Re: [PATCH v5 07/14] iomap: track pending read bytes more optimally

Matthew Wilcox
2025-10-24T20:59:07Z

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:

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 ^#)