Re: [PATCH 3/7] xen/events: reduce externally visible helper functions

From: Oleksandr Tyshchenko
Date: Mon Nov 13 2023 - 10:53:44 EST




On 16.10.23 09:28, Juergen Gross wrote:


Hello Juergen

> get_evtchn_to_irq() has only one external user while irq_from_evtchn()
> provides the same functionality and is exported for a wider user base.
> Modify the only external user of get_evtchn_to_irq() to use
> irq_from_evtchn() instead and make get_evtchn_to_irq() static.
>
> evtchn_from_irq() and irq_from_virq() have a single external user and
> can easily be combined to a new helper irq_evtchn_from_virq() allowing
> to drop irq_from_virq() and to make evtchn_from_irq() static.
>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>


Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@xxxxxxxx>

Two NITs *NOT* directly related to current patch below.


> ---
> drivers/xen/events/events_2l.c | 8 ++++----
> drivers/xen/events/events_base.c | 13 +++++++++----
> drivers/xen/events/events_internal.h | 1 -
> include/xen/events.h | 4 ++--
> 4 files changed, 15 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/xen/events/events_2l.c b/drivers/xen/events/events_2l.c
> index b8f2f971c2f0..e3585330cf98 100644
> --- a/drivers/xen/events/events_2l.c
> +++ b/drivers/xen/events/events_2l.c
> @@ -171,11 +171,11 @@ static void evtchn_2l_handle_events(unsigned cpu, struct evtchn_loop_ctrl *ctrl)
> int i;
> struct shared_info *s = HYPERVISOR_shared_info;
> struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
> + evtchn_port_t evtchn;
>
> /* Timer interrupt has highest priority. */
> - irq = irq_from_virq(cpu, VIRQ_TIMER);
> + irq = irq_evtchn_from_virq(cpu, VIRQ_TIMER, &evtchn);
> if (irq != -1) {
> - evtchn_port_t evtchn = evtchn_from_irq(irq);

Most users of evtchn_from_irq() check returned evtchn via VALID_EVTCHN()
as it might be 0. But this user doesn't.


> word_idx = evtchn / BITS_PER_LONG;
> bit_idx = evtchn % BITS_PER_LONG;
> if (active_evtchns(cpu, s, word_idx) & (1ULL << bit_idx))
> @@ -328,9 +328,9 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id)
> for (i = 0; i < EVTCHN_2L_NR_CHANNELS; i++) {
> if (sync_test_bit(i, BM(sh->evtchn_pending))) {
> int word_idx = i / BITS_PER_EVTCHN_WORD;
> - printk(" %d: event %d -> irq %d%s%s%s\n",
> + printk(" %d: event %d -> irq %u%s%s%s\n",

checkpatch.pl says:

WARNING: printk() should include KERN_<LEVEL> facility level
#37: FILE: drivers/xen/events/events_2l.c:331:
+ printk(" %d: event %d -> irq %u%s%s%s\n",


> cpu_from_evtchn(i), i,
> - get_evtchn_to_irq(i),
> + irq_from_evtchn(i),
> sync_test_bit(word_idx, BM(&v->evtchn_pending_sel))
> ? "" : " l2-clear",
> !sync_test_bit(i, BM(sh->evtchn_mask))
>

[snip]