From: Vaibhav Jain <vaibhav@linux.ibm.com>
To: linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org,
kvm-ppc@vger.kernel.org
Cc: mikey@neuling.org, sbhat@linux.ibm.com,
amachhiw@linux.vnet.ibm.com, Jordan Niethe <jniethe5@gmail.com>,
gautam@linux.ibm.com, Nicholas Piggin <npiggin@gmail.com>,
David.Laight@ACULAB.COM, kconsul@linux.vnet.ibm.com,
Vaibhav Jain <vaibhav@linux.ibm.com>,
Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Subject: [PATCH 12/12] KVM: PPC: Book3S HV nestedv2: Do not cancel pending decrementer exception
Date: Fri, 1 Dec 2023 18:56:17 +0530 [thread overview]
Message-ID: <20231201132618.555031-13-vaibhav@linux.ibm.com> (raw)
In-Reply-To: <20231201132618.555031-1-vaibhav@linux.ibm.com>
From: Jordan Niethe <jniethe5@gmail.com>
In the nestedv2 case, if there is a pending decrementer exception, the
L1 must get the L2's timebase from the L0 to see if the exception should
be cancelled. This adds the overhead of a H_GUEST_GET_STATE call to the
likely case in which the decrementer should not be cancelled.
Avoid this logic for the nestedv2 case.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
---
arch/powerpc/kvm/book3s_hv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 2ee3f2478570..e48126a59ba7 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -4834,7 +4834,7 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit,
* entering a nested guest in which case the decrementer is now owned
* by L2 and the L1 decrementer is provided in hdec_expires
*/
- if (kvmppc_core_pending_dec(vcpu) &&
+ if (!kvmhv_is_nestedv2() && kvmppc_core_pending_dec(vcpu) &&
((tb < kvmppc_dec_expires_host_tb(vcpu)) ||
(trap == BOOK3S_INTERRUPT_SYSCALL &&
kvmppc_get_gpr(vcpu, 3) == H_ENTER_NESTED)))
--
2.42.0
next prev parent reply other threads:[~2023-12-01 13:36 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-01 13:26 [PATCH 00/12] KVM: PPC: Nested APIv2 : Performance improvements Vaibhav Jain
2023-12-01 13:26 ` [PATCH 01/12] KVM: PPC: Book3S HV nestedv2: Invalidate RPT before deleting a guest Vaibhav Jain
2023-12-07 9:15 ` Aneesh Kumar K.V
2023-12-08 13:45 ` Vaibhav Jain
2023-12-15 16:12 ` Aneesh Kumar K.V
2023-12-18 4:54 ` Vaibhav Jain
2023-12-01 13:26 ` [PATCH 02/12] KVM: PPC: Book3S HV nestedv2: Avoid reloading the tb offset Vaibhav Jain
2023-12-01 13:26 ` [PATCH 03/12] KVM: PPC: Book3S HV nestedv2: Do not check msr on hcalls Vaibhav Jain
2023-12-01 13:26 ` [PATCH 04/12] KVM: PPC: Book3S HV nestedv2: Get the PID only if needed to copy tofrom a guest Vaibhav Jain
2023-12-01 13:26 ` [PATCH 05/12] KVM: PPC: Book3S HV nestedv2: Ensure LPCR_MER bit is passed to the L0 Vaibhav Jain
2023-12-01 13:26 ` [PATCH 06/12] KVM: PPC: Book3S HV: Handle pending exceptions on guest entry with MSR_EE Vaibhav Jain
2023-12-01 13:26 ` [PATCH 07/12] KVM: PPC: Book3S HV nestedv2: Do not inject certain interrupts Vaibhav Jain
2023-12-01 13:26 ` [PATCH 08/12] KVM: PPC: Book3S HV nestedv2: Avoid msr check in kvmppc_handle_exit_hv() Vaibhav Jain
2023-12-01 13:26 ` [PATCH 09/12] KVM: PPC: Book3S HV nestedv2: Do not call H_COPY_TOFROM_GUEST Vaibhav Jain
2023-12-08 8:15 ` Aneesh Kumar K.V
2023-12-11 3:56 ` Vaibhav Jain
2023-12-11 4:01 ` Aneesh Kumar K.V
2023-12-18 7:02 ` Vaibhav Jain
2023-12-18 7:29 ` Aneesh Kumar K.V
2023-12-01 13:26 ` [PATCH 10/12] KVM: PPC: Book3S HV nestedv2: Register the VPA with the L0 Vaibhav Jain
2023-12-01 13:26 ` [PATCH 11/12] KVM: PPC: Reduce reliance on analyse_instr() in mmio emulation Vaibhav Jain
2023-12-01 13:26 ` Vaibhav Jain [this message]
2023-12-21 10:44 ` [PATCH 00/12] KVM: PPC: Nested APIv2 : Performance improvements Michael Ellerman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20231201132618.555031-13-vaibhav@linux.ibm.com \
--to=vaibhav@linux.ibm.com \
--cc=David.Laight@ACULAB.COM \
--cc=amachhiw@linux.vnet.ibm.com \
--cc=gautam@linux.ibm.com \
--cc=jniethe5@gmail.com \
--cc=kconsul@linux.vnet.ibm.com \
--cc=kvm-ppc@vger.kernel.org \
--cc=kvm@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mikey@neuling.org \
--cc=npiggin@gmail.com \
--cc=sbhat@linux.ibm.com \
--cc=svaidy@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).