From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 673911D61B7; Fri, 24 Oct 2025 21:37:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761341849; cv=none; b=CntJKHx+KcLrXMSFwjNfw15GeqbI+xnxGtX9hHxETAjMz/+2fIIjW3CxCF6ZhB6EXvZ0Ce5aXaTTwD3StCuUer2l6Wrb11XefZ5hUi0QOgGMM1XrkuqGW23yIQidLWQ4xnZDqIMP9S8KkI8A0MPMKyyq5+0WtMviPHS1i7mrDjk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761341849; c=relaxed/simple; bh=JGFHKzOCSuBxgkJ1cFZPD1F5rjn/Tfu8Ulz0zN8GHws=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=FGWqVV8Q1bMiW7WDXSRr+kDK+mFTFM/Lpy7I3uKM1EVh9PvJq3QNUfR9t/dwsqc0AtzMXYpiGG9ZuGqMe9U9KR3xjUXA+n6kJyAlnvvBMvXmn3xLzMRDdzOBQlxUcmcpcWmsPkk+ae8xQGBxLqqQDl1HJMxe4l//UZMEEwX5rUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fbN+kR+D; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fbN+kR+D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F0DF7C4CEF1; Fri, 24 Oct 2025 21:37:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761341849; bh=JGFHKzOCSuBxgkJ1cFZPD1F5rjn/Tfu8Ulz0zN8GHws=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=fbN+kR+DttC8Dct5cPj88N6eODAp7yTlBhv4+UGM0xUDwKMpVlFlf+coH9ZF/yNZ1 oEPtb+FB0D7yEFSYOJg+LqRN2+M3/xdv0k7OmKQVM5zknfUxAlOXgWztMjc9xT8niX J+/A33PyypvAIUXnvBpoV7evPZZTyu0A8U917z1vh3pwmnsaMjT1oZDsp2QGK4CORQ BmoBhVsL9RE/w0LdfprxlukaBxAa8xuI7FU87xqrLgG2ToQYXchJqyPbUFLGx0gYtb bPlPYINocxKx5NfgS7hkA99m7YV3mWLTVbaDjIAyjLZRX4+m4BOp0lJTso4xMyCici nfo5Bai+3wi6w== Date: Fri, 24 Oct 2025 14:37:28 -0700 From: "Darrick J. Wong" To: Matthew Wilcox Cc: Joanne Koong , Brian Foster , brauner@kernel.org, miklos@szeredi.hu, hch@infradead.org, hsiangkao@linux.alibaba.com, linux-block@vger.kernel.org, gfs2@lists.linux.dev, linux-fsdevel@vger.kernel.org, kernel-team@meta.com, linux-xfs@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v5 07/14] iomap: track pending read bytes more optimally Message-ID: <20251024213728.GL4015566@frogsfrogsfrogs> References: <20250926002609.1302233-1-joannelkoong@gmail.com> <20250926002609.1302233-8-joannelkoong@gmail.com> Precedence: bulk X-Mailing-List: linux-block@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: On Fri, Oct 24, 2025 at 09:59:01PM +0100, Matthew Wilcox wrote: > On Fri, Oct 24, 2025 at 12:22:32PM -0700, Joanne Koong wrote: > > > Feels like more filesystem people should be enabling CONFIG_DEBUG_VM > > > when testing (excluding performance testing of course; it'll do ugly > > > things to your performance numbers). > > > > Point taken. It looks like there's a bunch of other memory debugging > > configs as well. Do you recommend enabling all of these when testing? > > Do you have a particular .config you use for when you run tests? > > Our Kconfig is far too ornate. We could do with a "recommended for > kernel developers" profile. Here's what I'm currently using, though I > know it's changed over time: Is there any chance you could split the VM debug checks into cheap and expensive ones, and create another kconfig option so that we could do the cheap checks without having fstests take a lot longer? You could also implement shenanigans like the following: https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git/commit/?h=djwong-wtf&id=b739fff870384fd239abfd99ecee6bc47640794d To enable the expensive checks at runtime. (Yeah, I know, this is probably a 2 year project + bikeshed score of at least 30...) --D > CONFIG_X86_DEBUGCTLMSR=y > CONFIG_PM_DEBUG=y > CONFIG_PM_SLEEP_DEBUG=y > CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y > CONFIG_BLK_DEBUG_FS=y > CONFIG_PNP_DEBUG_MESSAGES=y > CONFIG_SCSI_DEBUG=m > CONFIG_EXT4_DEBUG=y > CONFIG_JFS_DEBUG=y > CONFIG_XFS_DEBUG=y > CONFIG_BTRFS_DEBUG=y > CONFIG_UFS_DEBUG=y > CONFIG_DEBUG_BUGVERBOSE=y > CONFIG_DEBUG_KERNEL=y > CONFIG_DEBUG_MISC=y > CONFIG_DEBUG_INFO=y > CONFIG_DEBUG_INFO_DWARF4=y > CONFIG_DEBUG_INFO_COMPRESSED_NONE=y > CONFIG_DEBUG_FS=y > CONFIG_DEBUG_FS_ALLOW_ALL=y > CONFIG_ARCH_HAS_EARLY_DEBUG=y > CONFIG_SLUB_DEBUG=y > CONFIG_ARCH_HAS_DEBUG_WX=y > CONFIG_HAVE_DEBUG_KMEMLEAK=y > CONFIG_SHRINKER_DEBUG=y > CONFIG_ARCH_HAS_DEBUG_VM_PGTABLE=y > CONFIG_DEBUG_VM_IRQSOFF=y > CONFIG_DEBUG_VM=y > CONFIG_ARCH_HAS_DEBUG_VIRTUAL=y > CONFIG_DEBUG_MEMORY_INIT=y > CONFIG_LOCK_DEBUGGING_SUPPORT=y > CONFIG_DEBUG_RT_MUTEXES=y > CONFIG_DEBUG_SPINLOCK=y > CONFIG_DEBUG_MUTEXES=y > CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y > CONFIG_DEBUG_RWSEMS=y > CONFIG_DEBUG_LOCK_ALLOC=y > CONFIG_DEBUG_LIST=y > CONFIG_X86_DEBUG_FPU=y > CONFIG_FAULT_INJECTION_DEBUG_FS=y > > (output from grep DEBUG .build/.config |grep -v ^#)