Re: [PATCH RT] vfio-pci: Set MSI/MSI-X ISR to non-threaded

2017-12-07 Thread Steven Rostedt
On Thu, 7 Dec 2017 01:27:03 + "Su, David W" wrote: > >And spin_lock() turns into a mutex in PREEMPT_RT, which means it can > >sleep. You can't sleep in hard interrupt context. This will eventually > >crash the kernel. > > Steve, thanks for your review and comment. > > I can think of 2 sce

RE: [PATCH RT] vfio-pci: Set MSI/MSI-X ISR to non-threaded

2017-12-06 Thread Su, David W
From: Steven Rostedt [mailto:rost...@goodmis.org] Sent: Thursday, November 30, 2017 6:09 PM > >On Thu, 30 Nov 2017 17:05:35 -0800 >David Su wrote: > >> Setting MSI/MSI-X ISR to be non-threaded will result in shorter and more >> deterministic IRQ delivery latencies to VFIO applications, because >>

Re: [PATCH RT] vfio-pci: Set MSI/MSI-X ISR to non-threaded

2017-11-30 Thread Steven Rostedt
On Thu, 30 Nov 2017 17:05:35 -0800 David Su wrote: > Setting MSI/MSI-X ISR to be non-threaded will result in shorter and more > deterministic IRQ delivery latencies to VFIO applications, because > context switches to the ISR thread are eliminated. This is important > for applications with low la