Author: imp
Date: Thu Feb 22 05:43:50 2018
New Revision: 329814
URL: https://svnweb.freebsd.org/changeset/base/329814
Log:
Note when we tick.
To help implement a policy of 'queue all trims until next I/O sched
tick' policy to help coalesce them, note when we tick so we can do
something special on the first call after the tick to get more work.
Sponsored by: Netflix
Modified:
head/sys/cam/cam_iosched.c
Modified: head/sys/cam/cam_iosched.c
==============================================================================
--- head/sys/cam/cam_iosched.c Thu Feb 22 05:43:45 2018 (r329813)
+++ head/sys/cam/cam_iosched.c Thu Feb 22 05:43:50 2018 (r329814)
@@ -60,6 +60,19 @@ static MALLOC_DEFINE(M_CAMSCHED, "CAM I/O Scheduler",
"CAM I/O Scheduler buffers");
/*
+ * Trim or similar currently pending completion. Should only be set for
+ * those drivers wishing only one Trim active at a time.
+ */
+#define CAM_IOSCHED_FLAG_TRIM_ACTIVE (1ul << 0)
+ /* Callout active, and needs to be torn down */
+#define CAM_IOSCHED_FLAG_CALLOUT_ACTIVE (1ul << 1)
+ /* Timer has just ticked */
+#define CAM_IOSCHED_FLAG_TICK (1ul << 2)
+
+ /* Periph drivers set these flags to indicate work */
+#define CAM_IOSCHED_FLAG_WORK_FLAGS ((0xffffu) << 16)
+
+/*
* Default I/O scheduler for FreeBSD. This implementation is just a thin-vineer
* over the bioq_* interface, with notions of separate calls for normal I/O and
* for trims.
@@ -574,6 +587,7 @@ cam_iosched_ticker(void *arg)
cam_iosched_limiter_tick(&isc->write_stats);
cam_iosched_limiter_tick(&isc->trim_stats);
+ isc->flags |= CAM_IOSCHED_FLAGS_TICK;
cam_iosched_schedule(isc, isc->periph);
/*
@@ -701,17 +715,6 @@ cam_iosched_cl_maybe_steer(struct control_loop *clp)
}
#endif
-/*
- * Trim or similar currently pending completion. Should only be set for
- * those drivers wishing only one Trim active at a time.
- */
-#define CAM_IOSCHED_FLAG_TRIM_ACTIVE (1ul << 0)
- /* Callout active, and needs to be torn down */
-#define CAM_IOSCHED_FLAG_CALLOUT_ACTIVE (1ul << 1)
-
- /* Periph drivers set these flags to indicate work */
-#define CAM_IOSCHED_FLAG_WORK_FLAGS ((0xffffu) << 16)
-
#ifdef CAM_IOSCHED_DYNAMIC
static void
cam_iosched_io_metric_update(struct cam_iosched_softc *isc,
@@ -1322,6 +1325,10 @@ struct bio *
cam_iosched_next_bio(struct cam_iosched_softc *isc)
{
struct bio *bp;
+ bool wastick;
+
+ wastick = !!(isc->flags & CAM_IOSCHED_FLAGS_TICK);
+ isc->flags &= ~CAM_IOSCHED_FLAGS_TICK;
/*
* See if we have a trim that can be scheduled. We can only send one
_______________________________________________
svn-src-all@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
