From b3b9c187dc2544923a601733a85352b9ddaba9b3 Mon Sep 17 00:00:00 2001 From: Waiman Long Date: Thu, 6 Feb 2020 10:24:03 -0500 Subject: locking/lockdep: Decrement IRQ context counters when removing lock chain There are currently three counters to track the IRQ context of a lock chain - nr_hardirq_chains, nr_softirq_chains and nr_process_chains. They are incremented when a new lock chain is added, but they are not decremented when a lock chain is removed. That causes some of the statistic counts reported by /proc/lockdep_stats to be incorrect. IRQ Fix that by decrementing the right counter when a lock chain is removed. Since inc_chains() no longer accesses hardirq_context and softirq_context directly, it is moved out from the CONFIG_TRACE_IRQFLAGS conditional compilation block. Fixes: a0b0fd53e1e6 ("locking/lockdep: Free lock classes that are no longer in use") Signed-off-by: Waiman Long Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Link: https://lkml.kernel.org/r/20200206152408.24165-2-longman@redhat.com --- kernel/locking/lockdep_internals.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'kernel/locking/lockdep_internals.h') diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h index 18d85aebbb57..a525368b8cf6 100644 --- a/kernel/locking/lockdep_internals.h +++ b/kernel/locking/lockdep_internals.h @@ -106,6 +106,12 @@ static const unsigned long LOCKF_USED_IN_IRQ_READ = #define STACK_TRACE_HASH_SIZE 16384 #endif +/* + * Bit definitions for lock_chain.irq_context + */ +#define LOCK_CHAIN_SOFTIRQ_CONTEXT (1 << 0) +#define LOCK_CHAIN_HARDIRQ_CONTEXT (1 << 1) + #define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS) #define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5) -- cgit v1.2.1