search for: dequeued_pag

...s(-) > > diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c > index d3116be5a00f..300117f1a08f 100644 > --- a/mm/balloon_compaction.c > +++ b/mm/balloon_compaction.c > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > bool dequeued_page; > > dequeued_page = false; > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > /* > * Block others from accessing the 'page' while we get around > @@ -75,15 +76,14 @@ stru...

...s(-) > > diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c > index d3116be5a00f..300117f1a08f 100644 > --- a/mm/balloon_compaction.c > +++ b/mm/balloon_compaction.c > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > bool dequeued_page; > > dequeued_page = false; > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > /* > * Block others from accessing the 'page' while we get around > @@ -75,15 +76,14 @@ stru...

....c b/mm/balloon_compaction.c > > > index d3116be5a00f..300117f1a08f 100644 > > > --- a/mm/balloon_compaction.c > > > +++ b/mm/balloon_compaction.c > > > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > > > bool dequeued_page; > > > > > > dequeued_page = false; > > > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > > > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > > > /* > > > * Block others from accessing the '...

....c b/mm/balloon_compaction.c > > > index d3116be5a00f..300117f1a08f 100644 > > > --- a/mm/balloon_compaction.c > > > +++ b/mm/balloon_compaction.c > > > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > > > bool dequeued_page; > > > > > > dequeued_page = false; > > > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > > > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > > > /* > > > * Block others from accessing the '...

...t a/mm/balloon_compaction.c b/mm/balloon_compaction.c > > index d3116be5a00f..300117f1a08f 100644 > > --- a/mm/balloon_compaction.c > > +++ b/mm/balloon_compaction.c > > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > > bool dequeued_page; > > > > dequeued_page = false; > > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > > /* > > * Block others from accessing the 'page' while we get around...

During my compaction-related stuff, I encountered a bug with ballooning. With repeated inflating and deflating cycle, guest memory( ie, cat /proc/meminfo | grep MemTotal) is decreased and couldn't be recovered. The reason is balloon_lock doesn't cover release_pages_balloon so struct virtio_balloon fields could be overwritten by race of fill_balloon(e,g, vb->*pfns could be critical).

During my compaction-related stuff, I encountered a bug with ballooning. With repeated inflating and deflating cycle, guest memory( ie, cat /proc/meminfo | grep MemTotal) is decreased and couldn't be recovered. The reason is balloon_lock doesn't cover release_pages_balloon so struct virtio_balloon fields could be overwritten by race of fill_balloon(e,g, vb->*pfns could be critical).

...t a/mm/balloon_compaction.c b/mm/balloon_compaction.c > > index d3116be5a00f..300117f1a08f 100644 > > --- a/mm/balloon_compaction.c > > +++ b/mm/balloon_compaction.c > > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > > bool dequeued_page; > > > > dequeued_page = false; > > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > > /* > > * Block others from accessing the 'page' while we get around...

...16be..66d69c5 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -56,12 +56,34 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); */ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { - struct page *page, *tmp; + struct page *page; unsigned long flags; bool dequeued_page; + LIST_HEAD(processed); /* protected by b_dev_info->pages_lock */ dequeued_page = false; - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { + /* + * We need to go over b_dev_info->pages and lock each page, + * but b_dev_info->pages_lock must nest within page lo...

...16be..66d69c5 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -56,12 +56,34 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); */ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { - struct page *page, *tmp; + struct page *page; unsigned long flags; bool dequeued_page; + LIST_HEAD(processed); /* protected by b_dev_info->pages_lock */ dequeued_page = false; - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { + /* + * We need to go over b_dev_info->pages and lock each page, + * but b_dev_info->pages_lock must nest within page lo...

...hanged, 2 insertions(+), 2 deletions(-) diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c index d3116be5a00f..300117f1a08f 100644 --- a/mm/balloon_compaction.c +++ b/mm/balloon_compaction.c @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) bool dequeued_page; dequeued_page = false; + spin_lock_irqsave(&b_dev_info->pages_lock, flags); list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { /* * Block others from accessing the 'page' while we get around @@ -75,15 +76,14 @@ struct page *balloon_page_dequeue(struc...

...s(-) > > diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c > index d3116be5a00f..300117f1a08f 100644 > --- a/mm/balloon_compaction.c > +++ b/mm/balloon_compaction.c > @@ -61,6 +61,7 @@ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > bool dequeued_page; > > dequeued_page = false; > + spin_lock_irqsave(&b_dev_info->pages_lock, flags); > list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > /* > * Block others from accessing the 'page' while we get around > @@ -75,15 +76,14 @@ stru...

...e); > } > EXPORT_SYMBOL_GPL(balloon_page_enqueue); > > @@ -70,36 +161,13 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); > */ > struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > { > - struct page *page, *tmp; > unsigned long flags; > - bool dequeued_page; > + LIST_HEAD(pages); > + int n_pages; > > - dequeued_page = false; > - spin_lock_irqsave(&b_dev_info->pages_lock, flags); > - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > - /* > - * Block others from accessing the 'page' whil...

...dev_info->pages_lock, flags); - unlock_page(page); } EXPORT_SYMBOL_GPL(balloon_page_enqueue); @@ -70,36 +161,13 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); */ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { - struct page *page, *tmp; unsigned long flags; - bool dequeued_page; + LIST_HEAD(pages); + int n_pages; - dequeued_page = false; - spin_lock_irqsave(&b_dev_info->pages_lock, flags); - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { - /* - * Block others from accessing the 'page' while we get around - * establishing addit...

...dev_info->pages_lock, flags); - unlock_page(page); } EXPORT_SYMBOL_GPL(balloon_page_enqueue); @@ -70,36 +161,13 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); */ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { - struct page *page, *tmp; unsigned long flags; - bool dequeued_page; + LIST_HEAD(pages); + int n_pages; - dequeued_page = false; - spin_lock_irqsave(&b_dev_info->pages_lock, flags); - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { - /* - * Block others from accessing the 'page' while we get around - * establishing addit...

...e); > } > EXPORT_SYMBOL_GPL(balloon_page_enqueue); > > @@ -70,36 +156,13 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); > */ > struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > { > - struct page *page, *tmp; > unsigned long flags; > - bool dequeued_page; > + LIST_HEAD(pages); > + int n_pages; > > - dequeued_page = false; > - spin_lock_irqsave(&b_dev_info->pages_lock, flags); > - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > - /* > - * Block others from accessing the 'page' whil...

...e); > } > EXPORT_SYMBOL_GPL(balloon_page_enqueue); > > @@ -70,36 +162,13 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); > */ > struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) > { > - struct page *page, *tmp; > unsigned long flags; > - bool dequeued_page; > + LIST_HEAD(pages); > + int n_pages; > > - dequeued_page = false; > - spin_lock_irqsave(&b_dev_info->pages_lock, flags); > - list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) { > - /* > - * Block others from accessing the 'page' whil...

VMware balloon enhancements: adding support for memory compaction, memory shrinker (to prevent OOM) and splitting of refused pages to prevent recurring inflations. Patches 1-2: Support for compaction Patch 3: Support for memory shrinker - disabled by default Patch 4: Split refused pages to improve performance v2->v3: * Fixing wrong argument type (int->size_t) [Michael] * Fixing a comment

...ic64_read(&vb->num_pages)); > + for (num_pfns = 0; num_pfns < num; > + num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { > page = balloon_page_dequeue(vb_dev_info); If balloon_page_dequeue() can be concurrently called by both host's request and guest's OOM event, is (!dequeued_page) test in balloon_page_dequeue() safe? Is such concurrency needed? > if (!page) > break; > - set_page_pfns(vb, vb->pfns + vb->num_pfns, page); > + set_page_pfns(vb, pfns + num_pfns, page); > list_add(&page->lru, &pages); > - vb->num_pages -= VIRTI...

...ic64_read(&vb->num_pages)); > + for (num_pfns = 0; num_pfns < num; > + num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { > page = balloon_page_dequeue(vb_dev_info); If balloon_page_dequeue() can be concurrently called by both host's request and guest's OOM event, is (!dequeued_page) test in balloon_page_dequeue() safe? Is such concurrency needed? > if (!page) > break; > - set_page_pfns(vb, vb->pfns + vb->num_pfns, page); > + set_page_pfns(vb, pfns + num_pfns, page); > list_add(&page->lru, &pages); > - vb->num_pages -= VIRTI...