Add a new arch_timer_edge_cases selftests that validates:
- timers above the max TVAL value
- timers in the past
- moving counters ahead and behind pending timers
- reprograming timers
- timers fired multiple times
- masking/unmasking using the timer control mask
These are intentionally unusual scenarios to stress compliance with
the arm architecture.
Co-developed-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
Signed-off-by: Colton Lewis <coltonlewis@xxxxxxxxxx>
---
tools/testing/selftests/kvm/Makefile | 1 +
.../kvm/aarch64/arch_timer_edge_cases.c | 1104 +++++++++++++++++
.../kvm/include/aarch64/arch_timer.h | 18 +-
3 files changed, 1122 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/kvm/aarch64/arch_timer_edge_cases.c
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index a3bb36fb3cfc..e940b7c6b818 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -141,6 +141,7 @@ TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test
TEST_GEN_PROGS_aarch64 += aarch64/aarch32_id_regs
TEST_GEN_PROGS_aarch64 += aarch64/arch_timer
+TEST_GEN_PROGS_aarch64 += aarch64/arch_timer_edge_cases
TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions
TEST_GEN_PROGS_aarch64 += aarch64/hypercalls
TEST_GEN_PROGS_aarch64 += aarch64/page_fault_test
diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer_edge_cases.c b/tools/testing/selftests/kvm/aarch64/arch_timer_edge_cases.c
new file mode 100644
index 000000000000..7173c5c7b211
--- /dev/null
+++ b/tools/testing/selftests/kvm/aarch64/arch_timer_edge_cases.c
@@ -0,0 +1,1104 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * arch_timer_edge_cases.c - Tests the aarch64 timer IRQ functionality.
+ *
+ * The test validates some edge cases related to the arch-timer:
+ * - timers above the max TVAL value.
+ * - timers in the past
+ * - moving counters ahead and behind pending timers.
+ * - reprograming timers.
+ * - timers fired multiple times.
+ * - masking/unmasking using the timer control mask.
+ *
+ * Copyright (c) 2021, Google LLC.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <pthread.h>
+#include <linux/kvm.h>
+#include <linux/atomic.h>
+#include <linux/bitmap.h>
+#include <linux/sizes.h>
+#include <sched.h>
+#include <sys/sysinfo.h>
+
+#include "kvm_util.h"
+#include "processor.h"
+#include "delay.h"
+#include "arch_timer.h"
+#include "gic.h"
+#include "vgic.h"
+
+#define msecs_to_usecs(msec) ((msec) * 1000LL)
+
+#define CVAL_MAX ~0ULL
+/* tval is a signed 32-bit int. */
+#define TVAL_MAX INT_MAX
+#define TVAL_MIN INT_MIN
+
+/* After how much time we say there is no IRQ. */
+#define TIMEOUT_NO_IRQ_US msecs_to_usecs(50)
+
+#define TEST_MARGIN_US 1000ULL
+
+/* A nice counter value to use as the starting one for most tests. */
+#define DEF_CNT (CVAL_MAX / 2)
+
+/* Number of runs. */
+#define NR_TEST_ITERS_DEF 5
+
+/* Default wait test time in ms. */
+#define WAIT_TEST_MS 10
+
+/* Default "long" wait test time in ms. */
+#define LONG_WAIT_TEST_MS 100
+
+/* Shared with IRQ handler. */
+struct test_vcpu_shared_data {
+ atomic_t handled;
+ atomic_t spurious;
+} shared_data;
+
+struct test_args {
+ /* Virtual or physical timer and counter tests. */
+ enum arch_timer timer;
+ /* Delay used for most timer tests. */
+ uint64_t wait_ms;
+ /* Delay used in the test_long_timer_delays test. */
+ uint64_t long_wait_ms;
+ /* Number of iterations. */
+ int iterations;
+ /* Whether to test the physical timer. */
+ bool test_physical;
+ /* Whether to test the virtual timer. */
+ bool test_virtual;
+};
+
+struct test_args test_args = {
+ .wait_ms = WAIT_TEST_MS,
+ .long_wait_ms = LONG_WAIT_TEST_MS,
+ .iterations = NR_TEST_ITERS_DEF,
+ .test_physical = true,
+ .test_virtual = true,
+};
+
+static int vtimer_irq, ptimer_irq;
+
+enum sync_cmd {
+ SET_REG_KVM_REG_ARM_TIMER_CNT = 100001,
+ USERSPACE_USLEEP,
+ USERSPACE_SCHED_YIELD,
+ USERSPACE_MIGRATE_SELF,
+ NO_USERSPACE_CMD,
+};
+
+typedef void (*sleep_method_t)(enum arch_timer timer, uint64_t usec);
+
+static void sleep_poll(enum arch_timer timer, uint64_t usec);
+static void sleep_sched_poll(enum arch_timer timer, uint64_t usec);
+static void sleep_in_userspace(enum arch_timer timer, uint64_t usec);
+static void sleep_migrate(enum arch_timer timer, uint64_t usec);
+
+sleep_method_t sleep_method[] = {
+ sleep_poll,
+ sleep_sched_poll,
+ sleep_migrate,
+ sleep_in_userspace,
+};
+
+typedef void (*wfi_method_t)(void);
+
+static void wait_for_non_spurious_irq(void);
+static void wait_poll_for_irq(void);
+static void wait_sched_poll_for_irq(void);
+static void wait_migrate_poll_for_irq(void);
+
+wfi_method_t wfi_method[] = {
+ wait_for_non_spurious_irq,
+ wait_poll_for_irq,
+ wait_sched_poll_for_irq,
+ wait_migrate_poll_for_irq,
+};
+
+#define for_each_wfi_method(i) \
+ for ((i) = 0; (i) < ARRAY_SIZE(wfi_method); (i)++)
+
+#define for_each_sleep_method(i) \
+ for ((i) = 0; (i) < ARRAY_SIZE(sleep_method); (i)++)
+
+enum timer_view {
+ TIMER_CVAL = 1,
+ TIMER_TVAL,
+};
+
+#define ASSERT_IRQS_HANDLED(_nr, _args...) do { \
+ int _h = atomic_read(&shared_data.handled); \
+ __GUEST_ASSERT(_h == (_nr), "Handled %d IRQS but expected %d", _h, _nr, ##_args); \
+ } while (0)
+
+#define GUEST_SYNC_CLOCK(__cmd, __val) \
+ GUEST_SYNC_ARGS(__cmd, __val, 0, 0, 0)
+
+#define USERSPACE_CMD(__cmd) \
+ GUEST_SYNC_ARGS(__cmd, 0, 0, 0, 0)
+
+#define USERSPACE_SCHEDULE() \
+ USERSPACE_CMD(USERSPACE_SCHED_YIELD)
+
+#define USERSPACE_MIGRATE_VCPU() \
+ USERSPACE_CMD(USERSPACE_MIGRATE_SELF)
+
+#define SLEEP_IN_USERSPACE(__usecs) \
+ GUEST_SYNC_ARGS(USERSPACE_USLEEP, (__usecs), 0, 0, 0)
+
+#define IAR_SPURIOUS 1023
+
+static void set_counter(enum arch_timer timer, uint64_t counter)
+{
+ GUEST_SYNC_ARGS(SET_REG_KVM_REG_ARM_TIMER_CNT, counter, timer, 0, 0);
+}
+
+static uint32_t next_pcpu(void)
+{
+ uint32_t max = get_nprocs();
+ uint32_t cur = sched_getcpu();
+ uint32_t next = cur;
+ cpu_set_t cpuset;
+
+ TEST_ASSERT(max > 1, "Need at least two physical cpus");
+
+ sched_getaffinity(getpid(), sizeof(cpuset), &cpuset);
+
+ do {
+ next = (next + 1) % CPU_SETSIZE;
+ } while (!CPU_ISSET(next, &cpuset));
+
+ return next;
+}
+
+static void guest_irq_handler(struct ex_regs *regs)
+{
+ unsigned int intid = gic_get_and_ack_irq();
+ enum arch_timer timer;
+ uint64_t cnt, cval;
+ uint32_t ctl;
+ bool timer_condition, istatus;
+
+ if (intid == IAR_SPURIOUS) {
+ atomic_inc(&shared_data.spurious);
+ goto out;
+ }
+
+ if (intid == ptimer_irq)
+ timer = PHYSICAL;
+ else if (intid == vtimer_irq)
+ timer = VIRTUAL;
+ else
+ goto out;
+
+ ctl = timer_get_ctl(timer);
+ cval = timer_get_cval(timer);
+ cnt = timer_get_cntct(timer);
+ timer_condition = cnt >= cval;
+ istatus = (ctl & CTL_ISTATUS) && (ctl & CTL_ENABLE);
+ GUEST_ASSERT_EQ(timer_condition, istatus);
+
+ /* Disable and mask the timer. */
+ timer_set_ctl(timer, CTL_IMASK);
+
+ atomic_inc(&shared_data.handled);
+
+out:
+ gic_set_eoi(intid);
+}
+
+static void set_cval_irq(enum arch_timer timer, uint64_t cval_cycles,
+ uint32_t ctl)
+{
+ atomic_set(&shared_data.handled, 0);
+ atomic_set(&shared_data.spurious, 0);
+ timer_set_cval(timer, cval_cycles);
+ timer_set_ctl(timer, ctl);
+}
+
+static void set_tval_irq(enum arch_timer timer, uint64_t tval_cycles,
+ uint32_t ctl)
+{
+ atomic_set(&shared_data.handled, 0);
+ atomic_set(&shared_data.spurious, 0);
+ timer_set_tval(timer, tval_cycles);
+ timer_set_ctl(timer, ctl);
+}
+
+static void set_xval_irq(enum arch_timer timer, uint64_t xval, uint32_t ctl,
+ enum timer_view tv)
+{
+ switch (tv) {
+ case TIMER_CVAL:
+ set_cval_irq(timer, xval, ctl);
+ break;
+ case TIMER_TVAL:
+ set_tval_irq(timer, xval, ctl);
+ break;
+ default:
+ GUEST_FAIL("Could not get timer %d", timer);
+ }
+}
+
+/*
+ * Should be called with IRQs masked.
+ *
+ * Note that this can theoretically hang forever, so we rely on having
+ * a timeout mechanism in the "runner", like:
+ * tools/testing/selftests/kselftest/runner.sh.
+ */
+static void wait_for_non_spurious_irq(void)
+{
+ int h;
+
+ for (h = atomic_read(&shared_data.handled); h == atomic_read(&shared_data.handled);) {
+ gic_wfi();
+ local_irq_enable();
+ isb();
+ /* handle IRQ */
+ local_irq_disable();
+ }
+}
+
+/*
+ * Wait for an non-spurious IRQ by polling in the guest (userspace=0) or in
+ * userspace (e.g., userspace=1 and userspace_cmd=USERSPACE_SCHED_YIELD).
+ *
+ * Should be called with IRQs masked. Not really needed like the wfi above, but
+ * it should match the others.
+ *
+ * Note that this can theoretically hang forever, so we rely on having
+ * a timeout mechanism in the "runner", like:
+ * tools/testing/selftests/kselftest/runner.sh.
+ */
+static void poll_for_non_spurious_irq(enum sync_cmd userspace_cmd)
+{
+ int h;
+
+ h = atomic_read(&shared_data.handled);
+
+ local_irq_enable();
+ while (h == atomic_read(&shared_data.handled)) {
+ if (userspace_cmd == NO_USERSPACE_CMD)
+ cpu_relax();
+ else
+ USERSPACE_CMD(userspace_cmd);
+ }
+ local_irq_disable();
+}
+
+static void wait_poll_for_irq(void)
+{
+ poll_for_non_spurious_irq(NO_USERSPACE_CMD);
+}
+
+static void wait_sched_poll_for_irq(void)
+{
+ poll_for_non_spurious_irq(USERSPACE_SCHED_YIELD);
+}
+
+static void wait_migrate_poll_for_irq(void)
+{
+ poll_for_non_spurious_irq(USERSPACE_MIGRATE_SELF);
+}
+
+/*
+ * Sleep for usec microseconds by polling in the guest (userspace=0) or in
+ * userspace (e.g., userspace=1 and userspace_cmd=USERSPACE_SCHEDULE).
+ */
+static void guest_poll(enum arch_timer test_timer, uint64_t usec,
+ enum sync_cmd userspace_cmd)
+{
+ uint64_t cycles = usec_to_cycles(usec);
+ /* Whichever timer we are testing with, sleep with the other. */
+ enum arch_timer sleep_timer = 1 - test_timer;
+ uint64_t start = timer_get_cntct(sleep_timer);
+
+ while ((timer_get_cntct(sleep_timer) - start) < cycles) {
+ if (userspace_cmd == NO_USERSPACE_CMD)
+ cpu_relax();
+ else
+ USERSPACE_CMD(userspace_cmd);
+ }
+}
+
+static void sleep_poll(enum arch_timer timer, uint64_t usec)
+{
+ guest_poll(timer, usec, NO_USERSPACE_CMD);
+}
+
+static void sleep_sched_poll(enum arch_timer timer, uint64_t usec)
+{
+ guest_poll(timer, usec, USERSPACE_SCHED_YIELD);
+}
+
+static void sleep_migrate(enum arch_timer timer, uint64_t usec)
+{
+ guest_poll(timer, usec, USERSPACE_MIGRATE_SELF);
+}
+
+static void sleep_in_userspace(enum arch_timer timer, uint64_t usec)
+{
+ SLEEP_IN_USERSPACE(usec);
+}
+
+/*
+ * Reset the timer state to some nice values like the counter not being close
+ * to the edge, and the control register masked and disabled.
+ */
+static void reset_timer_state(enum arch_timer timer, uint64_t cnt)
+{
+ set_counter(timer, cnt);
+ timer_set_ctl(timer, CTL_IMASK);
+}
+
+static void test_timer_xval(enum arch_timer timer, uint64_t xval,
+ enum timer_view tv, wfi_method_t wm, bool reset_state,
+ uint64_t reset_cnt)
+{
+ local_irq_disable();
+
+ if (reset_state)
+ reset_timer_state(timer, reset_cnt);
+
+ set_xval_irq(timer, xval, CTL_ENABLE, tv);
+ wm();
+
+ ASSERT_IRQS_HANDLED(1, tv, wm);
+ local_irq_enable();
+}
+
+/*
+ * The test_timer_* functions will program the timer, wait for it, and assert
+ * the firing of the correct IRQ.
+ *
+ * These functions don't have a timeout and return as soon as they receive an
+ * IRQ. They can hang (forever), so we rely on having a timeout mechanism in
+ * the "runner", like: tools/testing/selftests/kselftest/runner.sh.
+ */
+
+static void test_timer_cval(enum arch_timer timer, uint64_t cval,
+ wfi_method_t wm, bool reset_state,
+ uint64_t reset_cnt)
+{
+ test_timer_xval(timer, cval, TIMER_CVAL, wm, reset_state, reset_cnt);
+}
+
+static void test_timer_tval(enum arch_timer timer, int32_t tval,
+ wfi_method_t wm, bool reset_state,
+ uint64_t reset_cnt)
+{
+ test_timer_xval(timer, (uint64_t) tval, TIMER_TVAL, wm, reset_state,
+ reset_cnt);
+}
+
+static void test_xval_check_no_irq(enum arch_timer timer, uint64_t xval,
+ uint64_t usec, enum timer_view timer_view,
+ sleep_method_t guest_sleep)
+{
+ local_irq_disable();
+
+ set_xval_irq(timer, xval, CTL_ENABLE | CTL_IMASK, timer_view);
+ guest_sleep(timer, usec);
+
+ local_irq_enable();
+ isb();
+
+ /* Assume success (no IRQ) after waiting usec microseconds */
+ ASSERT_IRQS_HANDLED(0);
+}
+
+static void test_cval_no_irq(enum arch_timer timer, uint64_t cval,
+ uint64_t usec, sleep_method_t wm)
+{
+ test_xval_check_no_irq(timer, cval, usec, TIMER_CVAL, wm);
+}
+
+static void test_tval_no_irq(enum arch_timer timer, int32_t tval, uint64_t usec,
+ sleep_method_t wm)
+{
+ /* tval will be cast to an int32_t in test_xval_check_no_irq */
+ test_xval_check_no_irq(timer, (uint64_t) tval, usec, TIMER_TVAL, wm);
+}
+
+/* Test masking/unmasking a timer using the timer mask (not the IRQ mask). */
+static void test_timer_control_mask_then_unmask(enum arch_timer timer)
+{
+ reset_timer_state(timer, DEF_CNT);
+ set_tval_irq(timer, -1, CTL_ENABLE | CTL_IMASK);
+
+ /* No IRQs because the timer is still masked. */
+ ASSERT_IRQS_HANDLED(0);
+
+ /* Unmask the timer, and then get an IRQ. */
+ local_irq_disable();
+ timer_set_ctl(timer, CTL_ENABLE);
+ wait_for_non_spurious_irq();
+
+ ASSERT_IRQS_HANDLED(1);
+ local_irq_enable();
+}
+
+/* Check that timer control masks actually mask a timer being fired. */
+static void test_timer_control_masks(enum arch_timer timer)
+{
+ reset_timer_state(timer, DEF_CNT);
+
+ /* Local IRQs are not masked at this point. */
+
+ set_tval_irq(timer, -1, CTL_ENABLE | CTL_IMASK);
+
+ /* Assume no IRQ after waiting TIMEOUT_NO_IRQ_US microseconds */
+ sleep_poll(timer, TIMEOUT_NO_IRQ_US);
+
+ ASSERT_IRQS_HANDLED(0);
+ timer_set_ctl(timer, CTL_IMASK);
+}
+
+static void test_fire_a_timer_multiple_times(enum arch_timer timer,
+ wfi_method_t wm, int num)
+{
+ int i;
+
+ local_irq_disable();
+ reset_timer_state(timer, DEF_CNT);
+
+ set_tval_irq(timer, 0, CTL_ENABLE);
+
+ for (i = 1; i <= num; i++) {
+ wm();
+
+ /* The IRQ handler masked and disabled the timer.
+ * Enable and unmmask it again.
+ */
+ timer_set_ctl(timer, CTL_ENABLE);
+
+ ASSERT_IRQS_HANDLED(i);
+ }
+
+ local_irq_enable();
+}
+
+static void test_timers_fired_multiple_times(enum arch_timer timer)
+{
+ int i;
+
+ for_each_wfi_method(i)
+ test_fire_a_timer_multiple_times(timer, wfi_method[i], 10);
+}
+
+/*
+ * Set a timer for tval=d_1_ms then reprogram it to tval=d_2_ms. Check that we
+ * get the timer fired. There is no timeout for the wait: we use the wfi
+ * instruction.
+ */
+static void test_reprogramming_timer(enum arch_timer timer, wfi_method_t wm,
+ int32_t d_1_ms, int32_t d_2_ms)
+{
+ local_irq_disable();
+ reset_timer_state(timer, DEF_CNT);
+
+ /* Program the timer to DEF_CNT + d_1_ms. */
+ set_tval_irq(timer, msec_to_cycles(d_1_ms), CTL_ENABLE);
+
+ /* Reprogram the timer to DEF_CNT + d_2_ms. */
+ timer_set_tval(timer, msec_to_cycles(d_2_ms));
+
+ wm();
+
+ /* The IRQ should arrive at DEF_CNT + d_2_ms (or after). */
+ GUEST_ASSERT(timer_get_cntct(timer) >=
+ DEF_CNT + msec_to_cycles(d_2_ms));
+
+ local_irq_enable();
+ ASSERT_IRQS_HANDLED(1, wm);
+};
+
+/*
+ * Set a timer for tval=d_1_ms then reprogram it to tval=d_2_ms. Check
+ * that we get the timer fired in d_2_ms.
+ */
+static void test_reprogramming_timer_with_timeout(enum arch_timer timer,
+ sleep_method_t guest_sleep,
+ int32_t d_1_ms,
+ int32_t d_2_ms)
+{
+ local_irq_disable();
+ reset_timer_state(timer, DEF_CNT);
+
+ set_tval_irq(timer, msec_to_cycles(d_1_ms), CTL_ENABLE);
+
+ /* Reprogram the timer. */
+ timer_set_tval(timer, msec_to_cycles(d_2_ms));
+
+ guest_sleep(timer, msecs_to_usecs(d_2_ms) + TEST_MARGIN_US);
+
+ local_irq_enable();
+ isb();
+ ASSERT_IRQS_HANDLED(1);
+};
+
+static void test_reprogram_timers(enum arch_timer timer)
+{
+ int i;
+ uint64_t base_wait = test_args.wait_ms;
+
+ for_each_wfi_method(i) {
+ test_reprogramming_timer(timer, wfi_method[i], 2 * base_wait,
+ base_wait);
+ test_reprogramming_timer(timer, wfi_method[i], base_wait,
+ 2 * base_wait);
+ }
+
+ for_each_sleep_method(i) {
+ test_reprogramming_timer_with_timeout(timer, sleep_method[i],
+ 2 * base_wait, base_wait);
+ test_reprogramming_timer_with_timeout(timer, sleep_method[i],
+ base_wait, 2 * base_wait);
+ }
+}
+
+static void test_basic_functionality(enum arch_timer timer)
+{
+ int32_t tval = (int32_t) msec_to_cycles(test_args.wait_ms);
+ uint64_t cval;
+ int i;
+
+ for_each_wfi_method(i) {
+ wfi_method_t wm = wfi_method[i];
+
+ cval = DEF_CNT + msec_to_cycles(test_args.wait_ms);
+
+ test_timer_cval(timer, cval, wm, true, DEF_CNT);
+ test_timer_tval(timer, tval, wm, true, DEF_CNT);
+ }
+}
+
+/*
+ * This test checks basic timer behavior without actually firing timers, things
+ * like: the relationship between cval and tval, tval down-counting.
+ */
+static void timers_sanity_checks(enum arch_timer timer, bool use_sched)
+{
+ reset_timer_state(timer, DEF_CNT);
+
+ local_irq_disable();
+
+ /* cval in the past */
+ timer_set_cval(timer,
+ timer_get_cntct(timer) -
+ msec_to_cycles(test_args.wait_ms));
+ if (use_sched)
+ USERSPACE_MIGRATE_VCPU();
+ GUEST_ASSERT(timer_get_tval(timer) < 0);
+
+ /* tval in the past */
+ timer_set_tval(timer, -1);
+ if (use_sched)
+ USERSPACE_MIGRATE_VCPU();
+ GUEST_ASSERT(timer_get_cval(timer) < timer_get_cntct(timer));
+
+ /* tval larger than TVAL_MAX. */
+ timer_set_cval(timer,
+ timer_get_cntct(timer) + TVAL_MAX +
+ msec_to_cycles(test_args.wait_ms));
+ if (use_sched)
+ USERSPACE_MIGRATE_VCPU();
+ GUEST_ASSERT(timer_get_tval(timer) <= 0);
+
+ /*
+ * tval larger than 2 * TVAL_MAX.
+ * Twice the TVAL_MAX completely loops around the TVAL.
+ */
+ timer_set_cval(timer,
+ timer_get_cntct(timer) + 2ULL * TVAL_MAX +
+ msec_to_cycles(test_args.wait_ms));
+ if (use_sched)
+ USERSPACE_MIGRATE_VCPU();
+ GUEST_ASSERT(timer_get_tval(timer) <=
+ msec_to_cycles(test_args.wait_ms));
+
+ /* negative tval that rollovers from 0. */
+ set_counter(timer, msec_to_cycles(1));
+ timer_set_tval(timer, -1 * msec_to_cycles(test_args.wait_ms));
+ if (use_sched)
+ USERSPACE_MIGRATE_VCPU();
+ GUEST_ASSERT(timer_get_cval(timer) >= (CVAL_MAX - msec_to_cycles(9)));
+
+ /* tval should keep down-counting from 0 to -1. */
+ timer_set_tval(timer, 0);
+ sleep_poll(timer, 1);
+ GUEST_ASSERT(timer_get_tval(timer) < 0);
+
+ local_irq_enable();
+
+ /* Mask and disable any pending timer. */
+ timer_set_ctl(timer, CTL_IMASK);
+}
+
+static void test_timers_sanity_checks(enum arch_timer timer)
+{
+ timers_sanity_checks(timer, false);
+ /* Check how KVM saves/restores these edge-case values. */
+ timers_sanity_checks(timer, true);
+}
+
+static void test_set_cnt_after_tval_max(enum arch_timer timer, wfi_method_t wm)
+{
+ local_irq_disable();
+ reset_timer_state(timer, DEF_CNT);
+
+ set_cval_irq(timer,
+ (uint64_t) TVAL_MAX +
+ msec_to_cycles(test_args.wait_ms) / 2, CTL_ENABLE);
+
+ set_counter(timer, TVAL_MAX);
+ wm();
+
+ ASSERT_IRQS_HANDLED(1, wm);
+ local_irq_enable();
+}
+
+/* Test timers set for: cval = now + TVAL_MAX + wait_ms / 2*/
+static void test_timers_above_tval_max(enum arch_timer timer)
+{
+ uint64_t cval;
+ int i;
+
+ /*
+ * Test that the system is not implementing cval in terms of
+ * tval. If that was the case, setting a cval to "cval = now
+ * + TVAL_MAX + wait_ms" would wrap to "cval = now +
+ * wait_ms / 2", and the timer would fire immediately. Test that it
+ * doesn't.
+ */
+ for_each_sleep_method(i) {
+ reset_timer_state(timer, DEF_CNT);
+ cval =
+ timer_get_cntct(timer) + TVAL_MAX +
+ msec_to_cycles(test_args.wait_ms) / 2;
+ test_cval_no_irq(timer, cval,
+ msecs_to_usecs(test_args.wait_ms) / 2 +
+ TEST_MARGIN_US, sleep_method[i]);
+ }
+
+ for_each_wfi_method(i) {
+ /* Get the IRQ by moving the counter forward. */
+ test_set_cnt_after_tval_max(timer, wfi_method[i]);
+ }
+}
+
+/*
+ * Template function to be used by the test_move_counter_ahead_* tests. It
+ * sets the counter to cnt_1, the [c|t]val, the counter to cnt_2, and
+ * then waits for an IRQ.
+ */
+static void test_set_cnt_after_xval(enum arch_timer timer, uint64_t cnt_1,
+ uint64_t xval, uint64_t cnt_2,
+ wfi_method_t wm, enum timer_view tv)
+{
+ local_irq_disable();
+
+ set_counter(timer, cnt_1);
+ timer_set_ctl(timer, CTL_IMASK);
+
+ set_xval_irq(timer, xval, CTL_ENABLE, tv);
+ set_counter(timer, cnt_2);
+ wm();
+
+ ASSERT_IRQS_HANDLED(1);
+ local_irq_enable();
+}
+
+/*
+ * Template function to be used by the test_move_counter_ahead_* tests. It
+ * sets the counter to cnt_1, the [c|t]val, the counter to cnt_2, and
+ * then waits for an IRQ.
+ */
+static void test_set_cnt_after_xval_no_irq(enum arch_timer timer,
+ uint64_t cnt_1, uint64_t xval,
+ uint64_t cnt_2,
+ sleep_method_t guest_sleep,
+ enum timer_view tv)
+{
+ local_irq_disable();
+
+ set_counter(timer, cnt_1);
+ timer_set_ctl(timer, CTL_IMASK);
+
+ set_xval_irq(timer, xval, CTL_ENABLE, tv);
+ set_counter(timer, cnt_2);
+ guest_sleep(timer, TIMEOUT_NO_IRQ_US);
+
+ local_irq_enable();
+ isb();
+
+ /* Assume no IRQ after waiting TIMEOUT_NO_IRQ_US microseconds */
+ ASSERT_IRQS_HANDLED(0);
+ timer_set_ctl(timer, CTL_IMASK);
+}
+
+static void test_set_cnt_after_tval(enum arch_timer timer, uint64_t cnt_1,
+ int32_t tval, uint64_t cnt_2,
+ wfi_method_t wm)
+{
+ test_set_cnt_after_xval(timer, cnt_1, tval, cnt_2, wm, TIMER_TVAL);
+}
+
+static void test_set_cnt_after_cval(enum arch_timer timer, uint64_t cnt_1,
+ uint64_t cval, uint64_t cnt_2,
+ wfi_method_t wm)
+{
+ test_set_cnt_after_xval(timer, cnt_1, cval, cnt_2, wm, TIMER_CVAL);
+}
+
+static void test_set_cnt_after_tval_no_irq(enum arch_timer timer,
+ uint64_t cnt_1, int32_t tval,
+ uint64_t cnt_2, sleep_method_t wm)
+{
+ test_set_cnt_after_xval_no_irq(timer, cnt_1, tval, cnt_2, wm,
+ TIMER_TVAL);
+}
+
+static void test_set_cnt_after_cval_no_irq(enum arch_timer timer,
+ uint64_t cnt_1, uint64_t cval,
+ uint64_t cnt_2, sleep_method_t wm)
+{
+ test_set_cnt_after_xval_no_irq(timer, cnt_1, cval, cnt_2, wm,
+ TIMER_CVAL);
+}
+
+/* Set a timer and then move the counter ahead of it. */
+static void test_move_counters_ahead_of_timers(enum arch_timer timer)
+{
+ int i;
+ int32_t tval;
+
+ for_each_wfi_method(i) {
+ wfi_method_t wm = wfi_method[i];
+
+ test_set_cnt_after_cval(timer, 0, DEF_CNT, DEF_CNT + 1, wm);
+ test_set_cnt_after_cval(timer, CVAL_MAX, 1, 2, wm);
+
+ /* Move counter ahead of negative tval. */
+ test_set_cnt_after_tval(timer, 0, -1, DEF_CNT + 1, wm);
+ test_set_cnt_after_tval(timer, 0, -1, TVAL_MAX, wm);
+ tval = TVAL_MAX;
+ test_set_cnt_after_tval(timer, 0, tval, (uint64_t) tval + 1,
+ wm);
+ }
+
+ for_each_sleep_method(i) {
+ sleep_method_t sm = sleep_method[i];
+
+ test_set_cnt_after_cval_no_irq(timer, 0, DEF_CNT, CVAL_MAX, sm);
+ }
+}
+
+/*
+ * Program a timer, mask it, and then change the tval or counter to cancel it.
+ * Unmask it and check that nothing fires.
+ */
+static void test_move_counters_behind_timers(enum arch_timer timer)
+{
+ int i;
+
+ for_each_sleep_method(i) {
+ sleep_method_t sm = sleep_method[i];
+
+ test_set_cnt_after_cval_no_irq(timer, DEF_CNT, DEF_CNT - 1, 0,
+ sm);
+ test_set_cnt_after_tval_no_irq(timer, DEF_CNT, -1, 0, sm);
+ }
+}
+
+static void test_timers_in_the_past(enum arch_timer timer)
+{
+ int32_t tval = -1 * (int32_t) msec_to_cycles(test_args.wait_ms);
+ uint64_t cval;
+ int i;
+
+ for_each_wfi_method(i) {
+ wfi_method_t wm = wfi_method[i];
+
+ /* set a timer wait_ms the past. */
+ cval = DEF_CNT - msec_to_cycles(test_args.wait_ms);
+ test_timer_cval(timer, cval, wm, true, DEF_CNT);
+ test_timer_tval(timer, tval, wm, true, DEF_CNT);
+
+ /* Set a timer to counter=0 (in the past) */
+ test_timer_cval(timer, 0, wm, true, DEF_CNT);
+
+ /* Set a time for tval=0 (now) */
+ test_timer_tval(timer, 0, wm, true, DEF_CNT);
+
+ /* Set a timer to as far in the past as possible */
+ test_timer_tval(timer, TVAL_MIN, wm, true, DEF_CNT);
+ }
+
+ /*
+ * Set the counter to wait_ms, and a tval to -wait_ms. There should be no
+ * timer as that tval means cval=CVAL_MAX-wait_ms.
+ */
+ for_each_sleep_method(i) {
+ sleep_method_t sm = sleep_method[i];
+
+ set_counter(timer, msec_to_cycles(test_args.wait_ms));
+ test_tval_no_irq(timer, tval, TIMEOUT_NO_IRQ_US, sm);
+ }
+}
+
+static void test_long_timer_delays(enum arch_timer timer)
+{
+ int32_t tval = (int32_t) msec_to_cycles(test_args.long_wait_ms);
+ uint64_t cval;
+ int i;
+
+ for_each_wfi_method(i) {
+ wfi_method_t wm = wfi_method[i];
+
+ cval = DEF_CNT + msec_to_cycles(test_args.long_wait_ms);
+ test_timer_cval(timer, cval, wm, true, DEF_CNT);
+ test_timer_tval(timer, tval, wm, true, DEF_CNT);
+ }
+}
+
+static void guest_run_iteration(enum arch_timer timer)
+{
+ test_basic_functionality(timer);
+ test_timers_sanity_checks(timer);
+
+ test_timers_above_tval_max(timer);
+ test_timers_in_the_past(timer);
+
+ test_move_counters_ahead_of_timers(timer);
+ test_move_counters_behind_timers(timer);
+ test_reprogram_timers(timer);
+
+ test_timers_fired_multiple_times(timer);
+
+ test_timer_control_mask_then_unmask(timer);
+ test_timer_control_masks(timer);
+}
+
+static void guest_code(enum arch_timer timer)
+{
+ int i;
+
+ local_irq_disable();
+
+ gic_init(GIC_V3, 1);
+
+ timer_set_ctl(VIRTUAL, CTL_IMASK);
+ timer_set_ctl(PHYSICAL, CTL_IMASK);
+
+ gic_irq_enable(vtimer_irq);
+ gic_irq_enable(ptimer_irq);
+ local_irq_enable();
+
+ for (i = 0; i < test_args.iterations; i++) {
+ GUEST_SYNC(i);
+ guest_run_iteration(timer);
+ }
+
+ test_long_timer_delays(timer);
+ GUEST_DONE();
+}
+
+static void migrate_self(uint32_t new_pcpu)
+{
+ int ret;
+ cpu_set_t cpuset;
+ pthread_t thread;
+
+ thread = pthread_self();
+
+ CPU_ZERO(&cpuset);
+ CPU_SET(new_pcpu, &cpuset);
+
+ pr_debug("Migrating from %u to %u\n", sched_getcpu(), new_pcpu);
+
+ ret = pthread_setaffinity_np(thread, sizeof(cpuset), &cpuset);
+
+ TEST_ASSERT(ret == 0, "Failed to migrate to pCPU: %u; ret: %d\n",
+ new_pcpu, ret);
+}
+
+static void kvm_set_cntxct(struct kvm_vcpu *vcpu, uint64_t cnt,
+ enum arch_timer timer)
+{
+ if (timer == PHYSICAL)
+ vcpu_set_reg(vcpu, KVM_REG_ARM_PTIMER_CNT, cnt);
+ else
+ vcpu_set_reg(vcpu, KVM_REG_ARM_TIMER_CNT, cnt);
+}
+
+static void handle_sync(struct kvm_vcpu *vcpu, struct ucall *uc)
+{
+ enum sync_cmd cmd = uc->args[1];
+ uint64_t val = uc->args[2];
+ enum arch_timer timer = uc->args[3];
+
+ switch (cmd) {
+ case SET_REG_KVM_REG_ARM_TIMER_CNT:
+ kvm_set_cntxct(vcpu, val, timer);
+ break;
+ case USERSPACE_USLEEP:
+ usleep(val);
+ break;
+ case USERSPACE_SCHED_YIELD:
+ sched_yield();
+ break;
+ case USERSPACE_MIGRATE_SELF:
+ migrate_self(next_pcpu());
+ break;
+ default:
+ break;
+ }
+}
+
+static void test_run(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
+{
+ struct ucall uc;
+
+ while (true) {
+ vcpu_run(vcpu);
+ switch (get_ucall(vcpu, &uc)) {
+ case UCALL_SYNC:
+ handle_sync(vcpu, &uc);
+ break;
+ case UCALL_DONE:
+ goto out;
+ case UCALL_ABORT:
+ REPORT_GUEST_ASSERT(uc);
+ goto out;
+ default:
+ TEST_FAIL("Unexpected guest exit\n");
+ }
+ }
+
+ out:
+ return;
+}
+
+static void test_init_timer_irq(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
+{
+ vcpu_device_attr_get(vcpu, KVM_ARM_VCPU_TIMER_CTRL,
+ KVM_ARM_VCPU_TIMER_IRQ_PTIMER, &ptimer_irq);
+ vcpu_device_attr_get(vcpu, KVM_ARM_VCPU_TIMER_CTRL,
+ KVM_ARM_VCPU_TIMER_IRQ_VTIMER, &vtimer_irq);
+
+ sync_global_to_guest(vm, ptimer_irq);
+ sync_global_to_guest(vm, vtimer_irq);
+
+ pr_debug("ptimer_irq: %d; vtimer_irq: %d\n", ptimer_irq, vtimer_irq);
+}
+
+static void test_vm_create(struct kvm_vm **vm, struct kvm_vcpu **vcpu,
+ enum arch_timer timer)
+{
+ *vm = vm_create_with_one_vcpu(vcpu, guest_code);
+ TEST_ASSERT(*vm, "Failed to create the test VM\n");
+
+ vm_init_descriptor_tables(*vm);
+ vm_install_exception_handler(*vm, VECTOR_IRQ_CURRENT,
+ guest_irq_handler);
+
+ vcpu_init_descriptor_tables(*vcpu);
+ vcpu_args_set(*vcpu, 1, timer);
+
+ test_init_timer_irq(*vm, *vcpu);
+ vgic_v3_setup(*vm, 1, 64);
+ sync_global_to_guest(*vm, test_args);
+}
+
+static void test_print_help(char *name)
+{
+ pr_info("Usage: %s [-h] [-b] [-i iterations] [-l long_wait_ms] [-p] [-v]\n"
+ , name);
+ pr_info("\t-i: Number of iterations (default: %u)\n",
+ NR_TEST_ITERS_DEF);
+ pr_info("\t-b: Test both physical and virtual timers (default: true)\n");
+ pr_info("\t-l: Delta (in ms) used for long wait time test (default: %u)\n",
+ LONG_WAIT_TEST_MS);
+ pr_info("\t-l: Delta (in ms) used for wait times (default: %u)\n",
+ WAIT_TEST_MS);
+ pr_info("\t-p: Test physical timer (default: true)\n");
+ pr_info("\t-v: Test virtual timer (default: true)\n");
+ pr_info("\t-h: Print this help message\n");
+}
+
+static bool parse_args(int argc, char *argv[])
+{
+ int opt;
+
+ while ((opt = getopt(argc, argv, "bhi:l:pvw:")) != -1) {
+ switch (opt) {
+ case 'b':
+ test_args.test_physical = true;
+ test_args.test_virtual = true;
+ break;
+ case 'i':
+ test_args.iterations =
+ atoi_positive("Number of iterations", optarg);
+ break;
+ case 'l':
+ test_args.long_wait_ms =
+ atoi_positive("Long wait time", optarg);
+ break;
+ case 'p':
+ test_args.test_physical = true;
+ test_args.test_virtual = false;
+ break;
+ case 'v':
+ test_args.test_virtual = true;
+ test_args.test_physical = false;
+ break;
+ case 'w':
+ test_args.wait_ms = atoi_positive("Wait time", optarg);
+ break;
+ case 'h':
+ default:
+ goto err;
+ }
+ }
+
+ return true;
+
+ err:
+ test_print_help(argv[0]);
+ return false;
+}
+
+int main(int argc, char *argv[])
+{
+ struct kvm_vcpu *vcpu;
+ struct kvm_vm *vm;
+
+ /* Tell stdout not to buffer its content */
+ setbuf(stdout, NULL);
+
+ if (!parse_args(argc, argv))
+ exit(KSFT_SKIP);
+
+ if (test_args.test_virtual) {
+ test_vm_create(&vm, &vcpu, VIRTUAL);
+ test_run(vm, vcpu);
+ kvm_vm_free(vm);
+ }
+
+ if (test_args.test_physical) {
+ test_vm_create(&vm, &vcpu, PHYSICAL);
+ test_run(vm, vcpu);
+ kvm_vm_free(vm);
+ }
+
+ return 0;
+}
diff --git a/tools/testing/selftests/kvm/include/aarch64/arch_timer.h b/tools/testing/selftests/kvm/include/aarch64/arch_timer.h
index b3e97525cb55..bf461de34785 100644
--- a/tools/testing/selftests/kvm/include/aarch64/arch_timer.h
+++ b/tools/testing/selftests/kvm/include/aarch64/arch_timer.h
@@ -79,7 +79,7 @@ static inline uint64_t timer_get_cval(enum arch_timer timer)
return 0;
}
-static inline void timer_set_tval(enum arch_timer timer, uint32_t tval)
+static inline void timer_set_tval(enum arch_timer timer, int32_t tval)
{
switch (timer) {
case VIRTUAL:
@@ -95,6 +95,22 @@ static inline void timer_set_tval(enum arch_timer timer, uint32_t tval)
isb();
}
+static inline int32_t timer_get_tval(enum arch_timer timer)
+{
+ isb();
+ switch (timer) {
+ case VIRTUAL:
+ return read_sysreg(cntv_tval_el0);
+ case PHYSICAL:
+ return read_sysreg(cntp_tval_el0);
+ default:
+ GUEST_FAIL("Could not get timer %d\n", timer);
+ }
+
+ /* We should not reach here */
+ return 0;
+}
+
static inline void timer_set_ctl(enum arch_timer timer, uint32_t ctl)
{
switch (timer) {
--
2.42.0.869.gea05f2083d-goog
