[Devel] [PATCH RHEL7 COMMIT] target/iscsi: add an ability to set io limits for iscsi targets
Konstantin Khorenko
khorenko at virtuozzo.com
Thu Mar 15 15:34:20 MSK 2018
The commit is pushed to "branch-rh7-3.10.0-693.17.1.vz7.45.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-693.17.1.vz7.45.7
------>
commit 69522a6e5628c209ad47e09fcae5275749a952e9
Author: Andrei Vagin <avagin at openvz.org>
Date: Thu Mar 15 15:34:20 2018 +0300
target/iscsi: add an ability to set io limits for iscsi targets
This patch add an ability to set a blkio cgroup for an iscsi target.
When a new client is connected, the kernel creates two kernel threads and
run all io requests from them, this means that we can set a blkio group
for these threads and set io limits via this group.
Here is an exampe how this works:
$ TGT_PATH=/sys/kernel/config/target/iscsi/iqn.2014-06.com.vstorage\:test
$ CG_PATH=/sys/fs/cgroup/blkio/system.slice/vstorage-iscsi/
# create a group
$ mkdir -p $CG_PATH
# set cgroup for iscsi target
$ bash -c 'echo $$ > $CG_PATH/tasks &&
echo 1 > $TGT_PATH/tpgt_1/param/BlkioCgroup'
$ cat $TGT_PATH/tpgt_1/param/BlkioCgroup
/system.slice/vstorage-iscsi
# attach iscsi target
$ IQN=iqn.2014-06.com.vstorage:test
$ iscsiadm -m node -T $IQN -l
Logging in to [iface: default, target: iqn.2014-06.com.vstorage:test,
portal: 10.94.120.187,3260] (multiple)
Login to [iface: default, target: iqn.2014-06.com.vstorage:test, portal:
10.94.120.187,3260] successful.
# check that iscsi threads in the required cgroup
$ ps -C iscsi_ttx
PID TTY TIME CMD
4097 ? 00:00:00 iscsi_ttx
$ cat /proc/4097/cgroup | grep blkio
1:blkio:/system.slice/vstorage-iscsi
# set io limits for a target backing store device
$ ploop list
ploop15810 /mnt/vstorage/vols/iscsi/iqn.2014-06.com.vstorage:test/lun1/ploop
$ ls -l /dev/ploop15810
brw-rw---- 1 root disk 182, 252960 Mar 14 00:59 /dev/ploop15810
$ echo "182:252960 6291456" > $CG_PATH/blkio.throttle.read_bps_device
# check that limits work as expected
$ dd if=/dev/sda of=/dev/null bs=10M count=10
10+0 records in
10+0 records out
104857600 bytes (105 MB) copied, 17.3534 s, 6.0 MB/s
Signed-off-by: Andrei Vagin <avagin at openvz.org>
---
drivers/target/iscsi/iscsi_target_configfs.c | 46 ++++++++++++++++++++++++++++
drivers/target/iscsi/iscsi_target_login.c | 34 +++++++++++++++++++-
drivers/target/iscsi/iscsi_target_tpg.c | 36 ++++++++++++++++++++++
drivers/target/iscsi/iscsi_target_tpg.h | 2 ++
include/target/iscsi/iscsi_target_core.h | 2 ++
kernel/cgroup.c | 1 +
6 files changed, 120 insertions(+), 1 deletion(-)
diff --git a/drivers/target/iscsi/iscsi_target_configfs.c b/drivers/target/iscsi/iscsi_target_configfs.c
index e6631abc9d0c..6d754cfe3fc4 100644
--- a/drivers/target/iscsi/iscsi_target_configfs.c
+++ b/drivers/target/iscsi/iscsi_target_configfs.c
@@ -1412,6 +1412,51 @@ TPG_PARAM_ATTR(IFMarkInt, S_IRUGO | S_IWUSR);
DEF_TPG_PARAM(OFMarkInt);
TPG_PARAM_ATTR(OFMarkInt, S_IRUGO | S_IWUSR);
+static ssize_t iscsi_tpg_param_show_BlkioCgroup(
+ struct se_portal_group *se_tpg,
+ char *page)
+{
+ struct iscsi_portal_group *tpg = container_of(se_tpg,
+ struct iscsi_portal_group, tpg_se_tpg);
+ ssize_t rb;
+
+ if (iscsit_get_tpg(tpg) < 0)
+ return -EINVAL;
+
+ rb = iscsit_ta_tpg_show_blkcg(tpg, page);
+ iscsit_put_tpg(tpg);
+ return rb;
+}
+
+static ssize_t iscsi_tpg_param_store_BlkioCgroup(
+ struct se_portal_group *se_tpg,
+ const char *page,
+ size_t count)
+{
+ struct iscsi_portal_group *tpg = container_of(se_tpg,
+ struct iscsi_portal_group, tpg_se_tpg);
+ u32 val;
+ int ret;
+
+ if (iscsit_get_tpg(tpg) < 0)
+ return -EINVAL;
+
+ ret = kstrtou32(page, 0, &val);
+ if (ret)
+ goto out;
+ ret = iscsit_ta_tpg_set_blkcg(tpg, val);
+ if (ret < 0)
+ goto out;
+
+ iscsit_put_tpg(tpg);
+ return count;
+out:
+ iscsit_put_tpg(tpg);
+ return ret;
+}
+
+TPG_PARAM_ATTR(BlkioCgroup, S_IRUGO | S_IWUSR);
+
static struct configfs_attribute *lio_target_tpg_param_attrs[] = {
&iscsi_tpg_param_AuthMethod.attr,
&iscsi_tpg_param_HeaderDigest.attr,
@@ -1434,6 +1479,7 @@ static struct configfs_attribute *lio_target_tpg_param_attrs[] = {
&iscsi_tpg_param_OFMarker.attr,
&iscsi_tpg_param_IFMarkInt.attr,
&iscsi_tpg_param_OFMarkInt.attr,
+ &iscsi_tpg_param_BlkioCgroup.attr,
NULL,
};
diff --git a/drivers/target/iscsi/iscsi_target_login.c b/drivers/target/iscsi/iscsi_target_login.c
index c20b561f759f..4f594164ce47 100644
--- a/drivers/target/iscsi/iscsi_target_login.c
+++ b/drivers/target/iscsi/iscsi_target_login.c
@@ -20,6 +20,7 @@
#include <linux/string.h>
#include <linux/kthread.h>
#include <linux/idr.h>
+#include <linux/cgroup.h>
#include <scsi/iscsi_proto.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
@@ -712,8 +713,18 @@ static void iscsi_post_login_start_timers(struct iscsi_conn *conn)
int iscsit_start_kthreads(struct iscsi_conn *conn)
{
+ struct iscsi_portal_group *tpg = conn->tpg;
+ struct cgroup_subsys_state *blk_css = NULL;
int ret = 0;
+ if (iscsit_get_tpg(tpg) < 0)
+ return -EINVAL;
+ if (tpg->blk_css) {
+ blk_css = tpg->blk_css;
+ css_get(blk_css);
+ }
+ iscsit_put_tpg(tpg);
+
spin_lock(&iscsit_global->ts_bitmap_lock);
conn->bitmap_id = bitmap_find_free_region(iscsit_global->ts_bitmap,
ISCSIT_BITMAP_BITS, get_order(1));
@@ -722,7 +733,8 @@ int iscsit_start_kthreads(struct iscsi_conn *conn)
if (conn->bitmap_id < 0) {
pr_err("bitmap_find_free_region() failed for"
" iscsit_start_kthreads()\n");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto put_blk_css;
}
conn->tx_thread = kthread_run(iscsi_target_tx_thread, conn,
@@ -732,6 +744,11 @@ int iscsit_start_kthreads(struct iscsi_conn *conn)
ret = PTR_ERR(conn->tx_thread);
goto out_bitmap;
}
+ if (blk_css) {
+ ret = cgroup_kernel_attach(blk_css->cgroup, conn->tx_thread);
+ if (ret < 0)
+ goto out_tx;
+ }
conn->tx_thread_active = true;
conn->rx_thread = kthread_run(iscsi_target_rx_thread, conn,
@@ -741,9 +758,21 @@ int iscsit_start_kthreads(struct iscsi_conn *conn)
ret = PTR_ERR(conn->rx_thread);
goto out_tx;
}
+ if (blk_css) {
+ ret = cgroup_kernel_attach(blk_css->cgroup, conn->rx_thread);
+ if (ret < 0)
+ goto out_rx;
+ }
conn->rx_thread_active = true;
+ if (blk_css)
+ css_put(blk_css);
+
return 0;
+out_rx:
+ send_sig(SIGINT, conn->rx_thread, 1);
+ kthread_stop(conn->rx_thread);
+ conn->rx_thread_active = false;
out_tx:
send_sig(SIGINT, conn->tx_thread, 1);
kthread_stop(conn->tx_thread);
@@ -753,6 +782,9 @@ int iscsit_start_kthreads(struct iscsi_conn *conn)
bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
get_order(1));
spin_unlock(&iscsit_global->ts_bitmap_lock);
+put_blk_css:
+ if (blk_css)
+ css_put(blk_css);
return ret;
}
diff --git a/drivers/target/iscsi/iscsi_target_tpg.c b/drivers/target/iscsi/iscsi_target_tpg.c
index 2426b0bae643..792d3eecc16f 100644
--- a/drivers/target/iscsi/iscsi_target_tpg.c
+++ b/drivers/target/iscsi/iscsi_target_tpg.c
@@ -16,6 +16,7 @@
* GNU General Public License for more details.
******************************************************************************/
+#include <linux/cgroup.h>
#include <target/target_core_base.h>
#include <target/target_core_fabric.h>
#include <target/target_core_configfs.h>
@@ -303,6 +304,9 @@ int iscsit_tpg_del_portal_group(
list_del(&tpg->tpg_list);
spin_unlock(&tiqn->tiqn_tpg_lock);
+ if (tpg->blk_css)
+ css_put(tpg->blk_css);
+
pr_debug("CORE[%s]_TPG[%hu] - Deleted iSCSI Target Portal Group\n",
tiqn->tiqn, tpg->tpgt);
@@ -896,3 +900,35 @@ int iscsit_ta_tpg_enabled_sendtargets(
return 0;
}
+
+int iscsit_ta_tpg_set_blkcg(struct iscsi_portal_group *tpg, u32 flag)
+{
+ struct cgroup_subsys_state *css;
+
+ if (flag != 1)
+ return -EINVAL;
+
+ css = task_get_css(current, blkio_subsys_id);
+ if (tpg->blk_css)
+ css_put(tpg->blk_css);
+ tpg->blk_css = css;
+
+ return 0;
+}
+
+int iscsit_ta_tpg_show_blkcg(struct iscsi_portal_group *tpg, char *page)
+{
+ int rb;
+
+ if (tpg->blk_css) {
+ rb = cgroup_path(tpg->blk_css->cgroup, page, PAGE_SIZE - 1);
+ if (rb == 0)
+ rb = strlen(page);
+ page[rb] = '\n';
+ page[rb + 1] = 0;
+ rb++;
+ } else
+ rb = 0;
+
+ return rb;
+}
diff --git a/drivers/target/iscsi/iscsi_target_tpg.h b/drivers/target/iscsi/iscsi_target_tpg.h
index b2f49c0fd13a..416b9290ef28 100644
--- a/drivers/target/iscsi/iscsi_target_tpg.h
+++ b/drivers/target/iscsi/iscsi_target_tpg.h
@@ -40,5 +40,7 @@ extern int iscsit_ta_demo_mode_discovery(struct iscsi_portal_group *, u32);
extern int iscsit_ta_default_erl(struct iscsi_portal_group *, u32);
extern int iscsit_ta_t10_pi(struct iscsi_portal_group *, u32);
extern int iscsit_ta_tpg_enabled_sendtargets(struct iscsi_portal_group *, u32);
+extern int iscsit_ta_tpg_set_blkcg(struct iscsi_portal_group *tpg, u32 flag);
+extern int iscsit_ta_tpg_show_blkcg(struct iscsi_portal_group *tpg, char *page);
#endif /* ISCSI_TARGET_TPG_H */
diff --git a/include/target/iscsi/iscsi_target_core.h b/include/target/iscsi/iscsi_target_core.h
index 3e3b2f9e902b..83eb63bbec0d 100644
--- a/include/target/iscsi/iscsi_target_core.h
+++ b/include/target/iscsi/iscsi_target_core.h
@@ -838,6 +838,8 @@ struct iscsi_portal_group {
struct iscsi_tiqn *tpg_tiqn;
struct list_head tpg_gnp_list;
struct list_head tpg_list;
+
+ struct cgroup_subsys_state *blk_css;
} ____cacheline_aligned;
struct iscsi_wwn_stat_grps {
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index dd808689aee6..e17e9529b2fd 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5927,6 +5927,7 @@ int cgroup_kernel_attach(struct cgroup *cgrp, struct task_struct *tsk)
mutex_unlock(&cgroup_mutex);
return ret;
}
+EXPORT_SYMBOL_GPL(cgroup_kernel_attach);
void cgroup_kernel_close(struct cgroup *cgrp)
{
More information about the Devel
mailing list