search for: percpu_ida_cpu

...o relationship with the existing code. Apart from duplicating its functionality :( > > ... > > @@ -243,4 +245,55 @@ static inline int ida_get_new(struct ida *ida, int *p_id) > > void __init idr_init_cache(void); > > +/* Percpu IDA/tag allocator */ > + > +struct percpu_ida_cpu; > + > +struct percpu_ida { > + /* > + * number of tags available to be allocated, as passed to > + * percpu_ida_init() > + */ > + unsigned nr_tags; > + > + struct percpu_ida_cpu __percpu *tag_cpu; > + > + /* > + * Bitmap of cpus that (may) have tags on the...

...o relationship with the existing code. Apart from duplicating its functionality :( > > ... > > @@ -243,4 +245,55 @@ static inline int ida_get_new(struct ida *ida, int *p_id) > > void __init idr_init_cache(void); > > +/* Percpu IDA/tag allocator */ > + > +struct percpu_ida_cpu; > + > +struct percpu_ida { > + /* > + * number of tags available to be allocated, as passed to > + * percpu_ida_init() > + */ > + unsigned nr_tags; > + > + struct percpu_ida_cpu __percpu *tag_cpu; > + > + /* > + * Bitmap of cpus that (may) have tags on the...

...lt;linux/spinlock_types.h> +#include <linux/wait.h> /* * We want shallower trees and thus more bits covered at each layer. 8 @@ -243,4 +245,55 @@ static inline int ida_get_new(struct ida *ida, int *p_id) void __init idr_init_cache(void); +/* Percpu IDA/tag allocator */ + +struct percpu_ida_cpu; + +struct percpu_ida { + /* + * number of tags available to be allocated, as passed to + * percpu_ida_init() + */ + unsigned nr_tags; + + struct percpu_ida_cpu __percpu *tag_cpu; + + /* + * Bitmap of cpus that (may) have tags on their percpu freelists: + * steal_tags() uses this to decide w...

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

...+ unsigned *src, unsigned *src_nr, > + unsigned nr) > +{ > + *src_nr -= nr; > + memcpy(dst + *dst_nr, src + *src_nr, sizeof(unsigned) * nr); > + *dst_nr += nr; > +} > + > +static inline unsigned alloc_local_tag(struct percpu_ida *pool, > + struct percpu_ida_cpu *tags) Pass the __percpu offset and not the tags pointer. > +{ > + int tag = -ENOSPC; > + > + spin_lock(&tags->lock); Interupts are already disabled. Drop the spinlock. > + if (tags->nr_free) > + tag = tags->freelist[--tags->nr_free]; You can keep this or avo...

...+ unsigned *src, unsigned *src_nr, > + unsigned nr) > +{ > + *src_nr -= nr; > + memcpy(dst + *dst_nr, src + *src_nr, sizeof(unsigned) * nr); > + *dst_nr += nr; > +} > + > +static inline unsigned alloc_local_tag(struct percpu_ida *pool, > + struct percpu_ida_cpu *tags) Pass the __percpu offset and not the tags pointer. > +{ > + int tag = -ENOSPC; > + > + spin_lock(&tags->lock); Interupts are already disabled. Drop the spinlock. > + if (tags->nr_free) > + tag = tags->freelist[--tags->nr_free]; You can keep this or avo...

...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 { + /* + * Even though this is percpu, we need a lock for tag stealing by remote + * CPUs: + */ spinlock_t lock; + + /* nr_free/freelist form a stack of free IDs */ unsigned nr_free; unsigned freelist[]; }; @@ -1209,21 +1215,21 @@ static inline void steal_tags(struct percpu_ida *poo...

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

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

...tags - IDA_PCPU_BATCH_MOVE is only used when moving to/from the global freelist. > > > + */ > > +#define IDA_PCPU_BATCH_MOVE 32U > > + > > +/* Max size of percpu freelist, */ > > +#define IDA_PCPU_SIZE ((IDA_PCPU_BATCH_MOVE * 3) / 2) > > + > > +struct percpu_ida_cpu { > > + spinlock_t lock; > > + unsigned nr_free; > > + unsigned freelist[]; > > +}; > > Data structure needs documentation. There's one of these per cpu. I > guess nr_free and freelist are clear enough. The presence of a lock > in a percpu data stru...