Commit a71f938f authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

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: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ff9bee89

drivers/pci/ats.c

+4 −5
Original line number Diff line number Diff line
@@ -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);

include/linux/pci.h

+0 −1
Original line number Diff line number Diff line
@@ -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 */

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