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Diffstat (limited to 'target/linux/generic/backport-5.4/602-v5.12-net-add-sysfs-attribute-to-control-napi-threaded-mod.patch')
-rw-r--r--target/linux/generic/backport-5.4/602-v5.12-net-add-sysfs-attribute-to-control-napi-threaded-mod.patch177
1 files changed, 0 insertions, 177 deletions
diff --git a/target/linux/generic/backport-5.4/602-v5.12-net-add-sysfs-attribute-to-control-napi-threaded-mod.patch b/target/linux/generic/backport-5.4/602-v5.12-net-add-sysfs-attribute-to-control-napi-threaded-mod.patch
deleted file mode 100644
index bdc34a15ea..0000000000
--- a/target/linux/generic/backport-5.4/602-v5.12-net-add-sysfs-attribute-to-control-napi-threaded-mod.patch
+++ /dev/null
@@ -1,177 +0,0 @@
-From: Wei Wang <weiwan@google.com>
-Date: Mon, 8 Feb 2021 11:34:10 -0800
-Subject: [PATCH] net: add sysfs attribute to control napi threaded mode
-
-This patch adds a new sysfs attribute to the network device class.
-Said attribute provides a per-device control to enable/disable the
-threaded mode for all the napi instances of the given network device,
-without the need for a device up/down.
-User sets it to 1 or 0 to enable or disable threaded mode.
-Note: when switching between threaded and the current softirq based mode
-for a napi instance, it will not immediately take effect if the napi is
-currently being polled. The mode switch will happen for the next time
-napi_schedule() is called.
-
-Co-developed-by: Paolo Abeni <pabeni@redhat.com>
-Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-Co-developed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
-Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
-Co-developed-by: Felix Fietkau <nbd@nbd.name>
-Signed-off-by: Felix Fietkau <nbd@nbd.name>
-Signed-off-by: Wei Wang <weiwan@google.com>
-Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
-Signed-off-by: David S. Miller <davem@davemloft.net>
----
-
---- a/Documentation/ABI/testing/sysfs-class-net
-+++ b/Documentation/ABI/testing/sysfs-class-net
-@@ -301,3 +301,18 @@ Contact: netdev@vger.kernel.org
- Description:
- 32-bit unsigned integer counting the number of times the link has
- been down
-+
-+What: /sys/class/net/<iface>/threaded
-+Date: Jan 2021
-+KernelVersion: 5.12
-+Contact: netdev@vger.kernel.org
-+Description:
-+ Boolean value to control the threaded mode per device. User could
-+ set this value to enable/disable threaded mode for all napi
-+ belonging to this device, without the need to do device up/down.
-+
-+ Possible values:
-+ == ==================================
-+ 0 threaded mode disabled for this dev
-+ 1 threaded mode enabled for this dev
-+ == ==================================
---- a/include/linux/netdevice.h
-+++ b/include/linux/netdevice.h
-@@ -498,6 +498,8 @@ static inline bool napi_complete(struct
- */
- bool napi_hash_del(struct napi_struct *napi);
-
-+int dev_set_threaded(struct net_device *dev, bool threaded);
-+
- /**
- * napi_disable - prevent NAPI from scheduling
- * @n: NAPI context
---- a/net/core/dev.c
-+++ b/net/core/dev.c
-@@ -3914,8 +3914,9 @@ static inline void ____napi_schedule(str
-
- if (test_bit(NAPI_STATE_THREADED, &napi->state)) {
- /* Paired with smp_mb__before_atomic() in
-- * napi_enable(). Use READ_ONCE() to guarantee
-- * a complete read on napi->thread. Only call
-+ * napi_enable()/dev_set_threaded().
-+ * Use READ_ONCE() to guarantee a complete
-+ * read on napi->thread. Only call
- * wake_up_process() when it's not NULL.
- */
- thread = READ_ONCE(napi->thread);
-@@ -6293,6 +6294,49 @@ static void init_gro_hash(struct napi_st
- napi->gro_bitmask = 0;
- }
-
-+int dev_set_threaded(struct net_device *dev, bool threaded)
-+{
-+ struct napi_struct *napi;
-+ int err = 0;
-+
-+ if (dev->threaded == threaded)
-+ return 0;
-+
-+ if (threaded) {
-+ list_for_each_entry(napi, &dev->napi_list, dev_list) {
-+ if (!napi->thread) {
-+ err = napi_kthread_create(napi);
-+ if (err) {
-+ threaded = false;
-+ break;
-+ }
-+ }
-+ }
-+ }
-+
-+ dev->threaded = threaded;
-+
-+ /* Make sure kthread is created before THREADED bit
-+ * is set.
-+ */
-+ smp_mb__before_atomic();
-+
-+ /* Setting/unsetting threaded mode on a napi might not immediately
-+ * take effect, if the current napi instance is actively being
-+ * polled. In this case, the switch between threaded mode and
-+ * softirq mode will happen in the next round of napi_schedule().
-+ * This should not cause hiccups/stalls to the live traffic.
-+ */
-+ list_for_each_entry(napi, &dev->napi_list, dev_list) {
-+ if (threaded)
-+ set_bit(NAPI_STATE_THREADED, &napi->state);
-+ else
-+ clear_bit(NAPI_STATE_THREADED, &napi->state);
-+ }
-+
-+ return err;
-+}
-+
- void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
- int (*poll)(struct napi_struct *, int), int weight)
- {
---- a/net/core/net-sysfs.c
-+++ b/net/core/net-sysfs.c
-@@ -557,6 +557,45 @@ static ssize_t phys_switch_id_show(struc
- }
- static DEVICE_ATTR_RO(phys_switch_id);
-
-+static ssize_t threaded_show(struct device *dev,
-+ struct device_attribute *attr, char *buf)
-+{
-+ struct net_device *netdev = to_net_dev(dev);
-+ ssize_t ret = -EINVAL;
-+
-+ if (!rtnl_trylock())
-+ return restart_syscall();
-+
-+ if (dev_isalive(netdev))
-+ ret = sprintf(buf, fmt_dec, netdev->threaded);
-+
-+ rtnl_unlock();
-+ return ret;
-+}
-+
-+static int modify_napi_threaded(struct net_device *dev, unsigned long val)
-+{
-+ int ret;
-+
-+ if (list_empty(&dev->napi_list))
-+ return -EOPNOTSUPP;
-+
-+ if (val != 0 && val != 1)
-+ return -EOPNOTSUPP;
-+
-+ ret = dev_set_threaded(dev, val);
-+
-+ return ret;
-+}
-+
-+static ssize_t threaded_store(struct device *dev,
-+ struct device_attribute *attr,
-+ const char *buf, size_t len)
-+{
-+ return netdev_store(dev, attr, buf, len, modify_napi_threaded);
-+}
-+static DEVICE_ATTR_RW(threaded);
-+
- static struct attribute *net_class_attrs[] __ro_after_init = {
- &dev_attr_netdev_group.attr,
- &dev_attr_type.attr,
-@@ -587,6 +626,7 @@ static struct attribute *net_class_attrs
- &dev_attr_proto_down.attr,
- &dev_attr_carrier_up_count.attr,
- &dev_attr_carrier_down_count.attr,
-+ &dev_attr_threaded.attr,
- NULL,
- };
- ATTRIBUTE_GROUPS(net_class);