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Groups > linux.kernel > #1579608
| From | Peter Zijlstra <peterz@infradead.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function |
| Date | 2017-02-13 12:00 +0100 |
| Message-ID | <tamwq-2Cb-11@gated-at.bofh.it> (permalink) |
| References | <t9lM5-5lR-5@gated-at.bofh.it> <t9mf8-5Nv-21@gated-at.bofh.it> <t9mRR-6is-25@gated-at.bofh.it> <t9mRQ-6is-23@gated-at.bofh.it> <tammL-2yB-43@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Mon, Feb 13, 2017 at 11:47:16AM +0100, Peter Zijlstra wrote:
> That way we'd end up with something like:
>
> asm("
> push %rdi;
> movslq %edi, %rdi;
> movq __per_cpu_offset(,%rdi,8), %rax;
> cmpb $0, %[offset](%rax);
> setne %al;
> pop %rdi;
> " : : [offset] "i" (((unsigned long)&steal_time) + offsetof(struct steal_time, preempted)));
>
> And if we could get rid of the sign extend on edi we could avoid all the
> push-pop nonsense, but I'm not sure I see how to do that (then again,
> this asm foo isn't my strongest point).
Maybe:
movsql %edi, %rax;
movq __per_cpu_offset(,%rax,8), %rax;
cmpb $0, %[offset](%rax);
setne %al;
?
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[PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-10 17:00 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Paolo Bonzini <pbonzini@redhat.com> - 2017-02-10 17:30 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-10 17:30 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-10 18:10 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-13 11:50 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-13 12:00 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-13 20:50 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-13 21:20 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-13 23:00 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function hpa@zytor.com - 2017-02-13 23:10 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function hpa@zytor.com - 2017-02-13 23:20 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-13 23:40 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function hpa@zytor.com - 2017-02-13 23:50 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-14 10:50 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-14 15:50 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-14 17:10 +0100
Re: [Xen-devel] [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Andrew Cooper <andrew.cooper3@citrix.com> - 2017-02-14 17:20 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function hpa@zytor.com - 2017-02-13 21:20 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-13 23:00 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-13 23:30 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Peter Zijlstra <peterz@infradead.org> - 2017-02-13 23:40 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-13 20:50 +0100
Re: [PATCH v2] x86/paravirt: Don't make vcpu_is_preempted() a callee-save function Waiman Long <longman@redhat.com> - 2017-02-10 19:10 +0100
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