On Tue, Jun 20, 2023 at 03:05:27AM +0000, 李培锋(wink) wrote: > On 16.06.23 11:21, lipeifeng@xxxxxxxx wrote: > >> From: lipeifeng <lipeifeng@xxxxxxxx> > >> > >> Some of shrinkers during shrink_slab would enter synchronous-wait due > >> to lock or other reasons, which would causes kswapd or direct_reclaim > >> to be blocked. > >> > >> This patch export shrink_slab so that it can be called in drivers > >> which can shrink memory independently. > >> > >> Signed-off-by: lipeifeng <lipeifeng@xxxxxxxx> > >> --- > >> mm/vmscan.c | 3 ++- > >> 1 file changed, 2 insertions(+), 1 deletion(-) > >> > >> diff --git a/mm/vmscan.c b/mm/vmscan.c index > >> 6d0cd2840cf0..2e54fa52e7ec 100644 > >> --- a/mm/vmscan.c > >> +++ b/mm/vmscan.c > >> @@ -1043,7 +1043,7 @@ static unsigned long shrink_slab_memcg(gfp_t gfp_mask, int nid, > >> * > >> * Returns the number of reclaimed slab objects. > >> */ > >> -static unsigned long shrink_slab(gfp_t gfp_mask, int nid, > >> +unsigned long shrink_slab(gfp_t gfp_mask, int nid, > >> struct mem_cgroup *memcg, > >> int priority) > >> { > >> @@ -1087,6 +1087,7 @@ static unsigned long shrink_slab(gfp_t gfp_mask, int nid, > >> cond_resched(); > >> return freed; > >> } > >> +EXPORT_SYMBOL_GPL(shrink_slab); > >> > >> static unsigned long drop_slab_node(int nid) > >> { > > > >It feels like something we don't want arbitrary drivers to call. > > > >Unrelated to that, this better be sent along with actual driver usage. > > Hi Sir: > > Virtually, we have implemented async shrink_slabd isolated from kswapd and direct_reclaim. > The goal above it is to avoid the sync-wait in kswapd or direct_reclaim due to some shrinkers. > > But the async shrink_slabd was only applied to mobile products so that I didn't make sure any > risk in other products. For the above reasons, I wanna merge the patch to export shrink_slab > and the patch of drivers would be considered to be pushed if I check all the risks. > > Some informal code files of driver are attached for your reference. You have to submit this as a real series, we can not accept exports for no in-kernel users (nor would you want us to, as that ends up being an unmaintainable mess.) So please resubmit this as a proper patch series, with the user of this function, and then it can be properly evaluated. As-is, this can not be accepted at all. thanks, greg k-h