libaio,io_uring: relax cmdprio_percentage constraints

[fio.git] / engines / io_uring.c

diff --git a/engines/io_uring.c b/engines/io_uring.c
index 57124d226ad01f6dbbbc8cc23103275cb6307523..df2d6c4c7e4a1e3903b4446974dd70abd8700025 100644 (file)
--- a/engines/io_uring.c
+++ b/engines/io_uring.c
@@ -65,8 +65,6 @@ struct ioring_data {
        int queued;
        int cq_ring_off;
        unsigned iodepth;
-       bool ioprio_class_set;
-       bool ioprio_set;
        int prepped;
 
        struct ioring_mmap mmap[3];
@@ -340,10 +338,6 @@ static int fio_ioring_prep(struct thread_data *td, struct io_u *io_u)
                        sqe->rw_flags |= RWF_UNCACHED;
                if (o->nowait)
                        sqe->rw_flags |= RWF_NOWAIT;
-               if (ld->ioprio_class_set)
-                       sqe->ioprio = td->o.ioprio_class << 13;
-               if (ld->ioprio_set)
-                       sqe->ioprio |= td->o.ioprio;
                sqe->off = io_u->offset;
        } else if (ddir_sync(io_u->ddir)) {
                sqe->ioprio = 0;
@@ -458,13 +452,30 @@ static void fio_ioring_prio_prep(struct thread_data *td, struct io_u *io_u)
        struct cmdprio *cmdprio = &o->cmdprio;
        enum fio_ddir ddir = io_u->ddir;
        unsigned int p = fio_cmdprio_percentage(cmdprio, io_u);
+       unsigned int cmdprio_value =
+               ioprio_value(cmdprio->class[ddir], cmdprio->level[ddir]);
 
        if (p && rand_between(&td->prio_state, 0, 99) < p) {
-               sqe->ioprio =
-                       ioprio_value(cmdprio->class[ddir], cmdprio->level[ddir]);
-               io_u->flags |= IO_U_F_PRIORITY;
+               sqe->ioprio = cmdprio_value;
+               if (!td->ioprio || cmdprio_value < td->ioprio) {
+                       /*
+                        * The async IO priority is higher (has a lower value)
+                        * than the priority set by "prio" and "prioclass"
+                        * options.
+                        */
+                       io_u->flags |= IO_U_F_PRIORITY;
+               }
        } else {
-               sqe->ioprio = 0;
+               sqe->ioprio = td->ioprio;
+               if (cmdprio_value && td->ioprio && td->ioprio < cmdprio_value) {
+                       /*
+                        * The IO will be executed with the priority set by
+                        * "prio" and "prioclass" options, and this priority
+                        * is higher (has a lower value) than the async IO
+                        * priority.
+                        */
+                       io_u->flags |= IO_U_F_PRIORITY;
+               }
        }
 }
 
@@ -807,6 +818,7 @@ static int fio_ioring_init(struct thread_data *td)
        struct ioring_options *o = td->eo;
        struct ioring_data *ld;
        struct cmdprio *cmdprio = &o->cmdprio;
+       bool has_cmdprio = false;
        int ret;
 
        /* sqthread submission requires registered files */
@@ -831,16 +843,21 @@ static int fio_ioring_init(struct thread_data *td)
 
        td->io_ops_data = ld;
 
-       ret = fio_cmdprio_init(td, cmdprio, &ld->use_cmdprio);
+       ret = fio_cmdprio_init(td, cmdprio, &has_cmdprio);
        if (ret) {
                td_verror(td, EINVAL, "fio_ioring_init");
                return 1;
        }
 
-       if (fio_option_is_set(&td->o, ioprio_class))
-               ld->ioprio_class_set = true;
-       if (fio_option_is_set(&td->o, ioprio))
-               ld->ioprio_set = true;
+       /*
+        * Since io_uring can have a submission context (sqthread_poll) that is
+        * different from the process context, we cannot rely on the the IO
+        * priority set by ioprio_set() (option prio/prioclass) to be inherited.
+        * Therefore, we set the sqe->ioprio field when prio/prioclass is used.
+        */
+       ld->use_cmdprio = has_cmdprio ||
+               fio_option_is_set(&td->o, ioprio_class) ||
+               fio_option_is_set(&td->o, ioprio);
 
        return 0;
 }