Re: [PATCH v3 1/2] config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc

From: Babu Moger
Date: Thu Sep 29 2016 - 09:54:22 EST



On 9/28/2016 3:39 AM, Peter Zijlstra wrote:
On Tue, Sep 27, 2016 at 12:33:27PM -0700, Babu Moger wrote:
This new config parameter limits the space used for "Lock debugging:
prove locking correctness" by about 4MB. The current sparc systems 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 boot-up 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 not visible to user
and only used for sparc.

Signed-off-by: Babu Moger <babu.moger@xxxxxxxxxx>
You forgot to Cc Dave, and since you're touching sparc I need an Ack
from him before I can queue this.
Dave, Can you please take a look at the patch. Please ack it if it looks good.
Thanks

Dave?

---
arch/sparc/Kconfig | 1 +
lib/Kconfig.debug | 3 +++
2 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 59b0960..8da321c 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -44,6 +44,7 @@ config SPARC
select ARCH_HAS_SG_CHAIN
select CPU_NO_EFFICIENT_FFS
select HAVE_ARCH_HARDENED_USERCOPY
+ select PROVE_LOCKING_SMALL if PROVE_LOCKING
config SPARC32
def_bool !64BIT
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index cab7405..597e589 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1084,6 +1084,9 @@ config PROVE_LOCKING
For more details, see Documentation/locking/lockdep-design.txt.
+config PROVE_LOCKING_SMALL
+ bool
+
config LOCKDEP
bool
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
--
1.7.1