Commit 33b1e95c authored by Keith Busch's avatar Keith Busch Committed by Matthew Wilcox
Browse files

NVMe: CPU hot plug notification 



Registers with hot cpu notification to rebalance, and potentially allocate
additional, io queues.

Signed-off-by: default avatarKeith Busch <keith.busch@intel.com>
Signed-off-by: default avatarMatthew Wilcox <matthew.r.wilcox@intel.com>
parent 42f61420

drivers/block/nvme-core.c

+19 −0
Original line number Diff line number Diff line
@@ -2002,6 +2002,19 @@ static size_t db_bar_size(struct nvme_dev *dev, unsigned nr_io_queues) 
	return 4096 + ((nr_io_queues + 1) * 8 * dev->db_stride);

}



static int nvme_cpu_notify(struct notifier_block *self,

				unsigned long action, void *hcpu)

{

	struct nvme_dev *dev = container_of(self, struct nvme_dev, nb);

	switch (action) {

	case CPU_ONLINE:

	case CPU_DEAD:

		nvme_assign_io_queues(dev);

		break;

	}

	return NOTIFY_OK;

}



static int nvme_setup_io_queues(struct nvme_dev *dev)

{

	struct nvme_queue *adminq = raw_nvmeq(dev, 0);
@@ -2080,6 +2093,11 @@ static int nvme_setup_io_queues(struct nvme_dev *dev) 
	nvme_free_queues(dev, nr_io_queues + 1);

	nvme_assign_io_queues(dev);



	dev->nb.notifier_call = &nvme_cpu_notify;

	result = register_hotcpu_notifier(&dev->nb);

	if (result)

		goto free_queues;



	return 0;



 free_queues:
@@ -2357,6 +2375,7 @@ static void nvme_dev_shutdown(struct nvme_dev *dev) 
	int i;



	dev->initialized = 0;

	unregister_hotcpu_notifier(&dev->nb);



	spin_lock(&dev_list_lock);

	list_del_init(&dev->node);

include/linux/nvme.h

+1 −0
Original line number Diff line number Diff line
@@ -92,6 +92,7 @@ struct nvme_dev { 
	struct kref kref;

	struct miscdevice miscdev;

	struct work_struct reset_work;

	struct notifier_block nb;

	char name[12];

	char serial[20];

	char model[40];