[PATCH v6 20/29] init/main: Delay initialization of the lockup detector after smp_init()

From: Ricardo Neri
Date: Thu May 05 2022 - 19:59:28 EST


Certain implementations of the hardlockup detector require support for
Inter-Processor Interrupt shorthands. On x86, support for these can only
be determined after all the possible CPUs have booted once (in
smp_init()). Other architectures may not need such check.

lockup_detector_init() only performs the initializations of data
structures of the lockup detector. Hence, there are no dependencies on
smp_init().

Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: "Ravi V. Shankar" <ravi.v.shankar@xxxxxxxxx>
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: x86@xxxxxxxxxx
Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
---
Changes since v5:
* Introduced this patch

Changes since v4:
* N/A

Changes since v3:
* N/A

Changes since v2:
* N/A

Changes since v1:
* N/A
---
init/main.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/init/main.c b/init/main.c
index 98182c3c2c4b..62c52c9e4c2b 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1600,9 +1600,11 @@ static noinline void __init kernel_init_freeable(void)

rcu_init_tasks_generic();
do_pre_smp_initcalls();
- lockup_detector_init();

smp_init();
+
+ lockup_detector_init();
+
sched_init_smp();

padata_init();
--
2.17.1