[tip:,smp/core] locking/csd_lock: Add Kconfig option for csd_debug default
Commit Message
The following commit has been merged into the smp/core branch of tip:
Commit-ID: c52198601695851622f361d3f16456e9fc857629
Gitweb: https://git.kernel.org/tip/c52198601695851622f361d3f16456e9fc857629
Author: Paul E. McKenney <paulmck@kernel.org>
AuthorDate: Mon, 20 Mar 2023 17:55:13 -07:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Fri, 24 Mar 2023 11:01:25 +01:00
locking/csd_lock: Add Kconfig option for csd_debug default
The csd_debug kernel parameter works well, but is inconvenient in cases
where it is more closely associated with boot loaders or automation than
with a particular kernel version or release. Thererfore, provide a new
CSD_LOCK_WAIT_DEBUG_DEFAULT Kconfig option that defaults csd_debug to
1 when selected and 0 otherwise, with this latter being the default.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20230321005516.50558-1-paulmck@kernel.org
---
Documentation/admin-guide/kernel-parameters.txt | 6 ++++--
kernel/smp.c | 2 +-
lib/Kconfig.debug | 9 +++++++++
3 files changed, 14 insertions(+), 3 deletions(-)
@@ -893,8 +893,10 @@
handling. When switched on, additional debug data is
printed to the console in case a hanging CPU is
detected, and that CPU is pinged again in order to try
- to resolve the hang situation.
- 0: disable csdlock debugging (default)
+ to resolve the hang situation. The default value of
+ this option depends on the CSD_LOCK_WAIT_DEBUG_DEFAULT
+ Kconfig option.
+ 0: disable csdlock debugging
1: enable basic csdlock debugging (minor impact)
ext: enable extended csdlock debugging (more impact,
but more data)
@@ -158,7 +158,7 @@ void __init call_function_init(void)
#ifdef CONFIG_CSD_LOCK_WAIT_DEBUG
-static DEFINE_STATIC_KEY_FALSE(csdlock_debug_enabled);
+static DEFINE_STATIC_KEY_MAYBE(CONFIG_CSD_LOCK_WAIT_DEBUG_DEFAULT, csdlock_debug_enabled);
static DEFINE_STATIC_KEY_FALSE(csdlock_debug_extended);
static int __init csdlock_debug(char *str)
@@ -1480,6 +1480,15 @@ config CSD_LOCK_WAIT_DEBUG
include the IPI handler function currently executing (if any)
and relevant stack traces.
+config CSD_LOCK_WAIT_DEBUG_DEFAULT
+ bool "Default csd_lock_wait() debugging on at boot time"
+ depends on CSD_LOCK_WAIT_DEBUG
+ depends on 64BIT
+ default n
+ help
+ This option causes the csdlock_debug= kernel boot parameter to
+ default to 1 (basic debugging) instead of 0 (no debugging).
+
endmenu # lock debugging
config TRACE_IRQFLAGS