diff mbox series

selftests/kvm: Allow specify physical cpu list in demand paging test

Message ID 20230503233812.2743269-1-peterx@redhat.com
State New
Headers
Series selftests/kvm: Allow specify physical cpu list in demand paging test |

Commit Message

Peter Xu May 3, 2023, 11:38 p.m. UTC 
  Mimic dirty log test to allow specify physical cpu pinning for vcpu threads.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 tools/testing/selftests/kvm/demand_paging_test.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

Comments

Sean Christopherson May 31, 2023, 10:15 p.m. UTC | #1 
On Wed, May 03, 2023, Peter Xu wrote:
> Mimic dirty log test to allow specify physical cpu pinning for vcpu threads.
> 
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  tools/testing/selftests/kvm/demand_paging_test.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> index bdb8e0748154..d709b65fda2f 100644
> --- a/tools/testing/selftests/kvm/demand_paging_test.c
> +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> @@ -220,12 +220,13 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  static void help(char *name)
>  {
>  	puts("");
> -	printf("usage: %s [-h] [-m vm_mode] [-u uffd_mode] [-a]\n"
> +	printf("usage: %s [-h] [-m vm_mode] [-u uffd_mode] [-a] [-c cpu_list]\n"
>  		   "          [-d uffd_delay_usec] [-r readers_per_uffd] [-b memory]\n"
>  		   "          [-s type] [-v vcpus] [-o]\n", name);
>  	guest_modes_help();
>  	printf(" -u: use userfaultfd to handle vCPU page faults. Mode is a\n"
>  	       "     UFFD registration mode: 'MISSING' or 'MINOR'.\n");
> +	printf(" -c: physical cores to pin vcpu threads (e.g. 1,2,3,...)\n");

This help really should be provided by kvm_util.c, e.g. this doesn't capture the
"must pin all vCPUs" behavior, nor does it capture the "pin the main thread"
behavior.

Something like this?

void kvm_get_vcpu_pinning_help(char *buffer, size_t size,
			       const char *optchar, const char *testname)
{
	snprintf(buffer, size,
		 " -%c: Pin tasks to physical CPUs.  Takes a list of comma separated\n"
		 "     values (target pCPU), one for each vCPU, plus an optional\n"
		 "     entry for the main application task (specified via entry\n"
		 "     <nr_vcpus + 1>).  If used, entries must be provided for all\n"
		 "     vCPUs, i.e. pinning vCPUs is all or nothing.\n\n"
		 "     E.g. to create 3 vCPUs, pin vCPU0=>pCPU22, vCPU1=>pCPU23,\n"
		 "     vCPU2=>pCPU24, and pin the application task to pCPU50:\n\n"
		 "         ./%s -v 3 -c 22,23,24,50\n\n"
		 "     To leave the application task unpinned, drop the final entry:\n\n"
		 "         ./%s -v 3 -c 22,23,24\n\n"
		 "     (default: no pinning)\n", optchar, testname);
}
Peter Xu June 1, 2023, 6:37 p.m. UTC | #2 
On Wed, May 31, 2023 at 03:15:52PM -0700, Sean Christopherson wrote:
> On Wed, May 03, 2023, Peter Xu wrote:
> > Mimic dirty log test to allow specify physical cpu pinning for vcpu threads.
> > 
> > Signed-off-by: Peter Xu <peterx@redhat.com>
> > ---
> >  tools/testing/selftests/kvm/demand_paging_test.c | 15 +++++++++++++--
> >  1 file changed, 13 insertions(+), 2 deletions(-)
> > 
> > diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> > index bdb8e0748154..d709b65fda2f 100644
> > --- a/tools/testing/selftests/kvm/demand_paging_test.c
> > +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> > @@ -220,12 +220,13 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> >  static void help(char *name)
> >  {
> >  	puts("");
> > -	printf("usage: %s [-h] [-m vm_mode] [-u uffd_mode] [-a]\n"
> > +	printf("usage: %s [-h] [-m vm_mode] [-u uffd_mode] [-a] [-c cpu_list]\n"
> >  		   "          [-d uffd_delay_usec] [-r readers_per_uffd] [-b memory]\n"
> >  		   "          [-s type] [-v vcpus] [-o]\n", name);
> >  	guest_modes_help();
> >  	printf(" -u: use userfaultfd to handle vCPU page faults. Mode is a\n"
> >  	       "     UFFD registration mode: 'MISSING' or 'MINOR'.\n");
> > +	printf(" -c: physical cores to pin vcpu threads (e.g. 1,2,3,...)\n");
> 
> This help really should be provided by kvm_util.c, e.g. this doesn't capture the
> "must pin all vCPUs" behavior, nor does it capture the "pin the main thread"
> behavior.
> 
> Something like this?
> 
> void kvm_get_vcpu_pinning_help(char *buffer, size_t size,
> 			       const char *optchar, const char *testname)
> {
> 	snprintf(buffer, size,
> 		 " -%c: Pin tasks to physical CPUs.  Takes a list of comma separated\n"
> 		 "     values (target pCPU), one for each vCPU, plus an optional\n"
> 		 "     entry for the main application task (specified via entry\n"
> 		 "     <nr_vcpus + 1>).  If used, entries must be provided for all\n"
> 		 "     vCPUs, i.e. pinning vCPUs is all or nothing.\n\n"
> 		 "     E.g. to create 3 vCPUs, pin vCPU0=>pCPU22, vCPU1=>pCPU23,\n"
> 		 "     vCPU2=>pCPU24, and pin the application task to pCPU50:\n\n"
> 		 "         ./%s -v 3 -c 22,23,24,50\n\n"
> 		 "     To leave the application task unpinned, drop the final entry:\n\n"
> 		 "         ./%s -v 3 -c 22,23,24\n\n"
> 		 "     (default: no pinning)\n", optchar, testname);
> }

Sure, I'll respin.  For the long term maybe we'll want to switch to libnuma
to take things easily like "1,2,5-10", but I'll leave that for later.
diff mbox series

Patch

diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index bdb8e0748154..d709b65fda2f 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -220,12 +220,13 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 static void help(char *name)
 {
 	puts("");
-	printf("usage: %s [-h] [-m vm_mode] [-u uffd_mode] [-a]\n"
+	printf("usage: %s [-h] [-m vm_mode] [-u uffd_mode] [-a] [-c cpu_list]\n"
 		   "          [-d uffd_delay_usec] [-r readers_per_uffd] [-b memory]\n"
 		   "          [-s type] [-v vcpus] [-o]\n", name);
 	guest_modes_help();
 	printf(" -u: use userfaultfd to handle vCPU page faults. Mode is a\n"
 	       "     UFFD registration mode: 'MISSING' or 'MINOR'.\n");
+	printf(" -c: physical cores to pin vcpu threads (e.g. 1,2,3,...)\n");
 	printf(" -a: Use a single userfaultfd for all of guest memory, instead of\n"
 		   "     creating one for each region paged by a unique vCPU\n"
 		   "     Set implicitly with -o, and no effect without -u.\n");
@@ -247,6 +248,7 @@  static void help(char *name)
 int main(int argc, char *argv[])
 {
 	int max_vcpus = kvm_check_cap(KVM_CAP_MAX_VCPUS);
+	const char *cpulist = NULL;
 	struct test_params p = {
 		.src_type = DEFAULT_VM_MEM_SRC,
 		.partition_vcpu_memory_access = true,
@@ -257,7 +259,7 @@  int main(int argc, char *argv[])
 
 	guest_modes_append_default();
 
-	while ((opt = getopt(argc, argv, "ahom:u:d:b:s:v:r:")) != -1) {
+	while ((opt = getopt(argc, argv, "ac:hom:u:d:b:s:v:r:")) != -1) {
 		switch (opt) {
 		case 'm':
 			guest_modes_cmdline(optarg);
@@ -272,6 +274,9 @@  int main(int argc, char *argv[])
 		case 'a':
 			p.single_uffd = true;
 			break;
+		case 'c':
+			cpulist = optarg;
+			break;
 		case 'd':
 			p.uffd_delay = strtoul(optarg, NULL, 0);
 			TEST_ASSERT(p.uffd_delay >= 0, "A negative UFFD delay is not supported.");
@@ -309,6 +314,12 @@  int main(int argc, char *argv[])
 		TEST_FAIL("userfaultfd MINOR mode requires shared memory; pick a different -s");
 	}
 
+	if (cpulist) {
+		kvm_parse_vcpu_pinning(cpulist, memstress_args.vcpu_to_pcpu,
+				       nr_vcpus);
+		memstress_args.pin_vcpus = true;
+	}
+
 	for_each_guest_mode(run_test, &p);
 
 	return 0;