Re: [PATCH RFC V8 17/17] Documentation/kvm : Add documentation on Hypercalls and features used for PV spinlock

On 05/30/2012 05:24 PM, Jan Kiszka wrote:

On 2012-05-02 12:09, Raghavendra K T wrote:

quoted

From: Raghavendra K T<redacted>

KVM_HC_KICK_CPU  hypercall added to wakeup halted vcpu in paravirtual spinlock
enabled guest.

KVM_FEATURE_PV_UNHALT enables guest to check whether pv spinlock can be enabled
in guest.

Thanks Alex for KVM_HC_FEATURES inputs and Vatsa for rewriting KVM_HC_KICK_CPU

This contains valuable documentation for features that are already
supported. Can you break them out and post as separate patch already?
One comment on them below.

That sounds like a good idea. Sure, will do that.

quoted

Signed-off-by: Srivatsa Vaddagiri<redacted>
Signed-off-by: Raghavendra K T<redacted>
---
  Documentation/virtual/kvm/cpuid.txt      |    4 ++
  Documentation/virtual/kvm/hypercalls.txt |   60 ++++++++++++++++++++++++++++++
  2 files changed, 64 insertions(+), 0 deletions(-)

diff --git a/Documentation/virtual/kvm/cpuid.txt b/Documentation/virtual/kvm/cpuid.txt
index 8820685..062dff9 100644
--- a/Documentation/virtual/kvm/cpuid.txt
+++ b/Documentation/virtual/kvm/cpuid.txt

@@ -39,6 +39,10 @@ KVM_FEATURE_CLOCKSOURCE2           ||     3 || kvmclock available at msrs
  KVM_FEATURE_ASYNC_PF               ||     4 || async pf can be enabled by
                                     ||       || writing to msr 0x4b564d02
  ------------------------------------------------------------------------------
+KVM_FEATURE_PV_UNHALT              ||     6 || guest checks this feature bit
+                                   ||       || before enabling paravirtualized
+                                   ||       || spinlock support.
+------------------------------------------------------------------------------
  KVM_FEATURE_CLOCKSOURCE_STABLE_BIT ||    24 || host will warn if no guest-side
                                     ||       || per-cpu warps are expected in
                                     ||       || kvmclock.

diff --git a/Documentation/virtual/kvm/hypercalls.txt b/Documentation/virtual/kvm/hypercalls.txt
new file mode 100644
index 0000000..bc3f14a
--- /dev/null
+++ b/Documentation/virtual/kvm/hypercalls.txt

@@ -0,0 +1,60 @@
+KVM Hypercalls Documentation
+===========================
+The template for each hypercall is:
+1. Hypercall name, value.
+2. Architecture(s)
+3. Status (deprecated, obsolete, active)
+4. Purpose
+
+1. KVM_HC_VAPIC_POLL_IRQ
+------------------------
+Value: 1
+Architecture: x86
+Purpose: None

Purpose: Trigger guest exit so that the host can check for pending
interrupts on reentry.

will add fold this and resend.

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