Andrew Morton
2025-Feb-11 05:00 UTC
[PATCH v2 03/17] mm/rmap: convert make_device_exclusive_range() to make_device_exclusive()
On Mon, 10 Feb 2025 20:37:45 +0100 David Hildenbrand <david at redhat.com> wrote:> The single "real" user in the tree of make_device_exclusive_range() always > requests making only a single address exclusive. The current implementation > is hard to fix for properly supporting anonymous THP / large folios and > for avoiding messing with rmap walks in weird ways. > > So let's always process a single address/page and return folio + page to > minimize page -> folio lookups. This is a preparation for further > changes. > > Reject any non-anonymous or hugetlb folios early, directly after GUP. > > While at it, extend the documentation of make_device_exclusive() to > clarify some things.x86_64 allmodconfig: drivers/gpu/drm/nouveau/nouveau_svm.c: In function 'nouveau_atomic_range_fault': drivers/gpu/drm/nouveau/nouveau_svm.c:612:68: error: 'folio' undeclared (first use in this function) 612 | page = make_device_exclusive(mm, start, drm->dev, &folio); | ^~~~~ drivers/gpu/drm/nouveau/nouveau_svm.c:612:68: note: each undeclared identifier is reported only once for each function it appears in
David Hildenbrand
2025-Feb-11 08:33 UTC
[PATCH v2 03/17] mm/rmap: convert make_device_exclusive_range() to make_device_exclusive()
On 11.02.25 06:00, Andrew Morton wrote:> On Mon, 10 Feb 2025 20:37:45 +0100 David Hildenbrand <david at redhat.com> wrote: > >> The single "real" user in the tree of make_device_exclusive_range() always >> requests making only a single address exclusive. The current implementation >> is hard to fix for properly supporting anonymous THP / large folios and >> for avoiding messing with rmap walks in weird ways. >> >> So let's always process a single address/page and return folio + page to >> minimize page -> folio lookups. This is a preparation for further >> changes. >> >> Reject any non-anonymous or hugetlb folios early, directly after GUP. >> >> While at it, extend the documentation of make_device_exclusive() to >> clarify some things. > > x86_64 allmodconfig: > > drivers/gpu/drm/nouveau/nouveau_svm.c: In function 'nouveau_atomic_range_fault': > drivers/gpu/drm/nouveau/nouveau_svm.c:612:68: error: 'folio' undeclared (first use in this function) > 612 | page = make_device_exclusive(mm, start, drm->dev, &folio); > | ^~~~~ > drivers/gpu/drm/nouveau/nouveau_svm.c:612:68: note: each undeclared identifier is reported only once for each function it appears inAh! Because I was carrying on the same branch SVM fixes [1] that are getting surprisingly little attention so far. The following sorts it out for now: From 337c68bf24af59f36477be11ea6ef7c7ce9aa8ae Mon Sep 17 00:00:00 2001 From: David Hildenbrand <david at redhat.com> Date: Tue, 11 Feb 2025 09:33:04 +0100 Subject: [PATCH] merge Signed-off-by: David Hildenbrand <david at redhat.com> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index 39e3740980bb7..1fed638b9eba8 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.c +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c @@ -590,6 +590,7 @@ static int nouveau_atomic_range_fault(struct nouveau_svmm *svmm, unsigned long timeout jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT); struct mm_struct *mm = svmm->notifier.mm; + struct folio *folio; struct page *page; unsigned long start = args->p.addr; unsigned long notifier_seq; -- 2.48.1 I'll resend [1] once this stuff here landed. Let me know if you want a full resend of this series, thanks. [1] https://lkml.kernel.org/r/20250124181524.3584236-1-david at redhat.com -- Cheers, David / dhildenb