From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75B291C84D3 for ; Fri, 14 Feb 2025 20:13:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739564039; cv=none; b=G1GxvLH2ukQra6k4al8eFQ7vYeP1OIJf0ZFKGjWXbaZJOjWhyxgM8S99EIR69xn6L1hVockQo4/M30tC7Hxb5taqGN0VETNWseBof5JjSmZvVzVxXYIxcr3otI9vFPKJNCKRW5NIDi8h54lbfShR2PvZjb8i9VBzPZzNyWgh89w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739564039; c=relaxed/simple; bh=11yDghk3Q1KQR9dyQo5cKk3cFl9oA0lfPn4n6ZcqiOk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KEpr4AOWwEg7hWv+FcemO39c41cCnqrGINhXXMDs0cHODr/3kKh/p7q25C+wg8+a63XCgbpLLuskO+18p8uXPQcGZ4ATkTnaUmkZt+5ADHeIeW+kLEQeowqBxXkLX3+LbDBx98yIoUhXoliZCHsFWkd8g1/LmvzPZdjjkpJQeyY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=rXv0vaa5; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="rXv0vaa5" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=fVBh7aaxMWrgdPSRhNEUp6jby7sv5vPC7kuSsBAFoKo=; b=rXv0vaa54mCblIpaapXigfgfw0 41pAAYZSHcUBiYziL6XmjiawVrMCkvCDnhF3+uHPURZKvrqyDxeP439DBjJl3Ky4C92EQIEVGLAVU VQZcI0k6puXOTRH9Fzsk2crQ8SYp6BmBeB55MgQpCtUS5u8NTALpN0z+pCXddgI8/lKuKVYVxIjby 2ew+8Bo7j7lj6jjn+fTLGKwti7RKK9L0Kod5D1ltwDamFQEfxqDyuikQcPRof4SCqnKgpZvlebwNe m5j5AFRmPWW058UoPMNhXFFGIgH1Di26Qy3IwqlxeYTfV94ZmWCiNHEweF9WhuHZ5c0Wo+hjCpHTZ JjtxbjtA==; Received: from willy by casper.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tj24F-0000000Bzz5-0gH6; Fri, 14 Feb 2025 20:13:43 +0000 Date: Fri, 14 Feb 2025 20:13:43 +0000 From: Matthew Wilcox To: Kairui Song Cc: linux-mm@kvack.org, Andrew Morton , Chris Li , Barry Song , Hugh Dickins , Yosry Ahmed , "Huang, Ying" , Baoquan He , Nhat Pham , Johannes Weiner , Kalesh Singh , linux-kernel@vger.kernel.org Subject: Re: [PATCH 7/7] mm, swap: simplify folio swap allocation Message-ID: References: <20250214175709.76029-1-ryncsn@gmail.com> <20250214175709.76029-8-ryncsn@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250214175709.76029-8-ryncsn@gmail.com> On Sat, Feb 15, 2025 at 01:57:09AM +0800, Kairui Song wrote: > @@ -1648,20 +1639,20 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc) > if (list_empty(&info->swaplist)) > list_add(&info->swaplist, &shmem_swaplist); > > - if (add_to_swap_cache(folio, swap, > - __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN, > - NULL) == 0) { > + if (folio_alloc_swap(folio, __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN)) { add_to_swap_cache() returns 0 on success or -errno. folio_alloc_swap returns true on success. That would seem to indicate you should change the polarity of this test? Or should folio_alloc_swap() return an errno? Is there value in distinguishing why we couldn't alloc swap (ENOMEM vs ENOSPC, perhaps?)