Hi Ethan, On 9/24/20 9:34 PM, Ethan Zhao wrote:
When uncorrectable error happens, AER driver and DPC driver interrupt handlers likely call pcie_do_recovery()->pci_walk_bus()->report_frozen_detected() with pci_channel_io_frozen the same time. If pci_dev_set_io_state() return true even if the original state is pci_channel_io_frozen, that will cause AER or DPC handler re-enter the error detecting and recovery procedure one after another. The result is the recovery flow mixed between AER and DPC. So simplify the pci_dev_set_io_state() function to only return true when dev->error_state is changed. Signed-off-by: Ethan Zhao <haifeng.zhao@xxxxxxxxx> Tested-by: Wen jin <wen.jin@xxxxxxxxx> Tested-by: Shanshan Zhang <ShanshanX.Zhang@xxxxxxxxx> --- drivers/pci/pci.h | 31 +++---------------------------- 1 file changed, 3 insertions(+), 28 deletions(-) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index fa12f7cbc1a0..d420bb977f3b 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -362,35 +362,10 @@ static inline bool pci_dev_set_io_state(struct pci_dev *dev, bool changed = false;device_lock_assert(&dev->dev);- switch (new) { - case pci_channel_io_perm_failure: - switch (dev->error_state) { - case pci_channel_io_frozen: - case pci_channel_io_normal: - case pci_channel_io_perm_failure: - changed = true; - break; - } - break; - case pci_channel_io_frozen: - switch (dev->error_state) { - case pci_channel_io_frozen: - case pci_channel_io_normal: - changed = true; - break; - } - break; - case pci_channel_io_normal: - switch (dev->error_state) { - case pci_channel_io_frozen: - case pci_channel_io_normal: - changed = true; - break; - } - break; - } - if (changed) + if (dev->error_state != new) { dev->error_state = new; + changed = true; + } return changed; }
The flow is a lot easier to follow now. Thank you. Reviewed-by: Alexandru Gagniuc <mr.nuke.me@xxxxxxxxx>
