diff options
Diffstat (limited to 'drivers/hv')
| -rw-r--r-- | drivers/hv/channel_mgmt.c | 47 | ||||
| -rw-r--r-- | drivers/hv/hv.c | 7 |
2 files changed, 38 insertions, 16 deletions
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index a19dc28fdf77..2db3823f0e59 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -18,6 +18,7 @@ #include <linux/module.h> #include <linux/completion.h> #include <linux/delay.h> +#include <linux/cpu.h> #include <linux/hyperv.h> #include <asm/mshyperv.h> @@ -466,13 +467,8 @@ static void vmbus_add_channel_work(struct work_struct *work) container_of(work, struct vmbus_channel, add_channel_work); struct vmbus_channel *primary_channel = newchannel->primary_channel; unsigned long flags; - u16 dev_type; int ret; - dev_type = hv_get_dev_type(newchannel); - - init_vp_index(newchannel, dev_type); - /* * This state is used to indicate a successful open * so that when we do close the channel normally, we @@ -504,7 +500,7 @@ static void vmbus_add_channel_work(struct work_struct *work) if (!newchannel->device_obj) goto err_deq_chan; - newchannel->device_obj->device_id = dev_type; + newchannel->device_obj->device_id = hv_get_dev_type(newchannel); /* * Add the new device to the bus. This will kick off device-driver * binding which eventually invokes the device driver's AddDevice() @@ -560,6 +556,25 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel) unsigned long flags; bool fnew = true; + /* + * Initialize the target_CPU before inserting the channel in + * the chn_list and sc_list lists, within the channel_mutex + * critical section: + * + * CPU1 CPU2 + * + * [vmbus_process_offer()] [hv_syninc_cleanup()] + * + * STORE target_cpu LOCK channel_mutex + * LOCK channel_mutex SEARCH chn_list + * INSERT chn_list LOAD target_cpu + * UNLOCK channel_mutex UNLOCK channel_mutex + * + * Forbids: CPU2's SEARCH from seeing CPU1's INSERT && + * CPU2's LOAD from *not* seing CPU1's STORE + */ + init_vp_index(newchannel, hv_get_dev_type(newchannel)); + mutex_lock(&vmbus_connection.channel_mutex); /* Remember the channels that should be cleaned up upon suspend. */ @@ -656,7 +671,7 @@ static DEFINE_SPINLOCK(bind_channel_to_cpu_lock); * channel interrupt load by binding a channel to VCPU. * * For pre-win8 hosts or non-performance critical channels we assign the - * first CPU in the first NUMA node. + * VMBUS_CONNECT_CPU. * * Starting with win8, performance critical channels will be distributed * evenly among all the available NUMA nodes. Once the node is assigned, @@ -675,17 +690,22 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) !alloc_cpumask_var(&available_mask, GFP_KERNEL)) { /* * Prior to win8, all channel interrupts are - * delivered on cpu 0. + * delivered on VMBUS_CONNECT_CPU. * Also if the channel is not a performance critical - * channel, bind it to cpu 0. - * In case alloc_cpumask_var() fails, bind it to cpu 0. + * channel, bind it to VMBUS_CONNECT_CPU. + * In case alloc_cpumask_var() fails, bind it to + * VMBUS_CONNECT_CPU. */ - channel->numa_node = 0; - channel->target_cpu = 0; - channel->target_vp = hv_cpu_number_to_vp_number(0); + channel->numa_node = cpu_to_node(VMBUS_CONNECT_CPU); + channel->target_cpu = VMBUS_CONNECT_CPU; + channel->target_vp = + hv_cpu_number_to_vp_number(VMBUS_CONNECT_CPU); return; } + /* No CPUs can come up or down during this. */ + cpus_read_lock(); + /* * Serializes the accesses to the global variable next_numa_node_id. * See also the header comment of the spin lock declaration. @@ -723,6 +743,7 @@ static void init_vp_index(struct vmbus_channel *channel, u16 dev_type) channel->target_vp = hv_cpu_number_to_vp_number(target_cpu); spin_unlock(&bind_channel_to_cpu_lock); + cpus_read_unlock(); free_cpumask_var(available_mask); } diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c index 17bf1f229152..188b42b07f07 100644 --- a/drivers/hv/hv.c +++ b/drivers/hv/hv.c @@ -256,9 +256,10 @@ int hv_synic_cleanup(unsigned int cpu) /* * Search for channels which are bound to the CPU we're about to - * cleanup. In case we find one and vmbus is still connected we need to - * fail, this will effectively prevent CPU offlining. There is no way - * we can re-bind channels to different CPUs for now. + * cleanup. In case we find one and vmbus is still connected, we + * fail; this will effectively prevent CPU offlining. + * + * TODO: Re-bind the channels to different CPUs. */ mutex_lock(&vmbus_connection.channel_mutex); list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) { |