diff options
| author | Kent Overstreet <koverstreet@google.com> | 2013-03-02 15:25:50 +1100 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2013-03-07 14:27:19 +1100 |
| commit | fb0c5bcec5ffeaf4c43f8b27594788fe1f03ec22 (patch) | |
| tree | eaa9dd0524d3eee8e723007765a307cd13efd25c /fs | |
| parent | 2b72df4e81ce50cb54b3b67c214f2dabf51c166b (diff) | |
aio: percpu ioctx refcount
This just converts the ioctx refcount to the new generic dynamic percpu
refcount code.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/aio.c | 27 |
1 files changed, 12 insertions, 15 deletions
@@ -36,6 +36,7 @@ #include <linux/eventfd.h> #include <linux/blkdev.h> #include <linux/compat.h> +#include <linux/percpu-refcount.h> #include <asm/kmap_types.h> #include <asm/uaccess.h> @@ -65,8 +66,7 @@ struct kioctx_cpu { }; struct kioctx { - atomic_t users; - atomic_t dead; + struct percpu_ref users; /* This needs improving */ unsigned long user_id; @@ -353,7 +353,7 @@ static void free_ioctx(struct kioctx *ctx) static void put_ioctx(struct kioctx *ctx) { - if (unlikely(atomic_dec_and_test(&ctx->users))) + if (percpu_ref_put(&ctx->users)) free_ioctx(ctx); } @@ -382,8 +382,11 @@ static struct kioctx *ioctx_alloc(unsigned nr_events) ctx->max_reqs = nr_events; - atomic_set(&ctx->users, 2); - atomic_set(&ctx->dead, 0); + percpu_ref_init(&ctx->users); + rcu_read_lock(); + percpu_ref_get(&ctx->users); + rcu_read_unlock(); + spin_lock_init(&ctx->ctx_lock); spin_lock_init(&ctx->completion_lock); mutex_init(&ctx->ring_lock); @@ -455,7 +458,7 @@ static void kill_ioctx_rcu(struct rcu_head *head) */ static void kill_ioctx(struct kioctx *ctx) { - if (!atomic_xchg(&ctx->dead, 1)) { + if (percpu_ref_kill(&ctx->users)) { hlist_del_rcu(&ctx->list); /* Between hlist_del_rcu() and dropping the initial ref */ synchronize_rcu(); @@ -501,12 +504,6 @@ void exit_aio(struct mm_struct *mm) struct hlist_node *n; hlist_for_each_entry_safe(ctx, n, &mm->ioctx_list, list) { - if (1 != atomic_read(&ctx->users)) - printk(KERN_DEBUG - "exit_aio:ioctx still alive: %d %d %d\n", - atomic_read(&ctx->users), - atomic_read(&ctx->dead), - atomic_read(&ctx->reqs_available)); /* * We don't need to bother with munmap() here - * exit_mmap(mm) is coming and it'll unmap everything. @@ -517,7 +514,7 @@ void exit_aio(struct mm_struct *mm) */ ctx->mmap_size = 0; - if (!atomic_xchg(&ctx->dead, 1)) { + if (percpu_ref_kill(&ctx->users)) { hlist_del_rcu(&ctx->list); call_rcu(&ctx->rcu_head, kill_ioctx_rcu); } @@ -628,7 +625,7 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id) hlist_for_each_entry_rcu(ctx, &mm->ioctx_list, list) { if (ctx->user_id == ctx_id){ - atomic_inc(&ctx->users); + percpu_ref_get(&ctx->users); ret = ctx; break; } @@ -843,7 +840,7 @@ static bool aio_read_events(struct kioctx *ctx, long min_nr, long nr, if (ret > 0) *i += ret; - if (unlikely(atomic_read(&ctx->dead))) + if (unlikely(percpu_ref_dead(&ctx->users))) ret = -EINVAL; if (!*i) |