From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-362987-1516222303-2-15500585347135089082 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES enro, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-usb-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1516222303; b=Dr/XZfvIj5zY+Dkq8dM3XX190yhkEa7thF2vaX+dq2GcBLw YMFytKze4AJQCo6GRNmAFEcNT6wuvU1Z83GORIrs8T3sP5OeIVxD2s8r9sIjmKkm b587co7xAEhliP76nlNP+QMwB9vY5lbsYS1nZRWiWgHxvxxj35PG1cv0sAisbrQy zLoUgw004XuAJdXaBsaTeTzChhu9Sli00BziuE3bxUFpcbmOvfMJLiN9a2ZBXY8E 9/l0+ZF9vb9mAZJWQP4gmZkC2xX7xoRHqbfxkzxNG5yJst71kYFm7fqK+KpDCMy6 mb60PCgw7OruKD8tDzQ1FwbWT29PnRS3WAqOFCQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:sender:list-id; s=arctest; t=1516222303; bh=jvnvXgS/zp6kmS6YbKPWma7VmkmK2ur5UBfvV0J1UIg=; b=tfgzRUXODUpa Mvu7Fu3lLUQSALmLAZS6c6gxXZUGjROE84f8J2aQ1lTYk6HSUXYzc1GdcIdIjUu3 v73w2E+9/qFwLekuX9VNEwAJe8AN86TO3tfZhvh5mbcByfcBDZlrSrSj+q0a2U+f MKSQmVbamOP7XkEzV0zZPZDZ4W75Q/2O6cFykPkJXnWnN3b6YMpuTsJFjmFxZ6qz wuIk1fP8eVRxm7ZwxS3u0e+0F9z5HuRXR/NKInDgmyhBRABdA5X0WbFev8xT9ML7 AakxEFffsH+Z1aJf49uLruXw6g6MtSFoeoG4eNVgsO2wq+VW7U/Y1aO0MSYiiRo3 +MsW+9KZnw== ARC-Authentication-Results: i=1; mx2.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered; 2048-bit rsa key sha256) header.d=infradead.org header.i=@infradead.org header.b=iImZJE8J x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=bombadil.20170209; dmarc=none (p=none,has-list-id=yes,d=none) header.from=infradead.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-usb-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=infradead.org header.result=pass header_is_org_domain=yes Authentication-Results: mx2.messagingengine.com; arc=none (no signatures found); dkim=fail (message has been altered; 2048-bit rsa key sha256) header.d=infradead.org header.i=@infradead.org header.b=iImZJE8J x-bits=2048 x-keytype=rsa x-algorithm=sha256 x-selector=bombadil.20170209; dmarc=none (p=none,has-list-id=yes,d=none) header.from=infradead.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-usb-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=infradead.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932242AbeAQUv1 (ORCPT ); Wed, 17 Jan 2018 15:51:27 -0500 Received: from bombadil.infradead.org ([65.50.211.133]:34523 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753660AbeAQUWo (ORCPT ); Wed, 17 Jan 2018 15:22:44 -0500 From: Matthew Wilcox To: linux-kernel@vger.kernel.org Cc: Matthew Wilcox , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-nilfs@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-xfs@vger.kernel.org, linux-usb@vger.kernel.org, Bjorn Andersson , Stefano Stabellini , iommu@lists.linux-foundation.org, linux-remoteproc@vger.kernel.org, linux-s390@vger.kernel.org, intel-gfx@lists.freedesktop.org, cgroups@vger.kernel.org, linux-sh@vger.kernel.org, David Howells Subject: [PATCH v6 45/99] shmem: Convert shmem_wait_for_pins to XArray Date: Wed, 17 Jan 2018 12:21:09 -0800 Message-Id: <20180117202203.19756-46-willy@infradead.org> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180117202203.19756-1-willy@infradead.org> References: <20180117202203.19756-1-willy@infradead.org> Sender: linux-usb-owner@vger.kernel.org X-Mailing-List: linux-usb@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: From: Matthew Wilcox As with shmem_tag_pins(), hold the lock around the entire loop instead of acquiring & dropping it for each entry we're going to untag. Signed-off-by: Matthew Wilcox --- mm/shmem.c | 59 ++++++++++++++++++++++++----------------------------------- 1 file changed, 24 insertions(+), 35 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 2f41c7ceea18..e4a2eb1336be 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2636,9 +2636,7 @@ static void shmem_tag_pins(struct address_space *mapping) */ static int shmem_wait_for_pins(struct address_space *mapping) { - struct radix_tree_iter iter; - void **slot; - pgoff_t start; + XA_STATE(xas, &mapping->pages, 0); struct page *page; int error, scan; @@ -2646,7 +2644,9 @@ static int shmem_wait_for_pins(struct address_space *mapping) error = 0; for (scan = 0; scan <= LAST_SCAN; scan++) { - if (!radix_tree_tagged(&mapping->pages, SHMEM_TAG_PINNED)) + unsigned int tagged = 0; + + if (!xas_tagged(&xas, SHMEM_TAG_PINNED)) break; if (!scan) @@ -2654,45 +2654,34 @@ static int shmem_wait_for_pins(struct address_space *mapping) else if (schedule_timeout_killable((HZ << scan) / 200)) scan = LAST_SCAN; - start = 0; - rcu_read_lock(); - radix_tree_for_each_tagged(slot, &mapping->pages, &iter, - start, SHMEM_TAG_PINNED) { - - page = radix_tree_deref_slot(slot); - if (radix_tree_exception(page)) { - if (radix_tree_deref_retry(page)) { - slot = radix_tree_iter_retry(&iter); - continue; - } - - page = NULL; - } - - if (page && - page_count(page) - page_mapcount(page) != 1) { - if (scan < LAST_SCAN) - goto continue_resched; - + xas_set(&xas, 0); + xas_lock_irq(&xas); + xas_for_each_tag(&xas, page, ULONG_MAX, SHMEM_TAG_PINNED) { + bool clear = true; + if (xa_is_value(page)) + continue; + if (page_count(page) - page_mapcount(page) != 1) { /* * On the last scan, we clean up all those tags * we inserted; but make a note that we still * found pages pinned. */ - error = -EBUSY; + if (scan == LAST_SCAN) + error = -EBUSY; + else + clear = false; } + if (clear) + xas_clear_tag(&xas, SHMEM_TAG_PINNED); + if (++tagged % XA_CHECK_SCHED) + continue; - xa_lock_irq(&mapping->pages); - radix_tree_tag_clear(&mapping->pages, - iter.index, SHMEM_TAG_PINNED); - xa_unlock_irq(&mapping->pages); -continue_resched: - if (need_resched()) { - slot = radix_tree_iter_resume(slot, &iter); - cond_resched_rcu(); - } + xas_pause(&xas); + xas_unlock_irq(&xas); + cond_resched(); + xas_lock_irq(&xas); } - rcu_read_unlock(); + xas_unlock_irq(&xas); } return error; -- 2.15.1