Re: [PATCH 2/2] locking/spinlock_debug: Reduce lock cacheline contention

From: kbuild test robot
Date: Wed Feb 01 2017 - 14:44:11 EST


Hi Waiman,

[auto build test WARNING on tip/locking/core]
[also build test WARNING on v4.10-rc6 next-20170201]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url: https://github.com/0day-ci/linux/commits/Waiman-Long/locking-spinlock_debug-Change-it-to-a-mostly-fair-lock/20170202-024626
config: s390-default_defconfig (attached as .config)
compiler: s390x-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=s390

All warnings (new ones prefixed by >>):

block/blk-cgroup.c: In function 'blkg_destroy':
>> block/blk-cgroup.c:353:1: warning: the frame size of 1032 bytes is larger than 1024 bytes [-Wframe-larger-than=]
}
^
--
fs/lockd/svcsubs.c: In function 'nlmsvc_mark_resources':
>> fs/lockd/svcsubs.c:376:1: warning: the frame size of 1032 bytes is larger than 1024 bytes [-Wframe-larger-than=]
}
^

vim +353 block/blk-cgroup.c

e8989fae Tejun Heo 2012-03-05 337 list_del_init(&blkg->q_node);
9f13ef67 Tejun Heo 2012-03-05 338 hlist_del_init_rcu(&blkg->blkcg_node);
03aa264a Tejun Heo 2012-03-05 339
03aa264a Tejun Heo 2012-03-05 340 /*
a637120e Tejun Heo 2012-04-19 341 * Both setting lookup hint to and clearing it from @blkg are done
a637120e Tejun Heo 2012-04-19 342 * under queue_lock. If it's not pointing to @blkg now, it never
a637120e Tejun Heo 2012-04-19 343 * will. Hint assignment itself can race safely.
a637120e Tejun Heo 2012-04-19 344 */
ec6c676a Paul E. McKenney 2014-02-17 345 if (rcu_access_pointer(blkcg->blkg_hint) == blkg)
a637120e Tejun Heo 2012-04-19 346 rcu_assign_pointer(blkcg->blkg_hint, NULL);
a637120e Tejun Heo 2012-04-19 347
a637120e Tejun Heo 2012-04-19 348 /*
03aa264a Tejun Heo 2012-03-05 349 * Put the reference taken at the time of creation so that when all
03aa264a Tejun Heo 2012-03-05 350 * queues are gone, group can be destroyed.
03aa264a Tejun Heo 2012-03-05 351 */
03aa264a Tejun Heo 2012-03-05 352 blkg_put(blkg);
03aa264a Tejun Heo 2012-03-05 @353 }
03aa264a Tejun Heo 2012-03-05 354
9f13ef67 Tejun Heo 2012-03-05 355 /**
9f13ef67 Tejun Heo 2012-03-05 356 * blkg_destroy_all - destroy all blkgs associated with a request_queue
9f13ef67 Tejun Heo 2012-03-05 357 * @q: request_queue of interest
9f13ef67 Tejun Heo 2012-03-05 358 *
3c96cb32 Tejun Heo 2012-04-13 359 * Destroy all blkgs associated with @q.
9f13ef67 Tejun Heo 2012-03-05 360 */
3c96cb32 Tejun Heo 2012-04-13 361 static void blkg_destroy_all(struct request_queue *q)

:::::: The code at line 353 was first introduced by commit
:::::: 03aa264ac15637b6f98374270bcdf31400965505 blkcg: let blkcg core manage per-queue blkg list and counter

:::::: TO: Tejun Heo <tj@xxxxxxxxxx>
:::::: CC: Jens Axboe <axboe@xxxxxxxxx>

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