From a71f938f3a9a7bc879296cd34ecae9effe5edf3f Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Mon, 20 Jul 2015 09:24:32 -0500 Subject: [PATCH] PCI: Stop caching ATS Invalidate Queue Depth Stop caching the Invalidate Queue Depth in struct pci_dev. pci_ats_queue_depth() is typically called only once per device, and it returns a fixed value per-device, so callers who need the value frequently can cache it themselves. Signed-off-by: Bjorn Helgaas Reviewed-by: Joerg Roedel --- drivers/pci/ats.c | 9 ++++----- include/linux/pci.h | 1 - 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c index 9355f754c7c2..ceda7dc556d4 100644 --- a/drivers/pci/ats.c +++ b/drivers/pci/ats.c @@ -20,16 +20,12 @@ void pci_ats_init(struct pci_dev *dev) { int pos; - u16 cap; pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS); if (!pos) return; dev->ats_cap = pos; - pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CAP, &cap); - dev->ats_qdep = PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) : - PCI_ATS_MAX_QDEP; } /** @@ -131,13 +127,16 @@ EXPORT_SYMBOL_GPL(pci_restore_ats_state); */ int pci_ats_queue_depth(struct pci_dev *dev) { + u16 cap; + if (!dev->ats_cap) return -EINVAL; if (dev->is_virtfn) return 0; - return dev->ats_qdep; + pci_read_config_word(dev, dev->ats_cap + PCI_ATS_CAP, &cap); + return PCI_ATS_CAP_QDEP(cap) ? PCI_ATS_CAP_QDEP(cap) : PCI_ATS_MAX_QDEP; } EXPORT_SYMBOL_GPL(pci_ats_queue_depth); diff --git a/include/linux/pci.h b/include/linux/pci.h index 307f96a58e8b..4b484fdfd66f 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -378,7 +378,6 @@ struct pci_dev { }; u16 ats_cap; /* ATS Capability offset */ u8 ats_stu; /* ATS Smallest Translation Unit */ - u8 ats_qdep; /* ATS Invalidate Queue Depth */ atomic_t ats_ref_cnt; /* number of VFs with ATS enabled */ #endif phys_addr_t rom; /* Physical address of ROM if it's not from the BAR */