mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

mm, slab: split out the cpu offline variant of flush_slab() 

flush_slab() is called either as part IPI handler on given live cpu, or as a
cleanup on behalf of another cpu that went offline. The first case needs to
protect updating the kmem_cache_cpu fields with disabled irqs. Currently the
whole call happens with irqs disabled by the IPI handler, but the following
patch will change from IPI to workqueue, and flush_slab() will have to disable
irqs (to be replaced with a local lock later) in the critical part.

To prepare for this change, replace the call to flush_slab() for the dead cpu
handling with an opencoded variant that will not disable irqs nor take a local
lock.

Suggested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
This commit is contained in:
Vlastimil Babka 2021-06-03 19:17:42 +02:00
parent 0e7ac738f7
commit 08beb547a1
1 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
mm/slub.c
View File

@ -2511,9 +2511,17 @@ static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
{
struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
void *freelist = c->freelist;
struct page *page = c->page;
if (c->page)
flush_slab(s, c);
c->page = NULL;
c->freelist = NULL;
c->tid = next_tid(c->tid);
if (page) {
deactivate_slab(s, page, freelist);
stat(s, CPUSLAB_FLUSH);
}
unfreeze_partials_cpu(s, c);
}