On 11/25/24 4:25 PM, Guenter Roeck wrote:
On 11/25/24 12:54, Waiman Long wrote:
On 11/25/24 3:23 PM, Guenter Roeck wrote:
On 11/25/24 12:06, Guenter Roeck wrote:
On 11/25/24 11:33, Waiman Long wrote:
[ ... ]
Fixing that finally gives me a clean run. Nevertheless, that
makes me wonder:
Should I just disable CONFIG_PROVE_RAW_LOCK_NESTING for sparc
runtime tests ?
If no one is tryng to ever enable PREEMPT_RT on SPARC, I suppose
you could disable CONFIG_PROVE_RAW_LOCK_NESTING to avoid the trouble.
SGTM. I'll do that unless someone gives me a good reason to keep it
enabled.
Actually it can not be disabled with a configuration flag. It is
automatically enabled. I'll have to disable PROVE_LOCKING to disable
it.
config PROVE_RAW_LOCK_NESTING
bool <---- no longer user configurable
depends on PROVE_LOCKING
default y
help
Enable the raw_spinlock vs. spinlock nesting checks which
ensure
that the lock nesting rules for PREEMPT_RT enabled kernels are
not violated.
I don't really like that, and I don't understand the logic behind it,
but it is what it is.
FWIW, the description of commit 560af5dc839 is misleading. It says
"Enable
PROVE_RAW_LOCK_NESTING _by default_" (emphasis mine). That is not
what the
commit does. It force-enables PROVE_RAW_LOCK_NESTING if
PROVE_LOCKING is
enabled. It is all or nothing.
I think we can relax it by
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 5d9eca035d47..bfdbd3fa2d29 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1399,7 +1399,7 @@ config PROVE_LOCKING
config PROVE_RAW_LOCK_NESTING
bool
depends on PROVE_LOCKING
- default y
+ default y if ARCH_SUPPORTS_RT
help
Enable the raw_spinlock vs. spinlock nesting checks which
ensure
that the lock nesting rules for PREEMPT_RT enabled kernels are
Sebastian, what do you think?
depends on PROVE_LOCKING && ARCH_SUPPORTS_RT
seems to make more sense to me.
That will work too, but that will enforce that arches with no
ARCH_SUPPORTS_RT will not be able to enable PROVE_RAW_LOCK_NESTING even
if people want to try it out.
Cheers,
Longman
