On Tue, 2018-09-18 at 17:58 -0600, Keith Busch wrote:
> This uses the managed device resource allocations for the service data
> so that the aer driver doesn't need to manage it, further simplifying
> this driver.
Just be careful (it migh be ok, I haven't audited everything, but I got
bitten by something like that in the past) that the devm stuff will get
disposed of in two cases:
- The owner device going away (so far so good)
- The owner device's driver being unbound
The latter is something not completely obvious, ie, even if the owner
device still has held references, the successful completion of
->remove() on the driver will be followed by a cleanup of the managed
stuff.
As I said, it might be ok in the AER case, but you might want to at
least keep the set_service_data(dev, NULL) to make sure you don't leave
a stale pointer there.
Cheers,
Ben.
> Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
> ---
> drivers/pci/pcie/aer.c | 17 +++++------------
> 1 file changed, 5 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index 1878d9d7760b..7ecad011458d 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -1366,11 +1366,7 @@ static void aer_remove(struct pcie_device *dev)
> {
> struct aer_rpc *rpc = get_service_data(dev);
>
> - if (rpc) {
> - aer_disable_rootport(rpc);
> - kfree(rpc);
> - set_service_data(dev, NULL);
> - }
> + aer_disable_rootport(rpc);
> }
>
> /**
> @@ -1383,10 +1379,9 @@ static int aer_probe(struct pcie_device *dev)
> {
> int status;
> struct aer_rpc *rpc;
> - struct device *device = &dev->port->device;
> + struct device *device = &dev->device;
>
> - /* Alloc rpc data structure */
> - rpc = kzalloc(sizeof(struct aer_rpc), GFP_KERNEL);
> + rpc = devm_kzalloc(device, sizeof(struct aer_rpc), GFP_KERNEL);
> if (!rpc) {
> dev_printk(KERN_DEBUG, device, "alloc AER rpc failed\n");
> return -ENOMEM;
> @@ -1394,13 +1389,11 @@ static int aer_probe(struct pcie_device *dev)
> rpc->rpd = dev->port;
> set_service_data(dev, rpc);
>
> - /* Request IRQ ISR */
> - status = request_threaded_irq(dev->irq, aer_irq, aer_isr,
> - IRQF_SHARED, "aerdrv", dev);
> + status = devm_request_threaded_irq(device, dev->irq, aer_irq, aer_isr,
> + IRQF_SHARED, "aerdrv", dev);
> if (status) {
> dev_printk(KERN_DEBUG, device, "request AER IRQ %d failed\n",
> dev->irq);
> - aer_remove(dev);
> return status;
> }
>
