The patch titled Subject: mm/balloon_compaction.c: fix up comments has been removed from the -mm tree. Its filename was balloon-fix-up-comments.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: "Michael S. Tsirkin" <mst@xxxxxxxxxx> Subject: mm/balloon_compaction.c: fix up comments Lots of comments bitrotted. Fix them up. Link: http://lkml.kernel.org/r/20190718204333.26030-2-mst@xxxxxxxxxx Fixes: 418a3ab1e778 (mm/balloon_compaction: List interfaces) Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx> Reviewed-by: Wei Wang <wei.w.wang@xxxxxxxxx> Reviewed-by: Ralph Campbell <rcampbell@xxxxxxxxxx> Acked-by: Nadav Amit <namit@xxxxxxxxxx> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> Cc: Xavier Deguillard <xdeguillard@xxxxxxxxxx> Cc: Pankaj Gupta <pagupta@xxxxxxxxxx> Cc: Rik van Riel <riel@xxxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> Cc: Yang Zhang <yang.zhang.wz@xxxxxxxxx> Cc: Luiz Capitulino <lcapitulino@xxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/balloon_compaction.c | 67 ++++++++++++++++++++------------------ 1 file changed, 37 insertions(+), 30 deletions(-) --- a/mm/balloon_compaction.c~balloon-fix-up-comments +++ a/mm/balloon_compaction.c @@ -32,8 +32,8 @@ static void balloon_page_enqueue_one(str * @b_dev_info: balloon device descriptor where we will insert a new page to * @pages: pages to enqueue - allocated using balloon_page_alloc. * - * Driver must call it to properly enqueue a balloon pages before definitively - * removing it from the guest system. + * Driver must call this function to properly enqueue balloon pages before + * definitively removing them from the guest system. * * Return: number of pages that were enqueued. */ @@ -63,12 +63,13 @@ EXPORT_SYMBOL_GPL(balloon_page_list_enqu * @n_req_pages: number of requested pages. * * Driver must call this function to properly de-allocate a previous enlisted - * balloon pages before definetively releasing it back to the guest system. + * balloon pages before definitively releasing it back to the guest system. * This function tries to remove @n_req_pages from the ballooned pages and * return them to the caller in the @pages list. * - * Note that this function may fail to dequeue some pages temporarily empty due - * to compaction isolated pages. + * Note that this function may fail to dequeue some pages even if the balloon + * isn't empty - since the page list can be temporarily empty due to compaction + * of isolated pages. * * Return: number of pages that were added to the @pages list. */ @@ -112,12 +113,13 @@ EXPORT_SYMBOL_GPL(balloon_page_list_dequ /* * balloon_page_alloc - allocates a new page for insertion into the balloon - * page list. + * page list. * - * Driver must call it to properly allocate a new enlisted balloon page. - * Driver must call balloon_page_enqueue before definitively removing it from - * the guest system. This function returns the page address for the recently - * allocated page or NULL in the case we fail to allocate a new page this turn. + * Driver must call this function to properly allocate a new balloon page. + * Driver must call balloon_page_enqueue before definitively removing the page + * from the guest system. + * + * Return: struct page for the allocated page or NULL on allocation failure. */ struct page *balloon_page_alloc(void) { @@ -130,19 +132,15 @@ EXPORT_SYMBOL_GPL(balloon_page_alloc); /* * balloon_page_enqueue - inserts a new page into the balloon page list. * - * @b_dev_info: balloon device descriptor where we will insert a new page to + * @b_dev_info: balloon device descriptor where we will insert a new page * @page: new page to enqueue - allocated using balloon_page_alloc. * - * Driver must call it to properly enqueue a new allocated balloon page - * before definitively removing it from the guest system. + * Drivers must call this function to properly enqueue a new allocated balloon + * page before definitively removing the page from the guest system. * - * Drivers must not call balloon_page_enqueue on pages that have been - * pushed to a list with balloon_page_push before removing them with - * balloon_page_pop. To all pages on a list, use balloon_page_list_enqueue - * instead. - * - * This function returns the page address for the recently enqueued page or - * NULL in the case we fail to allocate a new page this turn. + * Drivers must not call balloon_page_enqueue on pages that have been pushed to + * a list with balloon_page_push before removing them with balloon_page_pop. To + * enqueue a list of pages, use balloon_page_list_enqueue instead. */ void balloon_page_enqueue(struct balloon_dev_info *b_dev_info, struct page *page) @@ -157,14 +155,23 @@ EXPORT_SYMBOL_GPL(balloon_page_enqueue); /* * balloon_page_dequeue - removes a page from balloon's page list and returns - * the its address to allow the driver release the page. + * its address to allow the driver to release the page. * @b_dev_info: balloon device decriptor where we will grab a page from. * - * Driver must call it to properly de-allocate a previous enlisted balloon page - * before definetively releasing it back to the guest system. - * This function returns the page address for the recently dequeued page or - * NULL in the case we find balloon's page list temporarily empty due to - * compaction isolated pages. + * Driver must call this function to properly dequeue a previously enqueued page + * before definitively releasing it back to the guest system. + * + * Caller must perform its own accounting to ensure that this + * function is called only if some pages are actually enqueued. + * + * Note that this function may fail to dequeue some pages even if there are + * some enqueued pages - since the page list can be temporarily empty due to + * the compaction of isolated pages. + * + * TODO: remove the caller accounting requirements, and allow caller to wait + * until all pages can be dequeued. + * + * Return: struct page for the dequeued page, or NULL if no page was dequeued. */ struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info) { @@ -177,9 +184,9 @@ struct page *balloon_page_dequeue(struct if (n_pages != 1) { /* * If we are unable to dequeue a balloon page because the page - * list is empty and there is no isolated pages, then something + * list is empty and there are no isolated pages, then something * went out of track and some balloon pages are lost. - * BUG() here, otherwise the balloon driver may get stuck into + * BUG() here, otherwise the balloon driver may get stuck in * an infinite loop while attempting to release all its pages. */ spin_lock_irqsave(&b_dev_info->pages_lock, flags); @@ -230,8 +237,8 @@ int balloon_page_migrate(struct address_ /* * We can not easily support the no copy case here so ignore it as it - * is unlikely to be use with ballon pages. See include/linux/hmm.h for - * user of the MIGRATE_SYNC_NO_COPY mode. + * is unlikely to be used with balloon pages. See include/linux/hmm.h + * for a user of the MIGRATE_SYNC_NO_COPY mode. */ if (mode == MIGRATE_SYNC_NO_COPY) return -EINVAL; _ Patches currently in -mm which might be from mst@xxxxxxxxxx are