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device: 0.874
x86: 0.867
virtual: 0.783
performance: 0.770
ppc: 0.732
files: 0.709
boot: 0.705
risc-v: 0.701
kernel: 0.694
graphic: 0.682
socket: 0.672
register: 0.670
PID: 0.662
vnc: 0.624
network: 0.594
architecture: 0.574
hypervisor: 0.571
peripherals: 0.558
arm: 0.517
VMM: 0.476
semantic: 0.457
debug: 0.436
TCG: 0.434
KVM: 0.401
i386: 0.389
permissions: 0.352
mistranslation: 0.318
assembly: 0.212
user-level: 0.125
ptimer period sporadically too long
Description of problem:
A ptimer in a custom device with a frequency of 10kHz is sporadically called after more than 100,000ns in virtual time have elapsed.
With a icount shift of 4 or 5 this happens almost everytime before the linux guest can even finish booting.
With a shift of 0 this happens very rarely, but it does occur from time to time.
Steps to reproduce:
1. setup a ptimer with a frequency of 10kHz and assert that the time passed between callbacks is exactly 100,000ns
2. run
3. wait for boom
Additional information:
```
// Timer setup
ptimer_transaction_begin(state->timer);
ptimer_set_freq(state->timer, 10000);
ptimer_run(state->timer, 0);
ptimer_transaction_commit(state->timer);
```
```
// timer callback
int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
static int64_t last = 0;
if (last > 0)
{
if (now - last != 100000)
{
fprintf(stderr, "error tick %ld after %ld is incorrect: %ld\n", now, last, now - last);
assert(0);
}
}
last = now;
```
```
error tick 47867503135 after 47867400000 is incorrect: 103135
qemu-system-x86_64: ../...file.c:119: timer_callback: Assertion `0' failed.
```
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