > > > + spin_lock(&pool->lock); > > > > + > > > > + /* > > > > + * prepare_to_wait() must come before steal_tags(), in case > > > > + * percpu_ida_free() on another cpu flips a bit in > > > > + * cpus_have_tags > > > > + * > > > > + * global lock held and irqs disabled, don't need percpu lock > > > > + */ > > > > + prepare_to_wait(&pool->wait, &wait, TASK_UNINTERRUPTIBLE); > > > > + > > > > + if (!tags->nr_fr...