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|
// 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 <pthread.h>
#include <sys/sysinfo.h>
#include "arch_timer.h"
#include "gic.h"
#include "vgic.h"
static const uint64_t CVAL_MAX = ~0ULL;
/* tval is a signed 32-bit int. */
static const int32_t TVAL_MAX = INT32_MAX;
static const int32_t TVAL_MIN = INT32_MIN;
/* After how much time we say there is no IRQ. */
static const uint32_t TIMEOUT_NO_IRQ_US = 50000;
/* A nice counter value to use as the starting one for most tests. */
static const uint64_t DEF_CNT = (CVAL_MAX / 2);
/* Number of runs. */
static const uint32_t NR_TEST_ITERS_DEF = 5;
/* Default wait test time in ms. */
static const uint32_t WAIT_TEST_MS = 10;
/* Default "long" wait test time in ms. */
static const uint32_t 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_COUNTER_VALUE,
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 (*irq_wait_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);
irq_wait_method_t irq_wait_method[] = {
wait_for_non_spurious_irq,
wait_poll_for_irq,
wait_sched_poll_for_irq,
wait_migrate_poll_for_irq,
};
enum timer_view {
TIMER_CVAL,
TIMER_TVAL,
};
static void assert_irqs_handled(uint32_t n)
{
int h = atomic_read(&shared_data.handled);
__GUEST_ASSERT(h == n, "Handled %d IRQS but expected %d", h, n);
}
static void userspace_cmd(uint64_t cmd)
{
GUEST_SYNC_ARGS(cmd, 0, 0, 0, 0);
}
static void userspace_migrate_vcpu(void)
{
userspace_cmd(USERSPACE_MIGRATE_SELF);
}
static void userspace_sleep(uint64_t usecs)
{
GUEST_SYNC_ARGS(USERSPACE_USLEEP, usecs, 0, 0, 0);
}
static void set_counter(enum arch_timer timer, uint64_t counter)
{
GUEST_SYNC_ARGS(SET_COUNTER_VALUE, counter, timer, 0, 0);
}
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_ctl(timer, ctl);
timer_set_tval(timer, tval_cycles);
}
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);
}
}
/*
* 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;
local_irq_disable();
for (h = atomic_read(&shared_data.handled); h == atomic_read(&shared_data.handled);) {
wfi();
local_irq_enable();
isb(); /* handle IRQ */
local_irq_disable();
}
}
/*
* Wait for an non-spurious IRQ by polling in the guest or in
* userspace (e.g. userspace_cmd=USERSPACE_SCHED_YIELD).
*
* 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 usp_cmd)
{
int h;
local_irq_disable();
h = atomic_read(&shared_data.handled);
local_irq_enable();
while (h == atomic_read(&shared_data.handled)) {
if (usp_cmd == NO_USERSPACE_CMD)
cpu_relax();
else
userspace_cmd(usp_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 or in
* userspace (e.g. userspace_cmd=USERSPACE_SCHEDULE).
*/
static void guest_poll(enum arch_timer test_timer, uint64_t usec,
enum sync_cmd usp_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 (usp_cmd == NO_USERSPACE_CMD)
cpu_relax();
else
userspace_cmd(usp_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)
{
userspace_sleep(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, irq_wait_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);
/* This method re-enables IRQs to handle the one we're looking for. */
wm();
assert_irqs_handled(1);
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,
irq_wait_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,
irq_wait_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);
/* Unmask the timer, and then get an IRQ. */
local_irq_disable();
timer_set_ctl(timer, CTL_ENABLE);
/* This method re-enables IRQs to handle the one we're looking for. */
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,
irq_wait_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++) {
/* This method re-enables IRQs to handle the one we're looking for. */
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 (i = 0; i < ARRAY_SIZE(irq_wait_method); i++)
test_fire_a_timer_multiple_times(timer, irq_wait_method[i], 10);
}
/*
* Set a timer for tval=delta_1_ms then reprogram it to
* tval=delta_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, irq_wait_method_t wm,
int32_t delta_1_ms, int32_t delta_2_ms)
{
local_irq_disable();
reset_timer_state(timer, DEF_CNT);
/* Program the timer to DEF_CNT + delta_1_ms. */
set_tval_irq(timer, msec_to_cycles(delta_1_ms), CTL_ENABLE);
/* Reprogram the timer to DEF_CNT + delta_2_ms. */
timer_set_tval(timer, msec_to_cycles(delta_2_ms));
/* This method re-enables IRQs to handle the one we're looking for. */
wm();
/* The IRQ should arrive at DEF_CNT + delta_2_ms (or after). */
GUEST_ASSERT(timer_get_cntct(timer) >=
DEF_CNT + msec_to_cycles(delta_2_ms));
local_irq_enable();
assert_irqs_handled(1);
};
static void test_reprogram_timers(enum arch_timer timer)
{
int i;
uint64_t base_wait = test_args.wait_ms;
for (i = 0; i < ARRAY_SIZE(irq_wait_method); i++) {
/*
* Ensure reprogramming works whether going from a
* longer time to a shorter or vice versa.
*/
test_reprogramming_timer(timer, irq_wait_method[i], 2 * base_wait,
base_wait);
test_reprogramming_timer(timer, irq_wait_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 = DEF_CNT + msec_to_cycles(test_args.wait_ms);
int i;
for (i = 0; i < ARRAY_SIZE(irq_wait_method); i++) {
irq_wait_method_t wm = irq_wait_method[i];
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. This requires programming with
* timer_set_cval instead so the value is expressible
*/
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(test_args.wait_ms)));
/* 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, irq_wait_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);
/* This method re-enables IRQs to handle the one we're looking for. */
wm();
assert_irqs_handled(1);
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", and the timer would fire immediately. Test that it
* doesn't.
*/
for (i = 0; i < ARRAY_SIZE(sleep_method); i++) {
reset_timer_state(timer, DEF_CNT);
cval = timer_get_cntct(timer) + TVAL_MAX +
msec_to_cycles(test_args.wait_ms);
test_cval_no_irq(timer, cval,
msecs_to_usecs(test_args.wait_ms) +
TIMEOUT_NO_IRQ_US, sleep_method[i]);
}
for (i = 0; i < ARRAY_SIZE(irq_wait_method); i++) {
/* Get the IRQ by moving the counter forward. */
test_set_cnt_after_tval_max(timer, irq_wait_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,
irq_wait_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);
/* This method re-enables IRQs to handle the one we're looking for. */
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,
irq_wait_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,
irq_wait_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 (i = 0; i < ARRAY_SIZE(irq_wait_method); i++) {
irq_wait_method_t wm = irq_wait_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 (i = 0; i < ARRAY_SIZE(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 (i = 0; i < ARRAY_SIZE(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 (i = 0; i < ARRAY_SIZE(irq_wait_method); i++) {
irq_wait_method_t wm = irq_wait_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
* IRQ as that tval means cval=CVAL_MAX-wait_ms.
*/
for (i = 0; i < ARRAY_SIZE(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 = DEF_CNT + msec_to_cycles(test_args.long_wait_ms);
int i;
for (i = 0; i < ARRAY_SIZE(irq_wait_method); i++) {
irq_wait_method_t wm = irq_wait_method[i];
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 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(0, sizeof(cpuset), &cpuset);
do {
next = (next + 1) % CPU_SETSIZE;
} while (!CPU_ISSET(next, &cpuset));
return next;
}
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_COUNTER_VALUE:
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;
/* Start on CPU 0 */
migrate_self(0);
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;
}
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