Commit 9cd0f6d5 authored by Reinette Chatre's avatar Reinette Chatre Committed by Alex Williamson
Browse files

vfio/pci: Use bitfield for struct vfio_pci_core_device flags 



struct vfio_pci_core_device contains eleven boolean flags.
Boolean flags clearly indicate their usage but space usage
starts to be a concern when there are many.

An upcoming change adds another boolean flag to
struct vfio_pci_core_device, thereby increasing the concern
that the boolean flags are consuming unnecessary space.

Transition the boolean flags to use bitfields. On a system that
uses one byte per boolean this reduces the space consumed
by existing flags from 11 bytes to 2 bytes with room for
a few more flags without increasing the structure's size.

Suggested-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarReinette Chatre <reinette.chatre@intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Acked-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/cf34bf0499c889554a8105eeb18cc0ab673005be.1683740667.git.reinette.chatre@intel.com


Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 9387cf59

include/linux/vfio_pci_core.h

+11 −11
Original line number Diff line number Diff line
@@ -68,17 +68,17 @@ struct vfio_pci_core_device { 
	u16			msix_size;

	u32			msix_offset;

	u32			rbar[7];

	bool			pci_2_3;

	bool			virq_disabled;

	bool			reset_works;

	bool			extended_caps;

	bool			bardirty;

	bool			has_vga;

	bool			needs_reset;

	bool			nointx;

	bool			needs_pm_restore;

	bool			pm_intx_masked;

	bool			pm_runtime_engaged;

	bool			pci_2_3:1;

	bool			virq_disabled:1;

	bool			reset_works:1;

	bool			extended_caps:1;

	bool			bardirty:1;

	bool			has_vga:1;

	bool			needs_reset:1;

	bool			nointx:1;

	bool			needs_pm_restore:1;

	bool			pm_intx_masked:1;

	bool			pm_runtime_engaged:1;

	struct pci_saved_state	*pci_saved_state;

	struct pci_saved_state	*pm_save;

	int			ioeventfds_nr;