[PATCH v2 090/144] KVM: selftests: Convert dirty_log_test away from VCPU_ID

From: Sean Christopherson
Date: Thu Jun 02 2022 - 20:56:17 EST


Convert dirty_log_test to pass around a 'struct kvm_vcpu' object instead
of using a global VCPU_ID. Note, this is a "functional" change in the
sense that the test now creates a vCPU with vcpu_id==0 instead of
vcpu_id==5. The non-zero VCPU_ID was 100% arbitrary and added little to
no validation coverage. If testing non-zero vCPU IDs is desirable for
generic tests, that can be done in the future by tweaking the VM creation
helpers.

The test still hardcodes usage of vcpu_id==0, but only for a few lines.
That wart will be removed in the not-too-distant future.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
tools/testing/selftests/kvm/dirty_log_test.c | 59 ++++++++++----------
1 file changed, 30 insertions(+), 29 deletions(-)

diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index cf426a8ae816..23e0c727e375 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -23,8 +23,6 @@
#include "guest_modes.h"
#include "processor.h"

-#define VCPU_ID 1
-
/* The memory slot index to track dirty pages */
#define TEST_MEM_SLOT_INDEX 1

@@ -226,17 +224,17 @@ static void clear_log_create_vm_done(struct kvm_vm *vm)
vm_enable_cap(vm, KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2, manual_caps);
}

-static void dirty_log_collect_dirty_pages(struct kvm_vm *vm, int slot,
+static void dirty_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
- kvm_vm_get_dirty_log(vm, slot, bitmap);
+ kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap);
}

-static void clear_log_collect_dirty_pages(struct kvm_vm *vm, int slot,
+static void clear_log_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
- kvm_vm_get_dirty_log(vm, slot, bitmap);
- kvm_vm_clear_dirty_log(vm, slot, bitmap, 0, num_pages);
+ kvm_vm_get_dirty_log(vcpu->vm, slot, bitmap);
+ kvm_vm_clear_dirty_log(vcpu->vm, slot, bitmap, 0, num_pages);
}

/* Should only be called after a GUEST_SYNC */
@@ -250,14 +248,14 @@ static void vcpu_handle_sync_stop(void)
}
}

-static void default_after_vcpu_run(struct kvm_vm *vm, int ret, int err)
+static void default_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct kvm_run *run = vcpu->run;

TEST_ASSERT(ret == 0 || (ret == -1 && err == EINTR),
"vcpu run failed: errno=%d", err);

- TEST_ASSERT(get_ucall(vm, VCPU_ID, NULL) == UCALL_SYNC,
+ TEST_ASSERT(get_ucall(vcpu->vm, vcpu->id, NULL) == UCALL_SYNC,
"Invalid guest sync status: exit_reason=%s\n",
exit_reason_str(run->exit_reason));

@@ -328,7 +326,7 @@ static void dirty_ring_continue_vcpu(void)
sem_post(&sem_vcpu_cont);
}

-static void dirty_ring_collect_dirty_pages(struct kvm_vm *vm, int slot,
+static void dirty_ring_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
/* We only have one vcpu */
@@ -348,10 +346,10 @@ static void dirty_ring_collect_dirty_pages(struct kvm_vm *vm, int slot,
}

/* Only have one vcpu */
- count = dirty_ring_collect_one(vcpu_map_dirty_ring(vm, VCPU_ID),
+ count = dirty_ring_collect_one(vcpu_map_dirty_ring(vcpu->vm, vcpu->id),
slot, bitmap, num_pages, &fetch_index);

- cleared = kvm_vm_reset_dirty_ring(vm);
+ cleared = kvm_vm_reset_dirty_ring(vcpu->vm);

/* Cleared pages should be the same as collected */
TEST_ASSERT(cleared == count, "Reset dirty pages (%u) mismatch "
@@ -366,12 +364,12 @@ static void dirty_ring_collect_dirty_pages(struct kvm_vm *vm, int slot,
pr_info("Iteration %ld collected %u pages\n", iteration, count);
}

-static void dirty_ring_after_vcpu_run(struct kvm_vm *vm, int ret, int err)
+static void dirty_ring_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
{
- struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+ struct kvm_run *run = vcpu->run;

/* A ucall-sync or ring-full event is allowed */
- if (get_ucall(vm, VCPU_ID, NULL) == UCALL_SYNC) {
+ if (get_ucall(vcpu->vm, vcpu->id, NULL) == UCALL_SYNC) {
/* We should allow this to continue */
;
} else if (run->exit_reason == KVM_EXIT_DIRTY_RING_FULL ||
@@ -405,10 +403,10 @@ struct log_mode {
/* Hook when the vm creation is done (before vcpu creation) */
void (*create_vm_done)(struct kvm_vm *vm);
/* Hook to collect the dirty pages into the bitmap provided */
- void (*collect_dirty_pages) (struct kvm_vm *vm, int slot,
+ void (*collect_dirty_pages) (struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages);
/* Hook to call when after each vcpu run */
- void (*after_vcpu_run)(struct kvm_vm *vm, int ret, int err);
+ void (*after_vcpu_run)(struct kvm_vcpu *vcpu, int ret, int err);
void (*before_vcpu_join) (void);
} log_modes[LOG_MODE_NUM] = {
{
@@ -470,22 +468,22 @@ static void log_mode_create_vm_done(struct kvm_vm *vm)
mode->create_vm_done(vm);
}

-static void log_mode_collect_dirty_pages(struct kvm_vm *vm, int slot,
+static void log_mode_collect_dirty_pages(struct kvm_vcpu *vcpu, int slot,
void *bitmap, uint32_t num_pages)
{
struct log_mode *mode = &log_modes[host_log_mode];

TEST_ASSERT(mode->collect_dirty_pages != NULL,
"collect_dirty_pages() is required for any log mode!");
- mode->collect_dirty_pages(vm, slot, bitmap, num_pages);
+ mode->collect_dirty_pages(vcpu, slot, bitmap, num_pages);
}

-static void log_mode_after_vcpu_run(struct kvm_vm *vm, int ret, int err)
+static void log_mode_after_vcpu_run(struct kvm_vcpu *vcpu, int ret, int err)
{
struct log_mode *mode = &log_modes[host_log_mode];

if (mode->after_vcpu_run)
- mode->after_vcpu_run(vm, ret, err);
+ mode->after_vcpu_run(vcpu, ret, err);
}

static void log_mode_before_vcpu_join(void)
@@ -507,7 +505,8 @@ static void generate_random_array(uint64_t *guest_array, uint64_t size)
static void *vcpu_worker(void *data)
{
int ret;
- struct kvm_vm *vm = data;
+ struct kvm_vcpu *vcpu = data;
+ struct kvm_vm *vm = vcpu->vm;
uint64_t *guest_array;
uint64_t pages_count = 0;
struct kvm_signal_mask *sigmask = alloca(offsetof(struct kvm_signal_mask, sigset)
@@ -522,7 +521,7 @@ static void *vcpu_worker(void *data)
sigmask->len = 8;
pthread_sigmask(0, NULL, sigset);
sigdelset(sigset, SIG_IPI);
- vcpu_ioctl(vm, VCPU_ID, KVM_SET_SIGNAL_MASK, sigmask);
+ vcpu_ioctl(vm, vcpu->id, KVM_SET_SIGNAL_MASK, sigmask);

sigemptyset(sigset);
sigaddset(sigset, SIG_IPI);
@@ -534,13 +533,13 @@ static void *vcpu_worker(void *data)
generate_random_array(guest_array, TEST_PAGES_PER_LOOP);
pages_count += TEST_PAGES_PER_LOOP;
/* Let the guest dirty the random pages */
- ret = __vcpu_run(vm, VCPU_ID);
+ ret = __vcpu_run(vm, vcpu->id);
if (ret == -1 && errno == EINTR) {
int sig = -1;
sigwait(sigset, &sig);
assert(sig == SIG_IPI);
}
- log_mode_after_vcpu_run(vm, ret, errno);
+ log_mode_after_vcpu_run(vcpu, ret, errno);
}

pr_info("Dirtied %"PRIu64" pages\n", pages_count);
@@ -693,6 +692,7 @@ struct test_params {
static void run_test(enum vm_guest_mode mode, void *arg)
{
struct test_params *p = arg;
+ struct kvm_vcpu *vcpu;
struct kvm_vm *vm;
unsigned long *bmap;

@@ -710,9 +710,10 @@ static void run_test(enum vm_guest_mode mode, void *arg)
* (e.g., 64K page size guest will need even less memory for
* page tables).
*/
- vm = create_vm(mode, VCPU_ID,
+ vm = create_vm(mode, 0,
2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K),
guest_code);
+ vcpu = vcpu_get(vm, 0);

guest_page_size = vm_get_page_size(vm);
/*
@@ -773,12 +774,12 @@ 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, vm);
+ pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);

while (iteration < p->iterations) {
/* Give the vcpu thread some time to dirty some pages */
usleep(p->interval * 1000);
- log_mode_collect_dirty_pages(vm, TEST_MEM_SLOT_INDEX,
+ log_mode_collect_dirty_pages(vcpu, TEST_MEM_SLOT_INDEX,
bmap, host_num_pages);

/*
--
2.36.1.255.ge46751e96f-goog