This is a note to let you know that I've just added the patch titled khugepaged: remove hpage from collapse_file() to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: khugepaged-remove-hpage-from-collapse_file.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 96cb391700104bba00e7908da152de0e959b42ad Author: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Date: Wed Apr 3 18:18:34 2024 +0100 khugepaged: remove hpage from collapse_file() [ Upstream commit 610ff817b981921213ae51e5c5f38c76c6f0405e ] Use new_folio throughout where we had been using hpage. Link: https://lkml.kernel.org/r/20240403171838.1445826-6-willy@xxxxxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Reviewed-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Stable-dep-of: 37f0b47c5143 ("mm: khugepaged: fix the arguments order in khugepaged_collapse_file trace point") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index 6e2ef1d4b0028..dc6eeef2d3dac 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -207,10 +207,10 @@ TRACE_EVENT(mm_khugepaged_scan_file, ); TRACE_EVENT(mm_khugepaged_collapse_file, - TP_PROTO(struct mm_struct *mm, struct page *hpage, pgoff_t index, + TP_PROTO(struct mm_struct *mm, struct folio *new_folio, pgoff_t index, bool is_shmem, unsigned long addr, struct file *file, int nr, int result), - TP_ARGS(mm, hpage, index, addr, is_shmem, file, nr, result), + TP_ARGS(mm, new_folio, index, addr, is_shmem, file, nr, result), TP_STRUCT__entry( __field(struct mm_struct *, mm) __field(unsigned long, hpfn) @@ -224,7 +224,7 @@ TRACE_EVENT(mm_khugepaged_collapse_file, TP_fast_assign( __entry->mm = mm; - __entry->hpfn = hpage ? page_to_pfn(hpage) : -1; + __entry->hpfn = new_folio ? folio_pfn(new_folio) : -1; __entry->index = index; __entry->addr = addr; __entry->is_shmem = is_shmem; diff --git a/mm/khugepaged.c b/mm/khugepaged.c index b197323450b5a..4b00592548f59 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1783,30 +1783,27 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, struct collapse_control *cc) { struct address_space *mapping = file->f_mapping; - struct page *hpage; struct page *page; - struct page *tmp; + struct page *tmp, *dst; struct folio *folio, *new_folio; pgoff_t index = 0, end = start + HPAGE_PMD_NR; LIST_HEAD(pagelist); XA_STATE_ORDER(xas, &mapping->i_pages, start, HPAGE_PMD_ORDER); int nr_none = 0, result = SCAN_SUCCEED; bool is_shmem = shmem_file(file); - int nr = 0; VM_BUG_ON(!IS_ENABLED(CONFIG_READ_ONLY_THP_FOR_FS) && !is_shmem); VM_BUG_ON(start & (HPAGE_PMD_NR - 1)); result = alloc_charge_folio(&new_folio, mm, cc); - hpage = &new_folio->page; if (result != SCAN_SUCCEED) goto out; - __SetPageLocked(hpage); + __folio_set_locked(new_folio); if (is_shmem) - __SetPageSwapBacked(hpage); - hpage->index = start; - hpage->mapping = mapping; + __folio_set_swapbacked(new_folio); + new_folio->index = start; + new_folio->mapping = mapping; /* * Ensure we have slots for all the pages in the range. This is @@ -2039,20 +2036,24 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, * The old pages are locked, so they won't change anymore. */ index = start; + dst = folio_page(new_folio, 0); list_for_each_entry(page, &pagelist, lru) { while (index < page->index) { - clear_highpage(hpage + (index % HPAGE_PMD_NR)); + clear_highpage(dst); index++; + dst++; } - if (copy_mc_highpage(hpage + (page->index % HPAGE_PMD_NR), page) > 0) { + if (copy_mc_highpage(dst, page) > 0) { result = SCAN_COPY_MC; goto rollback; } index++; + dst++; } while (index < end) { - clear_highpage(hpage + (index % HPAGE_PMD_NR)); + clear_highpage(dst); index++; + dst++; } if (nr_none) { @@ -2080,16 +2081,17 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, } /* - * If userspace observed a missing page in a VMA with a MODE_MISSING - * userfaultfd, then it might expect a UFFD_EVENT_PAGEFAULT for that - * page. If so, we need to roll back to avoid suppressing such an - * event. Since wp/minor userfaultfds don't give userspace any - * guarantees that the kernel doesn't fill a missing page with a zero - * page, so they don't matter here. + * If userspace observed a missing page in a VMA with + * a MODE_MISSING userfaultfd, then it might expect a + * UFFD_EVENT_PAGEFAULT for that page. If so, we need to + * roll back to avoid suppressing such an event. Since + * wp/minor userfaultfds don't give userspace any + * guarantees that the kernel doesn't fill a missing + * page with a zero page, so they don't matter here. * - * Any userfaultfds registered after this point will not be able to - * observe any missing pages due to the previously inserted retry - * entries. + * Any userfaultfds registered after this point will + * not be able to observe any missing pages due to the + * previously inserted retry entries. */ vma_interval_tree_foreach(vma, &mapping->i_mmap, start, end) { if (userfaultfd_missing(vma)) { @@ -2114,33 +2116,32 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, xas_lock_irq(&xas); } - folio = page_folio(hpage); - nr = folio_nr_pages(folio); if (is_shmem) - __lruvec_stat_mod_folio(folio, NR_SHMEM_THPS, nr); + __lruvec_stat_mod_folio(new_folio, NR_SHMEM_THPS, HPAGE_PMD_NR); else - __lruvec_stat_mod_folio(folio, NR_FILE_THPS, nr); + __lruvec_stat_mod_folio(new_folio, NR_FILE_THPS, HPAGE_PMD_NR); if (nr_none) { - __lruvec_stat_mod_folio(folio, NR_FILE_PAGES, nr_none); + __lruvec_stat_mod_folio(new_folio, NR_FILE_PAGES, nr_none); /* nr_none is always 0 for non-shmem. */ - __lruvec_stat_mod_folio(folio, NR_SHMEM, nr_none); + __lruvec_stat_mod_folio(new_folio, NR_SHMEM, nr_none); } /* - * Mark hpage as uptodate before inserting it into the page cache so - * that it isn't mistaken for an fallocated but unwritten page. + * Mark new_folio as uptodate before inserting it into the + * page cache so that it isn't mistaken for an fallocated but + * unwritten page. */ - folio_mark_uptodate(folio); - folio_ref_add(folio, HPAGE_PMD_NR - 1); + folio_mark_uptodate(new_folio); + folio_ref_add(new_folio, HPAGE_PMD_NR - 1); if (is_shmem) - folio_mark_dirty(folio); - folio_add_lru(folio); + folio_mark_dirty(new_folio); + folio_add_lru(new_folio); /* Join all the small entries into a single multi-index entry. */ xas_set_order(&xas, start, HPAGE_PMD_ORDER); - xas_store(&xas, folio); + xas_store(&xas, new_folio); WARN_ON_ONCE(xas_error(&xas)); xas_unlock_irq(&xas); @@ -2151,7 +2152,7 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, retract_page_tables(mapping, start); if (cc && !cc->is_khugepaged) result = SCAN_PTE_MAPPED_HUGEPAGE; - folio_unlock(folio); + folio_unlock(new_folio); /* * The collapse has succeeded, so free the old pages. @@ -2196,13 +2197,13 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr, smp_mb(); } - hpage->mapping = NULL; + new_folio->mapping = NULL; - unlock_page(hpage); - put_page(hpage); + folio_unlock(new_folio); + folio_put(new_folio); out: VM_BUG_ON(!list_empty(&pagelist)); - trace_mm_khugepaged_collapse_file(mm, hpage, index, is_shmem, addr, file, nr, result); + trace_mm_khugepaged_collapse_file(mm, new_folio, index, is_shmem, addr, file, HPAGE_PMD_NR, result); return result; }