diff options
| author | Eric Paris <eparis@redhat.com> | 2013-11-22 18:57:08 -0500 |
|---|---|---|
| committer | Eric Paris <eparis@redhat.com> | 2013-11-22 18:57:54 -0500 |
| commit | fc582aef7dcc27a7120cf232c1e76c569c7b6eab (patch) | |
| tree | 7d275dd4ceab6067b91e9a25a5f6338b425fbccd /include/linux/percpu_ida.h | |
| parent | 9175c9d2aed528800175ef81c90569d00d23f9be (diff) | |
| parent | 5e01dc7b26d9f24f39abace5da98ccbd6a5ceb52 (diff) | |
Merge tag 'v3.12'
Linux 3.12
Conflicts:
fs/exec.c
Diffstat (limited to 'include/linux/percpu_ida.h')
| -rw-r--r-- | include/linux/percpu_ida.h | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/include/linux/percpu_ida.h b/include/linux/percpu_ida.h new file mode 100644 index 000000000000..0b23edbee309 --- /dev/null +++ b/include/linux/percpu_ida.h | |||
| @@ -0,0 +1,60 @@ | |||
| 1 | #ifndef __PERCPU_IDA_H__ | ||
| 2 | #define __PERCPU_IDA_H__ | ||
| 3 | |||
| 4 | #include <linux/types.h> | ||
| 5 | #include <linux/bitops.h> | ||
| 6 | #include <linux/init.h> | ||
| 7 | #include <linux/spinlock_types.h> | ||
| 8 | #include <linux/wait.h> | ||
| 9 | #include <linux/cpumask.h> | ||
| 10 | |||
| 11 | struct percpu_ida_cpu; | ||
| 12 | |||
| 13 | struct percpu_ida { | ||
| 14 | /* | ||
| 15 | * number of tags available to be allocated, as passed to | ||
| 16 | * percpu_ida_init() | ||
| 17 | */ | ||
| 18 | unsigned nr_tags; | ||
| 19 | |||
| 20 | struct percpu_ida_cpu __percpu *tag_cpu; | ||
| 21 | |||
| 22 | /* | ||
| 23 | * Bitmap of cpus that (may) have tags on their percpu freelists: | ||
| 24 | * steal_tags() uses this to decide when to steal tags, and which cpus | ||
| 25 | * to try stealing from. | ||
| 26 | * | ||
| 27 | * It's ok for a freelist to be empty when its bit is set - steal_tags() | ||
| 28 | * will just keep looking - but the bitmap _must_ be set whenever a | ||
| 29 | * percpu freelist does have tags. | ||
| 30 | */ | ||
| 31 | cpumask_t cpus_have_tags; | ||
| 32 | |||
| 33 | struct { | ||
| 34 | spinlock_t lock; | ||
| 35 | /* | ||
| 36 | * When we go to steal tags from another cpu (see steal_tags()), | ||
| 37 | * we want to pick a cpu at random. Cycling through them every | ||
| 38 | * time we steal is a bit easier and more or less equivalent: | ||
| 39 | */ | ||
| 40 | unsigned cpu_last_stolen; | ||
| 41 | |||
| 42 | /* For sleeping on allocation failure */ | ||
| 43 | wait_queue_head_t wait; | ||
| 44 | |||
| 45 | /* | ||
| 46 | * Global freelist - it's a stack where nr_free points to the | ||
| 47 | * top | ||
| 48 | */ | ||
| 49 | unsigned nr_free; | ||
| 50 | unsigned *freelist; | ||
| 51 | } ____cacheline_aligned_in_smp; | ||
| 52 | }; | ||
| 53 | |||
| 54 | int percpu_ida_alloc(struct percpu_ida *pool, gfp_t gfp); | ||
| 55 | void percpu_ida_free(struct percpu_ida *pool, unsigned tag); | ||
| 56 | |||
| 57 | void percpu_ida_destroy(struct percpu_ida *pool); | ||
| 58 | int percpu_ida_init(struct percpu_ida *pool, unsigned long nr_tags); | ||
| 59 | |||
| 60 | #endif /* __PERCPU_IDA_H__ */ | ||
