From 5fd13460af36f5c6c958165d697950e676fad7c6 Mon Sep 17 00:00:00 2001 From: Sam Bobroff Date: Mon, 19 Mar 2018 13:48:55 +1100 Subject: [PATCH] powerpc/eeh: Clarify arguments to eeh_reset_device() It is currently difficult to understand the behaviour of eeh_reset_device() due to the way it's parameters are used. In particular, when 'bus' is NULL, it's value is still necessary so the same value is looked up again locally under a different name ('frozen_bus') but behaviour is changed. To clarify this, add a new parameter 'driver_eeh_aware', and have the caller set it when it would have passed NULL for 'bus' and always pass a value for 'bus'. Then change any test that was on 'bus' to one on '!driver_eeh_aware' and replace uses of 'frozen_bus' with 'bus'. Also update the function's comment. This should not change behaviour. Signed-off-by: Sam Bobroff Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/eeh_driver.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/arch/powerpc/kernel/eeh_driver.c b/arch/powerpc/kernel/eeh_driver.c index cb584d72b0a5..07437d765434 100644 --- a/arch/powerpc/kernel/eeh_driver.c +++ b/arch/powerpc/kernel/eeh_driver.c @@ -619,17 +619,19 @@ int eeh_pe_reset_and_recover(struct eeh_pe *pe) /** * eeh_reset_device - Perform actual reset of a pci slot + * @driver_eeh_aware: Does the device's driver provide EEH support? * @pe: EEH PE * @bus: PCI bus corresponding to the isolcated slot + * @rmv_data: Optional, list to record removed devices * * This routine must be called to do reset on the indicated PE. * During the reset, udev might be invoked because those affected * PCI devices will be removed and then added. */ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, - struct eeh_rmv_data *rmv_data) + struct eeh_rmv_data *rmv_data, + bool driver_eeh_aware) { - struct pci_bus *frozen_bus = eeh_pe_bus_get(pe); time64_t tstamp; int cnt, rc; struct eeh_dev *edev; @@ -645,7 +647,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, * into pci_hp_add_devices(). */ eeh_pe_state_mark(pe, EEH_PE_KEEP); - if (bus) { + if (!driver_eeh_aware) { if (pe->type & EEH_PE_VF) { eeh_pe_dev_traverse(pe, eeh_rmv_device, NULL); } else { @@ -653,7 +655,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, pci_hp_remove_devices(bus); pci_unlock_rescan_remove(); } - } else if (frozen_bus) { + } else if (bus) { eeh_pe_dev_traverse(pe, eeh_rmv_device, rmv_data); } @@ -689,7 +691,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, * the device up before the scripts have taken it down, * potentially weird things happen. */ - if (bus) { + if (!driver_eeh_aware) { pr_info("EEH: Sleep 5s ahead of complete hotplug\n"); ssleep(5); @@ -706,7 +708,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, eeh_pe_state_clear(pe, EEH_PE_PRI_BUS); pci_hp_add_devices(bus); } - } else if (frozen_bus && rmv_data->removed) { + } else if (bus && rmv_data->removed) { pr_info("EEH: Sleep 5s ahead of partial hotplug\n"); ssleep(5); @@ -715,7 +717,7 @@ static int eeh_reset_device(struct eeh_pe *pe, struct pci_bus *bus, if (pe->type & EEH_PE_VF) eeh_add_virt_device(edev, NULL); else - pci_hp_add_devices(frozen_bus); + pci_hp_add_devices(bus); } eeh_pe_state_clear(pe, EEH_PE_KEEP); @@ -820,7 +822,7 @@ void eeh_handle_normal_event(struct eeh_pe *pe) */ if (result == PCI_ERS_RESULT_NONE) { pr_info("EEH: Reset with hotplug activity\n"); - rc = eeh_reset_device(pe, bus, NULL); + rc = eeh_reset_device(pe, bus, NULL, false); if (rc) { pr_warn("%s: Unable to reset, err=%d\n", __func__, rc); @@ -872,7 +874,7 @@ void eeh_handle_normal_event(struct eeh_pe *pe) /* If any device called out for a reset, then reset the slot */ if (result == PCI_ERS_RESULT_NEED_RESET) { pr_info("EEH: Reset without hotplug activity\n"); - rc = eeh_reset_device(pe, NULL, &rmv_data); + rc = eeh_reset_device(pe, bus, &rmv_data, true); if (rc) { pr_warn("%s: Cannot reset, err=%d\n", __func__, rc); -- 2.30.2