Hi Babu. On Mon, Sep 26, 2016 at 03:31:37PM -0700, Babu Moger wrote: > Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc. > > This feature limits the space used for "Lock debugging: prove locking > correctness" by about 4MB. The current sparc systms have the limitation of > 32MB size for kernel size including .text, .data and .bss sections. With > PROVE_LOCKING feature, the kernel size could grow beyond this limit and > causing system bootup issues. With this option, kernel limits the size > of the entries of lock_chains, stack_trace etc. so that kernel fits in > required size limit. This is only visible for sparc. > > Signed-off-by: Babu Moger <babu.moger@xxxxxxxxxx> > --- > lib/Kconfig.debug | 17 +++++++++++++++++ > 1 files changed, 17 insertions(+), 0 deletions(-) > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index b9cfdbf..c79de25 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1035,6 +1035,7 @@ config PROVE_LOCKING > select DEBUG_MUTEXES > select DEBUG_LOCK_ALLOC > select TRACE_IRQFLAGS > + select PROVE_LOCKING_SMALL if SPARC > default n > help > This feature enables the kernel to prove that all locking > @@ -1070,6 +1071,22 @@ config PROVE_LOCKING > > For more details, see Documentation/locking/lockdep-design.txt. > > +config PROVE_LOCKING_SMALL > + bool "Limit the space for prove locking correctness" > + depends on PROVE_LOCKING && SPARC > + help > + This feature limits the space used for "Lock debugging: prove > + locking correctness" by about 4MB. In sparc system, all the > + kernel's code, data, and bss, must have locked translations in > + the TLB so that it does not hit TLB misses. The current sparc > + chips have 8 TLB entries available that may be locked down, and > + with a 4mb page size, this gives a maximum of 32mb of memory for > + the kernel size. With PROVE_LOCKING feature, the kernel size could > + grow beyond this limit and causing system bootup issues. With > + this option, kernel limits the size of the entries of lock_chains, > + stack_trace etc. to debug PROVE_LOCKING so that kernel size fits > + in 32MB. This is only visible for SPARC. Since this is only relevant for sparc, and for sparc this is "select"ed, then there is limited/no gain having this as a visible menu config option. How about adding just a simple non-visible config symbol: config PROVE_LOCKING_SMALL bool The nice help text can be added to the H file, and the select can be move to the sparc/Kconfig file where it really belongs. Sam -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
