On Mon, Sep 02, 2013 at 04:51:17PM +0100, Martin MOKREJŠ wrote: > Catalin Marinas wrote: > > On Mon, Sep 02, 2013 at 04:44:52PM +0100, Max Filippov wrote: > >> On Mon, Sep 2, 2013 at 7:31 PM, Catalin Marinas <[email protected]> > >> wrote: > >>> On 31 August 2013 14:35, Martin MOKREJŠ <[email protected]> wrote: > >>>> never realized that my CPUs are gone if I compile into kernel kmemleak. > >>>> Is that really the aim? > >>>> > >>>> CONFIG_HAVE_DEBUG_KMEMLEAK=y > >>>> CONFIG_DEBUG_KMEMLEAK=y > >>>> CONFIG_DEBUG_KMEMLEAK_EARLY_LOG_SIZE=400 > >>>> # CONFIG_DEBUG_KMEMLEAK_TEST is not set > >>>> # CONFIG_DEBUG_KMEMLEAK_DEFAULT_OFF is not set > >>>> > >>>> 1. Why isn't there /sys/devices/system/cpu/cpu0/online file? > >>>> Does not matter if it contains 0 or 1. It just should exist. > >>> > >>> I can't really see how kmemleak would do this, maybe other config > >>> options that get set/cleared in the process of selecting kmemleak. Can > >> > >> Seems to be kmemcheck: from arch/x86/mm/kmemcheck/kmemcheck.c: > >> > >> int __init kmemcheck_init(void) > >> { > >> #ifdef CONFIG_SMP > >> /* > >> * Limit SMP to use a single CPU. We rely on the fact that this > >> code > >> * runs before SMP is set up. > >> */ > >> if (setup_max_cpus > 1) { > >> printk(KERN_INFO > >> "kmemcheck: Limiting number of CPUs to 1.\n"); > >> setup_max_cpus = 1; > >> } > >> #endif > > > > Ah, ok, not my problem then ;) > > Fine, so would somebody please update the help text accessible in "menuconfig" > for this entry? It should be clear that it has a huge performance impact if > enabled. > And, by compiling in it is enabled by default.
Otherwise, of no-one volunteers, please feel free to send a patch ;) -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
