[v1] KVM: selftests: name the threads

Message ID 20221017162448.257173-1-wei.w.wang@intel.com
State New
Headers
Series [v1] KVM: selftests: name the threads |

Commit Message

Wang, Wei W Oct. 17, 2022, 4:24 p.m. UTC
  Name the threads to facilitate debugging, performance tuning,
runtime pining etc. pthread_create_with_name is used to create
general threads with user specified name, and kvm_vcpu_thread_create
is used to create vcpu threads with name in "vcpu##id" format.

An example is shown below reported from "top". With naming the
vcpu threads, the per-vcpu info becomes more noticeable.

PID  USER PR  NI VIRT    RES  SHR  S  %CPU  %MEM TIME+   COMMAND
4464 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.97 dirty_log_perf_
4467 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.93 vcpu0
4469 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.93 vcpu2
4470 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.94 vcpu3
4468 root 20  0  4248684 4.0g 1628 R  99.7  26.2 0:50.93 vcpu1

pthread.h is included in kvm_util.h, so remove it from the files
that have already included kvm_util.h.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
---
 .../selftests/kvm/aarch64/arch_timer.c        | 16 ++-----
 .../selftests/kvm/access_tracking_perf_test.c |  1 -
 .../selftests/kvm/demand_paging_test.c        |  5 +-
 .../selftests/kvm/dirty_log_perf_test.c       |  1 -
 tools/testing/selftests/kvm/dirty_log_test.c  |  2 +-
 .../selftests/kvm/hardware_disable_test.c     | 17 ++-----
 .../testing/selftests/kvm/include/kvm_util.h  |  8 ++++
 .../selftests/kvm/include/perf_test_util.h    |  2 -
 .../selftests/kvm/kvm_page_table_test.c       |  5 +-
 tools/testing/selftests/kvm/lib/kvm_util.c    | 47 +++++++++++++++++++
 .../selftests/kvm/lib/perf_test_util.c        |  3 +-
 .../selftests/kvm/max_guest_memory_test.c     |  4 +-
 .../kvm/memslot_modification_stress_test.c    |  1 -
 .../testing/selftests/kvm/memslot_perf_test.c |  3 +-
 tools/testing/selftests/kvm/rseq_test.c       |  5 +-
 .../selftests/kvm/set_memory_region_test.c    |  3 +-
 tools/testing/selftests/kvm/steal_time.c      |  4 +-
 .../selftests/kvm/x86_64/mmio_warning_test.c  |  3 +-
 .../selftests/kvm/x86_64/sev_migrate_tests.c  |  1 -
 .../selftests/kvm/x86_64/tsc_scaling_sync.c   |  4 +-
 .../kvm/x86_64/ucna_injection_test.c          |  1 -
 .../selftests/kvm/x86_64/xapic_ipi_test.c     | 10 ++--
 22 files changed, 85 insertions(+), 61 deletions(-)
  

Comments

David Matlack Oct. 19, 2022, 5:29 p.m. UTC | #1
On Tue, Oct 18, 2022 at 12:24:48AM +0800, Wei Wang wrote:
> Name the threads to facilitate debugging, performance tuning,
> runtime pining etc. pthread_create_with_name is used to create
> general threads with user specified name, and kvm_vcpu_thread_create
> is used to create vcpu threads with name in "vcpu##id" format.
> 
> An example is shown below reported from "top". With naming the
> vcpu threads, the per-vcpu info becomes more noticeable.
> 
> PID  USER PR  NI VIRT    RES  SHR  S  %CPU  %MEM TIME+   COMMAND
> 4464 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.97 dirty_log_perf_
> 4467 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.93 vcpu0
> 4469 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.93 vcpu2
> 4470 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.94 vcpu3
> 4468 root 20  0  4248684 4.0g 1628 R  99.7  26.2 0:50.93 vcpu1
> 
> pthread.h is included in kvm_util.h, so remove it from the files
> that have already included kvm_util.h.
> 
> Signed-off-by: Wei Wang <wei.w.wang@intel.com>
> ---
>  .../selftests/kvm/aarch64/arch_timer.c        | 16 ++-----
>  .../selftests/kvm/access_tracking_perf_test.c |  1 -
>  .../selftests/kvm/demand_paging_test.c        |  5 +-
>  .../selftests/kvm/dirty_log_perf_test.c       |  1 -
>  tools/testing/selftests/kvm/dirty_log_test.c  |  2 +-
>  .../selftests/kvm/hardware_disable_test.c     | 17 ++-----
>  .../testing/selftests/kvm/include/kvm_util.h  |  8 ++++
>  .../selftests/kvm/include/perf_test_util.h    |  2 -
>  .../selftests/kvm/kvm_page_table_test.c       |  5 +-
>  tools/testing/selftests/kvm/lib/kvm_util.c    | 47 +++++++++++++++++++
>  .../selftests/kvm/lib/perf_test_util.c        |  3 +-
>  .../selftests/kvm/max_guest_memory_test.c     |  4 +-
>  .../kvm/memslot_modification_stress_test.c    |  1 -
>  .../testing/selftests/kvm/memslot_perf_test.c |  3 +-
>  tools/testing/selftests/kvm/rseq_test.c       |  5 +-
>  .../selftests/kvm/set_memory_region_test.c    |  3 +-
>  tools/testing/selftests/kvm/steal_time.c      |  4 +-
>  .../selftests/kvm/x86_64/mmio_warning_test.c  |  3 +-
>  .../selftests/kvm/x86_64/sev_migrate_tests.c  |  1 -
>  .../selftests/kvm/x86_64/tsc_scaling_sync.c   |  4 +-
>  .../kvm/x86_64/ucna_injection_test.c          |  1 -
>  .../selftests/kvm/x86_64/xapic_ipi_test.c     | 10 ++--
>  22 files changed, 85 insertions(+), 61 deletions(-)
> 
> diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
> index 574eb73f0e90..14f56327ca28 100644
> --- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
> +++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
> @@ -23,7 +23,6 @@
>  #define _GNU_SOURCE
>  
>  #include <stdlib.h>
> -#include <pthread.h>
>  #include <linux/kvm.h>
>  #include <linux/sizes.h>
>  #include <linux/bitmap.h>
> @@ -314,28 +313,23 @@ static void test_run(struct kvm_vm *vm)
>  {
>  	pthread_t pt_vcpu_migration;
>  	unsigned int i;
> -	int ret;
>  
>  	pthread_mutex_init(&vcpu_done_map_lock, NULL);
>  	vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
>  	TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap\n");
>  
> -	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
> -		ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
> -				     (void *)(unsigned long)i);
> -		TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread\n", i);
> -	}
> +	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++)
> +		kvm_create_vcpu_thread(&pt_vcpu_run[i], NULL,
> +				test_vcpu_run, (void *)(unsigned long)i, i);
>  
>  	/* Spawn a thread to control the vCPU migrations */
>  	if (test_args.migration_freq_ms) {
>  		srand(time(NULL));
>  
> -		ret = pthread_create(&pt_vcpu_migration, NULL,
> -					test_vcpu_migration, NULL);
> -		TEST_ASSERT(!ret, "Failed to create the migration pthread\n");
> +		pthread_create_with_name(&pt_vcpu_migration, NULL,
> +				test_vcpu_migration, NULL, "control-thread");
>  	}
>  
> -
>  	for (i = 0; i < test_args.nr_vcpus; i++)
>  		pthread_join(pt_vcpu_run[i], NULL);
>  
> diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c
> index 76c583a07ea2..b61ecc907d61 100644
> --- a/tools/testing/selftests/kvm/access_tracking_perf_test.c
> +++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c
> @@ -37,7 +37,6 @@
>   */
>  #include <inttypes.h>
>  #include <limits.h>
> -#include <pthread.h>
>  #include <sys/mman.h>
>  #include <sys/types.h>
>  #include <sys/stat.h>
> diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> index 779ae54f89c4..f75d531008e8 100644
> --- a/tools/testing/selftests/kvm/demand_paging_test.c
> +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> @@ -14,7 +14,6 @@
>  #include <stdlib.h>
>  #include <time.h>
>  #include <poll.h>
> -#include <pthread.h>
>  #include <linux/userfaultfd.h>
>  #include <sys/syscall.h>
>  
> @@ -260,8 +259,8 @@ static void setup_demand_paging(struct kvm_vm *vm,
>  	uffd_args->uffd = uffd;
>  	uffd_args->pipefd = pipefd;
>  	uffd_args->delay = uffd_delay;
> -	pthread_create(uffd_handler_thread, NULL, uffd_handler_thread_fn,
> -		       uffd_args);
> +	pthread_create_with_name(uffd_handler_thread, NULL,
> +		uffd_handler_thread_fn, uffd_args, "uffd-handler-thread");
>  
>  	PER_VCPU_DEBUG("Created uffd thread for HVA range [%p, %p)\n",
>  		       hva, hva + len);
> diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> index f99e39a672d3..5cf9080b3864 100644
> --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
> +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> @@ -11,7 +11,6 @@
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <time.h>
> -#include <pthread.h>
>  #include <linux/bitmap.h>
>  
>  #include "kvm_util.h"
> diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
> index b5234d6efbe1..c7a30b4dd33a 100644
> --- a/tools/testing/selftests/kvm/dirty_log_test.c
> +++ b/tools/testing/selftests/kvm/dirty_log_test.c
> @@ -772,7 +772,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  	host_clear_count = 0;
>  	host_track_next_count = 0;
>  
> -	pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);
> +	kvm_create_vcpu_thread(&vcpu_thread, NULL, vcpu_worker, vcpu, 0);
>  
>  	while (iteration < p->iterations) {
>  		/* Give the vcpu thread some time to dirty some pages */
> diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c
> index f5d59b9934f1..c22b8445a809 100644
> --- a/tools/testing/selftests/kvm/hardware_disable_test.c
> +++ b/tools/testing/selftests/kvm/hardware_disable_test.c
> @@ -8,7 +8,6 @@
>  #define _GNU_SOURCE
>  
>  #include <fcntl.h>
> -#include <pthread.h>
>  #include <semaphore.h>
>  #include <stdint.h>
>  #include <stdlib.h>
> @@ -59,15 +58,6 @@ static void *sleeping_thread(void *arg)
>  	pthread_exit(NULL);
>  }
>  
> -static inline void check_create_thread(pthread_t *thread, pthread_attr_t *attr,
> -				       void *(*f)(void *), void *arg)
> -{
> -	int r;
> -
> -	r = pthread_create(thread, attr, f, arg);
> -	TEST_ASSERT(r == 0, "%s: failed to create thread", __func__);
> -}
> -
>  static inline void check_set_affinity(pthread_t thread, cpu_set_t *cpu_set)
>  {
>  	int r;
> @@ -104,12 +94,13 @@ static void run_test(uint32_t run)
>  	for (i = 0; i < VCPU_NUM; ++i) {
>  		vcpu = vm_vcpu_add(vm, i, guest_code);
>  
> -		check_create_thread(&threads[i], NULL, run_vcpu, vcpu);
> +		kvm_create_vcpu_thread(&threads[i], NULL, run_vcpu, vcpu, i);
>  		check_set_affinity(threads[i], &cpu_set);
>  
>  		for (j = 0; j < SLEEPING_THREAD_NUM; ++j) {
> -			check_create_thread(&throw_away, NULL, sleeping_thread,
> -					    (void *)NULL);
> +			pthread_create_with_name(&throw_away, NULL,
> +						 sleeping_thread, (void *)NULL,
> +						 "sleeping-thread");
>  			check_set_affinity(throw_away, &cpu_set);
>  		}
>  	}
> diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> index c9286811a4cb..b7f0295d928e 100644
> --- a/tools/testing/selftests/kvm/include/kvm_util.h
> +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> @@ -7,7 +7,15 @@
>  #ifndef SELFTEST_KVM_UTIL_H
>  #define SELFTEST_KVM_UTIL_H
>  
> +#include <pthread.h>
> +
>  #include "kvm_util_base.h"
>  #include "ucall_common.h"
>  
> +void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
> +			void *(*start_routine)(void *), void *arg, char *name);
> +
> +void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t *attr,
> +		void *(*start_routine)(void *), void *arg, int vcpu_id);
> +
>  #endif /* SELFTEST_KVM_UTIL_H */
> diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h
> index eaa88df0555a..cb6971c8740f 100644
> --- a/tools/testing/selftests/kvm/include/perf_test_util.h
> +++ b/tools/testing/selftests/kvm/include/perf_test_util.h
> @@ -8,8 +8,6 @@
>  #ifndef SELFTEST_KVM_PERF_TEST_UTIL_H
>  #define SELFTEST_KVM_PERF_TEST_UTIL_H
>  
> -#include <pthread.h>
> -
>  #include "kvm_util.h"
>  
>  /* Default guest test virtual memory offset */
> diff --git a/tools/testing/selftests/kvm/kvm_page_table_test.c b/tools/testing/selftests/kvm/kvm_page_table_test.c
> index f42c6ac6d71d..1e41dca7f67d 100644
> --- a/tools/testing/selftests/kvm/kvm_page_table_test.c
> +++ b/tools/testing/selftests/kvm/kvm_page_table_test.c
> @@ -14,7 +14,6 @@
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <time.h>
> -#include <pthread.h>
>  #include <semaphore.h>
>  
>  #include "test_util.h"
> @@ -359,8 +358,8 @@ static void run_test(enum vm_guest_mode mode, void *arg)
>  	*current_stage = KVM_BEFORE_MAPPINGS;
>  
>  	for (i = 0; i < nr_vcpus; i++)
> -		pthread_create(&vcpu_threads[i], NULL, vcpu_worker,
> -			       test_args.vcpus[i]);
> +		kvm_create_vcpu_thread(&vcpu_threads[i], NULL,
> +				       vcpu_worker, test_args.vcpus[i], i);
>  
>  	vcpus_complete_new_stage(*current_stage);
>  	pr_info("Started all vCPUs successfully\n");
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index f1cb1627161f..c252c912f1ba 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -2021,3 +2021,50 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
>  		break;
>  	}
>  }
> +
> +/*
> + * Create a named thread
> + *
> + * Input Args:

thread is missing here

> + *   attr - the attributes for the new thread
> + *   start_routine - the routine to run in the thread context
> + *   arg - the argument passed to start_routine
> + *   name - the name of the thread
> + *
> + * Output Args:
> + *   thread - the thread to be created
> + *
> + * Create a thread with user specified name.
> + */
> +void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
> +			void *(*start_routine)(void *), void *arg, char *name)
> +{
> +	int r;
> +
> +	r = pthread_create(thread, attr, start_routine, arg);
> +	TEST_ASSERT(!r, "thread(%s) creation failed, r = %d", name, r);
> +	pthread_setname_np(*thread, name);
> +}
> +
> +/*
> + * Create a vcpu thread
> + *
> + * Input Args:

thread is missing here

> + *   attr - the attributes for the new thread
> + *   start_routine - the routine to run in the thread context
> + *   arg - the argument passed to start_routine
> + *   vcpu_id - the id of the vcpu
> + *
> + * Output Args:
> + *   thread - the thread to be created
> + *
> + * Create a vcpu thread with the name in "vcpu##id" format.
> + */
> +void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t *attr,

If I'm reading the patch correctly, attr is always NULL for vCPU
threads, so just drop it until we need it?

> +			void *(*start_routine)(void *), void *arg, int vcpu_id)

I think it would be helpful to tie the vcpu_id to something real, rather
than leaving it up to the caller. How about passing in the struct
kvm_vcpu here and using vcpu->id in the thread name?

Another cleanup we could do on top of this series would be to stash the
vCPU pthread_t into struct kvm_vcpu, which would eliminate another
parameter here and make this API super clean:

void vcpu_create_thread(struct kvm_vcpu *vcpu, void *(*fn)(void *), void *arg)
{
	...
}

> +{
> +	char vcpu_name[6];
> +
> +	sprintf(vcpu_name, "%s%d", "vcpu", vcpu_id);

There's no need to dynamically insert "vcpu". Also, could we include a
dash to make the name slightly easier to parse? Putting it together...

	char vcpu_name[16];

	sprintf(vcpu_name, "vcpu-%d", vcpu_id);

> +	pthread_create_with_name(thread, attr, start_routine, arg, vcpu_name);
> +}
> diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c
> index 9618b37c66f7..4e57181daffc 100644
> --- a/tools/testing/selftests/kvm/lib/perf_test_util.c
> +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c
> @@ -274,7 +274,8 @@ void perf_test_start_vcpu_threads(int nr_vcpus,
>  		vcpu->vcpu_idx = i;
>  		WRITE_ONCE(vcpu->running, false);
>  
> -		pthread_create(&vcpu->thread, NULL, vcpu_thread_main, vcpu);
> +		kvm_create_vcpu_thread(&vcpu->thread, NULL,
> +				       vcpu_thread_main, vcpu, i);
>  	}
>  
>  	for (i = 0; i < nr_vcpus; i++) {
> diff --git a/tools/testing/selftests/kvm/max_guest_memory_test.c b/tools/testing/selftests/kvm/max_guest_memory_test.c
> index 9a6e4f3ad6b5..04524694e2b6 100644
> --- a/tools/testing/selftests/kvm/max_guest_memory_test.c
> +++ b/tools/testing/selftests/kvm/max_guest_memory_test.c
> @@ -3,7 +3,6 @@
>  
>  #include <stdio.h>
>  #include <stdlib.h>
> -#include <pthread.h>
>  #include <semaphore.h>
>  #include <sys/types.h>
>  #include <signal.h>
> @@ -110,7 +109,8 @@ static pthread_t *spawn_workers(struct kvm_vm *vm, struct kvm_vcpu **vcpus,
>  		info[i].vcpu = vcpus[i];
>  		info[i].start_gpa = gpa;
>  		info[i].end_gpa = gpa + nr_bytes;
> -		pthread_create(&threads[i], NULL, vcpu_worker, &info[i]);
> +		kvm_create_vcpu_thread(&threads[i], NULL,
> +				       vcpu_worker, &info[i], i);
>  	}
>  	return threads;
>  }
> diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
> index 6ee7e1dde404..769300181597 100644
> --- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c
> +++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
> @@ -16,7 +16,6 @@
>  #include <asm/unistd.h>
>  #include <time.h>
>  #include <poll.h>
> -#include <pthread.h>
>  #include <linux/bitmap.h>
>  #include <linux/bitops.h>
>  #include <linux/userfaultfd.h>
> diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c
> index 44995446d942..041a07acba3d 100644
> --- a/tools/testing/selftests/kvm/memslot_perf_test.c
> +++ b/tools/testing/selftests/kvm/memslot_perf_test.c
> @@ -6,7 +6,6 @@
>   *
>   * Basic guest setup / host vCPU thread code lifted from set_memory_region_test.
>   */
> -#include <pthread.h>
>  #include <sched.h>
>  #include <semaphore.h>
>  #include <stdatomic.h>
> @@ -332,7 +331,7 @@ static void launch_vm(struct vm_data *data)
>  {
>  	pr_info_v("Launching the test VM\n");
>  
> -	pthread_create(&data->vcpu_thread, NULL, vcpu_worker, data);
> +	kvm_create_vcpu_thread(&data->vcpu_thread, NULL, vcpu_worker, data, 0);
>  
>  	/* Ensure the guest thread is spun up. */
>  	wait_for_vcpu();
> diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
> index 6f88da7e60be..11e0b1b7abb1 100644
> --- a/tools/testing/selftests/kvm/rseq_test.c
> +++ b/tools/testing/selftests/kvm/rseq_test.c
> @@ -2,7 +2,6 @@
>  #define _GNU_SOURCE /* for program_invocation_short_name */
>  #include <errno.h>
>  #include <fcntl.h>
> -#include <pthread.h>
>  #include <sched.h>
>  #include <stdio.h>
>  #include <stdlib.h>
> @@ -226,8 +225,8 @@ int main(int argc, char *argv[])
>  	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
>  	ucall_init(vm, NULL);
>  
> -	pthread_create(&migration_thread, NULL, migration_worker,
> -		       (void *)(unsigned long)syscall(SYS_gettid));
> +	pthread_create_with_name(&migration_thread, NULL, migration_worker,
> +	       (void *)(unsigned long)syscall(SYS_gettid), "migration-thread");
>  
>  	for (i = 0; !done; i++) {
>  		vcpu_run(vcpu);
> diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
> index 0d55f508d595..4c9ab5595a22 100644
> --- a/tools/testing/selftests/kvm/set_memory_region_test.c
> +++ b/tools/testing/selftests/kvm/set_memory_region_test.c
> @@ -1,7 +1,6 @@
>  // SPDX-License-Identifier: GPL-2.0
>  #define _GNU_SOURCE /* for program_invocation_short_name */
>  #include <fcntl.h>
> -#include <pthread.h>
>  #include <sched.h>
>  #include <semaphore.h>
>  #include <signal.h>
> @@ -134,7 +133,7 @@ static struct kvm_vm *spawn_vm(struct kvm_vcpu **vcpu, pthread_t *vcpu_thread,
>  	hva = addr_gpa2hva(vm, MEM_REGION_GPA);
>  	memset(hva, 0, 2 * 4096);
>  
> -	pthread_create(vcpu_thread, NULL, vcpu_worker, *vcpu);
> +	kvm_create_vcpu_thread(vcpu_thread, NULL, vcpu_worker, *vcpu, 0);
>  
>  	/* Ensure the guest thread is spun up. */
>  	wait_for_vcpu();
> diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
> index db8967f1a17b..be93a333ce04 100644
> --- a/tools/testing/selftests/kvm/steal_time.c
> +++ b/tools/testing/selftests/kvm/steal_time.c
> @@ -8,7 +8,6 @@
>  #include <stdio.h>
>  #include <time.h>
>  #include <sched.h>
> -#include <pthread.h>
>  #include <linux/kernel.h>
>  #include <asm/kvm.h>
>  #include <asm/kvm_para.h>
> @@ -290,7 +289,8 @@ int main(int ac, char **av)
>  
>  		/* Steal time from the VCPU. The steal time thread has the same CPU affinity as the VCPUs. */
>  		run_delay = get_run_delay();
> -		pthread_create(&thread, &attr, do_steal_time, NULL);
> +		pthread_create_with_name(&thread, &attr, do_steal_time,
> +					 NULL, "steal-time-thread");
>  		do
>  			sched_yield();
>  		while (get_run_delay() - run_delay < MIN_RUN_DELAY_NS);
> diff --git a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
> index fb02581953a3..abbd5a4f2828 100644
> --- a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
> @@ -16,7 +16,6 @@
>  #include <kvm_util.h>
>  #include <linux/kvm.h>
>  #include <processor.h>
> -#include <pthread.h>
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <string.h>
> @@ -69,7 +68,7 @@ void test(void)
>  	tc.run = run;
>  	srand(getpid());
>  	for (i = 0; i < NTHREAD; i++) {
> -		pthread_create(&th[i], NULL, thr, (void *)(uintptr_t)&tc);
> +		kvm_create_vcpu_thread(&th[i], NULL, thr, (void *)(uintptr_t)&tc, i);
>  		usleep(rand() % 10000);
>  	}
>  	for (i = 0; i < NTHREAD; i++)
> diff --git a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> index c7ef97561038..b00ba08a19eb 100644
> --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> @@ -5,7 +5,6 @@
>  #include <sys/ioctl.h>
>  #include <stdlib.h>
>  #include <errno.h>
> -#include <pthread.h>
>  
>  #include "test_util.h"
>  #include "kvm_util.h"
> diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
> index 47139aab7408..a6511c399173 100644
> --- a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
> +++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
> @@ -15,7 +15,6 @@
>  #include <time.h>
>  #include <sched.h>
>  #include <signal.h>
> -#include <pthread.h>
>  
>  #define NR_TEST_VCPUS 20
>  
> @@ -102,7 +101,8 @@ int main(int argc, char *argv[])
>  	pthread_t cpu_threads[NR_TEST_VCPUS];
>  	unsigned long cpu;
>  	for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++)
> -		pthread_create(&cpu_threads[cpu], NULL, run_vcpu, (void *)cpu);
> +		kvm_create_vcpu_thread(&cpu_threads[cpu], NULL,
> +				       run_vcpu, (void *)cpu, cpu);
>  
>  	unsigned long failures = 0;
>  	for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) {
> diff --git a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
> index a897c7fd8abe..24a89a3a11db 100644
> --- a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
> @@ -19,7 +19,6 @@
>   */
>  
>  #define _GNU_SOURCE /* for program_invocation_short_name */
> -#include <pthread.h>
>  #include <inttypes.h>
>  #include <string.h>
>  #include <time.h>
> diff --git a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
> index 3d272d7f961e..8bdef8e0f2b0 100644
> --- a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
> +++ b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
> @@ -22,7 +22,6 @@
>  
>  #define _GNU_SOURCE /* for program_invocation_short_name */
>  #include <getopt.h>
> -#include <pthread.h>
>  #include <inttypes.h>
>  #include <string.h>
>  #include <time.h>
> @@ -393,7 +392,6 @@ void get_cmdline_args(int argc, char *argv[], int *run_secs,
>  
>  int main(int argc, char *argv[])
>  {
> -	int r;
>  	int wait_secs;
>  	const int max_halter_wait = 10;
>  	int run_secs = 0;
> @@ -436,9 +434,8 @@ int main(int argc, char *argv[])
>  	params[1].pipis_rcvd = pipis_rcvd;
>  
>  	/* Start halter vCPU thread and wait for it to execute first HLT. */
> -	r = pthread_create(&threads[0], NULL, vcpu_thread, &params[0]);
> -	TEST_ASSERT(r == 0,
> -		    "pthread_create halter failed errno=%d", errno);
> +	kvm_create_vcpu_thread(&threads[0], NULL,
> +			       vcpu_thread, &params[0], 0);
>  	fprintf(stderr, "Halter vCPU thread started\n");
>  
>  	wait_secs = 0;
> @@ -455,8 +452,7 @@ int main(int argc, char *argv[])
>  		"Halter vCPU thread reported its APIC ID: %u after %d seconds.\n",
>  		data->halter_apic_id, wait_secs);
>  
> -	r = pthread_create(&threads[1], NULL, vcpu_thread, &params[1]);
> -	TEST_ASSERT(r == 0, "pthread_create sender failed errno=%d", errno);
> +	kvm_create_vcpu_thread(&threads[1], NULL, vcpu_thread, &params[1], 1);
>  
>  	fprintf(stderr,
>  		"IPI sender vCPU thread started. Letting vCPUs run for %d seconds.\n",
> -- 
> 2.27.0
>
  
David Matlack Oct. 19, 2022, 5:31 p.m. UTC | #2
On Wed, Oct 19, 2022 at 10:29 AM David Matlack <dmatlack@google.com> wrote:
>
> On Tue, Oct 18, 2022 at 12:24:48AM +0800, Wei Wang wrote:
> > Name the threads to facilitate debugging, performance tuning,
> > runtime pining etc. pthread_create_with_name is used to create
> > general threads with user specified name, and kvm_vcpu_thread_create
> > is used to create vcpu threads with name in "vcpu##id" format.
> >
> > An example is shown below reported from "top". With naming the
> > vcpu threads, the per-vcpu info becomes more noticeable.
> >
> > PID  USER PR  NI VIRT    RES  SHR  S  %CPU  %MEM TIME+   COMMAND
> > 4464 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.97 dirty_log_perf_
> > 4467 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.93 vcpu0
> > 4469 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.93 vcpu2
> > 4470 root 20  0  4248684 4.0g 1628 R  99.9  26.2 0:50.94 vcpu3
> > 4468 root 20  0  4248684 4.0g 1628 R  99.7  26.2 0:50.93 vcpu1
> >
> > pthread.h is included in kvm_util.h, so remove it from the files
> > that have already included kvm_util.h.
> >
> > Signed-off-by: Wei Wang <wei.w.wang@intel.com>
> > ---
> >  .../selftests/kvm/aarch64/arch_timer.c        | 16 ++-----
> >  .../selftests/kvm/access_tracking_perf_test.c |  1 -
> >  .../selftests/kvm/demand_paging_test.c        |  5 +-
> >  .../selftests/kvm/dirty_log_perf_test.c       |  1 -
> >  tools/testing/selftests/kvm/dirty_log_test.c  |  2 +-
> >  .../selftests/kvm/hardware_disable_test.c     | 17 ++-----
> >  .../testing/selftests/kvm/include/kvm_util.h  |  8 ++++
> >  .../selftests/kvm/include/perf_test_util.h    |  2 -
> >  .../selftests/kvm/kvm_page_table_test.c       |  5 +-
> >  tools/testing/selftests/kvm/lib/kvm_util.c    | 47 +++++++++++++++++++
> >  .../selftests/kvm/lib/perf_test_util.c        |  3 +-
> >  .../selftests/kvm/max_guest_memory_test.c     |  4 +-
> >  .../kvm/memslot_modification_stress_test.c    |  1 -
> >  .../testing/selftests/kvm/memslot_perf_test.c |  3 +-
> >  tools/testing/selftests/kvm/rseq_test.c       |  5 +-
> >  .../selftests/kvm/set_memory_region_test.c    |  3 +-
> >  tools/testing/selftests/kvm/steal_time.c      |  4 +-
> >  .../selftests/kvm/x86_64/mmio_warning_test.c  |  3 +-
> >  .../selftests/kvm/x86_64/sev_migrate_tests.c  |  1 -
> >  .../selftests/kvm/x86_64/tsc_scaling_sync.c   |  4 +-
> >  .../kvm/x86_64/ucna_injection_test.c          |  1 -
> >  .../selftests/kvm/x86_64/xapic_ipi_test.c     | 10 ++--
> >  22 files changed, 85 insertions(+), 61 deletions(-)
> >
> > diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
> > index 574eb73f0e90..14f56327ca28 100644
> > --- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
> > +++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
> > @@ -23,7 +23,6 @@
> >  #define _GNU_SOURCE
> >
> >  #include <stdlib.h>
> > -#include <pthread.h>
> >  #include <linux/kvm.h>
> >  #include <linux/sizes.h>
> >  #include <linux/bitmap.h>
> > @@ -314,28 +313,23 @@ static void test_run(struct kvm_vm *vm)
> >  {
> >       pthread_t pt_vcpu_migration;
> >       unsigned int i;
> > -     int ret;
> >
> >       pthread_mutex_init(&vcpu_done_map_lock, NULL);
> >       vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
> >       TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap\n");
> >
> > -     for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
> > -             ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
> > -                                  (void *)(unsigned long)i);
> > -             TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread\n", i);
> > -     }
> > +     for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++)
> > +             kvm_create_vcpu_thread(&pt_vcpu_run[i], NULL,
> > +                             test_vcpu_run, (void *)(unsigned long)i, i);
> >
> >       /* Spawn a thread to control the vCPU migrations */
> >       if (test_args.migration_freq_ms) {
> >               srand(time(NULL));
> >
> > -             ret = pthread_create(&pt_vcpu_migration, NULL,
> > -                                     test_vcpu_migration, NULL);
> > -             TEST_ASSERT(!ret, "Failed to create the migration pthread\n");
> > +             pthread_create_with_name(&pt_vcpu_migration, NULL,
> > +                             test_vcpu_migration, NULL, "control-thread");
> >       }
> >
> > -
> >       for (i = 0; i < test_args.nr_vcpus; i++)
> >               pthread_join(pt_vcpu_run[i], NULL);
> >
> > diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c
> > index 76c583a07ea2..b61ecc907d61 100644
> > --- a/tools/testing/selftests/kvm/access_tracking_perf_test.c
> > +++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c
> > @@ -37,7 +37,6 @@
> >   */
> >  #include <inttypes.h>
> >  #include <limits.h>
> > -#include <pthread.h>
> >  #include <sys/mman.h>
> >  #include <sys/types.h>
> >  #include <sys/stat.h>
> > diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> > index 779ae54f89c4..f75d531008e8 100644
> > --- a/tools/testing/selftests/kvm/demand_paging_test.c
> > +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> > @@ -14,7 +14,6 @@
> >  #include <stdlib.h>
> >  #include <time.h>
> >  #include <poll.h>
> > -#include <pthread.h>
> >  #include <linux/userfaultfd.h>
> >  #include <sys/syscall.h>
> >
> > @@ -260,8 +259,8 @@ static void setup_demand_paging(struct kvm_vm *vm,
> >       uffd_args->uffd = uffd;
> >       uffd_args->pipefd = pipefd;
> >       uffd_args->delay = uffd_delay;
> > -     pthread_create(uffd_handler_thread, NULL, uffd_handler_thread_fn,
> > -                    uffd_args);
> > +     pthread_create_with_name(uffd_handler_thread, NULL,
> > +             uffd_handler_thread_fn, uffd_args, "uffd-handler-thread");
> >
> >       PER_VCPU_DEBUG("Created uffd thread for HVA range [%p, %p)\n",
> >                      hva, hva + len);
> > diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> > index f99e39a672d3..5cf9080b3864 100644
> > --- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
> > +++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
> > @@ -11,7 +11,6 @@
> >  #include <stdio.h>
> >  #include <stdlib.h>
> >  #include <time.h>
> > -#include <pthread.h>
> >  #include <linux/bitmap.h>
> >
> >  #include "kvm_util.h"
> > diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
> > index b5234d6efbe1..c7a30b4dd33a 100644
> > --- a/tools/testing/selftests/kvm/dirty_log_test.c
> > +++ b/tools/testing/selftests/kvm/dirty_log_test.c
> > @@ -772,7 +772,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> >       host_clear_count = 0;
> >       host_track_next_count = 0;
> >
> > -     pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);
> > +     kvm_create_vcpu_thread(&vcpu_thread, NULL, vcpu_worker, vcpu, 0);
> >
> >       while (iteration < p->iterations) {
> >               /* Give the vcpu thread some time to dirty some pages */
> > diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c
> > index f5d59b9934f1..c22b8445a809 100644
> > --- a/tools/testing/selftests/kvm/hardware_disable_test.c
> > +++ b/tools/testing/selftests/kvm/hardware_disable_test.c
> > @@ -8,7 +8,6 @@
> >  #define _GNU_SOURCE
> >
> >  #include <fcntl.h>
> > -#include <pthread.h>
> >  #include <semaphore.h>
> >  #include <stdint.h>
> >  #include <stdlib.h>
> > @@ -59,15 +58,6 @@ static void *sleeping_thread(void *arg)
> >       pthread_exit(NULL);
> >  }
> >
> > -static inline void check_create_thread(pthread_t *thread, pthread_attr_t *attr,
> > -                                    void *(*f)(void *), void *arg)
> > -{
> > -     int r;
> > -
> > -     r = pthread_create(thread, attr, f, arg);
> > -     TEST_ASSERT(r == 0, "%s: failed to create thread", __func__);
> > -}
> > -
> >  static inline void check_set_affinity(pthread_t thread, cpu_set_t *cpu_set)
> >  {
> >       int r;
> > @@ -104,12 +94,13 @@ static void run_test(uint32_t run)
> >       for (i = 0; i < VCPU_NUM; ++i) {
> >               vcpu = vm_vcpu_add(vm, i, guest_code);
> >
> > -             check_create_thread(&threads[i], NULL, run_vcpu, vcpu);
> > +             kvm_create_vcpu_thread(&threads[i], NULL, run_vcpu, vcpu, i);
> >               check_set_affinity(threads[i], &cpu_set);
> >
> >               for (j = 0; j < SLEEPING_THREAD_NUM; ++j) {
> > -                     check_create_thread(&throw_away, NULL, sleeping_thread,
> > -                                         (void *)NULL);
> > +                     pthread_create_with_name(&throw_away, NULL,
> > +                                              sleeping_thread, (void *)NULL,
> > +                                              "sleeping-thread");
> >                       check_set_affinity(throw_away, &cpu_set);
> >               }
> >       }
> > diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> > index c9286811a4cb..b7f0295d928e 100644
> > --- a/tools/testing/selftests/kvm/include/kvm_util.h
> > +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> > @@ -7,7 +7,15 @@
> >  #ifndef SELFTEST_KVM_UTIL_H
> >  #define SELFTEST_KVM_UTIL_H
> >
> > +#include <pthread.h>
> > +
> >  #include "kvm_util_base.h"
> >  #include "ucall_common.h"
> >
> > +void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
> > +                     void *(*start_routine)(void *), void *arg, char *name);
> > +
> > +void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t *attr,
> > +             void *(*start_routine)(void *), void *arg, int vcpu_id);
> > +
> >  #endif /* SELFTEST_KVM_UTIL_H */
> > diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h
> > index eaa88df0555a..cb6971c8740f 100644
> > --- a/tools/testing/selftests/kvm/include/perf_test_util.h
> > +++ b/tools/testing/selftests/kvm/include/perf_test_util.h
> > @@ -8,8 +8,6 @@
> >  #ifndef SELFTEST_KVM_PERF_TEST_UTIL_H
> >  #define SELFTEST_KVM_PERF_TEST_UTIL_H
> >
> > -#include <pthread.h>
> > -
> >  #include "kvm_util.h"
> >
> >  /* Default guest test virtual memory offset */
> > diff --git a/tools/testing/selftests/kvm/kvm_page_table_test.c b/tools/testing/selftests/kvm/kvm_page_table_test.c
> > index f42c6ac6d71d..1e41dca7f67d 100644
> > --- a/tools/testing/selftests/kvm/kvm_page_table_test.c
> > +++ b/tools/testing/selftests/kvm/kvm_page_table_test.c
> > @@ -14,7 +14,6 @@
> >  #include <stdio.h>
> >  #include <stdlib.h>
> >  #include <time.h>
> > -#include <pthread.h>
> >  #include <semaphore.h>
> >
> >  #include "test_util.h"
> > @@ -359,8 +358,8 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> >       *current_stage = KVM_BEFORE_MAPPINGS;
> >
> >       for (i = 0; i < nr_vcpus; i++)
> > -             pthread_create(&vcpu_threads[i], NULL, vcpu_worker,
> > -                            test_args.vcpus[i]);
> > +             kvm_create_vcpu_thread(&vcpu_threads[i], NULL,
> > +                                    vcpu_worker, test_args.vcpus[i], i);
> >
> >       vcpus_complete_new_stage(*current_stage);
> >       pr_info("Started all vCPUs successfully\n");
> > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> > index f1cb1627161f..c252c912f1ba 100644
> > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > @@ -2021,3 +2021,50 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
> >               break;
> >       }
> >  }
> > +
> > +/*
> > + * Create a named thread
> > + *
> > + * Input Args:
>
> thread is missing here
>
> > + *   attr - the attributes for the new thread
> > + *   start_routine - the routine to run in the thread context
> > + *   arg - the argument passed to start_routine
> > + *   name - the name of the thread
> > + *
> > + * Output Args:
> > + *   thread - the thread to be created
> > + *
> > + * Create a thread with user specified name.
> > + */
> > +void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
> > +                     void *(*start_routine)(void *), void *arg, char *name)
> > +{
> > +     int r;
> > +
> > +     r = pthread_create(thread, attr, start_routine, arg);
> > +     TEST_ASSERT(!r, "thread(%s) creation failed, r = %d", name, r);
> > +     pthread_setname_np(*thread, name);
> > +}
> > +
> > +/*
> > + * Create a vcpu thread
> > + *
> > + * Input Args:
>
> thread is missing here
>
> > + *   attr - the attributes for the new thread
> > + *   start_routine - the routine to run in the thread context
> > + *   arg - the argument passed to start_routine
> > + *   vcpu_id - the id of the vcpu
> > + *
> > + * Output Args:
> > + *   thread - the thread to be created
> > + *
> > + * Create a vcpu thread with the name in "vcpu##id" format.
> > + */
> > +void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t *attr,
>
> If I'm reading the patch correctly, attr is always NULL for vCPU
> threads, so just drop it until we need it?
>
> > +                     void *(*start_routine)(void *), void *arg, int vcpu_id)
>
> I think it would be helpful to tie the vcpu_id to something real, rather
> than leaving it up to the caller. How about passing in the struct
> kvm_vcpu here and using vcpu->id in the thread name?
>
> Another cleanup we could do on top of this series would be to stash the
> vCPU pthread_t into struct kvm_vcpu, which would eliminate another
> parameter here and make this API super clean:
>
> void vcpu_create_thread(struct kvm_vcpu *vcpu, void *(*fn)(void *), void *arg)
> {
>         ...
> }
>
> > +{
> > +     char vcpu_name[6];
> > +
> > +     sprintf(vcpu_name, "%s%d", "vcpu", vcpu_id);
>
> There's no need to dynamically insert "vcpu". Also, could we include a
> dash to make the name slightly easier to parse? Putting it together...
>
>         char vcpu_name[16];
>
>         sprintf(vcpu_name, "vcpu-%d", vcpu_id);

Oh and I forgot to mention, vcpu_name[6] is too small of a buffer
since there can be more than 10 vCPUs (honestly, even more than 100 is
quite normal).

>
> > +     pthread_create_with_name(thread, attr, start_routine, arg, vcpu_name);
> > +}
> > diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c
> > index 9618b37c66f7..4e57181daffc 100644
> > --- a/tools/testing/selftests/kvm/lib/perf_test_util.c
> > +++ b/tools/testing/selftests/kvm/lib/perf_test_util.c
> > @@ -274,7 +274,8 @@ void perf_test_start_vcpu_threads(int nr_vcpus,
> >               vcpu->vcpu_idx = i;
> >               WRITE_ONCE(vcpu->running, false);
> >
> > -             pthread_create(&vcpu->thread, NULL, vcpu_thread_main, vcpu);
> > +             kvm_create_vcpu_thread(&vcpu->thread, NULL,
> > +                                    vcpu_thread_main, vcpu, i);
> >       }
> >
> >       for (i = 0; i < nr_vcpus; i++) {
> > diff --git a/tools/testing/selftests/kvm/max_guest_memory_test.c b/tools/testing/selftests/kvm/max_guest_memory_test.c
> > index 9a6e4f3ad6b5..04524694e2b6 100644
> > --- a/tools/testing/selftests/kvm/max_guest_memory_test.c
> > +++ b/tools/testing/selftests/kvm/max_guest_memory_test.c
> > @@ -3,7 +3,6 @@
> >
> >  #include <stdio.h>
> >  #include <stdlib.h>
> > -#include <pthread.h>
> >  #include <semaphore.h>
> >  #include <sys/types.h>
> >  #include <signal.h>
> > @@ -110,7 +109,8 @@ static pthread_t *spawn_workers(struct kvm_vm *vm, struct kvm_vcpu **vcpus,
> >               info[i].vcpu = vcpus[i];
> >               info[i].start_gpa = gpa;
> >               info[i].end_gpa = gpa + nr_bytes;
> > -             pthread_create(&threads[i], NULL, vcpu_worker, &info[i]);
> > +             kvm_create_vcpu_thread(&threads[i], NULL,
> > +                                    vcpu_worker, &info[i], i);
> >       }
> >       return threads;
> >  }
> > diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
> > index 6ee7e1dde404..769300181597 100644
> > --- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c
> > +++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
> > @@ -16,7 +16,6 @@
> >  #include <asm/unistd.h>
> >  #include <time.h>
> >  #include <poll.h>
> > -#include <pthread.h>
> >  #include <linux/bitmap.h>
> >  #include <linux/bitops.h>
> >  #include <linux/userfaultfd.h>
> > diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c
> > index 44995446d942..041a07acba3d 100644
> > --- a/tools/testing/selftests/kvm/memslot_perf_test.c
> > +++ b/tools/testing/selftests/kvm/memslot_perf_test.c
> > @@ -6,7 +6,6 @@
> >   *
> >   * Basic guest setup / host vCPU thread code lifted from set_memory_region_test.
> >   */
> > -#include <pthread.h>
> >  #include <sched.h>
> >  #include <semaphore.h>
> >  #include <stdatomic.h>
> > @@ -332,7 +331,7 @@ static void launch_vm(struct vm_data *data)
> >  {
> >       pr_info_v("Launching the test VM\n");
> >
> > -     pthread_create(&data->vcpu_thread, NULL, vcpu_worker, data);
> > +     kvm_create_vcpu_thread(&data->vcpu_thread, NULL, vcpu_worker, data, 0);
> >
> >       /* Ensure the guest thread is spun up. */
> >       wait_for_vcpu();
> > diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
> > index 6f88da7e60be..11e0b1b7abb1 100644
> > --- a/tools/testing/selftests/kvm/rseq_test.c
> > +++ b/tools/testing/selftests/kvm/rseq_test.c
> > @@ -2,7 +2,6 @@
> >  #define _GNU_SOURCE /* for program_invocation_short_name */
> >  #include <errno.h>
> >  #include <fcntl.h>
> > -#include <pthread.h>
> >  #include <sched.h>
> >  #include <stdio.h>
> >  #include <stdlib.h>
> > @@ -226,8 +225,8 @@ int main(int argc, char *argv[])
> >       vm = vm_create_with_one_vcpu(&vcpu, guest_code);
> >       ucall_init(vm, NULL);
> >
> > -     pthread_create(&migration_thread, NULL, migration_worker,
> > -                    (void *)(unsigned long)syscall(SYS_gettid));
> > +     pthread_create_with_name(&migration_thread, NULL, migration_worker,
> > +            (void *)(unsigned long)syscall(SYS_gettid), "migration-thread");
> >
> >       for (i = 0; !done; i++) {
> >               vcpu_run(vcpu);
> > diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
> > index 0d55f508d595..4c9ab5595a22 100644
> > --- a/tools/testing/selftests/kvm/set_memory_region_test.c
> > +++ b/tools/testing/selftests/kvm/set_memory_region_test.c
> > @@ -1,7 +1,6 @@
> >  // SPDX-License-Identifier: GPL-2.0
> >  #define _GNU_SOURCE /* for program_invocation_short_name */
> >  #include <fcntl.h>
> > -#include <pthread.h>
> >  #include <sched.h>
> >  #include <semaphore.h>
> >  #include <signal.h>
> > @@ -134,7 +133,7 @@ static struct kvm_vm *spawn_vm(struct kvm_vcpu **vcpu, pthread_t *vcpu_thread,
> >       hva = addr_gpa2hva(vm, MEM_REGION_GPA);
> >       memset(hva, 0, 2 * 4096);
> >
> > -     pthread_create(vcpu_thread, NULL, vcpu_worker, *vcpu);
> > +     kvm_create_vcpu_thread(vcpu_thread, NULL, vcpu_worker, *vcpu, 0);
> >
> >       /* Ensure the guest thread is spun up. */
> >       wait_for_vcpu();
> > diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
> > index db8967f1a17b..be93a333ce04 100644
> > --- a/tools/testing/selftests/kvm/steal_time.c
> > +++ b/tools/testing/selftests/kvm/steal_time.c
> > @@ -8,7 +8,6 @@
> >  #include <stdio.h>
> >  #include <time.h>
> >  #include <sched.h>
> > -#include <pthread.h>
> >  #include <linux/kernel.h>
> >  #include <asm/kvm.h>
> >  #include <asm/kvm_para.h>
> > @@ -290,7 +289,8 @@ int main(int ac, char **av)
> >
> >               /* Steal time from the VCPU. The steal time thread has the same CPU affinity as the VCPUs. */
> >               run_delay = get_run_delay();
> > -             pthread_create(&thread, &attr, do_steal_time, NULL);
> > +             pthread_create_with_name(&thread, &attr, do_steal_time,
> > +                                      NULL, "steal-time-thread");
> >               do
> >                       sched_yield();
> >               while (get_run_delay() - run_delay < MIN_RUN_DELAY_NS);
> > diff --git a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
> > index fb02581953a3..abbd5a4f2828 100644
> > --- a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
> > +++ b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
> > @@ -16,7 +16,6 @@
> >  #include <kvm_util.h>
> >  #include <linux/kvm.h>
> >  #include <processor.h>
> > -#include <pthread.h>
> >  #include <stdio.h>
> >  #include <stdlib.h>
> >  #include <string.h>
> > @@ -69,7 +68,7 @@ void test(void)
> >       tc.run = run;
> >       srand(getpid());
> >       for (i = 0; i < NTHREAD; i++) {
> > -             pthread_create(&th[i], NULL, thr, (void *)(uintptr_t)&tc);
> > +             kvm_create_vcpu_thread(&th[i], NULL, thr, (void *)(uintptr_t)&tc, i);
> >               usleep(rand() % 10000);
> >       }
> >       for (i = 0; i < NTHREAD; i++)
> > diff --git a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > index c7ef97561038..b00ba08a19eb 100644
> > --- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > +++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
> > @@ -5,7 +5,6 @@
> >  #include <sys/ioctl.h>
> >  #include <stdlib.h>
> >  #include <errno.h>
> > -#include <pthread.h>
> >
> >  #include "test_util.h"
> >  #include "kvm_util.h"
> > diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
> > index 47139aab7408..a6511c399173 100644
> > --- a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
> > +++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
> > @@ -15,7 +15,6 @@
> >  #include <time.h>
> >  #include <sched.h>
> >  #include <signal.h>
> > -#include <pthread.h>
> >
> >  #define NR_TEST_VCPUS 20
> >
> > @@ -102,7 +101,8 @@ int main(int argc, char *argv[])
> >       pthread_t cpu_threads[NR_TEST_VCPUS];
> >       unsigned long cpu;
> >       for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++)
> > -             pthread_create(&cpu_threads[cpu], NULL, run_vcpu, (void *)cpu);
> > +             kvm_create_vcpu_thread(&cpu_threads[cpu], NULL,
> > +                                    run_vcpu, (void *)cpu, cpu);
> >
> >       unsigned long failures = 0;
> >       for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) {
> > diff --git a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
> > index a897c7fd8abe..24a89a3a11db 100644
> > --- a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
> > +++ b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
> > @@ -19,7 +19,6 @@
> >   */
> >
> >  #define _GNU_SOURCE /* for program_invocation_short_name */
> > -#include <pthread.h>
> >  #include <inttypes.h>
> >  #include <string.h>
> >  #include <time.h>
> > diff --git a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
> > index 3d272d7f961e..8bdef8e0f2b0 100644
> > --- a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
> > +++ b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
> > @@ -22,7 +22,6 @@
> >
> >  #define _GNU_SOURCE /* for program_invocation_short_name */
> >  #include <getopt.h>
> > -#include <pthread.h>
> >  #include <inttypes.h>
> >  #include <string.h>
> >  #include <time.h>
> > @@ -393,7 +392,6 @@ void get_cmdline_args(int argc, char *argv[], int *run_secs,
> >
> >  int main(int argc, char *argv[])
> >  {
> > -     int r;
> >       int wait_secs;
> >       const int max_halter_wait = 10;
> >       int run_secs = 0;
> > @@ -436,9 +434,8 @@ int main(int argc, char *argv[])
> >       params[1].pipis_rcvd = pipis_rcvd;
> >
> >       /* Start halter vCPU thread and wait for it to execute first HLT. */
> > -     r = pthread_create(&threads[0], NULL, vcpu_thread, &params[0]);
> > -     TEST_ASSERT(r == 0,
> > -                 "pthread_create halter failed errno=%d", errno);
> > +     kvm_create_vcpu_thread(&threads[0], NULL,
> > +                            vcpu_thread, &params[0], 0);
> >       fprintf(stderr, "Halter vCPU thread started\n");
> >
> >       wait_secs = 0;
> > @@ -455,8 +452,7 @@ int main(int argc, char *argv[])
> >               "Halter vCPU thread reported its APIC ID: %u after %d seconds.\n",
> >               data->halter_apic_id, wait_secs);
> >
> > -     r = pthread_create(&threads[1], NULL, vcpu_thread, &params[1]);
> > -     TEST_ASSERT(r == 0, "pthread_create sender failed errno=%d", errno);
> > +     kvm_create_vcpu_thread(&threads[1], NULL, vcpu_thread, &params[1], 1);
> >
> >       fprintf(stderr,
> >               "IPI sender vCPU thread started. Letting vCPUs run for %d seconds.\n",
> > --
> > 2.27.0
> >
  
Wang, Wei W Oct. 20, 2022, 11:37 a.m. UTC | #3
On Thursday, October 20, 2022 1:29 AM, David Matlack wrote:
> > +/*
> > + * Create a named thread
> > + *
> > + * Input Args:
> 
> thread is missing here

It's an output, I think.

> 
> > + *   attr - the attributes for the new thread
> > + *   start_routine - the routine to run in the thread context
> > + *   arg - the argument passed to start_routine
> > + *   vcpu_id - the id of the vcpu
> > + *
> > + * Output Args:
> > + *   thread - the thread to be created
> > + *
> > + * Create a vcpu thread with the name in "vcpu##id" format.
> > + */
> > +void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t
> > +*attr,
> 
> If I'm reading the patch correctly, attr is always NULL for vCPU threads, so just
> drop it until we need it?

Yeah, sounds good.

> 
> > +			void *(*start_routine)(void *), void *arg, int vcpu_id)
> 
> I think it would be helpful to tie the vcpu_id to something real, rather than
> leaving it up to the caller. How about passing in the struct kvm_vcpu here and
> using vcpu->id in the thread name?

Yes, with the cleanup you mentioned below, it would be better.

> 
> Another cleanup we could do on top of this series would be to stash the vCPU
> pthread_t into struct kvm_vcpu, 

Yes, I also thought about this when I made this patch. I have other optimizations along
with this change, and this will have a lot more changes, but we will get much better code
consolidation. Let me post them together in v2 to discuss.

> which would eliminate another parameter here
> and make this API super clean:
> 
> void vcpu_create_thread(struct kvm_vcpu *vcpu, void *(*fn)(void *), void *arg) {
> 	...
> }
> > +{
> > +	char vcpu_name[6];
> > +
> > +	sprintf(vcpu_name, "%s%d", "vcpu", vcpu_id);
> 
> There's no need to dynamically insert "vcpu". Also, could we include a dash to
> make the name slightly easier to parse? Putting it together...

Right ;)
Thanks!
  
Vipin Sharma Oct. 21, 2022, 10:34 p.m. UTC | #4
On Mon, Oct 17, 2022 at 9:25 AM Wei Wang <wei.w.wang@intel.com> wrote:
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index f1cb1627161f..c252c912f1ba 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -2021,3 +2021,50 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
>                 break;
>         }
>  }
> +
> +/*
> + * Create a named thread
> + *
> + * Input Args:
> + *   attr - the attributes for the new thread
> + *   start_routine - the routine to run in the thread context
> + *   arg - the argument passed to start_routine
> + *   name - the name of the thread
> + *
> + * Output Args:
> + *   thread - the thread to be created
> + *
> + * Create a thread with user specified name.
> + */
> +void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
> +                       void *(*start_routine)(void *), void *arg, char *name)
> +{
> +       int r;
> +
> +       r = pthread_create(thread, attr, start_routine, arg);
> +       TEST_ASSERT(!r, "thread(%s) creation failed, r = %d", name, r);
> +       pthread_setname_np(*thread, name);

Since pthread_setname_np() expects "name" to be 16 chars including \0,
maybe a strnlen(name, 16) check before it will be useful.
  
Wang, Wei W Oct. 24, 2022, 12:54 a.m. UTC | #5
On Saturday, October 22, 2022 6:34 AM, Vipin Sharma wrote:
> On Mon, Oct 17, 2022 at 9:25 AM Wei Wang <wei.w.wang@intel.com> wrote:
> > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c
> > b/tools/testing/selftests/kvm/lib/kvm_util.c
> > index f1cb1627161f..c252c912f1ba 100644
> > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > @@ -2021,3 +2021,50 @@ void __vm_get_stat(struct kvm_vm *vm, const
> char *stat_name, uint64_t *data,
> >                 break;
> >         }
> >  }
> > +
> > +/*
> > + * Create a named thread
> > + *
> > + * Input Args:
> > + *   attr - the attributes for the new thread
> > + *   start_routine - the routine to run in the thread context
> > + *   arg - the argument passed to start_routine
> > + *   name - the name of the thread
> > + *
> > + * Output Args:
> > + *   thread - the thread to be created
> > + *
> > + * Create a thread with user specified name.
> > + */
> > +void pthread_create_with_name(pthread_t *thread, const pthread_attr_t
> *attr,
> > +                       void *(*start_routine)(void *), void *arg,
> > +char *name) {
> > +       int r;
> > +
> > +       r = pthread_create(thread, attr, start_routine, arg);
> > +       TEST_ASSERT(!r, "thread(%s) creation failed, r = %d", name, r);
> > +       pthread_setname_np(*thread, name);
> 
> Since pthread_setname_np() expects "name" to be 16 chars including \0,
> maybe a strnlen(name, 16) check before it will be useful.

Yes. Alternatively, we should just check the return value of pthread_setname_np
and assert on any errors.
  

Patch

diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
index 574eb73f0e90..14f56327ca28 100644
--- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
+++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
@@ -23,7 +23,6 @@ 
 #define _GNU_SOURCE
 
 #include <stdlib.h>
-#include <pthread.h>
 #include <linux/kvm.h>
 #include <linux/sizes.h>
 #include <linux/bitmap.h>
@@ -314,28 +313,23 @@  static void test_run(struct kvm_vm *vm)
 {
 	pthread_t pt_vcpu_migration;
 	unsigned int i;
-	int ret;
 
 	pthread_mutex_init(&vcpu_done_map_lock, NULL);
 	vcpu_done_map = bitmap_zalloc(test_args.nr_vcpus);
 	TEST_ASSERT(vcpu_done_map, "Failed to allocate vcpu done bitmap\n");
 
-	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++) {
-		ret = pthread_create(&pt_vcpu_run[i], NULL, test_vcpu_run,
-				     (void *)(unsigned long)i);
-		TEST_ASSERT(!ret, "Failed to create vCPU-%d pthread\n", i);
-	}
+	for (i = 0; i < (unsigned long)test_args.nr_vcpus; i++)
+		kvm_create_vcpu_thread(&pt_vcpu_run[i], NULL,
+				test_vcpu_run, (void *)(unsigned long)i, i);
 
 	/* Spawn a thread to control the vCPU migrations */
 	if (test_args.migration_freq_ms) {
 		srand(time(NULL));
 
-		ret = pthread_create(&pt_vcpu_migration, NULL,
-					test_vcpu_migration, NULL);
-		TEST_ASSERT(!ret, "Failed to create the migration pthread\n");
+		pthread_create_with_name(&pt_vcpu_migration, NULL,
+				test_vcpu_migration, NULL, "control-thread");
 	}
 
-
 	for (i = 0; i < test_args.nr_vcpus; i++)
 		pthread_join(pt_vcpu_run[i], NULL);
 
diff --git a/tools/testing/selftests/kvm/access_tracking_perf_test.c b/tools/testing/selftests/kvm/access_tracking_perf_test.c
index 76c583a07ea2..b61ecc907d61 100644
--- a/tools/testing/selftests/kvm/access_tracking_perf_test.c
+++ b/tools/testing/selftests/kvm/access_tracking_perf_test.c
@@ -37,7 +37,6 @@ 
  */
 #include <inttypes.h>
 #include <limits.h>
-#include <pthread.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/stat.h>
diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
index 779ae54f89c4..f75d531008e8 100644
--- a/tools/testing/selftests/kvm/demand_paging_test.c
+++ b/tools/testing/selftests/kvm/demand_paging_test.c
@@ -14,7 +14,6 @@ 
 #include <stdlib.h>
 #include <time.h>
 #include <poll.h>
-#include <pthread.h>
 #include <linux/userfaultfd.h>
 #include <sys/syscall.h>
 
@@ -260,8 +259,8 @@  static void setup_demand_paging(struct kvm_vm *vm,
 	uffd_args->uffd = uffd;
 	uffd_args->pipefd = pipefd;
 	uffd_args->delay = uffd_delay;
-	pthread_create(uffd_handler_thread, NULL, uffd_handler_thread_fn,
-		       uffd_args);
+	pthread_create_with_name(uffd_handler_thread, NULL,
+		uffd_handler_thread_fn, uffd_args, "uffd-handler-thread");
 
 	PER_VCPU_DEBUG("Created uffd thread for HVA range [%p, %p)\n",
 		       hva, hva + len);
diff --git a/tools/testing/selftests/kvm/dirty_log_perf_test.c b/tools/testing/selftests/kvm/dirty_log_perf_test.c
index f99e39a672d3..5cf9080b3864 100644
--- a/tools/testing/selftests/kvm/dirty_log_perf_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_perf_test.c
@@ -11,7 +11,6 @@ 
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
-#include <pthread.h>
 #include <linux/bitmap.h>
 
 #include "kvm_util.h"
diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index b5234d6efbe1..c7a30b4dd33a 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -772,7 +772,7 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 	host_clear_count = 0;
 	host_track_next_count = 0;
 
-	pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);
+	kvm_create_vcpu_thread(&vcpu_thread, NULL, vcpu_worker, vcpu, 0);
 
 	while (iteration < p->iterations) {
 		/* Give the vcpu thread some time to dirty some pages */
diff --git a/tools/testing/selftests/kvm/hardware_disable_test.c b/tools/testing/selftests/kvm/hardware_disable_test.c
index f5d59b9934f1..c22b8445a809 100644
--- a/tools/testing/selftests/kvm/hardware_disable_test.c
+++ b/tools/testing/selftests/kvm/hardware_disable_test.c
@@ -8,7 +8,6 @@ 
 #define _GNU_SOURCE
 
 #include <fcntl.h>
-#include <pthread.h>
 #include <semaphore.h>
 #include <stdint.h>
 #include <stdlib.h>
@@ -59,15 +58,6 @@  static void *sleeping_thread(void *arg)
 	pthread_exit(NULL);
 }
 
-static inline void check_create_thread(pthread_t *thread, pthread_attr_t *attr,
-				       void *(*f)(void *), void *arg)
-{
-	int r;
-
-	r = pthread_create(thread, attr, f, arg);
-	TEST_ASSERT(r == 0, "%s: failed to create thread", __func__);
-}
-
 static inline void check_set_affinity(pthread_t thread, cpu_set_t *cpu_set)
 {
 	int r;
@@ -104,12 +94,13 @@  static void run_test(uint32_t run)
 	for (i = 0; i < VCPU_NUM; ++i) {
 		vcpu = vm_vcpu_add(vm, i, guest_code);
 
-		check_create_thread(&threads[i], NULL, run_vcpu, vcpu);
+		kvm_create_vcpu_thread(&threads[i], NULL, run_vcpu, vcpu, i);
 		check_set_affinity(threads[i], &cpu_set);
 
 		for (j = 0; j < SLEEPING_THREAD_NUM; ++j) {
-			check_create_thread(&throw_away, NULL, sleeping_thread,
-					    (void *)NULL);
+			pthread_create_with_name(&throw_away, NULL,
+						 sleeping_thread, (void *)NULL,
+						 "sleeping-thread");
 			check_set_affinity(throw_away, &cpu_set);
 		}
 	}
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index c9286811a4cb..b7f0295d928e 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -7,7 +7,15 @@ 
 #ifndef SELFTEST_KVM_UTIL_H
 #define SELFTEST_KVM_UTIL_H
 
+#include <pthread.h>
+
 #include "kvm_util_base.h"
 #include "ucall_common.h"
 
+void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
+			void *(*start_routine)(void *), void *arg, char *name);
+
+void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t *attr,
+		void *(*start_routine)(void *), void *arg, int vcpu_id);
+
 #endif /* SELFTEST_KVM_UTIL_H */
diff --git a/tools/testing/selftests/kvm/include/perf_test_util.h b/tools/testing/selftests/kvm/include/perf_test_util.h
index eaa88df0555a..cb6971c8740f 100644
--- a/tools/testing/selftests/kvm/include/perf_test_util.h
+++ b/tools/testing/selftests/kvm/include/perf_test_util.h
@@ -8,8 +8,6 @@ 
 #ifndef SELFTEST_KVM_PERF_TEST_UTIL_H
 #define SELFTEST_KVM_PERF_TEST_UTIL_H
 
-#include <pthread.h>
-
 #include "kvm_util.h"
 
 /* Default guest test virtual memory offset */
diff --git a/tools/testing/selftests/kvm/kvm_page_table_test.c b/tools/testing/selftests/kvm/kvm_page_table_test.c
index f42c6ac6d71d..1e41dca7f67d 100644
--- a/tools/testing/selftests/kvm/kvm_page_table_test.c
+++ b/tools/testing/selftests/kvm/kvm_page_table_test.c
@@ -14,7 +14,6 @@ 
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
-#include <pthread.h>
 #include <semaphore.h>
 
 #include "test_util.h"
@@ -359,8 +358,8 @@  static void run_test(enum vm_guest_mode mode, void *arg)
 	*current_stage = KVM_BEFORE_MAPPINGS;
 
 	for (i = 0; i < nr_vcpus; i++)
-		pthread_create(&vcpu_threads[i], NULL, vcpu_worker,
-			       test_args.vcpus[i]);
+		kvm_create_vcpu_thread(&vcpu_threads[i], NULL,
+				       vcpu_worker, test_args.vcpus[i], i);
 
 	vcpus_complete_new_stage(*current_stage);
 	pr_info("Started all vCPUs successfully\n");
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index f1cb1627161f..c252c912f1ba 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -2021,3 +2021,50 @@  void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
 		break;
 	}
 }
+
+/*
+ * Create a named thread
+ *
+ * Input Args:
+ *   attr - the attributes for the new thread
+ *   start_routine - the routine to run in the thread context
+ *   arg - the argument passed to start_routine
+ *   name - the name of the thread
+ *
+ * Output Args:
+ *   thread - the thread to be created
+ *
+ * Create a thread with user specified name.
+ */
+void pthread_create_with_name(pthread_t *thread, const pthread_attr_t *attr,
+			void *(*start_routine)(void *), void *arg, char *name)
+{
+	int r;
+
+	r = pthread_create(thread, attr, start_routine, arg);
+	TEST_ASSERT(!r, "thread(%s) creation failed, r = %d", name, r);
+	pthread_setname_np(*thread, name);
+}
+
+/*
+ * Create a vcpu thread
+ *
+ * Input Args:
+ *   attr - the attributes for the new thread
+ *   start_routine - the routine to run in the thread context
+ *   arg - the argument passed to start_routine
+ *   vcpu_id - the id of the vcpu
+ *
+ * Output Args:
+ *   thread - the thread to be created
+ *
+ * Create a vcpu thread with the name in "vcpu##id" format.
+ */
+void kvm_create_vcpu_thread(pthread_t *thread, const pthread_attr_t *attr,
+			void *(*start_routine)(void *), void *arg, int vcpu_id)
+{
+	char vcpu_name[6];
+
+	sprintf(vcpu_name, "%s%d", "vcpu", vcpu_id);
+	pthread_create_with_name(thread, attr, start_routine, arg, vcpu_name);
+}
diff --git a/tools/testing/selftests/kvm/lib/perf_test_util.c b/tools/testing/selftests/kvm/lib/perf_test_util.c
index 9618b37c66f7..4e57181daffc 100644
--- a/tools/testing/selftests/kvm/lib/perf_test_util.c
+++ b/tools/testing/selftests/kvm/lib/perf_test_util.c
@@ -274,7 +274,8 @@  void perf_test_start_vcpu_threads(int nr_vcpus,
 		vcpu->vcpu_idx = i;
 		WRITE_ONCE(vcpu->running, false);
 
-		pthread_create(&vcpu->thread, NULL, vcpu_thread_main, vcpu);
+		kvm_create_vcpu_thread(&vcpu->thread, NULL,
+				       vcpu_thread_main, vcpu, i);
 	}
 
 	for (i = 0; i < nr_vcpus; i++) {
diff --git a/tools/testing/selftests/kvm/max_guest_memory_test.c b/tools/testing/selftests/kvm/max_guest_memory_test.c
index 9a6e4f3ad6b5..04524694e2b6 100644
--- a/tools/testing/selftests/kvm/max_guest_memory_test.c
+++ b/tools/testing/selftests/kvm/max_guest_memory_test.c
@@ -3,7 +3,6 @@ 
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <pthread.h>
 #include <semaphore.h>
 #include <sys/types.h>
 #include <signal.h>
@@ -110,7 +109,8 @@  static pthread_t *spawn_workers(struct kvm_vm *vm, struct kvm_vcpu **vcpus,
 		info[i].vcpu = vcpus[i];
 		info[i].start_gpa = gpa;
 		info[i].end_gpa = gpa + nr_bytes;
-		pthread_create(&threads[i], NULL, vcpu_worker, &info[i]);
+		kvm_create_vcpu_thread(&threads[i], NULL,
+				       vcpu_worker, &info[i], i);
 	}
 	return threads;
 }
diff --git a/tools/testing/selftests/kvm/memslot_modification_stress_test.c b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
index 6ee7e1dde404..769300181597 100644
--- a/tools/testing/selftests/kvm/memslot_modification_stress_test.c
+++ b/tools/testing/selftests/kvm/memslot_modification_stress_test.c
@@ -16,7 +16,6 @@ 
 #include <asm/unistd.h>
 #include <time.h>
 #include <poll.h>
-#include <pthread.h>
 #include <linux/bitmap.h>
 #include <linux/bitops.h>
 #include <linux/userfaultfd.h>
diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c
index 44995446d942..041a07acba3d 100644
--- a/tools/testing/selftests/kvm/memslot_perf_test.c
+++ b/tools/testing/selftests/kvm/memslot_perf_test.c
@@ -6,7 +6,6 @@ 
  *
  * Basic guest setup / host vCPU thread code lifted from set_memory_region_test.
  */
-#include <pthread.h>
 #include <sched.h>
 #include <semaphore.h>
 #include <stdatomic.h>
@@ -332,7 +331,7 @@  static void launch_vm(struct vm_data *data)
 {
 	pr_info_v("Launching the test VM\n");
 
-	pthread_create(&data->vcpu_thread, NULL, vcpu_worker, data);
+	kvm_create_vcpu_thread(&data->vcpu_thread, NULL, vcpu_worker, data, 0);
 
 	/* Ensure the guest thread is spun up. */
 	wait_for_vcpu();
diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
index 6f88da7e60be..11e0b1b7abb1 100644
--- a/tools/testing/selftests/kvm/rseq_test.c
+++ b/tools/testing/selftests/kvm/rseq_test.c
@@ -2,7 +2,6 @@ 
 #define _GNU_SOURCE /* for program_invocation_short_name */
 #include <errno.h>
 #include <fcntl.h>
-#include <pthread.h>
 #include <sched.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -226,8 +225,8 @@  int main(int argc, char *argv[])
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
 	ucall_init(vm, NULL);
 
-	pthread_create(&migration_thread, NULL, migration_worker,
-		       (void *)(unsigned long)syscall(SYS_gettid));
+	pthread_create_with_name(&migration_thread, NULL, migration_worker,
+	       (void *)(unsigned long)syscall(SYS_gettid), "migration-thread");
 
 	for (i = 0; !done; i++) {
 		vcpu_run(vcpu);
diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index 0d55f508d595..4c9ab5595a22 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -1,7 +1,6 @@ 
 // SPDX-License-Identifier: GPL-2.0
 #define _GNU_SOURCE /* for program_invocation_short_name */
 #include <fcntl.h>
-#include <pthread.h>
 #include <sched.h>
 #include <semaphore.h>
 #include <signal.h>
@@ -134,7 +133,7 @@  static struct kvm_vm *spawn_vm(struct kvm_vcpu **vcpu, pthread_t *vcpu_thread,
 	hva = addr_gpa2hva(vm, MEM_REGION_GPA);
 	memset(hva, 0, 2 * 4096);
 
-	pthread_create(vcpu_thread, NULL, vcpu_worker, *vcpu);
+	kvm_create_vcpu_thread(vcpu_thread, NULL, vcpu_worker, *vcpu, 0);
 
 	/* Ensure the guest thread is spun up. */
 	wait_for_vcpu();
diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
index db8967f1a17b..be93a333ce04 100644
--- a/tools/testing/selftests/kvm/steal_time.c
+++ b/tools/testing/selftests/kvm/steal_time.c
@@ -8,7 +8,6 @@ 
 #include <stdio.h>
 #include <time.h>
 #include <sched.h>
-#include <pthread.h>
 #include <linux/kernel.h>
 #include <asm/kvm.h>
 #include <asm/kvm_para.h>
@@ -290,7 +289,8 @@  int main(int ac, char **av)
 
 		/* Steal time from the VCPU. The steal time thread has the same CPU affinity as the VCPUs. */
 		run_delay = get_run_delay();
-		pthread_create(&thread, &attr, do_steal_time, NULL);
+		pthread_create_with_name(&thread, &attr, do_steal_time,
+					 NULL, "steal-time-thread");
 		do
 			sched_yield();
 		while (get_run_delay() - run_delay < MIN_RUN_DELAY_NS);
diff --git a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
index fb02581953a3..abbd5a4f2828 100644
--- a/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
+++ b/tools/testing/selftests/kvm/x86_64/mmio_warning_test.c
@@ -16,7 +16,6 @@ 
 #include <kvm_util.h>
 #include <linux/kvm.h>
 #include <processor.h>
-#include <pthread.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -69,7 +68,7 @@  void test(void)
 	tc.run = run;
 	srand(getpid());
 	for (i = 0; i < NTHREAD; i++) {
-		pthread_create(&th[i], NULL, thr, (void *)(uintptr_t)&tc);
+		kvm_create_vcpu_thread(&th[i], NULL, thr, (void *)(uintptr_t)&tc, i);
 		usleep(rand() % 10000);
 	}
 	for (i = 0; i < NTHREAD; i++)
diff --git a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
index c7ef97561038..b00ba08a19eb 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_migrate_tests.c
@@ -5,7 +5,6 @@ 
 #include <sys/ioctl.h>
 #include <stdlib.h>
 #include <errno.h>
-#include <pthread.h>
 
 #include "test_util.h"
 #include "kvm_util.h"
diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
index 47139aab7408..a6511c399173 100644
--- a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
+++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
@@ -15,7 +15,6 @@ 
 #include <time.h>
 #include <sched.h>
 #include <signal.h>
-#include <pthread.h>
 
 #define NR_TEST_VCPUS 20
 
@@ -102,7 +101,8 @@  int main(int argc, char *argv[])
 	pthread_t cpu_threads[NR_TEST_VCPUS];
 	unsigned long cpu;
 	for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++)
-		pthread_create(&cpu_threads[cpu], NULL, run_vcpu, (void *)cpu);
+		kvm_create_vcpu_thread(&cpu_threads[cpu], NULL,
+				       run_vcpu, (void *)cpu, cpu);
 
 	unsigned long failures = 0;
 	for (cpu = 0; cpu < NR_TEST_VCPUS; cpu++) {
diff --git a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
index a897c7fd8abe..24a89a3a11db 100644
--- a/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
+++ b/tools/testing/selftests/kvm/x86_64/ucna_injection_test.c
@@ -19,7 +19,6 @@ 
  */
 
 #define _GNU_SOURCE /* for program_invocation_short_name */
-#include <pthread.h>
 #include <inttypes.h>
 #include <string.h>
 #include <time.h>
diff --git a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
index 3d272d7f961e..8bdef8e0f2b0 100644
--- a/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xapic_ipi_test.c
@@ -22,7 +22,6 @@ 
 
 #define _GNU_SOURCE /* for program_invocation_short_name */
 #include <getopt.h>
-#include <pthread.h>
 #include <inttypes.h>
 #include <string.h>
 #include <time.h>
@@ -393,7 +392,6 @@  void get_cmdline_args(int argc, char *argv[], int *run_secs,
 
 int main(int argc, char *argv[])
 {
-	int r;
 	int wait_secs;
 	const int max_halter_wait = 10;
 	int run_secs = 0;
@@ -436,9 +434,8 @@  int main(int argc, char *argv[])
 	params[1].pipis_rcvd = pipis_rcvd;
 
 	/* Start halter vCPU thread and wait for it to execute first HLT. */
-	r = pthread_create(&threads[0], NULL, vcpu_thread, &params[0]);
-	TEST_ASSERT(r == 0,
-		    "pthread_create halter failed errno=%d", errno);
+	kvm_create_vcpu_thread(&threads[0], NULL,
+			       vcpu_thread, &params[0], 0);
 	fprintf(stderr, "Halter vCPU thread started\n");
 
 	wait_secs = 0;
@@ -455,8 +452,7 @@  int main(int argc, char *argv[])
 		"Halter vCPU thread reported its APIC ID: %u after %d seconds.\n",
 		data->halter_apic_id, wait_secs);
 
-	r = pthread_create(&threads[1], NULL, vcpu_thread, &params[1]);
-	TEST_ASSERT(r == 0, "pthread_create sender failed errno=%d", errno);
+	kvm_create_vcpu_thread(&threads[1], NULL, vcpu_thread, &params[1], 1);
 
 	fprintf(stderr,
 		"IPI sender vCPU thread started. Letting vCPUs run for %d seconds.\n",