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R. Okajima" , Boqun Feng References: <20240807143922.919604-1-cmllamas@google.com> <20240807143922.919604-4-cmllamas@google.com> Content-Language: en-US From: Waiman Long In-Reply-To: <20240807143922.919604-4-cmllamas@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 8/7/24 10:39, Carlos Llamas wrote: > Define a macro AVG_LOCKDEP_CHAIN_DEPTH to document the magic number '5' > used in the calculation of MAX_LOCKDEP_CHAIN_HLOCKS. The number > represents the estimated average depth (number of locks held) of a lock > chain. The calculation of MAX_LOCKDEP_CHAIN_HLOCKS was first added in > commit 443cd507ce7f ("lockdep: add lock_class information to lock_chain > and output it"). > > Suggested-by: Waiman Long > Cc: Huang Ying > Cc: J. R. Okajima > Cc: Peter Zijlstra > Cc: Boqun Feng > Cc: Ingo Molnar > Cc: Will Deacon > Signed-off-by: Carlos Llamas > --- > v2: switched the comment for a macro as suggested by Waiman Long. > > kernel/locking/lockdep_internals.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h > index bbe9000260d0..20f9ef58d3d0 100644 > --- a/kernel/locking/lockdep_internals.h > +++ b/kernel/locking/lockdep_internals.h > @@ -119,7 +119,8 @@ static const unsigned long LOCKF_USED_IN_IRQ_READ = > > #define MAX_LOCKDEP_CHAINS (1UL << MAX_LOCKDEP_CHAINS_BITS) > > -#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS*5) > +#define AVG_LOCKDEP_CHAIN_DEPTH 5 > +#define MAX_LOCKDEP_CHAIN_HLOCKS (MAX_LOCKDEP_CHAINS * AVG_LOCKDEP_CHAIN_DEPTH) > > extern struct lock_chain lock_chains[]; > Acked-by: Waiman Long