On 10/05/22(Tue) 20:23, Mark Kettenis wrote:
> > Date: Tue, 10 May 2022 18:45:21 +0200
> > From: Martin Pieuchot <[email protected]>
> >
> > On 05/05/22(Thu) 14:54, Martin Pieuchot wrote:
> > > Diff below introduces a new wrapper to manipulate active/inactive page
> > > queues.
> > >
> > > ok?
> >
> > Anyone?
>
> Sorry I started looking at this and got distracted.
>
> I'm not sure about the changes to uvm_pageactivate(). It doesn't
> quite match what NetBSD does, but I guess NetBSD assumes that
> uvm_pageactiave() isn't called for a page that is already active? And
> that's something we can't guarantee?
It does look at what NetBSD did 15 years ago. We're not ready to synchronize
with NetBSD -current yet.
We're getting there!
> The diff is correct though in the sense that it is equivalent to the
> code we already have. So if this definitely is the direction you want
> to go:
>
> ok kettenis@
>
> > > Index: uvm/uvm_page.c
> > > ===================================================================
> > > RCS file: /cvs/src/sys/uvm/uvm_page.c,v
> > > retrieving revision 1.165
> > > diff -u -p -r1.165 uvm_page.c
> > > --- uvm/uvm_page.c 4 May 2022 14:58:26 -0000 1.165
> > > +++ uvm/uvm_page.c 5 May 2022 12:49:13 -0000
> > > @@ -987,16 +987,7 @@ uvm_pageclean(struct vm_page *pg)
> > > /*
> > > * now remove the page from the queues
> > > */
> > > - if (pg->pg_flags & PQ_ACTIVE) {
> > > - TAILQ_REMOVE(&uvm.page_active, pg, pageq);
> > > - flags_to_clear |= PQ_ACTIVE;
> > > - uvmexp.active--;
> > > - }
> > > - if (pg->pg_flags & PQ_INACTIVE) {
> > > - TAILQ_REMOVE(&uvm.page_inactive, pg, pageq);
> > > - flags_to_clear |= PQ_INACTIVE;
> > > - uvmexp.inactive--;
> > > - }
> > > + uvm_pagedequeue(pg);
> > >
> > > /*
> > > * if the page was wired, unwire it now.
> > > @@ -1243,16 +1234,7 @@ uvm_pagewire(struct vm_page *pg)
> > > MUTEX_ASSERT_LOCKED(&uvm.pageqlock);
> > >
> > > if (pg->wire_count == 0) {
> > > - if (pg->pg_flags & PQ_ACTIVE) {
> > > - TAILQ_REMOVE(&uvm.page_active, pg, pageq);
> > > - atomic_clearbits_int(&pg->pg_flags, PQ_ACTIVE);
> > > - uvmexp.active--;
> > > - }
> > > - if (pg->pg_flags & PQ_INACTIVE) {
> > > - TAILQ_REMOVE(&uvm.page_inactive, pg, pageq);
> > > - atomic_clearbits_int(&pg->pg_flags, PQ_INACTIVE);
> > > - uvmexp.inactive--;
> > > - }
> > > + uvm_pagedequeue(pg);
> > > uvmexp.wired++;
> > > }
> > > pg->wire_count++;
> > > @@ -1324,28 +1306,32 @@ uvm_pageactivate(struct vm_page *pg)
> > > KASSERT(uvm_page_owner_locked_p(pg));
> > > MUTEX_ASSERT_LOCKED(&uvm.pageqlock);
> > >
> > > + uvm_pagedequeue(pg);
> > > + if (pg->wire_count == 0) {
> > > + TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq);
> > > + atomic_setbits_int(&pg->pg_flags, PQ_ACTIVE);
> > > + uvmexp.active++;
> > > +
> > > + }
> > > +}
> > > +
> > > +/*
> > > + * uvm_pagedequeue: remove a page from any paging queue
> > > + */
> > > +void
> > > +uvm_pagedequeue(struct vm_page *pg)
> > > +{
> > > + if (pg->pg_flags & PQ_ACTIVE) {
> > > + TAILQ_REMOVE(&uvm.page_active, pg, pageq);
> > > + atomic_clearbits_int(&pg->pg_flags, PQ_ACTIVE);
> > > + uvmexp.active--;
> > > + }
> > > if (pg->pg_flags & PQ_INACTIVE) {
> > > TAILQ_REMOVE(&uvm.page_inactive, pg, pageq);
> > > atomic_clearbits_int(&pg->pg_flags, PQ_INACTIVE);
> > > uvmexp.inactive--;
> > > }
> > > - if (pg->wire_count == 0) {
> > > - /*
> > > - * if page is already active, remove it from list so we
> > > - * can put it at tail. if it wasn't active, then mark
> > > - * it active and bump active count
> > > - */
> > > - if (pg->pg_flags & PQ_ACTIVE)
> > > - TAILQ_REMOVE(&uvm.page_active, pg, pageq);
> > > - else {
> > > - atomic_setbits_int(&pg->pg_flags, PQ_ACTIVE);
> > > - uvmexp.active++;
> > > - }
> > > -
> > > - TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq);
> > > - }
> > > }
> > > -
> > > /*
> > > * uvm_pagezero: zero fill a page
> > > */
> > > Index: uvm/uvm_page.h
> > > ===================================================================
> > > RCS file: /cvs/src/sys/uvm/uvm_page.h,v
> > > retrieving revision 1.67
> > > diff -u -p -r1.67 uvm_page.h
> > > --- uvm/uvm_page.h 29 Jan 2022 06:25:33 -0000 1.67
> > > +++ uvm/uvm_page.h 5 May 2022 12:49:13 -0000
> > > @@ -224,6 +224,7 @@ boolean_t uvm_page_physget(paddr_t *);
> > > #endif
> > >
> > > void uvm_pageactivate(struct vm_page *);
> > > +void uvm_pagedequeue(struct vm_page *);
> > > vaddr_t uvm_pageboot_alloc(vsize_t);
> > > void uvm_pagecopy(struct vm_page *, struct vm_page *);
> > > void uvm_pagedeactivate(struct vm_page *);
> > >
> >
> >
