Re: [PATCH v7 34/50] powerpc/pci: Delay populating pdn

Alexey Kardashevskiy
2015-11-18T04:24:44Z

On 11/05/2015 12:12 AM, Gavin Shan wrote:
> The pdn (struct pci_dn) instances are allocated from memblock or
> bootmem when creating PCI controller (hoses) in setup_arch(). PCI
> hotplug, which will be supported by proceeding patches, release
> PCI device nodes and their corresponding pdn on unplugging event.
> The memory chunks for pdn instances allocated from memblock or
> bootmem are hard to reused after being released.
>
> This delays creating pdn in core_initcall_sync(eeh_dev_phb_init) so
> that they are allocated from slab. In turn, the memory chunks for
> them can be reused after being released without problem. Since the
> pdn and eeh_dev has same life cycle, the eeh_dev is created when
> pdn is populated. We needn't create eeh_dev with another initcall.
> The time to create PHB PEs is delayed a bit from core_initcall() to
> core_initcall_sync().

Why is delayed? I mean what needs to be called before eeh_dev_phb_init()?

>
> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
> ---
> arch/powerpc/include/asm/eeh.h | 2 +-
> arch/powerpc/include/asm/ppc-pci.h | 2 --
> arch/powerpc/kernel/eeh_dev.c | 19 ++++-------------
> arch/powerpc/kernel/pci_dn.c | 20 ++++++++++++++++--
> arch/powerpc/platforms/maple/pci.c | 34 ++++++++++++++++++------------
> arch/powerpc/platforms/pasemi/pci.c | 3 ---
> arch/powerpc/platforms/powermac/pci.c | 38 +++++++++++++++++++++-------------
> arch/powerpc/platforms/powernv/pci.c | 3 ---
> arch/powerpc/platforms/pseries/setup.c | 6 +-----
> 9 files changed, 69 insertions(+), 58 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
> index c5eb86f..27352f4 100644
> --- a/arch/powerpc/include/asm/eeh.h
> +++ b/arch/powerpc/include/asm/eeh.h
> @@ -268,7 +268,7 @@ void eeh_pe_restore_bars(struct eeh_pe *pe);
> const char *eeh_pe_loc_get(struct eeh_pe *pe);
> struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe);
>
> -void *eeh_dev_init(struct pci_dn *pdn, void *data);
> +struct eeh_dev *eeh_dev_init(struct pci_dn *pdn);
> void eeh_dev_phb_init_dynamic(struct pci_controller *phb);
> int eeh_init(void);
> int __init eeh_ops_register(struct eeh_ops *ops);
> diff --git a/arch/powerpc/include/asm/ppc-pci.h b/arch/powerpc/include/asm/ppc-pci.h
> index 8753e4e..0f73de0 100644
> --- a/arch/powerpc/include/asm/ppc-pci.h
> +++ b/arch/powerpc/include/asm/ppc-pci.h
> @@ -39,8 +39,6 @@ void *pci_traverse_device_nodes(struct device_node *start,
> void *traverse_pci_dn(struct pci_dn *root,
> void *(*fn)(struct pci_dn *, void *),
> void *data);
> -
> -extern void pci_devs_phb_init(void);
> extern void pci_devs_phb_init_dynamic(struct pci_controller *phb);
>
> /* From rtas_pci.h */
> diff --git a/arch/powerpc/kernel/eeh_dev.c b/arch/powerpc/kernel/eeh_dev.c
> index aabba94..1c4bc35 100644
> --- a/arch/powerpc/kernel/eeh_dev.c
> +++ b/arch/powerpc/kernel/eeh_dev.c
> @@ -44,14 +44,13 @@
> /**
> * eeh_dev_init - Create EEH device according to OF node
> * @pdn: PCI device node
> - * @data: PHB
> *
> * It will create EEH device according to the given OF node. The function
> * might be called by PCI emunation, DR, PHB hotplug.
> */
> -void *eeh_dev_init(struct pci_dn *pdn, void *data)
> +struct eeh_dev *eeh_dev_init(struct pci_dn *pdn)
> {
> - struct pci_controller *phb = data;
> + struct pci_controller *phb = pdn->phb;
> struct eeh_dev *edev;
>
> /* Allocate EEH device */
> @@ -68,7 +67,7 @@ void *eeh_dev_init(struct pci_dn *pdn, void *data)
> edev->phb = phb;
> INIT_LIST_HEAD(&edev->list);
>
> - return NULL;
> + return edev;
> }
>
> /**
> @@ -80,16 +79,8 @@ void *eeh_dev_init(struct pci_dn *pdn, void *data)
> */
> void eeh_dev_phb_init_dynamic(struct pci_controller *phb)
> {
> - struct pci_dn *root = phb->pci_data;
> -
> /* EEH PE for PHB */
> eeh_phb_pe_create(phb);
> -
> - /* EEH device for PHB */
> - eeh_dev_init(root, phb);
> -
> - /* EEH devices for children OF nodes */
> - traverse_pci_dn(root, eeh_dev_init, phb);
> }
>
> /**
> @@ -105,9 +96,7 @@ static int __init eeh_dev_phb_init(void)
> list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
> eeh_dev_phb_init_dynamic(phb);
>
> - pr_info("EEH: devices created\n");
> -
> return 0;
> }
>
> -core_initcall(eeh_dev_phb_init);
> +core_initcall_sync(eeh_dev_phb_init);

May be remove core_initcall_sync and call eeh_dev_phb_init_dynamic()
directly from the loop in pci_devs_phb_init()?

> diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c
> index aa4110f..581612c 100644
> --- a/arch/powerpc/kernel/pci_dn.c
> +++ b/arch/powerpc/kernel/pci_dn.c
> @@ -272,8 +272,11 @@ struct pci_dn *pci_add_device_node_info(struct pci_controller *hose,
> const __be32 *regs;
> struct device_node *parent;
> struct pci_dn *pdn;
> +#ifdef CONFIG_EEH
> + struct eeh_dev *edev;
> +#endif
>
> - pdn = zalloc_maybe_bootmem(sizeof(*pdn), GFP_KERNEL);
> + pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
> if (pdn == NULL)
> return NULL;
> dn->data = pdn;
> @@ -302,6 +305,15 @@ struct pci_dn *pci_add_device_node_info(struct pci_controller *hose,
> /* Extended config space */
> pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);
>
> + /* Create EEH device */
> +#ifdef CONFIG_EEH
> + edev = eeh_dev_init(pdn);
> + if (!edev) {
> + kfree(pdn);
> + return NULL;
> + }
> +#endif
> +
> /* Attach to parent node */
> INIT_LIST_HEAD(&pdn->child_list);
> INIT_LIST_HEAD(&pdn->list);
> @@ -486,15 +498,19 @@ void pci_devs_phb_init_dynamic(struct pci_controller *phb)
> * pci device found underneath. This routine runs once,
> * early in the boot sequence.
> */
> -void __init pci_devs_phb_init(void)
> +static int __init pci_devs_phb_init(void)
> {
> struct pci_controller *phb, *tmp;
>
> /* This must be done first so the device nodes have valid pci info! */
> list_for_each_entry_safe(phb, tmp, &hose_list, list_node)
> pci_devs_phb_init_dynamic(phb);
> +
> + return 0;
> }
>
> +core_initcall(pci_devs_phb_init);
> +
> static void pci_dev_pdn_setup(struct pci_dev *pdev)
> {
> struct pci_dn *pdn;
> diff --git a/arch/powerpc/platforms/maple/pci.c b/arch/powerpc/platforms/maple/pci.c
> index a923230..a2f89e6 100644
> --- a/arch/powerpc/platforms/maple/pci.c
> +++ b/arch/powerpc/platforms/maple/pci.c
> @@ -568,6 +568,26 @@ void maple_pci_irq_fixup(struct pci_dev *dev)
> DBG(" <- maple_pci_irq_fixup\n");
> }
>
> +static int maple_pci_root_bridge_prepare(struct pci_host_bridge *bridge)
> +{
> + struct pci_controller *hose = pci_bus_to_host(bridge->bus);
> + struct device_node *np, *child;
> +
> + if (hose != u3_agp)
> + return 0;
> +
> + /* Fixup the PCI<->OF mapping for U3 AGP due to bus renumbering. We
> + * assume there is no P2P bridge on the AGP bus, which should be a
> + * safe assumptions hopefully.
> + */
> + np = hose->dn;
> + PCI_DN(np)->busno = 0xf0;
> + for_each_child_of_node(np, child)
> + PCI_DN(child)->busno = 0xf0;
> +
> + return 0;
> +}
> +
> void __init maple_pci_init(void)
> {
> struct device_node *np, *root;
> @@ -605,19 +625,7 @@ void __init maple_pci_init(void)
> if (ht && maple_add_bridge(ht) != 0)
> of_node_put(ht);
>
> - /* Setup the linkage between OF nodes and PHBs */
> - pci_devs_phb_init();
> -
> - /* Fixup the PCI<->OF mapping for U3 AGP due to bus renumbering. We
> - * assume there is no P2P bridge on the AGP bus, which should be a
> - * safe assumptions hopefully.
> - */
> - if (u3_agp) {
> - struct device_node *np = u3_agp->dn;
> - PCI_DN(np)->busno = 0xf0;
> - for (np = np->child; np; np = np->sibling)
> - PCI_DN(np)->busno = 0xf0;
> - }
> + ppc_md.pcibios_root_bridge_prepare = maple_pci_root_bridge_prepare;

This seems an unrelated change.

What is this pcibios_root_bridge_prepare()? How come you do not need one
for the powernv platform but do need for others? Same question about powermac.

>
> /* Tell pci.c to not change any resource allocations. */
> pci_add_flags(PCI_PROBE_ONLY);
> diff --git a/arch/powerpc/platforms/pasemi/pci.c b/arch/powerpc/platforms/pasemi/pci.c
> index f3a68a0..10c4e8f 100644
> --- a/arch/powerpc/platforms/pasemi/pci.c
> +++ b/arch/powerpc/platforms/pasemi/pci.c
> @@ -229,9 +229,6 @@ void __init pas_pci_init(void)
> of_node_get(np);
>
> of_node_put(root);
> -
> - /* Setup the linkage between OF nodes and PHBs */
> - pci_devs_phb_init();
> }
>
> void __iomem *pasemi_pci_getcfgaddr(struct pci_dev *dev, int offset)
> diff --git a/arch/powerpc/platforms/powermac/pci.c b/arch/powerpc/platforms/powermac/pci.c
> index 59ab16f..6e06c3b 100644
> --- a/arch/powerpc/platforms/powermac/pci.c
> +++ b/arch/powerpc/platforms/powermac/pci.c
> @@ -878,6 +878,29 @@ void pmac_pci_irq_fixup(struct pci_dev *dev)
> #endif /* CONFIG_PPC32 */
> }
>
> +#ifdef CONFIG_PPC64
> +static int pmac_pci_root_bridge_prepare(struct pci_host_bridge *bridge)
> +{
> + struct pci_controller *hose = pci_bus_to_host(bridge->bus);
> + struct device_node *np, *child;
> +
> + if (hose != u3_agp)
> + return 0;
> +
> + /* Fixup the PCI<->OF mapping for U3 AGP due to bus renumbering. We
> + * assume there is no P2P bridge on the AGP bus, which should be a
> + * safe assumptions for now. We should do something better in the
> + * future though
> + */
> + np = hose->dn;
> + PCI_DN(np)->busno = 0xf0;
> + for_each_child_of_node(np, child)
> + PCI_DN(child)->busno = 0xf0;
> +
> + return 0;
> +}
> +#endif /* CONFIG_PPC64 */
> +
> void __init pmac_pci_init(void)
> {
> struct device_node *np, *root;
> @@ -914,20 +937,7 @@ void __init pmac_pci_init(void)
> if (ht && pmac_add_bridge(ht) != 0)
> of_node_put(ht);
>
> - /* Setup the linkage between OF nodes and PHBs */
> - pci_devs_phb_init();
> -
> - /* Fixup the PCI<->OF mapping for U3 AGP due to bus renumbering. We
> - * assume there is no P2P bridge on the AGP bus, which should be a
> - * safe assumptions for now. We should do something better in the
> - * future though
> - */
> - if (u3_agp) {
> - struct device_node *np = u3_agp->dn;
> - PCI_DN(np)->busno = 0xf0;
> - for (np = np->child; np; np = np->sibling)
> - PCI_DN(np)->busno = 0xf0;
> - }
> + ppc_md.pcibios_root_bridge_prepare = pmac_pci_root_bridge_prepare;
> /* pmac_check_ht_link(); */
>
> #else /* CONFIG_PPC64 */
> diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
> index fa99daf..d8832ea 100644
> --- a/arch/powerpc/platforms/powernv/pci.c
> +++ b/arch/powerpc/platforms/powernv/pci.c
> @@ -807,9 +807,6 @@ void __init pnv_pci_init(void)
> for_each_compatible_node(np, NULL, "ibm,ioda2-phb")
> pnv_pci_init_ioda2_phb(np);
>
> - /* Setup the linkage between OF nodes and PHBs */
> - pci_devs_phb_init();
> -
> /* Configure IOMMU DMA hooks */
> set_pci_dma_ops(&dma_iommu_ops);
> }
> diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
> index 6c274cb..bdf93a1 100644
> --- a/arch/powerpc/platforms/pseries/setup.c
> +++ b/arch/powerpc/platforms/pseries/setup.c
> @@ -262,11 +262,8 @@ static int pci_dn_reconfig_notifier(struct notifier_block *nb, unsigned long act
> case OF_RECONFIG_ATTACH_NODE:
> parent = of_get_parent(np);
> pdn = parent ? PCI_DN(parent) : NULL;
> - if (pdn) {
> - /* Create pdn and EEH device */
> + if (pdn)
> pci_add_device_node_info(pdn->phb, np);
> - eeh_dev_init(PCI_DN(np), pdn->phb);
> - }
>
> of_node_put(parent);
> break;
> @@ -489,7 +486,6 @@ static void __init find_and_init_phbs(void)
> }
>
> of_node_put(root);
> - pci_devs_phb_init();
>
> /*
> * PCI_PROBE_ONLY and PCI_REASSIGN_ALL_BUS can be set via properties
>

--
Alexey