path: root/lib
diff options
authorQian Cai <cai@gmx.us>2018-12-28 00:32:32 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2018-12-28 12:11:45 -0800
commita9ee3a63dbfff5237bc682b88c02d91a3c798e35 (patch)
treef79f0a161626b83a39021d078beed8422522d8da /lib
parent4494ce4fb4ff42946f48bbc8a5ac55ee18dca600 (diff)
debugobjects: call debug_objects_mem_init eariler
The current value of the early boot static pool size, 1024 is not big enough for systems with large number of CPUs with timer or/and workqueue objects selected. As the results, systems have 60+ CPUs with both timer and workqueue objects enabled could trigger "ODEBUG: Out of memory. ODEBUG disabled". Some debug objects are allocated during the early boot. Enabling some options like timers or workqueue objects may increase the size required significantly with large number of CPUs. For example, CONFIG_DEBUG_OBJECTS_TIMERS: No. CPUs x 2 (worker pool) objects: start_kernel workqueue_init_early init_worker_pool init_timer_key debug_object_init plus No. CPUs objects (CONFIG_HIGH_RES_TIMERS): sched_init hrtick_rq_init hrtimer_init CONFIG_DEBUG_OBJECTS_WORK: No. CPUs objects: vmalloc_init __init_work plus No. CPUs x 6 (workqueue) objects: workqueue_init_early alloc_workqueue __alloc_workqueue_key alloc_and_link_pwqs init_pwq Also, plus No. CPUs objects: perf_event_init __init_srcu_struct init_srcu_struct_fields init_srcu_struct_nodes __init_work However, none of the things are actually used or required before debug_objects_mem_init() is invoked, so just move the call right before vmalloc_init(). According to tglx, "the reason why the call is at this place in start_kernel() is historical. It's because back in the days when debugobjects were added the memory allocator was enabled way later than today." Link: http://lkml.kernel.org/r/20181126102407.1836-1-cai@gmx.us Signed-off-by: Qian Cai <cai@gmx.us> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <longman@redhat.com> Cc: Yang Shi <yang.shi@linux.alibaba.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
1 files changed, 3 insertions, 5 deletions
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 14afeeb7d6ef..55437fd5128b 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -1131,11 +1131,10 @@ static int __init debug_objects_replace_static_objects(void)
- * When debug_objects_mem_init() is called we know that only
- * one CPU is up, so disabling interrupts is enough
- * protection. This avoids the lockdep hell of lock ordering.
+ * debug_objects_mem_init() is now called early that only one CPU is up
+ * and interrupts have been disabled, so it is safe to replace the
+ * active object references.
- local_irq_disable();
/* Remove the statically allocated objects from the pool */
hlist_for_each_entry_safe(obj, tmp, &obj_pool, node)
@@ -1156,7 +1155,6 @@ static int __init debug_objects_replace_static_objects(void)
- local_irq_enable();
pr_debug("%d of %d active objects replaced\n",
cnt, obj_pool_used);