[Qemu-devel] [PATCH 3/5] disk_deadlines: add disk-deadlines option per drive

["Denis V. Lunev" <den@openvz.org>]

From: Raushaniya Maksudova <rmaksudova@virtuozzo.com>

This patch adds per-drive option disk-deadlines.
If it is enabled, one tracks which disk'requests were not completed in time.
By default it is unset.

Signed-off-by: Raushaniya Maksudova <rmaksudova@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
---
 block/Makefile.objs            |  1 +
 block/disk-deadlines.c         | 30 ++++++++++++++++++++++++++++++
 blockdev.c                     | 19 +++++++++++++++++++
 include/block/accounting.h     |  2 ++
 include/block/disk-deadlines.h | 35 +++++++++++++++++++++++++++++++++++
 5 files changed, 87 insertions(+)
 create mode 100644 block/disk-deadlines.c
 create mode 100644 include/block/disk-deadlines.h

diff --git a/block/Makefile.objs b/block/Makefile.objs
index 58ef2ef..cf30ce5 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -20,6 +20,7 @@ block-obj-$(CONFIG_RBD) += rbd.o
 block-obj-$(CONFIG_GLUSTERFS) += gluster.o
 block-obj-$(CONFIG_ARCHIPELAGO) += archipelago.o
 block-obj-$(CONFIG_LIBSSH2) += ssh.o
+block-obj-y += disk-deadlines.o
 block-obj-y += accounting.o
 block-obj-y += write-threshold.o
 
diff --git a/block/disk-deadlines.c b/block/disk-deadlines.c
new file mode 100644
index 0000000..39dec53
--- /dev/null
+++ b/block/disk-deadlines.c
@@ -0,0 +1,30 @@
+/*
+ * QEMU System Emulator disk deadlines control
+ *
+ * Copyright (c) 2015 Raushaniya Maksudova <rmaksudova@virtuozzo.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "block/disk-deadlines.h"
+
+void disk_deadlines_init(DiskDeadlines *disk_deadlines, bool enabled)
+{
+    disk_deadlines->enabled = enabled;
+}
diff --git a/blockdev.c b/blockdev.c
index 6b48be6..6cd9c6e 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -361,6 +361,7 @@ static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
     ThrottleConfig cfg;
     int snapshot = 0;
     bool copy_on_read;
+    bool disk_deadlines;
     Error *error = NULL;
     QemuOpts *opts;
     const char *id;
@@ -394,6 +395,11 @@ static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
     ro = qemu_opt_get_bool(opts, "read-only", 0);
     copy_on_read = qemu_opt_get_bool(opts, "copy-on-read", false);
 
+    disk_deadlines = qdict_get_try_bool(bs_opts, "disk-deadlines", false);
+    if (disk_deadlines) {
+        qdict_del(bs_opts, "disk-deadlines");
+    }
+
     if ((buf = qemu_opt_get(opts, "discard")) != NULL) {
         if (bdrv_parse_discard_flags(buf, &bdrv_flags) != 0) {
             error_setg(errp, "invalid discard option");
@@ -555,6 +561,8 @@ static BlockBackend *blockdev_init(const char *file, QDict *bs_opts,
 
     bs->detect_zeroes = detect_zeroes;
 
+    disk_deadlines_init(&bs->stats.disk_deadlines, disk_deadlines);
+
     bdrv_set_on_error(bs, on_read_error, on_write_error);
 
     /* disk I/O throttling */
@@ -658,6 +666,10 @@ QemuOptsList qemu_legacy_drive_opts = {
             .name = "file",
             .type = QEMU_OPT_STRING,
             .help = "file name",
+        },{
+            .name = "disk-deadlines",
+            .type = QEMU_OPT_BOOL,
+            .help = "control of disk requests' time execution",
         },
 
         /* Options that are passed on, but have special semantics with -drive */
@@ -698,6 +710,7 @@ DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type)
     const char *werror, *rerror;
     bool read_only = false;
     bool copy_on_read;
+    bool disk_deadlines;
     const char *serial;
     const char *filename;
     Error *local_err = NULL;
@@ -812,6 +825,12 @@ DriveInfo *drive_new(QemuOpts *all_opts, BlockInterfaceType block_default_type)
     qdict_put(bs_opts, "copy-on-read",
               qstring_from_str(copy_on_read ? "on" :"off"));
 
+    /* Enable control of disk requests' time execution */
+    disk_deadlines = qemu_opt_get_bool(legacy_opts, "disk-deadlines", false);
+    if (disk_deadlines) {
+        qdict_put(bs_opts, "disk-deadlines", qbool_from_bool(disk_deadlines));
+    }
+
     /* Controller type */
     value = qemu_opt_get(legacy_opts, "if");
     if (value) {
diff --git a/include/block/accounting.h b/include/block/accounting.h
index 4c406cf..4e2b345 100644
--- a/include/block/accounting.h
+++ b/include/block/accounting.h
@@ -27,6 +27,7 @@
 #include <stdint.h>
 
 #include "qemu/typedefs.h"
+#include "block/disk-deadlines.h"
 
 enum BlockAcctType {
     BLOCK_ACCT_READ,
@@ -41,6 +42,7 @@ typedef struct BlockAcctStats {
     uint64_t total_time_ns[BLOCK_MAX_IOTYPE];
     uint64_t merged[BLOCK_MAX_IOTYPE];
     uint64_t wr_highest_sector;
+    DiskDeadlines disk_deadlines;
 } BlockAcctStats;
 
 typedef struct BlockAcctCookie {
diff --git a/include/block/disk-deadlines.h b/include/block/disk-deadlines.h
new file mode 100644
index 0000000..2ea193b
--- /dev/null
+++ b/include/block/disk-deadlines.h
@@ -0,0 +1,35 @@
+/*
+ * QEMU System Emulator disk deadlines control
+ *
+ * Copyright (c) 2015 Raushaniya Maksudova <rmaksudova@virtuozzo.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef DISK_DEADLINES_H
+#define DISK_DEADLINES_H
+
+#include <stdbool.h>
+
+typedef struct DiskDeadlines {
+    bool enabled;
+} DiskDeadlines;
+
+void disk_deadlines_init(DiskDeadlines *disk_deadlines, bool enabled);
+
+#endif
-- 
2.1.4