All of lore.kernel.org
 help / color / mirror / Atom feed
From: Ben Gardon <bgardon@google.com>
To: kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>
Cc: linux-kernel@vger.kernel.org, Peter Xu <peterx@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	David Matlack <dmatlack@google.com>,
	Jim Mattson <jmattson@google.com>,
	David Dunn <daviddunn@google.com>,
	Jing Zhang <jingzhangos@google.com>,
	Junaid Shahid <junaids@google.com>,
	Ben Gardon <bgardon@google.com>
Subject: [PATCH v9 10/10] KVM: selftests: Cache binary stats metadata for duration of test
Date: Mon, 13 Jun 2022 21:25:23 +0000	[thread overview]
Message-ID: <20220613212523.3436117-11-bgardon@google.com> (raw)
In-Reply-To: <20220613212523.3436117-1-bgardon@google.com>

In order to improve performance across multiple reads of VM stats, cache
the stats metadata in the VM struct.

Signed-off-by: Ben Gardon <bgardon@google.com>
---
 .../selftests/kvm/include/kvm_util_base.h     |  5 +++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 32 ++++++++++---------
 2 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index 537b8a047d6e..daf201174d2a 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -84,6 +84,11 @@ struct kvm_vm {
 	vm_vaddr_t idt;
 	vm_vaddr_t handlers;
 	uint32_t dirty_ring_size;
+
+	/* Cache of information for binary stats interface */
+	int stats_fd;
+	struct kvm_stats_header stats_header;
+	struct kvm_stats_desc *stats_desc;
 };
 
 
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 0d97142a590e..787aeb0c61f3 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -551,6 +551,12 @@ void kvm_vm_free(struct kvm_vm *vmp)
 	if (vmp == NULL)
 		return;
 
+	/* Free cached stats metadata and close FD */
+	if (vmp->stats_fd) {
+		free(vmp->stats_desc);
+		close(vmp->stats_fd);
+	}
+
 	/* Free userspace_mem_regions. */
 	hash_for_each_safe(vmp->regions.slot_hash, ctr, node, region, slot_node)
 		__vm_mem_region_delete(vmp, region, false);
@@ -1942,32 +1948,28 @@ void read_stat_data(int stats_fd, struct kvm_stats_header *header,
 void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
 		   size_t max_elements)
 {
-	struct kvm_stats_desc *stats_desc;
-	struct kvm_stats_header header;
 	struct kvm_stats_desc *desc;
 	size_t size_desc;
-	int stats_fd;
 	int i;
 
-	stats_fd = vm_get_stats_fd(vm);
-
-	read_stats_header(stats_fd, &header);
-
-	stats_desc = read_stats_descriptors(stats_fd, &header);
+	if (!vm->stats_fd) {
+		vm->stats_fd = vm_get_stats_fd(vm);
+		read_stats_header(vm->stats_fd, &vm->stats_header);
+		vm->stats_desc = read_stats_descriptors(vm->stats_fd,
+							&vm->stats_header);
+	}
 
-	size_desc = get_stats_descriptor_size(&header);
+	size_desc = get_stats_descriptor_size(&vm->stats_header);
 
-	for (i = 0; i < header.num_desc; ++i) {
-		desc = (void *)stats_desc + (i * size_desc);
+	for (i = 0; i < vm->stats_header.num_desc; ++i) {
+		desc = (void *)vm->stats_desc + (i * size_desc);
 
 		if (strcmp(desc->name, stat_name))
 			continue;
 
-		read_stat_data(stats_fd, &header, desc, data, max_elements);
+		read_stat_data(vm->stats_fd, &vm->stats_header, desc,
+			       data, max_elements);
 
 		break;
 	}
-
-	free(stats_desc);
-	close(stats_fd);
 }
-- 
2.36.1.476.g0c4daa206d-goog


      parent reply	other threads:[~2022-06-13 21:30 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-06-13 21:25 [PATCH v9 00/10] KVM: x86: Add a cap to disable NX hugepages on a VM Ben Gardon
2022-06-13 21:25 ` [PATCH v9 01/10] KVM: selftests: Remove dynamic memory allocation for stats header Ben Gardon
2022-06-13 21:25 ` [PATCH v9 02/10] KVM: selftests: Read binary stats header in lib Ben Gardon
2022-06-13 21:25 ` [PATCH v9 03/10] KVM: selftests: Read binary stats desc " Ben Gardon
2022-06-13 21:25 ` [PATCH v9 04/10] KVM: selftests: Clean up coding style in binary stats test Ben Gardon
2022-06-13 21:25 ` [PATCH v9 05/10] KVM: selftests: Read binary stat data in lib Ben Gardon
2022-06-13 21:25 ` [PATCH v9 06/10] KVM: selftests: Add NX huge pages test Ben Gardon
2022-06-13 21:25 ` [PATCH v9 07/10] KVM: x86: Fix errant brace in KVM capability handling Ben Gardon
2022-06-13 21:25 ` [PATCH v9 08/10] KVM: x86/MMU: Allow NX huge pages to be disabled on a per-vm basis Ben Gardon
2022-06-13 21:25 ` [PATCH v9 09/10] KVM: selftests: Test disabling NX hugepages on a VM Ben Gardon
2022-06-13 21:25 ` Ben Gardon [this message]

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=20220613212523.3436117-11-bgardon@google.com \
    --to=bgardon@google.com \
    --cc=daviddunn@google.com \
    --cc=dmatlack@google.com \
    --cc=jingzhangos@google.com \
    --cc=jmattson@google.com \
    --cc=junaids@google.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=peterx@redhat.com \
    --cc=seanjc@google.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.