From 43c7bd1ffcd1621c64cedf1be52156e2f95bba9b Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Wed, 22 Mar 2017 14:51:02 -0700 Subject: [PATCH] netvsc: use refcount_t for keeping track of sub channels Rather than a lock and variable, use a refcount_t to keep track of the number of sub channels. Don't need to wait for subchannels on device removal since wait was already done in device_add. Also fix the error handling; don't wait forever in case of an error on request to create sub channels. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- drivers/net/hyperv/hyperv_net.h | 4 +-- drivers/net/hyperv/rndis_filter.c | 41 ++++++++----------------------- 2 files changed, 12 insertions(+), 33 deletions(-) diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index 907f55960ba8..4747ad48b3cc 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -761,8 +761,8 @@ struct netvsc_device { u32 max_chn; u32 num_chn; - spinlock_t sc_lock; /* Protects num_sc_offered variable */ - u32 num_sc_offered; + + refcount_t sc_offered; /* Holds rndis device info */ void *extension; diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index d193d549cec6..3bd5447277ad 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -997,7 +997,6 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc) struct netvsc_device *nvscdev = net_device_to_netvsc_device(ndev); u16 chn_index = new_sc->offermsg.offer.sub_channel_index; struct netvsc_channel *nvchan; - unsigned long flags; int ret; if (chn_index >= nvscdev->num_chn) @@ -1019,10 +1018,7 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc) napi_enable(&nvchan->napi); - spin_lock_irqsave(&nvscdev->sc_lock, flags); - nvscdev->num_sc_offered--; - spin_unlock_irqrestore(&nvscdev->sc_lock, flags); - if (nvscdev->num_sc_offered == 0) + if (refcount_dec_and_test(&nvscdev->sc_offered)) complete(&nvscdev->channel_init_wait); } @@ -1039,12 +1035,9 @@ int rndis_filter_device_add(struct hv_device *dev, struct ndis_recv_scale_cap rsscap; u32 rsscap_size = sizeof(struct ndis_recv_scale_cap); unsigned int gso_max_size = GSO_MAX_SIZE; - u32 mtu, size; - u32 num_rss_qs; - u32 sc_delta; + u32 mtu, size, num_rss_qs; const struct cpumask *node_cpu_mask; u32 num_possible_rss_qs; - unsigned long flags; int i, ret; rndis_device = get_rndis_device(); @@ -1067,7 +1060,7 @@ int rndis_filter_device_add(struct hv_device *dev, net_device->max_chn = 1; net_device->num_chn = 1; - spin_lock_init(&net_device->sc_lock); + refcount_set(&net_device->sc_offered, 0); net_device->extension = rndis_device; rndis_device->ndev = net; @@ -1204,6 +1197,7 @@ int rndis_filter_device_add(struct hv_device *dev, if (num_rss_qs == 0) return 0; + refcount_set(&net_device->sc_offered, num_rss_qs); vmbus_set_sc_create_callback(dev->channel, netvsc_sc_open); init_packet = &net_device->channel_init_pkt; @@ -1219,32 +1213,23 @@ int rndis_filter_device_add(struct hv_device *dev, VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); if (ret) goto out; - wait_for_completion(&net_device->channel_init_wait); - if (init_packet->msg.v5_msg.subchn_comp.status != - NVSP_STAT_SUCCESS) { + if (init_packet->msg.v5_msg.subchn_comp.status != NVSP_STAT_SUCCESS) { ret = -ENODEV; goto out; } + wait_for_completion(&net_device->channel_init_wait); + net_device->num_chn = 1 + init_packet->msg.v5_msg.subchn_comp.num_subchannels; - ret = rndis_filter_set_rss_param(rndis_device, netvsc_hash_key, - net_device->num_chn); - - /* - * Set the number of sub-channels to be received. - */ - spin_lock_irqsave(&net_device->sc_lock, flags); - sc_delta = num_rss_qs - (net_device->num_chn - 1); - net_device->num_sc_offered -= sc_delta; - spin_unlock_irqrestore(&net_device->sc_lock, flags); - + /* ignore failues from setting rss parameters, still have channels */ + rndis_filter_set_rss_param(rndis_device, netvsc_hash_key, + net_device->num_chn); out: if (ret) { net_device->max_chn = 1; net_device->num_chn = 1; - net_device->num_sc_offered = 0; } return 0; /* return 0 because primary channel can be used alone */ @@ -1259,12 +1244,6 @@ void rndis_filter_device_remove(struct hv_device *dev, { struct rndis_device *rndis_dev = net_dev->extension; - /* If not all subchannel offers are complete, wait for them until - * completion to avoid race. - */ - if (net_dev->num_sc_offered > 0) - wait_for_completion(&net_dev->channel_init_wait); - /* Halt and release the rndis device */ rndis_filter_halt_device(rndis_dev);