Alex Williamson e309df5b0c vfio/pci: Parallelize device open and release ... In commit 61d792562b ("vfio-pci: Use mutex around open, release, and remove") a mutex was added to freeze the refcnt for a device so that we can handle errors and perform bus resets on final close. However, bus resets can be rather slow and a global mutex here is undesirable. Evaluating the potential locking granularity, a per-device mutex provides the best resolution but with multiple devices on a bus all released concurrently, they'll race to acquire each other's mutex, likely resulting in no reset at all if we use trylock. We therefore lock at the granularity of the bus/slot reset as we're only attempting a single reset for this group of devices anyway. This allows much greater scaling as we're bounded in the number of devices protected by a single reflck object. Reported-by: Christian Ehrhardt <christian.ehrhardt@canonical.com> Tested-by: Christian Ehrhardt <christian.ehrhardt@canonical.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>		2018-12-12 12:51:07 -07:00
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Kconfig	vfio/pci: Make IGD support a configurable option	2018-06-18 16:39:50 -06:00
Makefile	vfio/pci: Intel IGD OpRegion support	2016-02-22 16:10:09 -07:00
vfio_pci_config.c	vfio/pci: Mask buggy SR-IOV VF INTx support	2018-09-25 13:01:27 -06:00
vfio_pci_igd.c	vfio/pci: Intel IGD host and LCP bridge config space access	2016-02-22 16:10:09 -07:00
vfio_pci_intrs.c	vfio/pci: Fix integer overflows, bitmask check	2016-10-26 13:49:29 -06:00
vfio_pci_private.h	vfio/pci: Parallelize device open and release	2018-12-12 12:51:07 -07:00
vfio_pci_rdwr.c	vfio/pci: Add ioeventfd support	2018-03-26 13:22:58 -06:00
vfio_pci.c	vfio/pci: Parallelize device open and release	2018-12-12 12:51:07 -07:00