As CONFIG_DEBUG_PAGEALLOC can be enabled/disabled via kernel parameters we can optimize some cases by checking the enablement state. I have done s390 and x86 as examples. s390 should be ok, I tested several combinations, x86 seems to work as well, but I have some concerns about the 1GB pages. The previous code did not bother at all with CONFIG_DEBUG_PAGEALLOC and I do not fully understand why. Power can probably do the same, Michael/Ben? I am not sure about sparc. Sparc seems to allocate the TSB buffer really early. David? V1->V2: - replace DEBUG_PAGEALLOC(disabled/enabled) with DEBUG_PAGEALLOC dump_stack for s390/x86 - add /* CONFIG_DEBUG_PAGEALLOC */ to else and endif Christian Borntraeger (3): mm: provide debug_pagealloc_enabled() without CONFIG_DEBUG_PAGEALLOC x86: query dynamic DEBUG_PAGEALLOC setting s390: query dynamic DEBUG_PAGEALLOC setting arch/s390/kernel/dumpstack.c | 8 ++++---- arch/s390/mm/vmem.c | 10 ++++------ arch/x86/kernel/dumpstack.c | 5 ++--- arch/x86/mm/init.c | 7 ++++--- arch/x86/mm/pageattr.c | 14 ++++---------- include/linux/mm.h | 9 +++++++-- 6 files changed, 25 insertions(+), 28 deletions(-) -- 2.3.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>