filemap: Convert tracing of page cache operations to folio

Pass the folio instead of a page.  The page was already implicitly a
folio as it accessed page->mapping directly.  Add the order of the folio
to the tracepoint, as this is important information.  Also drop printing
the address of the struct page as the pfn provides better information
than the struct page address.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>

include/trace/events/filemap.h

@@ -15,43 +15,45 @@
 
 DECLARE_EVENT_CLASS(mm_filemap_op_page_cache,
 
-	TP_PROTO(struct page *page),
+	TP_PROTO(struct folio *folio),
 
-	TP_ARGS(page),
+	TP_ARGS(folio),
 
 	TP_STRUCT__entry(
 		__field(unsigned long, pfn)
 		__field(unsigned long, i_ino)
 		__field(unsigned long, index)
 		__field(dev_t, s_dev)
+		__field(unsigned char, order)
 	),
 
 	TP_fast_assign(
-		__entry->pfn = page_to_pfn(page);
-		__entry->i_ino = page->mapping->host->i_ino;
-		__entry->index = page->index;
-		if (page->mapping->host->i_sb)
-			__entry->s_dev = page->mapping->host->i_sb->s_dev;
+		__entry->pfn = folio_pfn(folio);
+		__entry->i_ino = folio->mapping->host->i_ino;
+		__entry->index = folio->index;
+		if (folio->mapping->host->i_sb)
+			__entry->s_dev = folio->mapping->host->i_sb->s_dev;
 		else
-			__entry->s_dev = page->mapping->host->i_rdev;
+			__entry->s_dev = folio->mapping->host->i_rdev;
+		__entry->order = folio_order(folio);
 	),
 
-	TP_printk("dev %d:%d ino %lx page=%p pfn=0x%lx ofs=%lu",
+	TP_printk("dev %d:%d ino %lx pfn=0x%lx ofs=%lu order=%u",
 		MAJOR(__entry->s_dev), MINOR(__entry->s_dev),
 		__entry->i_ino,
-		pfn_to_page(__entry->pfn),
 		__entry->pfn,
-		__entry->index << PAGE_SHIFT)
+		__entry->index << PAGE_SHIFT,
+		__entry->order)
 );
 
 DEFINE_EVENT(mm_filemap_op_page_cache, mm_filemap_delete_from_page_cache,
-	TP_PROTO(struct page *page),
-	TP_ARGS(page)
+	TP_PROTO(struct folio *folio),
+	TP_ARGS(folio)
 	);
 
 DEFINE_EVENT(mm_filemap_op_page_cache, mm_filemap_add_to_page_cache,
-	TP_PROTO(struct page *page),
-	TP_ARGS(page)
+	TP_PROTO(struct folio *folio),
+	TP_ARGS(folio)
 	);
 
 TRACE_EVENT(filemap_set_wb_err,

mm/filemap.c

@@ -225,7 +225,7 @@ void __delete_from_page_cache(struct page *page, void *shadow)
 	struct folio *folio = page_folio(page);
 	struct address_space *mapping = page->mapping;
 
-	trace_mm_filemap_delete_from_page_cache(page);
+	trace_mm_filemap_delete_from_page_cache(folio);
 
 	filemap_unaccount_folio(mapping, folio);
 	page_cache_delete(mapping, folio, shadow);
@@ -346,9 +346,10 @@ void delete_from_page_cache_batch(struct address_space *mapping,
 	spin_lock(&mapping->host->i_lock);
 	xa_lock_irq(&mapping->i_pages);
 	for (i = 0; i < pagevec_count(pvec); i++) {
-		trace_mm_filemap_delete_from_page_cache(pvec->pages[i]);
+		struct folio *folio = page_folio(pvec->pages[i]);
 
-		filemap_unaccount_folio(mapping, page_folio(pvec->pages[i]));
+		trace_mm_filemap_delete_from_page_cache(folio);
+		filemap_unaccount_folio(mapping, folio);
 	}
 	page_cache_delete_batch(mapping, pvec);
 	xa_unlock_irq(&mapping->i_pages);
@@ -959,7 +960,7 @@ noinline int __filemap_add_folio(struct address_space *mapping,
 		goto error;
 	}
 
-	trace_mm_filemap_add_to_page_cache(&folio->page);
+	trace_mm_filemap_add_to_page_cache(folio);
 	return 0;
 error:
 	folio->mapping = NULL;