Jens Axboe <axboe@xxxxxxxxx> writes:
> It's 192 bytes, fairly substantial. Most items don't need to be cleared,
> especially not upfront. Clear the ones we do need to clear, and leave
> the other ones for setup when the iocb is prepared and submitted.
What performance gains do you see from this?
-Jeff
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> ---
> fs/aio.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/fs/aio.c b/fs/aio.c
> index eaceb40e6cf5..522c04864d82 100644
> --- a/fs/aio.c
> +++ b/fs/aio.c
> @@ -1009,14 +1009,15 @@ static inline struct aio_kiocb *aio_get_req(struct kioctx *ctx)
> {
> struct aio_kiocb *req;
>
> - req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL|__GFP_ZERO);
> + req = kmem_cache_alloc(kiocb_cachep, GFP_KERNEL);
> if (unlikely(!req))
> return NULL;
>
> percpu_ref_get(&ctx->reqs);
> + req->ki_ctx = ctx;
> INIT_LIST_HEAD(&req->ki_list);
> refcount_set(&req->ki_refcnt, 0);
> - req->ki_ctx = ctx;
> + req->ki_eventfd = NULL;
> return req;
> }
>
> @@ -1730,6 +1731,10 @@ static ssize_t aio_poll(struct aio_kiocb *aiocb, struct iocb *iocb)
> if (unlikely(!req->file))
> return -EBADF;
>
> + req->head = NULL;
> + req->woken = false;
> + req->cancelled = false;
> +
> apt.pt._qproc = aio_poll_queue_proc;
> apt.pt._key = req->events;
> apt.iocb = aiocb;
