From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: [PATCH v6 25/99] page cache: Convert page deletion to XArray Date: Wed, 17 Jan 2018 12:20:49 -0800 Message-ID: <20180117202203.19756-26-willy@infradead.org> References: <20180117202203.19756-1-willy@infradead.org> Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=qbj9i5QcTqZoabnIEWTIZHsTgYM/VqOJ3iBYVoW1fKE=; b=Yr+HiQxQQIoeIonBYb1kr7s7x pu+ZYuUEg6jbjD83xmeG8EAy4V5owRZIbGdW0NvU3bWKS0Jjlv/gUMYiP5DRERfrddeubwrUcJoz0 MzfZujlV8UEQDiute87hd0sRfPuXFD5eqiHxSMSksYrODAkDobwuD6lzIS0QnKSUffE7rUk+lVHPs wNrpaIoHRl3W1nzdv/RG5c6iCEPxu3QAP1J9fjtnP1ohZrrz/yfeoYJtv5wOH2vw2nsCvNuGQvcW5 JpUQyajKU4BmBJqWZIx3H9BzKAoCPaAy2clZLmdy+ssn72d3S9G5PR9Czd6ym6T5ptlm3hoc2p/AY In-Reply-To: <20180117202203.19756-1-willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org> Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: Matthew Wilcox , linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-f2fs-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-nilfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-btrfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-xfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Bjorn Andersson , Stefano Stabellini , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-remoteproc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-s390-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, intel-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-sh-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, David Howells From: Matthew Wilcox The code is slightly shorter and simpler. Signed-off-by: Matthew Wilcox --- mm/filemap.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/mm/filemap.c b/mm/filemap.c index e6371b551de1..ed30d5310e50 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -112,30 +112,28 @@ * ->tasklist_lock (memory_failure, collect_procs_ao) */ -static void page_cache_tree_delete(struct address_space *mapping, +static void page_cache_delete(struct address_space *mapping, struct page *page, void *shadow) { - int i, nr; + XA_STATE(xas, &mapping->pages, page->index); + unsigned int i, nr; - /* hugetlb pages are represented by one entry in the radix tree */ + mapping_set_update(&xas, mapping); + + /* hugetlb pages are represented by a single entry in the xarray */ nr = PageHuge(page) ? 1 : hpage_nr_pages(page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageTail(page), page); VM_BUG_ON_PAGE(nr != 1 && shadow, page); - for (i = 0; i < nr; i++) { - struct radix_tree_node *node; - void **slot; - - __radix_tree_lookup(&mapping->pages, page->index + i, - &node, &slot); - - VM_BUG_ON_PAGE(!node && nr != 1, page); - - radix_tree_clear_tags(&mapping->pages, node, slot); - __radix_tree_replace(&mapping->pages, node, slot, shadow, - workingset_lookup_update(mapping)); + i = nr; +repeat: + xas_store(&xas, shadow); + xas_init_tags(&xas); + if (--i) { + xas_next(&xas); + goto repeat; } page->mapping = NULL; @@ -235,7 +233,7 @@ void __delete_from_page_cache(struct page *page, void *shadow) trace_mm_filemap_delete_from_page_cache(page); unaccount_page_cache_page(mapping, page); - page_cache_tree_delete(mapping, page, shadow); + page_cache_delete(mapping, page, shadow); } static void page_cache_free_page(struct address_space *mapping, -- 2.15.1 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html