On 11/9/21 17:36, Douglas Gilbert wrote:
On 2021-11-09 7:44 p.m., Bart Van Assche wrote:
The time spent in io_schedule() is significant when submitting direct
I/O to a UFS device. Hence this patch that implements polling support.
User space software can enable polling by passing the RWF_HIPRI flag to
the preadv2() system call or the IORING_SETUP_IOPOLL flag to the
io_uring interface.
There have been some changes recently (i.e. in linux-stable now),
"HIPRI" seems to be on the out, replaced by "POLLED". [I'm using
poll_lld in my sg rewrite to refer to this type of polling, as "poll"
is an overloaded term in the kernel].
REQ_HIPRI has become REQ_POLLED and blk_poll() is now bio_poll().
That said RWF_HIPRI is still in fs.h and there is no RWF_POLLED (yet).
Hi Doug,
My reference to RWF_HIPRI in the patch description refers to the flag
defined in the uapi headers. As far as I know that flag is still there:
$ PAGER= git grep define.RWF_HIPRI include/uapi
include/uapi/linux/fs.h:#define RWF_HIPRI ((__force __kernel_rwf_t)0x00000001)
Thanks,
Bart.
