limit xen vnic max queues number to online cpus number

PATCH Superseded Joe Jin 2 participants 9 messages Oct 23, 2015

Subsystems (4)

Networking Network drivers Xen hypervisor interface Xen network backend driver

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Joe Jin

author

2015-10-23 09:17 UTC #0 lore raw

v2 cover limit xen vnic max queues number to online cpus number

Currently xen vnic allowed to create lots of queues by set module param max_queues(both netback and netfront), when queues number larger than cpus number, it does not help for performance but need more cpu time.

This patchset limit netback and netfront max queues number to online cpus number.

Joe Jin (2):
xen-netback: limit xen vif max queues number to online cpus
xen-netfront: limit vnic max_queues number to online cpus

---
Changes in v2:
- Replace param_get_int to param_get_uint.
- Use '%u' for unsigned int when print.
- Replace EINVAL to ERANGE when out of range [0-CPUs].
- Reset the perm of max_queues on sysfs to 0644.

 drivers/net/xen-netback/netback.c |   28 ++++++++++++++++++++++------
 drivers/net/xen-netfront.c        |   28 ++++++++++++++++++++++------
 2 files changed, 44 insertions(+), 12 deletions(-)

Joe Jin

author

2015-10-23 09:18 UTC #1 lore raw

PATCH v2 1/2 xen-netback: limit xen vif max queues number to online cpus

Should not allocate xen vif queues number more than online cpus.

Signed-off-by Joe Jin <[email protected]>

Cc Jan Beulich <[email protected]>

Cc Wei Liu <[email protected]>

Cc Ian Campbell <[email protected]>

Cc Boris Ostrovsky <[email protected]>

Cc Konrad Rzeszutek Wilk <[email protected]>

---
 drivers/net/xen-netback/netback.c |   28 ++++++++++++++++++++++------
 1 files changed, 22 insertions(+), 6 deletions(-)

drivers/net/xen-netback/netback.c +22 -6

index ec98d43..021dcb0 100644
@@ -68,7 +68,9 @@ unsigned int rx_stall_timeout_msecs = 60000;
 module_param(rx_stall_timeout_msecs, uint, 0444);
 
 unsigned int xenvif_max_queues;
-module_param_named(max_queues, xenvif_max_queues, uint, 0644);
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp);
+module_param_call(max_queues, xennet_set_max_queues, param_get_uint,
+		  &xenvif_max_queues, 0644);
 MODULE_PARM_DESC(max_queues,
 		 "Maximum number of queues per virtual interface");

@@ -107,6 +109,20 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif_queue *queue
 					     u16      size,
 					     u16      flags);
 
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_info("max_queues %u is out of range [0 - %u]!\n", 
+			max_queues, cpus);
+		return -ERANGE;
+	}
+
+	return param_set_uint(val, kp);
+}
+
 static inline unsigned long idx_to_pfn(struct xenvif_queue *queue,
 				       u16 idx)
 {

@@ -2110,15 +2126,15 @@ int xenvif_dealloc_kthread(void *data)
 static int __init netback_init(void)
 {
 	int rc = 0;
+	unsigned int cpus = num_online_cpus();
 
 	if (!xen_domain())
 		return -ENODEV;
 
-	/* Allow as many queues as there are CPUs if user has not
-	 * specified a value.
-	 */
-	if (xenvif_max_queues == 0)
-		xenvif_max_queues = num_online_cpus();
+	/* Allow at most as many queues as CPUs. */
+	if (xenvif_max_queues == 0 || xenvif_max_queues > cpus)
+		xenvif_max_queues = cpus;
+	pr_info("vif max_queues: %u\n", xenvif_max_queues);
 
 	if (fatal_skb_slots < XEN_NETBK_LEGACY_SLOTS_MAX) {
 		pr_info("fatal_skb_slots too small (%d), bump it to XEN_NETBK_LEGACY_SLOTS_MAX (%d)\n",

Signature · 1 line

1.7.1

Joe Jin

author

2015-10-23 09:18 UTC #2 lore raw

PATCH v2 1/2 xen-netback: limit xen vif max queues number to online cpus

In reply to Joe Jin

Should not allocate xen vif queues number more than online cpus.

Signed-off-by Joe Jin <[email protected]>

Cc Jan Beulich <[email protected]>

Cc Wei Liu <[email protected]>

Cc Ian Campbell <[email protected]>

Cc Boris Ostrovsky <[email protected]>

Cc Konrad Rzeszutek Wilk <[email protected]>

---
 drivers/net/xen-netback/netback.c |   28 ++++++++++++++++++++++------
 1 files changed, 22 insertions(+), 6 deletions(-)

drivers/net/xen-netback/netback.c +22 -6

index ec98d43..021dcb0 100644
@@ -68,7 +68,9 @@ unsigned int rx_stall_timeout_msecs = 60000;
 module_param(rx_stall_timeout_msecs, uint, 0444);
 
 unsigned int xenvif_max_queues;
-module_param_named(max_queues, xenvif_max_queues, uint, 0644);
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp);
+module_param_call(max_queues, xennet_set_max_queues, param_get_uint,
+		  &xenvif_max_queues, 0644);
 MODULE_PARM_DESC(max_queues,
 		 "Maximum number of queues per virtual interface");

@@ -107,6 +109,20 @@ static struct xen_netif_rx_response *make_rx_response(struct xenvif_queue *queue
 					     u16      size,
 					     u16      flags);
 
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_info("max_queues %u is out of range [0 - %u]!\n", 
+			max_queues, cpus);
+		return -ERANGE;
+	}
+
+	return param_set_uint(val, kp);
+}
+
 static inline unsigned long idx_to_pfn(struct xenvif_queue *queue,
 				       u16 idx)
 {

@@ -2110,15 +2126,15 @@ int xenvif_dealloc_kthread(void *data)
 static int __init netback_init(void)
 {
 	int rc = 0;
+	unsigned int cpus = num_online_cpus();
 
 	if (!xen_domain())
 		return -ENODEV;
 
-	/* Allow as many queues as there are CPUs if user has not
-	 * specified a value.
-	 */
-	if (xenvif_max_queues == 0)
-		xenvif_max_queues = num_online_cpus();
+	/* Allow at most as many queues as CPUs. */
+	if (xenvif_max_queues == 0 || xenvif_max_queues > cpus)
+		xenvif_max_queues = cpus;
+	pr_info("vif max_queues: %u\n", xenvif_max_queues);
 
 	if (fatal_skb_slots < XEN_NETBK_LEGACY_SLOTS_MAX) {
 		pr_info("fatal_skb_slots too small (%d), bump it to XEN_NETBK_LEGACY_SLOTS_MAX (%d)\n",

Signature · 1 line

1.7.1

Joe Jin

author

2015-10-23 09:19 UTC #3 lore raw

PATCH v2 2/2 xen-netfront: limit vnic max_queues number to online cpus

In reply to Joe Jin

Should not allocate vnic queues number more than online cpus.

Signed-off-by Joe Jin <[email protected]>

Cc Jan Beulich <[email protected]>

Cc Wei Liu <[email protected]>

Cc Ian Campbell <[email protected]>

Cc Boris Ostrovsky <[email protected]>

Cc Konrad Rzeszutek Wilk <[email protected]>

---
 drivers/net/xen-netfront.c |   28 ++++++++++++++++++++++------
 1 files changed, 22 insertions(+), 6 deletions(-)

drivers/net/xen-netfront.c +22 -6

index f821a97..5cc2f4a 100644
@@ -58,7 +58,9 @@
 
 /* Module parameters */
 static unsigned int xennet_max_queues;
-module_param_named(max_queues, xennet_max_queues, uint, 0644);
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp);
+module_param_call(max_queues, xennet_set_max_queues, param_get_uint,
+		  &xennet_max_queues, 0644);
 MODULE_PARM_DESC(max_queues,
 		 "Maximum number of queues per virtual interface");

@@ -164,6 +166,19 @@ struct netfront_rx_info {
 	struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 };
 
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_err("max_queues %u is out of range [0 - %u]!\n", 
+		       max_queues, cpus);
+		return -ERANGE;
+	}
+	return param_set_uint(val, kp);
+}
+
 static void skb_entry_set_link(union skb_entry *list, unsigned short id)
 {
 	list->link = id;

@@ -2126,6 +2141,8 @@ static struct xenbus_driver netfront_driver = {
 
 static int __init netif_init(void)
 {
+	unsigned int cpus = num_online_cpus();
+
 	if (!xen_domain())
 		return -ENODEV;

@@ -2134,11 +2151,10 @@ static int __init netif_init(void)
 
 	pr_info("Initialising Xen virtual ethernet driver\n");
 
-	/* Allow as many queues as there are CPUs if user has not
-	 * specified a value.
-	 */
-	if (xennet_max_queues == 0)
-		xennet_max_queues = num_online_cpus();
+	/* Allow at most as many queues as there are CPUs. */
+	if (xennet_max_queues == 0 || xennet_max_queues > cpus)
+		xennet_max_queues = cpus;
+	pr_info("max_queues: %d\n", xennet_max_queues);
 
 	return xenbus_register_frontend(&netfront_driver);
 }

Signature · 1 line

1.7.1

Joe Jin

author

2015-10-23 09:19 UTC #4 lore raw

PATCH v2 2/2 xen-netfront: limit vnic max_queues number to online cpus

In reply to Joe Jin

Should not allocate vnic queues number more than online cpus.

Signed-off-by Joe Jin <[email protected]>

Cc Jan Beulich <[email protected]>

Cc Wei Liu <[email protected]>

Cc Ian Campbell <[email protected]>

Cc Boris Ostrovsky <[email protected]>

Cc Konrad Rzeszutek Wilk <[email protected]>

---
 drivers/net/xen-netfront.c |   28 ++++++++++++++++++++++------
 1 files changed, 22 insertions(+), 6 deletions(-)

drivers/net/xen-netfront.c +22 -6

index f821a97..5cc2f4a 100644
@@ -58,7 +58,9 @@
 
 /* Module parameters */
 static unsigned int xennet_max_queues;
-module_param_named(max_queues, xennet_max_queues, uint, 0644);
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp);
+module_param_call(max_queues, xennet_set_max_queues, param_get_uint,
+		  &xennet_max_queues, 0644);
 MODULE_PARM_DESC(max_queues,
 		 "Maximum number of queues per virtual interface");

@@ -164,6 +166,19 @@ struct netfront_rx_info {
 	struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 };
 
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_err("max_queues %u is out of range [0 - %u]!\n", 
+		       max_queues, cpus);
+		return -ERANGE;
+	}
+	return param_set_uint(val, kp);
+}
+
 static void skb_entry_set_link(union skb_entry *list, unsigned short id)
 {
 	list->link = id;

@@ -2126,6 +2141,8 @@ static struct xenbus_driver netfront_driver = {
 
 static int __init netif_init(void)
 {
+	unsigned int cpus = num_online_cpus();
+
 	if (!xen_domain())
 		return -ENODEV;

@@ -2134,11 +2151,10 @@ static int __init netif_init(void)
 
 	pr_info("Initialising Xen virtual ethernet driver\n");
 
-	/* Allow as many queues as there are CPUs if user has not
-	 * specified a value.
-	 */
-	if (xennet_max_queues == 0)
-		xennet_max_queues = num_online_cpus();
+	/* Allow at most as many queues as there are CPUs. */
+	if (xennet_max_queues == 0 || xennet_max_queues > cpus)
+		xennet_max_queues = cpus;
+	pr_info("max_queues: %d\n", xennet_max_queues);
 
 	return xenbus_register_frontend(&netfront_driver);
 }

Signature · 1 line

1.7.1

Jan Beulich

2015-10-23 09:30 UTC #5 lore raw

Re: [PATCH V2 2/2] xen-netfront: limit vnic max_queues number to online cpus

drivers/net/xen-netfront.c struct netfront_rx_info { · line 175

Quoted 13 lines

Quoted 1 line

Quoted 1 line · On 23.10.15 at 11:19, <[email protected]> wrote:

drivers/net/xen-netfront.c +7 -0

@@ -164,6 +166,19 @@ struct netfront_rx_info {
 	struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 };
 
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_err("max_queues %u is out of range [0 - %u]!\n",

I suppose you mean "...[1 - %u]!\n" here?

Jan

Joe Jin

author

2015-10-23 09:39 UTC #6 lore raw

Re: [PATCH V2 2/2] xen-netfront: limit vnic max_queues number to online cpus

Quoted 6 lines · Jan Beulich

Quoted 6 lines
Quoted 1 line
Quoted 1 line · On 23.10.15 at 11:19, <[email protected]> wrote:
drivers/net/xen-netfront.c +0 -0
@@ -164,6 +166,19 @@ struct netfront_rx_info {
 	struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 };
 

Quoted 9 lines

drivers/net/xen-netfront.c struct netfront_rx_info { · line 175

Quoted 7 lines

drivers/net/xen-netfront.c +7 -0

+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_err("max_queues %u is out of range [0 - %u]!\n",

I suppose you mean "...[1 - %u]!\n" here?

Yes you are right, you catch my fault again :)

Thanks so much, will resend new later.

Regards,
Joe

Quoted 2 lines

Jan

Signature · 4 lines

Oracle <http://www.oracle.com>
Joe Jin | Software Development Director | +8610.6106.5624
ORACLE | Linux and Virtualization
No. 24 Zhongguancun Software Park, Haidian District | 100193 Beijing

Joe Jin

author

2015-10-23 09:39 UTC #7 lore raw

Re: [PATCH V2 2/2] xen-netfront: limit vnic max_queues number to online cpus

In reply to Jan Beulich

Quoted 6 lines · Jan Beulich

Quoted 6 lines
Quoted 1 line
Quoted 1 line · On 23.10.15 at 11:19, <[email protected]> wrote:
drivers/net/xen-netfront.c +0 -0
@@ -164,6 +166,19 @@ struct netfront_rx_info {
 	struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 };
 

Quoted 9 lines

drivers/net/xen-netfront.c struct netfront_rx_info { · line 175

Quoted 7 lines

drivers/net/xen-netfront.c +7 -0

+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_err("max_queues %u is out of range [0 - %u]!\n",

I suppose you mean "...[1 - %u]!\n" here?

Yes you are right, you catch my fault again :)

Thanks so much, will resend new later.

Regards,
Joe

Quoted 2 lines

Jan

Signature · 4 lines

Oracle <http://www.oracle.com>
Joe Jin | Software Development Director | +8610.6106.5624
ORACLE | Linux and Virtualization
No. 24 Zhongguancun Software Park, Haidian District | 100193 Beijing

Jan Beulich

2015-10-23 09:30 UTC #8 lore raw

Re: [PATCH V2 2/2] xen-netfront: limit vnic max_queues number to online cpus

In reply to Joe Jin

drivers/net/xen-netfront.c struct netfront_rx_info { · line 175

Quoted 13 lines

Quoted 1 line

Quoted 1 line · On 23.10.15 at 11:19, <[email protected]> wrote:

drivers/net/xen-netfront.c +7 -0

@@ -164,6 +166,19 @@ struct netfront_rx_info {
 	struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX - 1];
 };
 
+static int xennet_set_max_queues(const char *val, struct kernel_param *kp)
+{
+	unsigned int cpus = num_online_cpus();
+	unsigned int max_queues = simple_strtoul(val, NULL, 10);
+
+	if (max_queues == 0 || max_queues > cpus) {
+		pr_err("max_queues %u is out of range [0 - %u]!\n",

I suppose you mean "...[1 - %u]!\n" here?

Jan