| Message ID | 20250128142152.9889-2-philmd@linaro.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | accel: Only include qdev-realized vCPUs in global &cpus_queue | expand |
On 1/28/25 06:21, Philippe Mathieu-Daudé wrote: > Let vCPUs wait for themselves being ready first, then other ones. > This allows the first thread to starts without the global vcpu > queue (thus &first_cpu) being populated. > > Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> > --- > accel/tcg/tcg-accel-ops-rr.c | 15 ++++++++------- > 1 file changed, 8 insertions(+), 7 deletions(-) > > diff --git a/accel/tcg/tcg-accel-ops-rr.c b/accel/tcg/tcg-accel-ops-rr.c > index 028b385af9a..5ad3d617bce 100644 > --- a/accel/tcg/tcg-accel-ops-rr.c > +++ b/accel/tcg/tcg-accel-ops-rr.c > @@ -197,20 +197,21 @@ static void *rr_cpu_thread_fn(void *arg) > qemu_guest_random_seed_thread_part2(cpu->random_seed); > > /* wait for initial kick-off after machine start */ > - while (first_cpu->stopped) { > - qemu_cond_wait_bql(first_cpu->halt_cond); > + while (cpu->stopped) { > + CPUState *iter_cpu; > + > + qemu_cond_wait_bql(cpu->halt_cond); > > /* process any pending work */ > - CPU_FOREACH(cpu) { > - current_cpu = cpu; > - qemu_wait_io_event_common(cpu); > + CPU_FOREACH(iter_cpu) { > + current_cpu = iter_cpu; > + qemu_wait_io_event_common(iter_cpu); > } > } > > + g_assert(first_cpu); > rr_start_kick_timer(); > > - cpu = first_cpu; This final line seems to be unrelated. I'm not saying it's wrong, but it's certainly a change in behaviour. We no longer execute from first_cpu first. r~
diff --git a/accel/tcg/tcg-accel-ops-rr.c b/accel/tcg/tcg-accel-ops-rr.c index 028b385af9a..5ad3d617bce 100644 --- a/accel/tcg/tcg-accel-ops-rr.c +++ b/accel/tcg/tcg-accel-ops-rr.c @@ -197,20 +197,21 @@ static void *rr_cpu_thread_fn(void *arg) qemu_guest_random_seed_thread_part2(cpu->random_seed); /* wait for initial kick-off after machine start */ - while (first_cpu->stopped) { - qemu_cond_wait_bql(first_cpu->halt_cond); + while (cpu->stopped) { + CPUState *iter_cpu; + + qemu_cond_wait_bql(cpu->halt_cond); /* process any pending work */ - CPU_FOREACH(cpu) { - current_cpu = cpu; - qemu_wait_io_event_common(cpu); + CPU_FOREACH(iter_cpu) { + current_cpu = iter_cpu; + qemu_wait_io_event_common(iter_cpu); } } + g_assert(first_cpu); rr_start_kick_timer(); - cpu = first_cpu; - /* process any pending work */ cpu->exit_request = 1;
Let vCPUs wait for themselves being ready first, then other ones. This allows the first thread to starts without the global vcpu queue (thus &first_cpu) being populated. Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org> --- accel/tcg/tcg-accel-ops-rr.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-)