Re: [PATCH v3 1/4] fsstress: add IO_URING read and write operations

Jens Axboe
2020-09-03T14:58:49Z

On 9/3/20 6:42 AM, Brian Foster wrote:
> On Sun, Aug 23, 2020 at 02:30:29PM +0800, Zorro Lang wrote:
>> IO_URING is a new feature of curent linux kernel, add basic IO_URING
>> read/write into fsstess to cover this kind of IO testing.
>>
>> Signed-off-by: Zorro Lang <zlang@redhat.com>
>> ---
>> README | 4 +-
>> configure.ac | 1 +
>> include/builddefs.in | 1 +
>> ltp/Makefile | 5 ++
>> ltp/fsstress.c | 139 ++++++++++++++++++++++++++++++++++++++++-
>> m4/Makefile | 1 +
>> m4/package_liburing.m4 | 4 ++
>> 7 files changed, 152 insertions(+), 3 deletions(-)
>> create mode 100644 m4/package_liburing.m4
>>
> ...
>> diff --git a/ltp/fsstress.c b/ltp/fsstress.c
>> index 709fdeec..7a0e278a 100644
>> --- a/ltp/fsstress.c
>> +++ b/ltp/fsstress.c
> ...
>> @@ -2170,6 +2189,108 @@ do_aio_rw(int opno, long r, int flags)
>> }
>> #endif
>>
>> +#ifdef URING
>> +void
>> +do_uring_rw(int opno, long r, int flags)
>> +{
>> + char *buf;
>> + int e;
>> + pathname_t f;
>> + int fd;
>> + size_t len;
>> + int64_t lr;
>> + off64_t off;
>> + struct stat64 stb;
>> + int v;
>> + char st[1024];
>> + struct io_uring_sqe *sqe;
>> + struct io_uring_cqe *cqe;
>> + struct iovec iovec;
>> + int iswrite = (flags & (O_WRONLY | O_RDWR)) ? 1 : 0;
>> +
>> + init_pathname(&f);
>> + if (!get_fname(FT_REGFILE, r, &f, NULL, NULL, &v)) {
>> + if (v)
>> + printf("%d/%d: do_uring_rw - no filename\n", procid, opno);
>> + goto uring_out3;
>> + }
>> + fd = open_path(&f, flags);
>> + e = fd < 0 ? errno : 0;
>> + check_cwd();
>> + if (fd < 0) {
>> + if (v)
>> + printf("%d/%d: do_uring_rw - open %s failed %d\n",
>> + procid, opno, f.path, e);
>> + goto uring_out3;
>> + }
>> + if (fstat64(fd, &stb) < 0) {
>> + if (v)
>> + printf("%d/%d: do_uring_rw - fstat64 %s failed %d\n",
>> + procid, opno, f.path, errno);
>> + goto uring_out2;
>> + }
>> + inode_info(st, sizeof(st), &stb, v);
>> + if (!iswrite && stb.st_size == 0) {
>> + if (v)
>> + printf("%d/%d: do_uring_rw - %s%s zero size\n", procid, opno,
>> + f.path, st);
>> + goto uring_out2;
>> + }
>> + sqe = io_uring_get_sqe(&ring);
>> + if (!sqe) {
>> + if (v)
>> + printf("%d/%d: do_uring_rw - io_uring_get_sqe failed\n",
>> + procid, opno);
>> + goto uring_out2;
>> + }
>
> I'm not familiar with the io_uring bits, but do we have to do anything
> to clean up this sqe object (or the cqe) before we return?

The cqe/sqe resources are tied to the ring, so as long as
io_uring_queue_exit() is called, then they are freed. And it is after
the run, so looks fine to me.

--
Jens Axboe