| Message ID | 20211014151607.2171970-1-shakeelb@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] memcg: page_alloc: skip bulk allocator for __GFP_ACCOUNT | expand |
On 14.10.21 17:16, Shakeel Butt wrote: > The commit 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in > __vmalloc_area_node()") switched to bulk page allocator for order 0 > allocation backing vmalloc. However bulk page allocator does not support > __GFP_ACCOUNT allocations and there are several users of > kvmalloc(__GFP_ACCOUNT). > > For now make __GFP_ACCOUNT allocations bypass bulk page allocator. In > future if there is workload that can be significantly improved with the > bulk page allocator with __GFP_ACCCOUNT support, we can revisit the > decision. > > Fixes: 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") > Signed-off-by: Shakeel Butt <shakeelb@google.com> > --- > Changes since v1: > - do fallback allocation instead of failure, suggested by Michal Hocko. > - Added memcg_kmem_enabled() check, corrected by Vasily Averin > > mm/page_alloc.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 668edb16446a..9ca871dc8602 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5230,6 +5230,10 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, > if (unlikely(page_array && nr_pages - nr_populated == 0)) > goto out; > > + /* Bulk allocator does not support memcg accounting. */ > + if (memcg_kmem_enabled() && (gfp & __GFP_ACCOUNT)) > + goto failed; > + > /* Use the single page allocator for one page. */ > if (nr_pages - nr_populated == 1) > goto failed; > LGTM Acked-by: David Hildenbrand <david@redhat.com>
On Thu 14-10-21 08:16:07, Shakeel Butt wrote: > The commit 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in > __vmalloc_area_node()") switched to bulk page allocator for order 0 > allocation backing vmalloc. However bulk page allocator does not support > __GFP_ACCOUNT allocations and there are several users of > kvmalloc(__GFP_ACCOUNT). > > For now make __GFP_ACCOUNT allocations bypass bulk page allocator. In I would go with For now make __GFP_ACCOUNT allocations bypass the fast path of the bulk allocator and make it fallback to the regular page allocator as if the former failed. > future if there is workload that can be significantly improved with the > bulk page allocator with __GFP_ACCCOUNT support, we can revisit the > decision. > > Fixes: 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") > Signed-off-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Thanks! > --- > Changes since v1: > - do fallback allocation instead of failure, suggested by Michal Hocko. > - Added memcg_kmem_enabled() check, corrected by Vasily Averin > > mm/page_alloc.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 668edb16446a..9ca871dc8602 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5230,6 +5230,10 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, > if (unlikely(page_array && nr_pages - nr_populated == 0)) > goto out; > > + /* Bulk allocator does not support memcg accounting. */ > + if (memcg_kmem_enabled() && (gfp & __GFP_ACCOUNT)) > + goto failed; > + > /* Use the single page allocator for one page. */ > if (nr_pages - nr_populated == 1) > goto failed; > -- > 2.33.0.882.g93a45727a2-goog
On Thu, Oct 14, 2021 at 08:16:07AM -0700, Shakeel Butt wrote: > The commit 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in > __vmalloc_area_node()") switched to bulk page allocator for order 0 > allocation backing vmalloc. However bulk page allocator does not support > __GFP_ACCOUNT allocations and there are several users of > kvmalloc(__GFP_ACCOUNT). > > For now make __GFP_ACCOUNT allocations bypass bulk page allocator. In > future if there is workload that can be significantly improved with the > bulk page allocator with __GFP_ACCCOUNT support, we can revisit the > decision. > > Fixes: 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") > Signed-off-by: Shakeel Butt <shakeelb@google.com> > --- > Changes since v1: > - do fallback allocation instead of failure, suggested by Michal Hocko. Acked-by: Roman Gushchin <guro@fb.com> This looks indeed better! Thanks! > > mm/page_alloc.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 668edb16446a..9ca871dc8602 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5230,6 +5230,10 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, > if (unlikely(page_array && nr_pages - nr_populated == 0)) > goto out; > > + /* Bulk allocator does not support memcg accounting. */ > + if (memcg_kmem_enabled() && (gfp & __GFP_ACCOUNT)) > + goto failed; > + > /* Use the single page allocator for one page. */ > if (nr_pages - nr_populated == 1) > goto failed; > -- > 2.33.0.882.g93a45727a2-goog >
On Thu, Oct 14, 2021 at 08:16:07AM -0700, Shakeel Butt wrote: > The commit 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in > __vmalloc_area_node()") switched to bulk page allocator for order 0 > allocation backing vmalloc. However bulk page allocator does not support > __GFP_ACCOUNT allocations and there are several users of > kvmalloc(__GFP_ACCOUNT). > > For now make __GFP_ACCOUNT allocations bypass bulk page allocator. In > future if there is workload that can be significantly improved with the > bulk page allocator with __GFP_ACCCOUNT support, we can revisit the > decision. > > Fixes: 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") > Signed-off-by: Shakeel Butt <shakeelb@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
On 14.10.2021 18:16, Shakeel Butt wrote: > The commit 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in > __vmalloc_area_node()") switched to bulk page allocator for order 0 > allocation backing vmalloc. However bulk page allocator does not support > __GFP_ACCOUNT allocations and there are several users of > kvmalloc(__GFP_ACCOUNT). > > For now make __GFP_ACCOUNT allocations bypass bulk page allocator. In > future if there is workload that can be significantly improved with the > bulk page allocator with __GFP_ACCCOUNT support, we can revisit the > decision. > > Fixes: 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") > Signed-off-by: Shakeel Butt <shakeelb@google.com> Reported-and-tested-by: Vasily Averin <vvs@virtuozzo.com> > --- > Changes since v1: > - do fallback allocation instead of failure, suggested by Michal Hocko. > - Added memcg_kmem_enabled() check, corrected by Vasily Averin > > mm/page_alloc.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 668edb16446a..9ca871dc8602 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5230,6 +5230,10 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, > if (unlikely(page_array && nr_pages - nr_populated == 0)) > goto out; > > + /* Bulk allocator does not support memcg accounting. */ > + if (memcg_kmem_enabled() && (gfp & __GFP_ACCOUNT)) > + goto failed; > + > /* Use the single page allocator for one page. */ > if (nr_pages - nr_populated == 1) > goto failed; >
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 668edb16446a..9ca871dc8602 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5230,6 +5230,10 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, if (unlikely(page_array && nr_pages - nr_populated == 0)) goto out; + /* Bulk allocator does not support memcg accounting. */ + if (memcg_kmem_enabled() && (gfp & __GFP_ACCOUNT)) + goto failed; + /* Use the single page allocator for one page. */ if (nr_pages - nr_populated == 1) goto failed;
The commit 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") switched to bulk page allocator for order 0 allocation backing vmalloc. However bulk page allocator does not support __GFP_ACCOUNT allocations and there are several users of kvmalloc(__GFP_ACCOUNT). For now make __GFP_ACCOUNT allocations bypass bulk page allocator. In future if there is workload that can be significantly improved with the bulk page allocator with __GFP_ACCCOUNT support, we can revisit the decision. Fixes: 5c1f4e690eec ("mm/vmalloc: switch to bulk allocator in __vmalloc_area_node()") Signed-off-by: Shakeel Butt <shakeelb@google.com> --- Changes since v1: - do fallback allocation instead of failure, suggested by Michal Hocko. - Added memcg_kmem_enabled() check, corrected by Vasily Averin mm/page_alloc.c | 4 ++++ 1 file changed, 4 insertions(+)