| Message ID | 20210916134748.67712-8-songmuchun@bytedance.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Use obj_cgroup APIs to charge the LRU pages | expand |
Hi Muchun,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on tj-cgroup/for-next]
[also build test WARNING on linus/master v5.15-rc1]
[cannot apply to hnaz-mm/master next-20210916]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Muchun-Song/Use-obj_cgroup-APIs-to-charge-the-LRU-pages/20210916-215452
base: https://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup.git for-next
config: x86_64-randconfig-m001-20210916 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
# https://github.com/0day-ci/linux/commit/938e77565fc42d6c0d53b0470d75b4055200afe1
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Muchun-Song/Use-obj_cgroup-APIs-to-charge-the-LRU-pages/20210916-215452
git checkout 938e77565fc42d6c0d53b0470d75b4055200afe1
# save the attached .config to linux build tree
mkdir build_dir
make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
mm/huge_memory.c:516:1: error: expected identifier or '(' before '+' token
516 | +static inline struct mem_cgroup *split_queue_memcg(struct deferred_split *queue)
| ^
In file included from include/asm-generic/bug.h:5,
from arch/x86/include/asm/bug.h:84,
from include/linux/bug.h:5,
from include/linux/mmdebug.h:5,
from include/linux/mm.h:9,
from mm/huge_memory.c:8:
mm/huge_memory.c: In function 'split_queue_lock':
mm/huge_memory.c:543:15: error: implicit declaration of function 'split_queue_memcg'; did you mean 'split_queue_lock'? [-Werror=implicit-function-declaration]
543 | if (unlikely(split_queue_memcg(queue) != page_memcg(head))) {
| ^~~~~~~~~~~~~~~~~
include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
| ^
>> mm/huge_memory.c:543:40: warning: comparison between pointer and integer
543 | if (unlikely(split_queue_memcg(queue) != page_memcg(head))) {
| ^~
include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
| ^
mm/huge_memory.c: In function 'split_queue_lock_irqsave':
mm/huge_memory.c:567:40: warning: comparison between pointer and integer
567 | if (unlikely(split_queue_memcg(queue) != page_memcg(head))) {
| ^~
include/linux/compiler.h:78:42: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
| ^
mm/huge_memory.c: In function 'deferred_split_huge_page':
mm/huge_memory.c:2839:8: warning: assignment to 'struct mem_cgroup *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
2839 | memcg = split_queue_memcg(ds_queue);
| ^
cc1: some warnings being treated as errors
vim +543 mm/huge_memory.c
533
534 static struct deferred_split *split_queue_lock(struct page *head)
535 {
536 struct deferred_split *queue;
537
538 rcu_read_lock();
539 retry:
540 queue = page_split_queue(head);
541 spin_lock(&queue->split_queue_lock);
542
> 543 if (unlikely(split_queue_memcg(queue) != page_memcg(head))) {
544 spin_unlock(&queue->split_queue_lock);
545 goto retry;
546 }
547
548 /*
549 * Preemption is disabled in the internal of spin_lock, which can serve
550 * as RCU read-side critical sections.
551 */
552 rcu_read_unlock();
553
554 return queue;
555 }
556
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 9d8dfa82991a..12950d4988e6 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -535,9 +535,22 @@ static struct deferred_split *split_queue_lock(struct page *head) { struct deferred_split *queue; + rcu_read_lock(); +retry: queue = page_split_queue(head); spin_lock(&queue->split_queue_lock); + if (unlikely(split_queue_memcg(queue) != page_memcg(head))) { + spin_unlock(&queue->split_queue_lock); + goto retry; + } + + /* + * Preemption is disabled in the internal of spin_lock, which can serve + * as RCU read-side critical sections. + */ + rcu_read_unlock(); + return queue; } @@ -546,9 +559,19 @@ split_queue_lock_irqsave(struct page *head, unsigned long *flags) { struct deferred_split *queue; + rcu_read_lock(); +retry: queue = page_split_queue(head); spin_lock_irqsave(&queue->split_queue_lock, *flags); + if (unlikely(split_queue_memcg(queue) != page_memcg(head))) { + spin_unlock_irqrestore(&queue->split_queue_lock, *flags); + goto retry; + } + + /* See the comments in split_queue_lock(). */ + rcu_read_unlock(); + return queue; }
Similar to lruvec lock, we use the same approach to make the split queue lock safe when LRU pages reparented. Signed-off-by: Muchun Song <songmuchun@bytedance.com> --- mm/huge_memory.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)