Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1494497

[PATCH RFC 0/5] x86,fpu: make FPU context switching much lazier

Show all headers | View raw

This series is an attempt at making the x86 FPU context switching
code much lazier.  By only reloading the FPU context when a task
switches to user mode, we can avoid switching FPU context for tasks
that spin in kernel mode, and avoid reloading the FPU context for
tasks that get interrupted by a kernel thread or briefly go idle.

It also allows us to skip restoring the userspace FPU context when
exiting a KVM guest.

This series is still BROKEN.  The first 3 patches seem to work
fine in my tests (but should not, due to missing signal path
code), while the 4th test makes it easier to trigger bugs.

I am posting this to ask about obvious issues people may see,
ideas on what direction I should take this series in, and to
avoid code conflicts with Andy's plans wrt. lazy fpu mode.

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

[PATCH RFC 0/5] x86,fpu: make FPU context switching much lazier riel@redhat.com - 2016-10-01 23:00 +0200
  [PATCH RFC 1/5] x86,fpu: split prev/next task fpu state handling riel@redhat.com - 2016-10-01 23:00 +0200
    Re: [PATCH RFC 1/5] x86,fpu: split prev/next task fpu state handling Andy Lutomirski <luto@amacapital.net> - 2016-10-02 01:30 +0200
      Re: [PATCH RFC 1/5] x86,fpu: split prev/next task fpu state  handling Rik van Riel <riel@redhat.com> - 2016-10-04 17:30 +0200

csiph-web