Re-consolidate zio_delay_interrupt

With recent SPL changes there is no longer any need for a per platform version. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Matt Macy <mmacy@FreeBSD.org> Closes #9860
openzfs · Jan 21, 2020 · d3c1e45 · d3c1e45
1 parent 09436c5
commit d3c1e45
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Showing 4 changed files with 71 additions and 105 deletions.
diff --git a/lib/libzpool/Makefile.am b/lib/libzpool/Makefile.am
@@ -152,7 +152,6 @@ KERNEL_C = \
 	zfs_rlock.c \
 	zil.c \
 	zio.c \
-	zio_os.c \
 	zio_checksum.c \
 	zio_compress.c \
 	zio_crypt.c \

diff --git a/module/os/linux/zfs/Makefile.in b/module/os/linux/zfs/Makefile.in
@@ -19,7 +19,6 @@ $(MODULE)-objs += ../os/linux/zfs/spa_misc_os.o
 $(MODULE)-objs += ../os/linux/zfs/spa_stats.o
 $(MODULE)-objs += ../os/linux/zfs/vdev_disk.o
 $(MODULE)-objs += ../os/linux/zfs/vdev_file.o
-$(MODULE)-objs += ../os/linux/zfs/zio_os.o
 $(MODULE)-objs += ../os/linux/zfs/zfs_acl.o
 $(MODULE)-objs += ../os/linux/zfs/zfs_ctldir.o
 $(MODULE)-objs += ../os/linux/zfs/zfs_debug.o

diff --git a/module/os/linux/zfs/zio_os.c b/module/os/linux/zfs/zio_os.c
diff --git a/module/zfs/zio.c b/module/zfs/zio.c
@@ -1837,6 +1837,77 @@ zio_interrupt(zio_t *zio)
 	zio_taskq_dispatch(zio, ZIO_TASKQ_INTERRUPT, B_FALSE);
 }
 
+void
+zio_delay_interrupt(zio_t *zio)
+{
+	/*
+	 * The timeout_generic() function isn't defined in userspace, so
+	 * rather than trying to implement the function, the zio delay
+	 * functionality has been disabled for userspace builds.
+	 */
+
+#ifdef _KERNEL
+	/*
+	 * If io_target_timestamp is zero, then no delay has been registered
+	 * for this IO, thus jump to the end of this function and "skip" the
+	 * delay; issuing it directly to the zio layer.
+	 */
+	if (zio->io_target_timestamp != 0) {
+		hrtime_t now = gethrtime();
+
+		if (now >= zio->io_target_timestamp) {
+			/*
+			 * This IO has already taken longer than the target
+			 * delay to complete, so we don't want to delay it
+			 * any longer; we "miss" the delay and issue it
+			 * directly to the zio layer. This is likely due to
+			 * the target latency being set to a value less than
+			 * the underlying hardware can satisfy (e.g. delay
+			 * set to 1ms, but the disks take 10ms to complete an
+			 * IO request).
+			 */
+
+			DTRACE_PROBE2(zio__delay__miss, zio_t *, zio,
+			    hrtime_t, now);
+
+			zio_interrupt(zio);
+		} else {
+			taskqid_t tid;
+			hrtime_t diff = zio->io_target_timestamp - now;
+			clock_t expire_at_tick = ddi_get_lbolt() +
+			    NSEC_TO_TICK(diff);
+
+			DTRACE_PROBE3(zio__delay__hit, zio_t *, zio,
+			    hrtime_t, now, hrtime_t, diff);
+
+			if (NSEC_TO_TICK(diff) == 0) {
+				/* Our delay is less than a jiffy - just spin */
+				zfs_sleep_until(zio->io_target_timestamp);
+				zio_interrupt(zio);
+			} else {
+				/*
+				 * Use taskq_dispatch_delay() in the place of
+				 * OpenZFS's timeout_generic().
+				 */
+				tid = taskq_dispatch_delay(system_taskq,
+				    (task_func_t *)zio_interrupt,
+				    zio, TQ_NOSLEEP, expire_at_tick);
+				if (tid == TASKQID_INVALID) {
+					/*
+					 * Couldn't allocate a task.  Just
+					 * finish the zio without a delay.
+					 */
+					zio_interrupt(zio);
+				}
+			}
+		}
+		return;
+	}
+#endif
+	DTRACE_PROBE1(zio__delay__skip, zio_t *, zio);
+	zio_interrupt(zio);
+}
+
 static void
 zio_deadman_impl(zio_t *pio, int ziodepth)
 {