From: Vincent Fu <Vincent.Fu@xxxxxxx> The Linux sg driver accepts only 16 SCSI commands in flight at a time per file descriptor. fio does not exit gracefully when it attempts to queue up 17 or more trim commands via the sg ioengine. This patch improves error handling in the sg ioengine commit function to achieve a graceful exit if fio attempts to queue up too many trim commands. The key to this is calling clear_io_u on each io_u in the 17th trim command. With this patch fio no longer loops forever waiting for the IOs in the (not succesffully submitted) 17th trim command to complete. --- engines/sg.c | 49 +++++++++++++++++++++++++------------------------ 1 file changed, 25 insertions(+), 24 deletions(-) diff --git a/engines/sg.c b/engines/sg.c index 7741f83..3cc068f 100644 --- a/engines/sg.c +++ b/engines/sg.c @@ -675,36 +675,37 @@ static int fio_sgio_commit(struct thread_data *td) ret = fio_sgio_rw_doio(io_u->file, io_u, 0); - if (ret < 0) - for (i = 0; i < st->unmap_range_count; i++) - st->trim_io_us[i]->error = errno; - else if (hdr->status) - for (i = 0; i < st->unmap_range_count; i++) { - st->trim_io_us[i]->resid = hdr->resid; - st->trim_io_us[i]->error = EIO; + if (ret < 0 || hdr->status) { + int error; + + if (ret < 0) + error = errno; + else { + error = EIO; + ret = -EIO; } - else { - if (fio_fill_issue_time(td)) { - fio_gettime(&now, NULL); - for (i = 0; i < st->unmap_range_count; i++) { - struct io_u *io_u = st->trim_io_us[i]; - - memcpy(&io_u->issue_time, &now, sizeof(now)); - io_u_queued(td, io_u); - } + + for (i = 0; i < st->unmap_range_count; i++) { + st->trim_io_us[i]->error = error; + clear_io_u(td, st->trim_io_us[i]); + if (hdr->status) + st->trim_io_us[i]->resid = hdr->resid; } - io_u_mark_submit(td, st->unmap_range_count); + + td_verror(td, error, "xfer"); + return ret; } - if (io_u->error) { - td_verror(td, io_u->error, "xfer"); - return 0; + if (fio_fill_issue_time(td)) { + fio_gettime(&now, NULL); + for (i = 0; i < st->unmap_range_count; i++) { + memcpy(&st->trim_io_us[i]->issue_time, &now, sizeof(now)); + io_u_queued(td, io_u); + } } + io_u_mark_submit(td, st->unmap_range_count); - if (ret == FIO_Q_QUEUED) - return 0; - else - return ret; + return 0; } static struct io_u *fio_sgio_event(struct thread_data *td, int event) -- 2.7.4