kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Xu <peterx@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	peterx@redhat.com, Maxim Levitsky <mlevitsk@redhat.com>
Subject: [PATCH v2 4/9] KVM: X86: Introduce pte_list_count() helper
Date: Fri, 25 Jun 2021 11:32:09 -0400	[thread overview]
Message-ID: <20210625153214.43106-5-peterx@redhat.com> (raw)
In-Reply-To: <20210625153214.43106-1-peterx@redhat.com>

This helper is used to count the number of rmap entries in the rmap list
pointed by the kvm_rmap_head.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 arch/x86/kvm/mmu/mmu.c          | 21 +++++++++++++++++++++
 arch/x86/kvm/mmu/mmu_internal.h |  1 +
 2 files changed, 22 insertions(+)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index eb16c1dbbb32..b3f738a7c05e 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -990,6 +990,27 @@ static void pte_list_remove(struct kvm_rmap_head *rmap_head, u64 *sptep)
 	__pte_list_remove(sptep, rmap_head);
 }
 
+unsigned int pte_list_count(struct kvm_rmap_head *rmap_head)
+{
+	struct pte_list_desc *desc;
+	unsigned int i, count = 0;
+
+	if (!rmap_head->val)
+		return 0;
+	else if (!(rmap_head->val & 1))
+		return 1;
+
+	desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
+
+	while (desc) {
+		for (i = 0; (i < PTE_LIST_EXT) && desc->sptes[i]; i++)
+			count++;
+		desc = desc->more;
+	}
+
+	return count;
+}
+
 static struct kvm_rmap_head *__gfn_to_rmap(gfn_t gfn, int level,
 					   struct kvm_memory_slot *slot)
 {
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 35567293c1fd..325b4242deed 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -131,6 +131,7 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
 				    int min_level);
 void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
 					u64 start_gfn, u64 pages);
+unsigned int pte_list_count(struct kvm_rmap_head *rmap_head);
 
 /*
  * Return values of handle_mmio_page_fault, mmu.page_fault, and fast_page_fault().
-- 
2.31.1


  parent reply	other threads:[~2021-06-25 15:32 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-25 15:32 [PATCH v2 0/9] KVM: X86: Some light optimizations on rmap logic Peter Xu
2021-06-25 15:32 ` [PATCH v2 1/9] KVM: X86: Add per-vm stat for max rmap list size Peter Xu
2021-06-25 15:32 ` [PATCH v2 2/9] KVM: Introduce kvm_get_kvm_safe() Peter Xu
2021-07-26 13:42   ` Paolo Bonzini
2021-06-25 15:32 ` [PATCH v2 3/9] KVM: Allow to have arch-specific per-vm debugfs files Peter Xu
2021-06-25 15:32 ` Peter Xu [this message]
2021-06-25 15:32 ` [PATCH v2 5/9] KVM: X86: Introduce kvm_mmu_slot_lpages() helpers Peter Xu
2021-06-25 15:32 ` [PATCH v2 6/9] KVM: X86: Introduce mmu_rmaps_stat per-vm debugfs file Peter Xu
2021-06-25 15:34 ` [PATCH v2 7/9] KVM: X86: MMU: Tune PTE_LIST_EXT to be bigger Peter Xu
2021-07-28 21:01   ` Sean Christopherson
2021-06-25 15:34 ` [PATCH v2 8/9] KVM: X86: Optimize pte_list_desc with per-array counter Peter Xu
2021-07-28 21:04   ` Sean Christopherson
2021-07-28 21:51     ` Peter Xu
2021-07-29  9:33       ` Paolo Bonzini
2021-07-29 15:53         ` Peter Xu
2021-07-30 15:45     ` Peter Xu
2021-06-25 15:34 ` [PATCH v2 9/9] KVM: X86: Optimize zapping rmap Peter Xu
2021-07-28 21:39   ` Sean Christopherson
2021-07-28 22:01     ` Peter Xu
2021-07-28 22:31       ` Sean Christopherson
2021-07-29  9:35         ` Paolo Bonzini
2021-07-26 13:05 ` [PATCH v2 0/9] KVM: X86: Some light optimizations on rmap logic Paolo Bonzini

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=20210625153214.43106-5-peterx@redhat.com \
    --to=peterx@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mlevitsk@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=seanjc@google.com \
    --cc=vkuznets@redhat.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).