struct lock_class does
const struct lock_trace * usage_traces[];
int name_version;
const char * name;
which wastes 4 bytes after "name_version".
Put pointer after pointers shrinking sizeof from 208 bytes to 200 bytes.
Space savings are considerable for such a trivial patch:
$ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux
add/remove: 0/0 grow/shrink: 1/11 up/down: 2/-65640 (-65638)
Function old new delta
check_irq_usage 2852 2854 +2
reacquire_held_locks 486 484 -2
lock_chain_get_class 41 39 -2
l_start 34 32 -2
check_noncircular 276 274 -2
print_usage_bug.part 688 683 -5
print_circular_bug 1017 1011 -6
hlock_conflict 141 135 -6
print_deadlock_bug 944 935 -9
mark_lock 3791 3769 -22
__lock_acquire 9801 9753 -48
lock_classes 1703936 1638400 -65536
Total: Before=21163908, After=21098270, chg -0.31%
Signed-off-by: Alexey Dobriyan <[email protected]>
---
include/linux/lockdep_types.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/include/linux/lockdep_types.h
+++ b/include/linux/lockdep_types.h
@@ -127,12 +127,12 @@ struct lock_class {
unsigned long usage_mask;
const struct lock_trace *usage_traces[LOCK_TRACE_STATES];
+ const char *name;
/*
* Generation counter, when doing certain classes of graph walking,
* to ensure that we check one node only once:
*/
int name_version;
- const char *name;
u8 wait_type_inner;
u8 wait_type_outer;
On 11/16/23 06:25, Alexey Dobriyan wrote:
> struct lock_class does
>
> const struct lock_trace * usage_traces[];
> int name_version;
> const char * name;
>
> which wastes 4 bytes after "name_version".
>
> Put pointer after pointers shrinking sizeof from 208 bytes to 200 bytes.
> Space savings are considerable for such a trivial patch:
>
> $ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux
> add/remove: 0/0 grow/shrink: 1/11 up/down: 2/-65640 (-65638)
> Function old new delta
> check_irq_usage 2852 2854 +2
> reacquire_held_locks 486 484 -2
> lock_chain_get_class 41 39 -2
> l_start 34 32 -2
> check_noncircular 276 274 -2
> print_usage_bug.part 688 683 -5
> print_circular_bug 1017 1011 -6
> hlock_conflict 141 135 -6
> print_deadlock_bug 944 935 -9
> mark_lock 3791 3769 -22
> __lock_acquire 9801 9753 -48
> lock_classes 1703936 1638400 -65536
> Total: Before=21163908, After=21098270, chg -0.31%
>
> Signed-off-by: Alexey Dobriyan <[email protected]>
> ---
>
> include/linux/lockdep_types.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> --- a/include/linux/lockdep_types.h
> +++ b/include/linux/lockdep_types.h
> @@ -127,12 +127,12 @@ struct lock_class {
> unsigned long usage_mask;
> const struct lock_trace *usage_traces[LOCK_TRACE_STATES];
>
> + const char *name;
> /*
> * Generation counter, when doing certain classes of graph walking,
> * to ensure that we check one node only once:
> */
> int name_version;
> - const char *name;
>
> u8 wait_type_inner;
> u8 wait_type_outer;
>
LGTM.
Acked-by: Waiman Long <[email protected]>