[PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[Roman Gushchin]

Currently bpf is using the memlock rlimit for the memory accounting.
This approach has its downsides and over time has created a significant
amount of problems:

1) The limit is per-user, but because most bpf operations are performed
   as root, the limit has a little value.

2) It's hard to come up with a specific maximum value. Especially because
   the counter is shared with non-bpf use cases (e.g. memlock()).
   Any specific value is either too low and creates false failures
   or is too high and useless.

3) Charging is not connected to the actual memory allocation. Bpf code
   should manually calculate the estimated cost and charge the counter,
   and then take care of uncharging, including all fail paths.
   It adds to the code complexity and makes it easy to leak a charge.

4) There is no simple way of getting the current value of the counter.
   We've used drgn for it, but it's far from being convenient.

5) Cryptic -EPERM is returned on exceeding the limit. Libbpf even had
   a function to "explain" this case for users.

6) rlimits are generally considered as (at least partially) obsolete.
   They do not provide a comprehensive system for the control of physical
   resources: memory, cpu, io etc. All resource control developments
   in the recent years were related to cgroups.

In order to overcome these problems let's switch to the memory cgroup-based
memory accounting of bpf objects. With the recent addition of the percpu
memory accounting, now it's possible to provide a comprehensive accounting
of the memory used by bpf programs and maps.

This approach has the following advantages:
1) The limit is per-cgroup and hierarchical. It's way more flexible and allows
   a better control over memory usage by different workloads.

2) The actual memory consumption is taken into account. It happens automatically
   on the allocation time if __GFP_ACCOUNT flags is passed. Uncharging is also
   performed automatically on releasing the memory. So the code on the bpf side
   becomes simpler and safer.

3) There is a simple way to get the current value and statistics.

Cgroup-based accounting adds new requirements:
1) The kernel config should have CONFIG_CGROUPS and CONFIG_MEMCG_KMEM enabled.
   These options are usually enabled, maybe excluding tiny builds for embedded
   devices.
2) The system should have a configured cgroup hierarchy, including reasonable
   memory limits and/or guarantees. Modern systems usually delegate this task
   to systemd or similar task managers.

Without meeting these requirements there are no limits on how much memory bpf
can use and a non-root user is able to hurt the system by allocating too much.
But because per-user rlimits do not provide a functional system to protect
and manage physical resources anyway, anyone who seriously depends on it,
should use cgroups.

When a bpf map is created, the memory cgroup of the process which creates
the map is recorded. Subsequently all memory allocation related to the bpf map
are charged to the same cgroup. It includes allocations made from interrupts
and by any processes. Bpf program memory is charged to the memory cgroup of
a process which loads the program.

The patchset consists of the following parts:
1) 4 mm patches are required on the mm side, otherwise vmallocs cannot be mapped
   to userspace
2) memcg-based accounting for various bpf objects: progs and maps
3) removal of the rlimit-based accounting
4) removal of rlimit adjustments in userspace samples


v9:
  - always charge the saved memory cgroup, by Daniel, Toke and Alexei
  - added bpf_map_kzalloc()
  - rebase and minor fixes

v8:
  - extended the cover letter to be more clear on new requirements, by Daniel
  - an approximate value is provided by map memlock info, by Alexei

v7:
  - introduced bpf_map_kmalloc_node() and bpf_map_alloc_percpu(), by Alexei
  - switched allocations made from an interrupt context to new helpers,
    by Daniel
  - rebase and minor fixes

v6:
  - rebased to the latest version of the remote charging API
  - fixed signatures, added acks

v5:
  - rebased to the latest version of the remote charging API
  - implemented kmem accounting from an interrupt context, by Shakeel
  - rebased to latest changes in mm allowed to map vmallocs to userspace
  - fixed a build issue in kselftests, by Alexei
  - fixed a use-after-free bug in bpf_map_free_deferred()
  - added bpf line info coverage, by Shakeel
  - split bpf map charging preparations into a separate patch

v4:
  - covered allocations made from an interrupt context, by Daniel
  - added some clarifications to the cover letter

v3:
  - droped the userspace part for further discussions/refinements,
    by Andrii and Song

v2:
  - fixed build issue, caused by the remaining rlimit-based accounting
    for sockhash maps


Roman Gushchin (34):
  mm: memcontrol: use helpers to read page's memcg data
  mm: memcontrol/slab: use helpers to access slab page's memcg_data
  mm: introduce page memcg flags
  mm: convert page kmemcg type to a page memcg flag
  bpf: memcg-based memory accounting for bpf progs
  bpf: prepare for memcg-based memory accounting for bpf maps
  bpf: memcg-based memory accounting for bpf maps
  bpf: refine memcg-based memory accounting for arraymap maps
  bpf: refine memcg-based memory accounting for cpumap maps
  bpf: memcg-based memory accounting for cgroup storage maps
  bpf: refine memcg-based memory accounting for devmap maps
  bpf: refine memcg-based memory accounting for hashtab maps
  bpf: memcg-based memory accounting for lpm_trie maps
  bpf: memcg-based memory accounting for bpf ringbuffer
  bpf: memcg-based memory accounting for bpf local storage maps
  bpf: refine memcg-based memory accounting for sockmap and sockhash
    maps
  bpf: refine memcg-based memory accounting for xskmap maps
  bpf: eliminate rlimit-based memory accounting for arraymap maps
  bpf: eliminate rlimit-based memory accounting for bpf_struct_ops maps
  bpf: eliminate rlimit-based memory accounting for cpumap maps
  bpf: eliminate rlimit-based memory accounting for cgroup storage maps
  bpf: eliminate rlimit-based memory accounting for devmap maps
  bpf: eliminate rlimit-based memory accounting for hashtab maps
  bpf: eliminate rlimit-based memory accounting for lpm_trie maps
  bpf: eliminate rlimit-based memory accounting for queue_stack_maps
    maps
  bpf: eliminate rlimit-based memory accounting for reuseport_array maps
  bpf: eliminate rlimit-based memory accounting for bpf ringbuffer
  bpf: eliminate rlimit-based memory accounting for sockmap and sockhash
    maps
  bpf: eliminate rlimit-based memory accounting for stackmap maps
  bpf: eliminate rlimit-based memory accounting for xskmap maps
  bpf: eliminate rlimit-based memory accounting for bpf local storage
    maps
  bpf: eliminate rlimit-based memory accounting infra for bpf maps
  bpf: eliminate rlimit-based memory accounting for bpf progs
  bpf: samples: do not touch RLIMIT_MEMLOCK

 fs/buffer.c                                   |   2 +-
 fs/iomap/buffered-io.c                        |   2 +-
 include/linux/bpf.h                           |  57 +++--
 include/linux/memcontrol.h                    | 215 +++++++++++++++-
 include/linux/mm.h                            |  22 --
 include/linux/mm_types.h                      |   5 +-
 include/linux/page-flags.h                    |  11 +-
 include/trace/events/writeback.h              |   2 +-
 kernel/bpf/arraymap.c                         |  30 +--
 kernel/bpf/bpf_local_storage.c                |  20 +-
 kernel/bpf/bpf_struct_ops.c                   |  19 +-
 kernel/bpf/core.c                             |  22 +-
 kernel/bpf/cpumap.c                           |  37 +--
 kernel/bpf/devmap.c                           |  25 +-
 kernel/bpf/hashtab.c                          |  43 ++--
 kernel/bpf/local_storage.c                    |  44 +---
 kernel/bpf/lpm_trie.c                         |  19 +-
 kernel/bpf/queue_stack_maps.c                 |  16 +-
 kernel/bpf/reuseport_array.c                  |  12 +-
 kernel/bpf/ringbuf.c                          |  35 +--
 kernel/bpf/stackmap.c                         |  16 +-
 kernel/bpf/syscall.c                          | 234 +++++++-----------
 kernel/fork.c                                 |   7 +-
 mm/debug.c                                    |   4 +-
 mm/huge_memory.c                              |   4 +-
 mm/memcontrol.c                               | 139 +++++------
 mm/page_alloc.c                               |   8 +-
 mm/page_io.c                                  |   6 +-
 mm/slab.h                                     |  38 +--
 mm/workingset.c                               |   2 +-
 net/core/sock_map.c                           |  42 +---
 net/xdp/xskmap.c                              |  15 +-
 samples/bpf/map_perf_test_user.c              |   6 -
 samples/bpf/offwaketime_user.c                |   6 -
 samples/bpf/sockex2_user.c                    |   2 -
 samples/bpf/sockex3_user.c                    |   2 -
 samples/bpf/spintest_user.c                   |   6 -
 samples/bpf/syscall_tp_user.c                 |   2 -
 samples/bpf/task_fd_query_user.c              |   6 -
 samples/bpf/test_lru_dist.c                   |   3 -
 samples/bpf/test_map_in_map_user.c            |   6 -
 samples/bpf/test_overhead_user.c              |   2 -
 samples/bpf/trace_event_user.c                |   2 -
 samples/bpf/tracex2_user.c                    |   6 -
 samples/bpf/tracex3_user.c                    |   6 -
 samples/bpf/tracex4_user.c                    |   6 -
 samples/bpf/tracex5_user.c                    |   3 -
 samples/bpf/tracex6_user.c                    |   3 -
 samples/bpf/xdp1_user.c                       |   6 -
 samples/bpf/xdp_adjust_tail_user.c            |   6 -
 samples/bpf/xdp_monitor_user.c                |   5 -
 samples/bpf/xdp_redirect_cpu_user.c           |   6 -
 samples/bpf/xdp_redirect_map_user.c           |   6 -
 samples/bpf/xdp_redirect_user.c               |   6 -
 samples/bpf/xdp_router_ipv4_user.c            |   6 -
 samples/bpf/xdp_rxq_info_user.c               |   6 -
 samples/bpf/xdp_sample_pkts_user.c            |   6 -
 samples/bpf/xdp_tx_iptunnel_user.c            |   6 -
 samples/bpf/xdpsock_user.c                    |   7 -
 .../selftests/bpf/progs/bpf_iter_bpf_map.c    |   2 +-
 .../selftests/bpf/progs/map_ptr_kern.c        |   7 -
 61 files changed, 533 insertions(+), 762 deletions(-)

-- 
2.26.2

[PATCH bpf-next v9 01/34] mm: memcontrol: use helpers to read page's memcg data

[Roman Gushchin]

Patch series "mm: allow mapping accounted kernel pages to userspace", v6.

Currently a non-slab kernel page which has been charged to a memory cgroup
can't be mapped to userspace.  The underlying reason is simple: PageKmemcg
flag is defined as a page type (like buddy, offline, etc), so it takes a
bit from a page->mapped counter.  Pages with a type set can't be mapped to
userspace.

But in general the kmemcg flag has nothing to do with mapping to
userspace.  It only means that the page has been accounted by the page
allocator, so it has to be properly uncharged on release.

Some bpf maps are mapping the vmalloc-based memory to userspace, and their
memory can't be accounted because of this implementation detail.

This patchset removes this limitation by moving the PageKmemcg flag into
one of the free bits of the page->mem_cgroup pointer.  Also it formalizes
accesses to the page->mem_cgroup and page->obj_cgroups using new helpers,
adds several checks and removes a couple of obsolete functions.  As the
result the code became more robust with fewer open-coded bit tricks.

This patch (of 4):

Currently there are many open-coded reads of the page->mem_cgroup pointer,
as well as a couple of read helpers, which are barely used.

It creates an obstacle on a way to reuse some bits of the pointer for
storing additional bits of information.  In fact, we already do this for
slab pages, where the last bit indicates that a pointer has an attached
vector of objcg pointers instead of a regular memcg pointer.

This commits uses 2 existing helpers and introduces a new helper to
converts all read sides to calls of these helpers:
  struct mem_cgroup *page_memcg(struct page *page);
  struct mem_cgroup *page_memcg_rcu(struct page *page);
  struct mem_cgroup *page_memcg_check(struct page *page);

page_memcg_check() is intended to be used in cases when the page can be a
slab page and have a memcg pointer pointing at objcg vector.  It does
check the lowest bit, and if set, returns NULL.  page_memcg() contains a
VM_BUG_ON_PAGE() check for the page not being a slab page.

To make sure nobody uses a direct access, struct page's
mem_cgroup/obj_cgroups is converted to unsigned long memcg_data.

Link: https://lkml.kernel.org/r/20201027001657.3398190-1-guro@fb.com
Link: https://lkml.kernel.org/r/20201027001657.3398190-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 fs/buffer.c                      |   2 +-
 fs/iomap/buffered-io.c           |   2 +-
 include/linux/memcontrol.h       | 114 ++++++++++++++++++++++++++---
 include/linux/mm.h               |  22 ------
 include/linux/mm_types.h         |   5 +-
 include/trace/events/writeback.h |   2 +-
 kernel/fork.c                    |   7 +-
 mm/debug.c                       |   4 +-
 mm/huge_memory.c                 |   4 +-
 mm/memcontrol.c                  | 121 ++++++++++++++-----------------
 mm/page_alloc.c                  |   4 +-
 mm/page_io.c                     |   6 +-
 mm/slab.h                        |   9 +--
 mm/workingset.c                  |   2 +-
 14 files changed, 184 insertions(+), 120 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 23f645657488..b56f99f82b5b 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -657,7 +657,7 @@ int __set_page_dirty_buffers(struct page *page)
 		} while (bh != head);
 	}
 	/*
-	 * Lock out page->mem_cgroup migration to keep PageDirty
+	 * Lock out page's memcg migration to keep PageDirty
 	 * synchronized with per-memcg dirty page counters.
 	 */
 	lock_page_memcg(page);
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 10cc7979ce38..16a1e82e3aeb 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -650,7 +650,7 @@ iomap_set_page_dirty(struct page *page)
 		return !TestSetPageDirty(page);
 
 	/*
-	 * Lock out page->mem_cgroup migration to keep PageDirty
+	 * Lock out page's memcg migration to keep PageDirty
 	 * synchronized with per-memcg dirty page counters.
 	 */
 	lock_page_memcg(page);
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index e391e3c56de5..f95c1433461c 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -343,6 +343,79 @@ struct mem_cgroup {
 
 extern struct mem_cgroup *root_mem_cgroup;
 
+/*
+ * page_memcg - get the memory cgroup associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the memory cgroup associated with the page,
+ * or NULL. This function assumes that the page is known to have a
+ * proper memory cgroup pointer. It's not safe to call this function
+ * against some type of pages, e.g. slab pages or ex-slab pages.
+ *
+ * Any of the following ensures page and memcg binding stability:
+ * - the page lock
+ * - LRU isolation
+ * - lock_page_memcg()
+ * - exclusive reference
+ */
+static inline struct mem_cgroup *page_memcg(struct page *page)
+{
+	VM_BUG_ON_PAGE(PageSlab(page), page);
+	return (struct mem_cgroup *)page->memcg_data;
+}
+
+/*
+ * page_memcg_rcu - locklessly get the memory cgroup associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the memory cgroup associated with the page,
+ * or NULL. This function assumes that the page is known to have a
+ * proper memory cgroup pointer. It's not safe to call this function
+ * against some type of pages, e.g. slab pages or ex-slab pages.
+ */
+static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
+{
+	VM_BUG_ON_PAGE(PageSlab(page), page);
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
+	return (struct mem_cgroup *)READ_ONCE(page->memcg_data);
+}
+
+/*
+ * page_memcg_check - get the memory cgroup associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the memory cgroup associated with the page,
+ * or NULL. This function unlike page_memcg() can take any  page
+ * as an argument. It has to be used in cases when it's not known if a page
+ * has an associated memory cgroup pointer or an object cgroups vector.
+ *
+ * Any of the following ensures page and memcg binding stability:
+ * - the page lock
+ * - LRU isolation
+ * - lock_page_memcg()
+ * - exclusive reference
+ */
+static inline struct mem_cgroup *page_memcg_check(struct page *page)
+{
+	/*
+	 * Because page->memcg_data might be changed asynchronously
+	 * for slab pages, READ_ONCE() should be used here.
+	 */
+	unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+	/*
+	 * The lowest bit set means that memcg isn't a valid
+	 * memcg pointer, but a obj_cgroups pointer.
+	 * In this case the page is shared and doesn't belong
+	 * to any specific memory cgroup.
+	 */
+	if (memcg_data & 0x1UL)
+		return NULL;
+
+	return (struct mem_cgroup *)memcg_data;
+}
+
 static __always_inline bool memcg_stat_item_in_bytes(int idx)
 {
 	if (idx == MEMCG_PERCPU_B)
@@ -743,15 +816,19 @@ static inline void mod_memcg_state(struct mem_cgroup *memcg,
 static inline void __mod_memcg_page_state(struct page *page,
 					  int idx, int val)
 {
-	if (page->mem_cgroup)
-		__mod_memcg_state(page->mem_cgroup, idx, val);
+	struct mem_cgroup *memcg = page_memcg(page);
+
+	if (memcg)
+		__mod_memcg_state(memcg, idx, val);
 }
 
 static inline void mod_memcg_page_state(struct page *page,
 					int idx, int val)
 {
-	if (page->mem_cgroup)
-		mod_memcg_state(page->mem_cgroup, idx, val);
+	struct mem_cgroup *memcg = page_memcg(page);
+
+	if (memcg)
+		mod_memcg_state(memcg, idx, val);
 }
 
 static inline unsigned long lruvec_page_state(struct lruvec *lruvec,
@@ -834,16 +911,17 @@ static inline void __mod_lruvec_page_state(struct page *page,
 					   enum node_stat_item idx, int val)
 {
 	struct page *head = compound_head(page); /* rmap on tail pages */
+	struct mem_cgroup *memcg = page_memcg(head);
 	pg_data_t *pgdat = page_pgdat(page);
 	struct lruvec *lruvec;
 
 	/* Untracked pages have no memcg, no lruvec. Update only the node */
-	if (!head->mem_cgroup) {
+	if (!memcg) {
 		__mod_node_page_state(pgdat, idx, val);
 		return;
 	}
 
-	lruvec = mem_cgroup_lruvec(head->mem_cgroup, pgdat);
+	lruvec = mem_cgroup_lruvec(memcg, pgdat);
 	__mod_lruvec_state(lruvec, idx, val);
 }
 
@@ -878,8 +956,10 @@ static inline void count_memcg_events(struct mem_cgroup *memcg,
 static inline void count_memcg_page_event(struct page *page,
 					  enum vm_event_item idx)
 {
-	if (page->mem_cgroup)
-		count_memcg_events(page->mem_cgroup, idx, 1);
+	struct mem_cgroup *memcg = page_memcg(page);
+
+	if (memcg)
+		count_memcg_events(memcg, idx, 1);
 }
 
 static inline void count_memcg_event_mm(struct mm_struct *mm,
@@ -941,6 +1021,22 @@ void mem_cgroup_split_huge_fixup(struct page *head);
 
 struct mem_cgroup;
 
+static inline struct mem_cgroup *page_memcg(struct page *page)
+{
+	return NULL;
+}
+
+static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
+{
+	WARN_ON_ONCE(!rcu_read_lock_held());
+	return NULL;
+}
+
+static inline struct mem_cgroup *page_memcg_check(struct page *page)
+{
+	return NULL;
+}
+
 static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
 {
 	return true;
@@ -1430,7 +1526,7 @@ static inline void mem_cgroup_track_foreign_dirty(struct page *page,
 	if (mem_cgroup_disabled())
 		return;
 
-	if (unlikely(&page->mem_cgroup->css != wb->memcg_css))
+	if (unlikely(&page_memcg(page)->css != wb->memcg_css))
 		mem_cgroup_track_foreign_dirty_slowpath(page, wb);
 }
 
diff --git a/include/linux/mm.h b/include/linux/mm.h
index db6ae4d3fb4e..6b0c9d2c1d10 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1484,28 +1484,6 @@ static inline void set_page_links(struct page *page, enum zone_type zone,
 #endif
 }
 
-#ifdef CONFIG_MEMCG
-static inline struct mem_cgroup *page_memcg(struct page *page)
-{
-	return page->mem_cgroup;
-}
-static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
-{
-	WARN_ON_ONCE(!rcu_read_lock_held());
-	return READ_ONCE(page->mem_cgroup);
-}
-#else
-static inline struct mem_cgroup *page_memcg(struct page *page)
-{
-	return NULL;
-}
-static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
-{
-	WARN_ON_ONCE(!rcu_read_lock_held());
-	return NULL;
-}
-#endif
-
 /*
  * Some inline functions in vmstat.h depend on page_zone()
  */
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 5a9238f6caad..80f5d755c037 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -199,10 +199,7 @@ struct page {
 	atomic_t _refcount;
 
 #ifdef CONFIG_MEMCG
-	union {
-		struct mem_cgroup *mem_cgroup;
-		struct obj_cgroup **obj_cgroups;
-	};
+	unsigned long memcg_data;
 #endif
 
 	/*
diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
index e7cbccc7c14c..39a40dfb578a 100644
--- a/include/trace/events/writeback.h
+++ b/include/trace/events/writeback.h
@@ -257,7 +257,7 @@ TRACE_EVENT(track_foreign_dirty,
 		__entry->ino		= inode ? inode->i_ino : 0;
 		__entry->memcg_id	= wb->memcg_css->id;
 		__entry->cgroup_ino	= __trace_wb_assign_cgroup(wb);
-		__entry->page_cgroup_ino = cgroup_ino(page->mem_cgroup->css.cgroup);
+		__entry->page_cgroup_ino = cgroup_ino(page_memcg(page)->css.cgroup);
 	),
 
 	TP_printk("bdi %s[%llu]: ino=%lu memcg_id=%u cgroup_ino=%lu page_cgroup_ino=%lu",
diff --git a/kernel/fork.c b/kernel/fork.c
index 6d266388d380..cbd4f6f58409 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -404,9 +404,10 @@ static int memcg_charge_kernel_stack(struct task_struct *tsk)
 
 		for (i = 0; i < THREAD_SIZE / PAGE_SIZE; i++) {
 			/*
-			 * If memcg_kmem_charge_page() fails, page->mem_cgroup
-			 * pointer is NULL, and memcg_kmem_uncharge_page() in
-			 * free_thread_stack() will ignore this page.
+			 * If memcg_kmem_charge_page() fails, page's
+			 * memory cgroup pointer is NULL, and
+			 * memcg_kmem_uncharge_page() in free_thread_stack()
+			 * will ignore this page.
 			 */
 			ret = memcg_kmem_charge_page(vm->pages[i], GFP_KERNEL,
 						     0);
diff --git a/mm/debug.c b/mm/debug.c
index ccca576b2899..8a40b3fefbeb 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -182,8 +182,8 @@ void __dump_page(struct page *page, const char *reason)
 		pr_warn("page dumped because: %s\n", reason);
 
 #ifdef CONFIG_MEMCG
-	if (!page_poisoned && page->mem_cgroup)
-		pr_warn("page->mem_cgroup:%px\n", page->mem_cgroup);
+	if (!page_poisoned && page->memcg_data)
+		pr_warn("pages's memcg:%lx\n", page->memcg_data);
 #endif
 }
 
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 9474dbc150ed..cedfb3503411 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -470,7 +470,7 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma)
 #ifdef CONFIG_MEMCG
 static inline struct deferred_split *get_deferred_split_queue(struct page *page)
 {
-	struct mem_cgroup *memcg = compound_head(page)->mem_cgroup;
+	struct mem_cgroup *memcg = page_memcg(compound_head(page));
 	struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));
 
 	if (memcg)
@@ -2765,7 +2765,7 @@ void deferred_split_huge_page(struct page *page)
 {
 	struct deferred_split *ds_queue = get_deferred_split_queue(page);
 #ifdef CONFIG_MEMCG
-	struct mem_cgroup *memcg = compound_head(page)->mem_cgroup;
+	struct mem_cgroup *memcg = page_memcg(compound_head(page));
 #endif
 	unsigned long flags;
 
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3dcbf24d2227..3968d68503cb 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -533,7 +533,7 @@ struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page)
 {
 	struct mem_cgroup *memcg;
 
-	memcg = page->mem_cgroup;
+	memcg = page_memcg(page);
 
 	if (!memcg || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		memcg = root_mem_cgroup;
@@ -560,16 +560,7 @@ ino_t page_cgroup_ino(struct page *page)
 	unsigned long ino = 0;
 
 	rcu_read_lock();
-	memcg = page->mem_cgroup;
-
-	/*
-	 * The lowest bit set means that memcg isn't a valid
-	 * memcg pointer, but a obj_cgroups pointer.
-	 * In this case the page is shared and doesn't belong
-	 * to any specific memory cgroup.
-	 */
-	if ((unsigned long) memcg & 0x1UL)
-		memcg = NULL;
+	memcg = page_memcg_check(page);
 
 	while (memcg && !(memcg->css.flags & CSS_ONLINE))
 		memcg = parent_mem_cgroup(memcg);
@@ -1050,7 +1041,7 @@ EXPORT_SYMBOL(get_mem_cgroup_from_mm);
  */
 struct mem_cgroup *get_mem_cgroup_from_page(struct page *page)
 {
-	struct mem_cgroup *memcg = page->mem_cgroup;
+	struct mem_cgroup *memcg = page_memcg(page);
 
 	if (mem_cgroup_disabled())
 		return NULL;
@@ -1349,7 +1340,7 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd
 		goto out;
 	}
 
-	memcg = page->mem_cgroup;
+	memcg = page_memcg(page);
 	/*
 	 * Swapcache readahead pages are added to the LRU - and
 	 * possibly migrated - before they are charged.
@@ -2109,7 +2100,7 @@ void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
 }
 
 /**
- * lock_page_memcg - lock a page->mem_cgroup binding
+ * lock_page_memcg - lock a page and memcg binding
  * @page: the page
  *
  * This function protects unlocked LRU pages from being moved to
@@ -2141,7 +2132,7 @@ struct mem_cgroup *lock_page_memcg(struct page *page)
 	if (mem_cgroup_disabled())
 		return NULL;
 again:
-	memcg = head->mem_cgroup;
+	memcg = page_memcg(head);
 	if (unlikely(!memcg))
 		return NULL;
 
@@ -2149,7 +2140,7 @@ struct mem_cgroup *lock_page_memcg(struct page *page)
 		return memcg;
 
 	spin_lock_irqsave(&memcg->move_lock, flags);
-	if (memcg != head->mem_cgroup) {
+	if (memcg != page_memcg(head)) {
 		spin_unlock_irqrestore(&memcg->move_lock, flags);
 		goto again;
 	}
@@ -2187,14 +2178,14 @@ void __unlock_page_memcg(struct mem_cgroup *memcg)
 }
 
 /**
- * unlock_page_memcg - unlock a page->mem_cgroup binding
+ * unlock_page_memcg - unlock a page and memcg binding
  * @page: the page
  */
 void unlock_page_memcg(struct page *page)
 {
 	struct page *head = compound_head(page);
 
-	__unlock_page_memcg(head->mem_cgroup);
+	__unlock_page_memcg(page_memcg(head));
 }
 EXPORT_SYMBOL(unlock_page_memcg);
 
@@ -2884,7 +2875,7 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
 
 static void commit_charge(struct page *page, struct mem_cgroup *memcg)
 {
-	VM_BUG_ON_PAGE(page->mem_cgroup, page);
+	VM_BUG_ON_PAGE(page_memcg(page), page);
 	/*
 	 * Any of the following ensures page->mem_cgroup stability:
 	 *
@@ -2893,7 +2884,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg)
 	 * - lock_page_memcg()
 	 * - exclusive reference
 	 */
-	page->mem_cgroup = memcg;
+	page->memcg_data = (unsigned long)memcg;
 }
 
 #ifdef CONFIG_MEMCG_KMEM
@@ -2908,8 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
 	if (!vec)
 		return -ENOMEM;
 
-	if (cmpxchg(&page->obj_cgroups, NULL,
-		    (struct obj_cgroup **) ((unsigned long)vec | 0x1UL)))
+	if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL))
 		kfree(vec);
 	else
 		kmemleak_not_leak(vec);
@@ -2920,6 +2910,12 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
 /*
  * Returns a pointer to the memory cgroup to which the kernel object is charged.
  *
+ * A passed kernel object can be a slab object or a generic kernel page, so
+ * different mechanisms for getting the memory cgroup pointer should be used.
+ * In certain cases (e.g. kernel stacks or large kmallocs with SLUB) the caller
+ * can not know for sure how the kernel object is implemented.
+ * mem_cgroup_from_obj() can be safely used in such cases.
+ *
  * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(),
  * cgroup_mutex, etc.
  */
@@ -2932,17 +2928,6 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
 
 	page = virt_to_head_page(p);
 
-	/*
-	 * If page->mem_cgroup is set, it's either a simple mem_cgroup pointer
-	 * or a pointer to obj_cgroup vector. In the latter case the lowest
-	 * bit of the pointer is set.
-	 * The page->mem_cgroup pointer can be asynchronously changed
-	 * from NULL to (obj_cgroup_vec | 0x1UL), but can't be changed
-	 * from a valid memcg pointer to objcg vector or back.
-	 */
-	if (!page->mem_cgroup)
-		return NULL;
-
 	/*
 	 * Slab objects are accounted individually, not per-page.
 	 * Memcg membership data for each individual object is saved in
@@ -2960,8 +2945,14 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
 		return NULL;
 	}
 
-	/* All other pages use page->mem_cgroup */
-	return page->mem_cgroup;
+	/*
+	 * page_memcg_check() is used here, because page_has_obj_cgroups()
+	 * check above could fail because the object cgroups vector wasn't set
+	 * at that moment, but it can be set concurrently.
+	 * page_memcg_check(page) will guarantee that a proper memory
+	 * cgroup pointer or NULL will be returned.
+	 */
+	return page_memcg_check(page);
 }
 
 __always_inline struct obj_cgroup *get_obj_cgroup_from_current(void)
@@ -3099,7 +3090,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
 	if (memcg && !mem_cgroup_is_root(memcg)) {
 		ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
 		if (!ret) {
-			page->mem_cgroup = memcg;
+			page->memcg_data = (unsigned long)memcg;
 			__SetPageKmemcg(page);
 			return 0;
 		}
@@ -3115,7 +3106,7 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
  */
 void __memcg_kmem_uncharge_page(struct page *page, int order)
 {
-	struct mem_cgroup *memcg = page->mem_cgroup;
+	struct mem_cgroup *memcg = page_memcg(page);
 	unsigned int nr_pages = 1 << order;
 
 	if (!memcg)
@@ -3123,7 +3114,7 @@ void __memcg_kmem_uncharge_page(struct page *page, int order)
 
 	VM_BUG_ON_PAGE(mem_cgroup_is_root(memcg), page);
 	__memcg_kmem_uncharge(memcg, nr_pages);
-	page->mem_cgroup = NULL;
+	page->memcg_data = 0;
 	css_put(&memcg->css);
 
 	/* slab pages do not have PageKmemcg flag set */
@@ -3274,7 +3265,7 @@ void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size)
  */
 void mem_cgroup_split_huge_fixup(struct page *head)
 {
-	struct mem_cgroup *memcg = head->mem_cgroup;
+	struct mem_cgroup *memcg = page_memcg(head);
 	int i;
 
 	if (mem_cgroup_disabled())
@@ -3282,7 +3273,7 @@ void mem_cgroup_split_huge_fixup(struct page *head)
 
 	for (i = 1; i < HPAGE_PMD_NR; i++) {
 		css_get(&memcg->css);
-		head[i].mem_cgroup = memcg;
+		head[i].memcg_data = (unsigned long)memcg;
 	}
 }
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
@@ -4664,7 +4655,7 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
 void mem_cgroup_track_foreign_dirty_slowpath(struct page *page,
 					     struct bdi_writeback *wb)
 {
-	struct mem_cgroup *memcg = page->mem_cgroup;
+	struct mem_cgroup *memcg = page_memcg(page);
 	struct memcg_cgwb_frn *frn;
 	u64 now = get_jiffies_64();
 	u64 oldest_at = now;
@@ -5641,14 +5632,14 @@ static int mem_cgroup_move_account(struct page *page,
 
 	/*
 	 * Prevent mem_cgroup_migrate() from looking at
-	 * page->mem_cgroup of its source page while we change it.
+	 * page's memory cgroup of its source page while we change it.
 	 */
 	ret = -EBUSY;
 	if (!trylock_page(page))
 		goto out;
 
 	ret = -EINVAL;
-	if (page->mem_cgroup != from)
+	if (page_memcg(page) != from)
 		goto out_unlock;
 
 	pgdat = page_pgdat(page);
@@ -5703,13 +5694,13 @@ static int mem_cgroup_move_account(struct page *page,
 	/*
 	 * All state has been migrated, let's switch to the new memcg.
 	 *
-	 * It is safe to change page->mem_cgroup here because the page
+	 * It is safe to change page's memcg here because the page
 	 * is referenced, charged, isolated, and locked: we can't race
 	 * with (un)charging, migration, LRU putback, or anything else
-	 * that would rely on a stable page->mem_cgroup.
+	 * that would rely on a stable page's memory cgroup.
 	 *
 	 * Note that lock_page_memcg is a memcg lock, not a page lock,
-	 * to save space. As soon as we switch page->mem_cgroup to a
+	 * to save space. As soon as we switch page's memory cgroup to a
 	 * new memcg that isn't locked, the above state can change
 	 * concurrently again. Make sure we're truly done with it.
 	 */
@@ -5718,7 +5709,7 @@ static int mem_cgroup_move_account(struct page *page,
 	css_get(&to->css);
 	css_put(&from->css);
 
-	page->mem_cgroup = to;
+	page->memcg_data = (unsigned long)to;
 
 	__unlock_page_memcg(from);
 
@@ -5784,7 +5775,7 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
 		 * mem_cgroup_move_account() checks the page is valid or
 		 * not under LRU exclusion.
 		 */
-		if (page->mem_cgroup == mc.from) {
+		if (page_memcg(page) == mc.from) {
 			ret = MC_TARGET_PAGE;
 			if (is_device_private_page(page))
 				ret = MC_TARGET_DEVICE;
@@ -5828,7 +5819,7 @@ static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
 	VM_BUG_ON_PAGE(!page || !PageHead(page), page);
 	if (!(mc.flags & MOVE_ANON))
 		return ret;
-	if (page->mem_cgroup == mc.from) {
+	if (page_memcg(page) == mc.from) {
 		ret = MC_TARGET_PAGE;
 		if (target) {
 			get_page(page);
@@ -6774,12 +6765,12 @@ int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
 		/*
 		 * Every swap fault against a single page tries to charge the
 		 * page, bail as early as possible.  shmem_unuse() encounters
-		 * already charged pages, too.  page->mem_cgroup is protected
-		 * by the page lock, which serializes swap cache removal, which
-		 * in turn serializes uncharging.
+		 * already charged pages, too.  page and memcg binding is
+		 * protected by the page lock, which serializes swap cache
+		 * removal, which in turn serializes uncharging.
 		 */
 		VM_BUG_ON_PAGE(!PageLocked(page), page);
-		if (compound_head(page)->mem_cgroup)
+		if (page_memcg(compound_head(page)))
 			goto out;
 
 		id = lookup_swap_cgroup_id(ent);
@@ -6863,21 +6854,21 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
 
 	VM_BUG_ON_PAGE(PageLRU(page), page);
 
-	if (!page->mem_cgroup)
+	if (!page_memcg(page))
 		return;
 
 	/*
 	 * Nobody should be changing or seriously looking at
-	 * page->mem_cgroup at this point, we have fully
+	 * page_memcg(page) at this point, we have fully
 	 * exclusive access to the page.
 	 */
 
-	if (ug->memcg != page->mem_cgroup) {
+	if (ug->memcg != page_memcg(page)) {
 		if (ug->memcg) {
 			uncharge_batch(ug);
 			uncharge_gather_clear(ug);
 		}
-		ug->memcg = page->mem_cgroup;
+		ug->memcg = page_memcg(page);
 
 		/* pairs with css_put in uncharge_batch */
 		css_get(&ug->memcg->css);
@@ -6894,7 +6885,7 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
 	}
 
 	ug->dummy_page = page;
-	page->mem_cgroup = NULL;
+	page->memcg_data = 0;
 	css_put(&ug->memcg->css);
 }
 
@@ -6937,7 +6928,7 @@ void mem_cgroup_uncharge(struct page *page)
 		return;
 
 	/* Don't touch page->lru of any random page, pre-check: */
-	if (!page->mem_cgroup)
+	if (!page_memcg(page))
 		return;
 
 	uncharge_gather_clear(&ug);
@@ -6987,11 +6978,11 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
 		return;
 
 	/* Page cache replacement: new page already charged? */
-	if (newpage->mem_cgroup)
+	if (page_memcg(newpage))
 		return;
 
 	/* Swapcache readahead pages can get replaced before being charged */
-	memcg = oldpage->mem_cgroup;
+	memcg = page_memcg(oldpage);
 	if (!memcg)
 		return;
 
@@ -7186,7 +7177,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		return;
 
-	memcg = page->mem_cgroup;
+	memcg = page_memcg(page);
 
 	/* Readahead page, never charged */
 	if (!memcg)
@@ -7207,7 +7198,7 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	VM_BUG_ON_PAGE(oldid, page);
 	mod_memcg_state(swap_memcg, MEMCG_SWAP, nr_entries);
 
-	page->mem_cgroup = NULL;
+	page->memcg_data = 0;
 
 	if (!mem_cgroup_is_root(memcg))
 		page_counter_uncharge(&memcg->memory, nr_entries);
@@ -7250,7 +7241,7 @@ int mem_cgroup_try_charge_swap(struct page *page, swp_entry_t entry)
 	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		return 0;
 
-	memcg = page->mem_cgroup;
+	memcg = page_memcg(page);
 
 	/* Readahead page, never charged */
 	if (!memcg)
@@ -7331,7 +7322,7 @@ bool mem_cgroup_swap_full(struct page *page)
 	if (cgroup_memory_noswap || !cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		return false;
 
-	memcg = page->mem_cgroup;
+	memcg = page_memcg(page);
 	if (!memcg)
 		return false;
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 23f5066bd4a5..271133b8243b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1092,7 +1092,7 @@ static inline bool page_expected_state(struct page *page,
 	if (unlikely((unsigned long)page->mapping |
 			page_ref_count(page) |
 #ifdef CONFIG_MEMCG
-			(unsigned long)page->mem_cgroup |
+			(unsigned long)page_memcg(page) |
 #endif
 			(page->flags & check_flags)))
 		return false;
@@ -1117,7 +1117,7 @@ static const char *page_bad_reason(struct page *page, unsigned long flags)
 			bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
 	}
 #ifdef CONFIG_MEMCG
-	if (unlikely(page->mem_cgroup))
+	if (unlikely(page_memcg(page)))
 		bad_reason = "page still charged to cgroup";
 #endif
 	return bad_reason;
diff --git a/mm/page_io.c b/mm/page_io.c
index 433df1263349..9bca17ecc4df 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -291,12 +291,14 @@ static inline void count_swpout_vm_event(struct page *page)
 static void bio_associate_blkg_from_page(struct bio *bio, struct page *page)
 {
 	struct cgroup_subsys_state *css;
+	struct mem_cgroup *memcg;
 
-	if (!page->mem_cgroup)
+	memcg = page_memcg(page);
+	if (!memcg)
 		return;
 
 	rcu_read_lock();
-	css = cgroup_e_css(page->mem_cgroup->css.cgroup, &io_cgrp_subsys);
+	css = cgroup_e_css(memcg->css.cgroup, &io_cgrp_subsys);
 	bio_associate_blkg_from_css(bio, css);
 	rcu_read_unlock();
 }
diff --git a/mm/slab.h b/mm/slab.h
index 6d7c6a5056ba..e2535cee0d33 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -242,18 +242,17 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla
 static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
 {
 	/*
-	 * page->mem_cgroup and page->obj_cgroups are sharing the same
+	 * Page's memory cgroup and obj_cgroups vector are sharing the same
 	 * space. To distinguish between them in case we don't know for sure
 	 * that the page is a slab page (e.g. page_cgroup_ino()), let's
 	 * always set the lowest bit of obj_cgroups.
 	 */
-	return (struct obj_cgroup **)
-		((unsigned long)page->obj_cgroups & ~0x1UL);
+	return (struct obj_cgroup **)(page->memcg_data & ~0x1UL);
 }
 
 static inline bool page_has_obj_cgroups(struct page *page)
 {
-	return ((unsigned long)page->obj_cgroups & 0x1UL);
+	return page->memcg_data & 0x1UL;
 }
 
 int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
@@ -262,7 +261,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
 static inline void memcg_free_page_obj_cgroups(struct page *page)
 {
 	kfree(page_obj_cgroups(page));
-	page->obj_cgroups = NULL;
+	page->memcg_data = 0;
 }
 
 static inline size_t obj_full_size(struct kmem_cache *s)
diff --git a/mm/workingset.c b/mm/workingset.c
index 975a4d2dd02e..130348cbf40a 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -257,7 +257,7 @@ void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg)
 	struct lruvec *lruvec;
 	int memcgid;
 
-	/* Page is fully exclusive and pins page->mem_cgroup */
+	/* Page is fully exclusive and pins page's memory cgroup pointer */
 	VM_BUG_ON_PAGE(PageLRU(page), page);
 	VM_BUG_ON_PAGE(page_count(page), page);
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
-- 
2.26.2

[PATCH bpf-next v9 02/34] mm: memcontrol/slab: use helpers to access slab page's memcg_data

[Roman Gushchin]

To gather all direct accesses to struct page's memcg_data field in one
place, let's introduce 3 new helpers to use in the slab accounting code:

  struct obj_cgroup **page_objcgs(struct page *page);
  struct obj_cgroup **page_objcgs_check(struct page *page);
  bool set_page_objcgs(struct page *page, struct obj_cgroup **objcgs);

They are similar to the corresponding API for generic pages, except that
the setter can return false, indicating that the value has been already
set from a different thread.

Link: https://lkml.kernel.org/r/20201027001657.3398190-3-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/memcontrol.h | 64 ++++++++++++++++++++++++++++++++++++++
 mm/memcontrol.c            |  6 ++--
 mm/slab.h                  | 35 +++++----------------
 3 files changed, 75 insertions(+), 30 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index f95c1433461c..c7ac0a5b8989 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -416,6 +416,70 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
 	return (struct mem_cgroup *)memcg_data;
 }
 
+#ifdef CONFIG_MEMCG_KMEM
+/*
+ * page_objcgs - get the object cgroups vector associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the object cgroups vector associated with the page,
+ * or NULL. This function assumes that the page is known to have an
+ * associated object cgroups vector. It's not safe to call this function
+ * against pages, which might have an associated memory cgroup: e.g.
+ * kernel stack pages.
+ */
+static inline struct obj_cgroup **page_objcgs(struct page *page)
+{
+	return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL);
+}
+
+/*
+ * page_objcgs_check - get the object cgroups vector associated with a page
+ * @page: a pointer to the page struct
+ *
+ * Returns a pointer to the object cgroups vector associated with the page,
+ * or NULL. This function is safe to use if the page can be directly associated
+ * with a memory cgroup.
+ */
+static inline struct obj_cgroup **page_objcgs_check(struct page *page)
+{
+	unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+	if (memcg_data && (memcg_data & 0x1UL))
+		return (struct obj_cgroup **)(memcg_data & ~0x1UL);
+
+	return NULL;
+}
+
+/*
+ * set_page_objcgs - associate a page with a object cgroups vector
+ * @page: a pointer to the page struct
+ * @objcgs: a pointer to the object cgroups vector
+ *
+ * Atomically associates a page with a vector of object cgroups.
+ */
+static inline bool set_page_objcgs(struct page *page,
+					struct obj_cgroup **objcgs)
+{
+	return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL);
+}
+#else
+static inline struct obj_cgroup **page_objcgs(struct page *page)
+{
+	return NULL;
+}
+
+static inline struct obj_cgroup **page_objcgs_check(struct page *page)
+{
+	return NULL;
+}
+
+static inline bool set_page_objcgs(struct page *page,
+					struct obj_cgroup **objcgs)
+{
+	return true;
+}
+#endif
+
 static __always_inline bool memcg_stat_item_in_bytes(int idx)
 {
 	if (idx == MEMCG_PERCPU_B)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3968d68503cb..0054b4846770 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2899,7 +2899,7 @@ int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
 	if (!vec)
 		return -ENOMEM;
 
-	if (cmpxchg(&page->memcg_data, 0, (unsigned long)vec | 0x1UL))
+	if (!set_page_objcgs(page, vec))
 		kfree(vec);
 	else
 		kmemleak_not_leak(vec);
@@ -2933,12 +2933,12 @@ struct mem_cgroup *mem_cgroup_from_obj(void *p)
 	 * Memcg membership data for each individual object is saved in
 	 * the page->obj_cgroups.
 	 */
-	if (page_has_obj_cgroups(page)) {
+	if (page_objcgs_check(page)) {
 		struct obj_cgroup *objcg;
 		unsigned int off;
 
 		off = obj_to_index(page->slab_cache, page, p);
-		objcg = page_obj_cgroups(page)[off];
+		objcg = page_objcgs(page)[off];
 		if (objcg)
 			return obj_cgroup_memcg(objcg);
 
diff --git a/mm/slab.h b/mm/slab.h
index e2535cee0d33..9a54a0cb5cca 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -239,28 +239,12 @@ static inline bool kmem_cache_debug_flags(struct kmem_cache *s, slab_flags_t fla
 }
 
 #ifdef CONFIG_MEMCG_KMEM
-static inline struct obj_cgroup **page_obj_cgroups(struct page *page)
-{
-	/*
-	 * Page's memory cgroup and obj_cgroups vector are sharing the same
-	 * space. To distinguish between them in case we don't know for sure
-	 * that the page is a slab page (e.g. page_cgroup_ino()), let's
-	 * always set the lowest bit of obj_cgroups.
-	 */
-	return (struct obj_cgroup **)(page->memcg_data & ~0x1UL);
-}
-
-static inline bool page_has_obj_cgroups(struct page *page)
-{
-	return page->memcg_data & 0x1UL;
-}
-
 int memcg_alloc_page_obj_cgroups(struct page *page, struct kmem_cache *s,
 				 gfp_t gfp);
 
 static inline void memcg_free_page_obj_cgroups(struct page *page)
 {
-	kfree(page_obj_cgroups(page));
+	kfree(page_objcgs(page));
 	page->memcg_data = 0;
 }
 
@@ -322,7 +306,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
 		if (likely(p[i])) {
 			page = virt_to_head_page(p[i]);
 
-			if (!page_has_obj_cgroups(page) &&
+			if (!page_objcgs(page) &&
 			    memcg_alloc_page_obj_cgroups(page, s, flags)) {
 				obj_cgroup_uncharge(objcg, obj_full_size(s));
 				continue;
@@ -330,7 +314,7 @@ static inline void memcg_slab_post_alloc_hook(struct kmem_cache *s,
 
 			off = obj_to_index(s, page, p[i]);
 			obj_cgroup_get(objcg);
-			page_obj_cgroups(page)[off] = objcg;
+			page_objcgs(page)[off] = objcg;
 			mod_objcg_state(objcg, page_pgdat(page),
 					cache_vmstat_idx(s), obj_full_size(s));
 		} else {
@@ -344,6 +328,7 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
 					void **p, int objects)
 {
 	struct kmem_cache *s;
+	struct obj_cgroup **objcgs;
 	struct obj_cgroup *objcg;
 	struct page *page;
 	unsigned int off;
@@ -357,7 +342,8 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
 			continue;
 
 		page = virt_to_head_page(p[i]);
-		if (!page_has_obj_cgroups(page))
+		objcgs = page_objcgs(page);
+		if (!objcgs)
 			continue;
 
 		if (!s_orig)
@@ -366,11 +352,11 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
 			s = s_orig;
 
 		off = obj_to_index(s, page, p[i]);
-		objcg = page_obj_cgroups(page)[off];
+		objcg = objcgs[off];
 		if (!objcg)
 			continue;
 
-		page_obj_cgroups(page)[off] = NULL;
+		objcgs[off] = NULL;
 		obj_cgroup_uncharge(objcg, obj_full_size(s));
 		mod_objcg_state(objcg, page_pgdat(page), cache_vmstat_idx(s),
 				-obj_full_size(s));
@@ -379,11 +365,6 @@ static inline void memcg_slab_free_hook(struct kmem_cache *s_orig,
 }
 
 #else /* CONFIG_MEMCG_KMEM */
-static inline bool page_has_obj_cgroups(struct page *page)
-{
-	return false;
-}
-
 static inline struct mem_cgroup *memcg_from_slab_obj(void *ptr)
 {
 	return NULL;
-- 
2.26.2

[PATCH bpf-next v9 03/34] mm: introduce page memcg flags

[Roman Gushchin]

The lowest bit in page->memcg_data is used to distinguish between struct
memory_cgroup pointer and a pointer to a objcgs array.  All checks and
modifications of this bit are open-coded.

Let's formalize it using page memcg flags, defined in enum
page_memcg_data_flags.

Additional flags might be added later.

Link: https://lkml.kernel.org/r/20201027001657.3398190-4-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/memcontrol.h | 32 ++++++++++++++++++++------------
 1 file changed, 20 insertions(+), 12 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index c7ac0a5b8989..99a4841d658b 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -343,6 +343,15 @@ struct mem_cgroup {
 
 extern struct mem_cgroup *root_mem_cgroup;
 
+enum page_memcg_data_flags {
+	/* page->memcg_data is a pointer to an objcgs vector */
+	MEMCG_DATA_OBJCGS = (1UL << 0),
+	/* the next bit after the last actual flag */
+	__NR_MEMCG_DATA_FLAGS  = (1UL << 1),
+};
+
+#define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1)
+
 /*
  * page_memcg - get the memory cgroup associated with a page
  * @page: a pointer to the page struct
@@ -404,13 +413,7 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
 	 */
 	unsigned long memcg_data = READ_ONCE(page->memcg_data);
 
-	/*
-	 * The lowest bit set means that memcg isn't a valid
-	 * memcg pointer, but a obj_cgroups pointer.
-	 * In this case the page is shared and doesn't belong
-	 * to any specific memory cgroup.
-	 */
-	if (memcg_data & 0x1UL)
+	if (memcg_data & MEMCG_DATA_OBJCGS)
 		return NULL;
 
 	return (struct mem_cgroup *)memcg_data;
@@ -429,7 +432,11 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
  */
 static inline struct obj_cgroup **page_objcgs(struct page *page)
 {
-	return (struct obj_cgroup **)(READ_ONCE(page->memcg_data) & ~0x1UL);
+	unsigned long memcg_data = READ_ONCE(page->memcg_data);
+
+	VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), page);
+
+	return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
@@ -444,10 +451,10 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page)
 {
 	unsigned long memcg_data = READ_ONCE(page->memcg_data);
 
-	if (memcg_data && (memcg_data & 0x1UL))
-		return (struct obj_cgroup **)(memcg_data & ~0x1UL);
+	if (!memcg_data || !(memcg_data & MEMCG_DATA_OBJCGS))
+		return NULL;
 
-	return NULL;
+	return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
@@ -460,7 +467,8 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page)
 static inline bool set_page_objcgs(struct page *page,
 					struct obj_cgroup **objcgs)
 {
-	return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs | 0x1UL);
+	return !cmpxchg(&page->memcg_data, 0, (unsigned long)objcgs |
+			MEMCG_DATA_OBJCGS);
 }
 #else
 static inline struct obj_cgroup **page_objcgs(struct page *page)
-- 
2.26.2

[PATCH bpf-next v9 04/34] mm: convert page kmemcg type to a page memcg flag

[Roman Gushchin]

PageKmemcg flag is currently defined as a page type (like buddy, offline,
table and guard).  Semantically it means that the page was accounted as a
kernel memory by the page allocator and has to be uncharged on the
release.

As a side effect of defining the flag as a page type, the accounted page
can't be mapped to userspace (look at page_has_type() and comments above).
In particular, this blocks the accounting of vmalloc-backed memory used
by some bpf maps, because these maps do map the memory to userspace.

One option is to fix it by complicating the access to page->mapcount,
which provides some free bits for page->page_type.

But it's way better to move this flag into page->memcg_data flags.
Indeed, the flag makes no sense without enabled memory cgroups and memory
cgroup pointer set in particular.

This commit replaces PageKmemcg() and __SetPageKmemcg() with
PageMemcgKmem() and an open-coded OR operation setting the memcg pointer
with the MEMCG_DATA_KMEM bit.  __ClearPageKmemcg() can be simple deleted,
as the whole memcg_data is zeroed at once.

As a bonus, on !CONFIG_MEMCG build the PageMemcgKmem() check will be
compiled out.

Link: https://lkml.kernel.org/r/20201027001657.3398190-5-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/memcontrol.h | 37 +++++++++++++++++++++++++++++++++----
 include/linux/page-flags.h | 11 ++---------
 mm/memcontrol.c            | 16 +++++-----------
 mm/page_alloc.c            |  4 ++--
 4 files changed, 42 insertions(+), 26 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 99a4841d658b..7c9d43476166 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -346,8 +346,10 @@ extern struct mem_cgroup *root_mem_cgroup;
 enum page_memcg_data_flags {
 	/* page->memcg_data is a pointer to an objcgs vector */
 	MEMCG_DATA_OBJCGS = (1UL << 0),
+	/* page has been accounted as a non-slab kernel page */
+	MEMCG_DATA_KMEM = (1UL << 1),
 	/* the next bit after the last actual flag */
-	__NR_MEMCG_DATA_FLAGS  = (1UL << 1),
+	__NR_MEMCG_DATA_FLAGS  = (1UL << 2),
 };
 
 #define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1)
@@ -369,8 +371,12 @@ enum page_memcg_data_flags {
  */
 static inline struct mem_cgroup *page_memcg(struct page *page)
 {
+	unsigned long memcg_data = page->memcg_data;
+
 	VM_BUG_ON_PAGE(PageSlab(page), page);
-	return (struct mem_cgroup *)page->memcg_data;
+	VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_OBJCGS, page);
+
+	return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
@@ -387,7 +393,8 @@ static inline struct mem_cgroup *page_memcg_rcu(struct page *page)
 	VM_BUG_ON_PAGE(PageSlab(page), page);
 	WARN_ON_ONCE(!rcu_read_lock_held());
 
-	return (struct mem_cgroup *)READ_ONCE(page->memcg_data);
+	return (struct mem_cgroup *)(READ_ONCE(page->memcg_data) &
+				     ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
@@ -416,7 +423,21 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
 	if (memcg_data & MEMCG_DATA_OBJCGS)
 		return NULL;
 
-	return (struct mem_cgroup *)memcg_data;
+	return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
+}
+
+/*
+ * PageMemcgKmem - check if the page has MemcgKmem flag set
+ * @page: a pointer to the page struct
+ *
+ * Checks if the page has MemcgKmem flag set. The caller must ensure that
+ * the page has an associated memory cgroup. It's not safe to call this function
+ * against some types of pages, e.g. slab pages.
+ */
+static inline bool PageMemcgKmem(struct page *page)
+{
+	VM_BUG_ON_PAGE(page->memcg_data & MEMCG_DATA_OBJCGS, page);
+	return page->memcg_data & MEMCG_DATA_KMEM;
 }
 
 #ifdef CONFIG_MEMCG_KMEM
@@ -435,6 +456,7 @@ static inline struct obj_cgroup **page_objcgs(struct page *page)
 	unsigned long memcg_data = READ_ONCE(page->memcg_data);
 
 	VM_BUG_ON_PAGE(memcg_data && !(memcg_data & MEMCG_DATA_OBJCGS), page);
+	VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, page);
 
 	return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
@@ -454,6 +476,8 @@ static inline struct obj_cgroup **page_objcgs_check(struct page *page)
 	if (!memcg_data || !(memcg_data & MEMCG_DATA_OBJCGS))
 		return NULL;
 
+	VM_BUG_ON_PAGE(memcg_data & MEMCG_DATA_KMEM, page);
+
 	return (struct obj_cgroup **)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
@@ -1109,6 +1133,11 @@ static inline struct mem_cgroup *page_memcg_check(struct page *page)
 	return NULL;
 }
 
+static inline bool PageMemcgKmem(struct page *page)
+{
+	return false;
+}
+
 static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
 {
 	return true;
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 4f6ba9379112..fc0e1bd48e73 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -715,9 +715,8 @@ PAGEFLAG_FALSE(DoubleMap)
 #define PAGE_MAPCOUNT_RESERVE	-128
 #define PG_buddy	0x00000080
 #define PG_offline	0x00000100
-#define PG_kmemcg	0x00000200
-#define PG_table	0x00000400
-#define PG_guard	0x00000800
+#define PG_table	0x00000200
+#define PG_guard	0x00000400
 
 #define PageType(page, flag)						\
 	((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE)
@@ -768,12 +767,6 @@ PAGE_TYPE_OPS(Buddy, buddy)
  */
 PAGE_TYPE_OPS(Offline, offline)
 
-/*
- * If kmemcg is enabled, the buddy allocator will set PageKmemcg() on
- * pages allocated with __GFP_ACCOUNT. It gets cleared on page free.
- */
-PAGE_TYPE_OPS(Kmemcg, kmemcg)
-
 /*
  * Marks pages in use as page tables.
  */
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 0054b4846770..e0366e306221 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3090,8 +3090,8 @@ int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order)
 	if (memcg && !mem_cgroup_is_root(memcg)) {
 		ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
 		if (!ret) {
-			page->memcg_data = (unsigned long)memcg;
-			__SetPageKmemcg(page);
+			page->memcg_data = (unsigned long)memcg |
+				MEMCG_DATA_KMEM;
 			return 0;
 		}
 		css_put(&memcg->css);
@@ -3116,10 +3116,6 @@ void __memcg_kmem_uncharge_page(struct page *page, int order)
 	__memcg_kmem_uncharge(memcg, nr_pages);
 	page->memcg_data = 0;
 	css_put(&memcg->css);
-
-	/* slab pages do not have PageKmemcg flag set */
-	if (PageKmemcg(page))
-		__ClearPageKmemcg(page);
 }
 
 static bool consume_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes)
@@ -6877,12 +6873,10 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
 	nr_pages = compound_nr(page);
 	ug->nr_pages += nr_pages;
 
-	if (!PageKmemcg(page)) {
-		ug->pgpgout++;
-	} else {
+	if (PageMemcgKmem(page))
 		ug->nr_kmem += nr_pages;
-		__ClearPageKmemcg(page);
-	}
+	else
+		ug->pgpgout++;
 
 	ug->dummy_page = page;
 	page->memcg_data = 0;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 271133b8243b..3c53018c9c61 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1214,7 +1214,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
 		 * Do not let hwpoison pages hit pcplists/buddy
 		 * Untie memcg state and reset page's owner
 		 */
-		if (memcg_kmem_enabled() && PageKmemcg(page))
+		if (memcg_kmem_enabled() && PageMemcgKmem(page))
 			__memcg_kmem_uncharge_page(page, order);
 		reset_page_owner(page, order);
 		return false;
@@ -1244,7 +1244,7 @@ static __always_inline bool free_pages_prepare(struct page *page,
 	}
 	if (PageMappingFlags(page))
 		page->mapping = NULL;
-	if (memcg_kmem_enabled() && PageKmemcg(page))
+	if (memcg_kmem_enabled() && PageMemcgKmem(page))
 		__memcg_kmem_uncharge_page(page, order);
 	if (check_free)
 		bad += check_free_page(page);
-- 
2.26.2

[PATCH bpf-next v9 05/34] bpf: memcg-based memory accounting for bpf progs

[Roman Gushchin]

Include memory used by bpf programs into the memcg-based accounting.
This includes the memory used by programs itself, auxiliary data,
statistics and bpf line info. A memory cgroup containing the
process which loads the program is getting charged.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/core.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index ff55cbcfbab4..2921f58c03a8 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -77,7 +77,7 @@ void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, uns
 
 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags)
 {
-	gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+	gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
 	struct bpf_prog_aux *aux;
 	struct bpf_prog *fp;
 
@@ -86,7 +86,7 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag
 	if (fp == NULL)
 		return NULL;
 
-	aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
+	aux = kzalloc(sizeof(*aux), GFP_KERNEL_ACCOUNT | gfp_extra_flags);
 	if (aux == NULL) {
 		vfree(fp);
 		return NULL;
@@ -106,7 +106,7 @@ struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flag
 
 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
 {
-	gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+	gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
 	struct bpf_prog *prog;
 	int cpu;
 
@@ -138,7 +138,7 @@ int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog)
 
 	prog->aux->jited_linfo = kcalloc(prog->aux->nr_linfo,
 					 sizeof(*prog->aux->jited_linfo),
-					 GFP_KERNEL | __GFP_NOWARN);
+					 GFP_KERNEL_ACCOUNT | __GFP_NOWARN);
 	if (!prog->aux->jited_linfo)
 		return -ENOMEM;
 
@@ -219,7 +219,7 @@ void bpf_prog_free_linfo(struct bpf_prog *prog)
 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 				  gfp_t gfp_extra_flags)
 {
-	gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
+	gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
 	struct bpf_prog *fp;
 	u32 pages, delta;
 	int ret;
-- 
2.26.2

[PATCH bpf-next v9 06/34] bpf: prepare for memcg-based memory accounting for bpf maps

[Roman Gushchin]

Bpf maps can be updated from an interrupt context and in such
case there is no process which can be charged. It makes the memory
accounting of bpf maps non-trivial.

Fortunately, after commit 4127c6504f25 ("mm: kmem: enable kernel
memcg accounting from interrupt contexts") and commit b87d8cefe43c
("mm, memcg: rework remote charging API to support nesting")
it's finally possible.

To make the ownership model simple and consistent, when the map
is created, the memory cgroup of the current process is recorded.
All subsequent allocations related to the bpf map are charged to
the same memory cgroup. It includes allocations made by any processes
(even if they do belong to a different cgroup) and from interrupts.

This commit introduces 3 new helpers, which will be used by following
commits to enable the accounting of bpf maps memory:
  - bpf_map_kmalloc_node()
  - bpf_map_kzalloc()
  - bpf_map_alloc_percpu()

They are wrapping popular memory allocation functions. They set
the active memory cgroup to the map's memory cgroup and add
__GFP_ACCOUNT to the passed gfp flags. Then they call into
the corresponding memory allocation function and restore
the original active memory cgroup.

These helpers are supposed to use everywhere except the map creation
path. During the map creation when the map structure is allocated by
itself, it cannot be passed to those helpers. In those cases default
memory allocation function will be used with the __GFP_ACCOUNT flag.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 include/linux/bpf.h  | 34 ++++++++++++++++++++++++
 kernel/bpf/syscall.c | 63 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 97 insertions(+)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e1bcb6d7345c..e1f2c95c15ec 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -20,6 +20,8 @@
 #include <linux/module.h>
 #include <linux/kallsyms.h>
 #include <linux/capability.h>
+#include <linux/sched/mm.h>
+#include <linux/slab.h>
 
 struct bpf_verifier_env;
 struct bpf_verifier_log;
@@ -37,6 +39,7 @@ struct bpf_iter_aux_info;
 struct bpf_local_storage;
 struct bpf_local_storage_map;
 struct kobject;
+struct mem_cgroup;
 
 extern struct idr btf_idr;
 extern spinlock_t btf_idr_lock;
@@ -161,6 +164,9 @@ struct bpf_map {
 	u32 btf_value_type_id;
 	struct btf *btf;
 	struct bpf_map_memory memory;
+#ifdef CONFIG_MEMCG_KMEM
+	struct mem_cgroup *memcg;
+#endif
 	char name[BPF_OBJ_NAME_LEN];
 	u32 btf_vmlinux_value_type_id;
 	bool bypass_spec_v1;
@@ -1240,6 +1246,34 @@ int  generic_map_delete_batch(struct bpf_map *map,
 struct bpf_map *bpf_map_get_curr_or_next(u32 *id);
 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id);
 
+#ifdef CONFIG_MEMCG_KMEM
+void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+			   int node);
+void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags);
+void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
+				    size_t align, gfp_t flags);
+#else
+static inline void *
+bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+		     int node)
+{
+	return kmalloc_node(size, flags, node);
+}
+
+static inline void *
+bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
+{
+	return kzalloc(size, flags);
+}
+
+static inline void __percpu *
+bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, size_t align,
+		     gfp_t flags)
+{
+	return __alloc_percpu_gfp(size, align, flags);
+}
+#endif
+
 extern int sysctl_unprivileged_bpf_disabled;
 
 static inline bool bpf_allow_ptr_leaks(void)
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index f3fe9f53f93c..dedbf6d4cd84 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -31,6 +31,7 @@
 #include <linux/poll.h>
 #include <linux/bpf-netns.h>
 #include <linux/rcupdate_trace.h>
+#include <linux/memcontrol.h>
 
 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
@@ -456,6 +457,65 @@ void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
 		__release(&map_idr_lock);
 }
 
+#ifdef CONFIG_MEMCG_KMEM
+static void bpf_map_save_memcg(struct bpf_map *map)
+{
+	map->memcg = get_mem_cgroup_from_mm(current->mm);
+}
+
+static void bpf_map_release_memcg(struct bpf_map *map)
+{
+	mem_cgroup_put(map->memcg);
+}
+
+void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
+			   int node)
+{
+	struct mem_cgroup *old_memcg;
+	void *ptr;
+
+	old_memcg = set_active_memcg(map->memcg);
+	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
+	set_active_memcg(old_memcg);
+
+	return ptr;
+}
+
+void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
+{
+	struct mem_cgroup *old_memcg;
+	void *ptr;
+
+	old_memcg = set_active_memcg(map->memcg);
+	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
+	set_active_memcg(old_memcg);
+
+	return ptr;
+}
+
+void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
+				    size_t align, gfp_t flags)
+{
+	struct mem_cgroup *old_memcg;
+	void __percpu *ptr;
+
+	old_memcg = set_active_memcg(map->memcg);
+	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
+	set_active_memcg(old_memcg);
+
+	return ptr;
+}
+
+#else
+static void bpf_map_save_memcg(struct bpf_map *map)
+{
+}
+
+static void bpf_map_release_memcg(struct bpf_map *map)
+{
+}
+#endif
+
 /* called from workqueue */
 static void bpf_map_free_deferred(struct work_struct *work)
 {
@@ -464,6 +524,7 @@ static void bpf_map_free_deferred(struct work_struct *work)
 
 	bpf_map_charge_move(&mem, &map->memory);
 	security_bpf_map_free(map);
+	bpf_map_release_memcg(map);
 	/* implementation dependent freeing */
 	map->ops->map_free(map);
 	bpf_map_charge_finish(&mem);
@@ -875,6 +936,8 @@ static int map_create(union bpf_attr *attr)
 	if (err)
 		goto free_map_sec;
 
+	bpf_map_save_memcg(map);
+
 	err = bpf_map_new_fd(map, f_flags);
 	if (err < 0) {
 		/* failed to allocate fd.
-- 
2.26.2

[PATCH bpf-next v9 07/34] bpf: memcg-based memory accounting for bpf maps

[Roman Gushchin]

This patch enables memcg-based memory accounting for memory allocated
by __bpf_map_area_alloc(), which is used by many types of bpf maps for
large initial memory allocations.

Please note, that __bpf_map_area_alloc() should not be used outside of
map creation paths without setting the active memory cgroup to the
map's memory cgroup.

Following patches in the series will refine the accounting for
some of the map types.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/syscall.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index dedbf6d4cd84..dff3a5f62d7a 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -268,6 +268,10 @@ static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
 	return err;
 }
 
+/* Please, do not use this function outside from the map creation path
+ * (e.g. in map update path) without taking care of setting the active
+ * memory cgroup (see at bpf_map_kmalloc_node() for example).
+ */
 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
 {
 	/* We really just want to fail instead of triggering OOM killer
@@ -280,7 +284,7 @@ static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
 	 */
 
-	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO;
+	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
 	unsigned int flags = 0;
 	unsigned long align = 1;
 	void *area;
-- 
2.26.2

[PATCH bpf-next v9 08/34] bpf: refine memcg-based memory accounting for arraymap maps

[Roman Gushchin]

Include percpu arrays and auxiliary data into the memcg-based memory
accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/arraymap.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index c6c81eceb68f..d837e0603c89 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -34,8 +34,8 @@ static int bpf_array_alloc_percpu(struct bpf_array *array)
 	int i;
 
 	for (i = 0; i < array->map.max_entries; i++) {
-		ptr = __alloc_percpu_gfp(array->elem_size, 8,
-					 GFP_USER | __GFP_NOWARN);
+		ptr = bpf_map_alloc_percpu(&array->map, array->elem_size, 8,
+					   GFP_USER | __GFP_NOWARN);
 		if (!ptr) {
 			bpf_array_free_percpu(array);
 			return -ENOMEM;
@@ -1018,7 +1018,7 @@ static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr)
 	struct bpf_array_aux *aux;
 	struct bpf_map *map;
 
-	aux = kzalloc(sizeof(*aux), GFP_KERNEL);
+	aux = kzalloc(sizeof(*aux), GFP_KERNEL_ACCOUNT);
 	if (!aux)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.26.2

[PATCH bpf-next v9 09/34] bpf: refine memcg-based memory accounting for cpumap maps

[Roman Gushchin]

Include metadata and percpu data into the memcg-based memory
accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/cpumap.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index c61a23b564aa..90b949666605 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -97,7 +97,7 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
 	    attr->map_flags & ~BPF_F_NUMA_NODE)
 		return ERR_PTR(-EINVAL);
 
-	cmap = kzalloc(sizeof(*cmap), GFP_USER);
+	cmap = kzalloc(sizeof(*cmap), GFP_USER | __GFP_ACCOUNT);
 	if (!cmap)
 		return ERR_PTR(-ENOMEM);
 
@@ -412,7 +412,8 @@ static int __cpu_map_load_bpf_program(struct bpf_cpu_map_entry *rcpu, int fd)
 }
 
 static struct bpf_cpu_map_entry *
-__cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
+__cpu_map_entry_alloc(struct bpf_map *map, struct bpf_cpumap_val *value,
+		      u32 cpu)
 {
 	int numa, err, i, fd = value->bpf_prog.fd;
 	gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
@@ -422,13 +423,13 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
 	/* Have map->numa_node, but choose node of redirect target CPU */
 	numa = cpu_to_node(cpu);
 
-	rcpu = kzalloc_node(sizeof(*rcpu), gfp, numa);
+	rcpu = bpf_map_kmalloc_node(map, sizeof(*rcpu), gfp | __GFP_ZERO, numa);
 	if (!rcpu)
 		return NULL;
 
 	/* Alloc percpu bulkq */
-	rcpu->bulkq = __alloc_percpu_gfp(sizeof(*rcpu->bulkq),
-					 sizeof(void *), gfp);
+	rcpu->bulkq = bpf_map_alloc_percpu(map, sizeof(*rcpu->bulkq),
+					   sizeof(void *), gfp);
 	if (!rcpu->bulkq)
 		goto free_rcu;
 
@@ -438,7 +439,8 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
 	}
 
 	/* Alloc queue */
-	rcpu->queue = kzalloc_node(sizeof(*rcpu->queue), gfp, numa);
+	rcpu->queue = bpf_map_kmalloc_node(map, sizeof(*rcpu->queue), gfp,
+					   numa);
 	if (!rcpu->queue)
 		goto free_bulkq;
 
@@ -447,7 +449,7 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
 		goto free_queue;
 
 	rcpu->cpu    = cpu;
-	rcpu->map_id = map_id;
+	rcpu->map_id = map->id;
 	rcpu->value.qsize  = value->qsize;
 
 	if (fd > 0 && __cpu_map_load_bpf_program(rcpu, fd))
@@ -455,7 +457,8 @@ __cpu_map_entry_alloc(struct bpf_cpumap_val *value, u32 cpu, int map_id)
 
 	/* Setup kthread */
 	rcpu->kthread = kthread_create_on_node(cpu_map_kthread_run, rcpu, numa,
-					       "cpumap/%d/map:%d", cpu, map_id);
+					       "cpumap/%d/map:%d", cpu,
+					       map->id);
 	if (IS_ERR(rcpu->kthread))
 		goto free_prog;
 
@@ -571,7 +574,7 @@ static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value,
 		rcpu = NULL; /* Same as deleting */
 	} else {
 		/* Updating qsize cause re-allocation of bpf_cpu_map_entry */
-		rcpu = __cpu_map_entry_alloc(&cpumap_value, key_cpu, map->id);
+		rcpu = __cpu_map_entry_alloc(map, &cpumap_value, key_cpu);
 		if (!rcpu)
 			return -ENOMEM;
 		rcpu->cmap = cmap;
-- 
2.26.2

[PATCH bpf-next v9 10/34] bpf: memcg-based memory accounting for cgroup storage maps

[Roman Gushchin]

Account memory used by cgroup storage maps including metadata
structures.

Account the percpu memory for the percpu flavor of cgroup storage.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/local_storage.c | 23 +++++++++++------------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 571bb351ed3b..74dcee8926e5 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -164,10 +164,10 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *key,
 		return 0;
 	}
 
-	new = kmalloc_node(sizeof(struct bpf_storage_buffer) +
-			   map->value_size,
-			   __GFP_ZERO | GFP_ATOMIC | __GFP_NOWARN,
-			   map->numa_node);
+	new = bpf_map_kmalloc_node(map, sizeof(struct bpf_storage_buffer) +
+				   map->value_size,
+				   __GFP_ZERO | GFP_ATOMIC | __GFP_NOWARN,
+				   map->numa_node);
 	if (!new)
 		return -ENOMEM;
 
@@ -313,7 +313,7 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
 		return ERR_PTR(ret);
 
 	map = kmalloc_node(sizeof(struct bpf_cgroup_storage_map),
-			   __GFP_ZERO | GFP_USER, numa_node);
+			   __GFP_ZERO | GFP_USER | __GFP_ACCOUNT, numa_node);
 	if (!map) {
 		bpf_map_charge_finish(&mem);
 		return ERR_PTR(-ENOMEM);
@@ -496,9 +496,9 @@ static size_t bpf_cgroup_storage_calculate_size(struct bpf_map *map, u32 *pages)
 struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 					enum bpf_cgroup_storage_type stype)
 {
+	const gfp_t gfp = __GFP_ZERO | GFP_USER;
 	struct bpf_cgroup_storage *storage;
 	struct bpf_map *map;
-	gfp_t flags;
 	size_t size;
 	u32 pages;
 
@@ -511,20 +511,19 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 	if (bpf_map_charge_memlock(map, pages))
 		return ERR_PTR(-EPERM);
 
-	storage = kmalloc_node(sizeof(struct bpf_cgroup_storage),
-			       __GFP_ZERO | GFP_USER, map->numa_node);
+	storage = bpf_map_kmalloc_node(map, sizeof(struct bpf_cgroup_storage),
+				       gfp, map->numa_node);
 	if (!storage)
 		goto enomem;
 
-	flags = __GFP_ZERO | GFP_USER;
-
 	if (stype == BPF_CGROUP_STORAGE_SHARED) {
-		storage->buf = kmalloc_node(size, flags, map->numa_node);
+		storage->buf = bpf_map_kmalloc_node(map, size, gfp,
+						    map->numa_node);
 		if (!storage->buf)
 			goto enomem;
 		check_and_init_map_lock(map, storage->buf->data);
 	} else {
-		storage->percpu_buf = __alloc_percpu_gfp(size, 8, flags);
+		storage->percpu_buf = bpf_map_alloc_percpu(map, size, 8, gfp);
 		if (!storage->percpu_buf)
 			goto enomem;
 	}
-- 
2.26.2

[PATCH bpf-next v9 11/34] bpf: refine memcg-based memory accounting for devmap maps

[Roman Gushchin]

Include map metadata and the node size (struct bpf_dtab_netdev)
into the accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/devmap.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 2b5ca93c17de..b43ab247302d 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -175,7 +175,7 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
 	if (!capable(CAP_NET_ADMIN))
 		return ERR_PTR(-EPERM);
 
-	dtab = kzalloc(sizeof(*dtab), GFP_USER);
+	dtab = kzalloc(sizeof(*dtab), GFP_USER | __GFP_ACCOUNT);
 	if (!dtab)
 		return ERR_PTR(-ENOMEM);
 
@@ -602,8 +602,9 @@ static struct bpf_dtab_netdev *__dev_map_alloc_node(struct net *net,
 	struct bpf_prog *prog = NULL;
 	struct bpf_dtab_netdev *dev;
 
-	dev = kmalloc_node(sizeof(*dev), GFP_ATOMIC | __GFP_NOWARN,
-			   dtab->map.numa_node);
+	dev = bpf_map_kmalloc_node(&dtab->map, sizeof(*dev),
+				   GFP_ATOMIC | __GFP_NOWARN,
+				   dtab->map.numa_node);
 	if (!dev)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.26.2

[PATCH bpf-next v9 12/34] bpf: refine memcg-based memory accounting for hashtab maps

[Roman Gushchin]

Include percpu objects and the size of map metadata into the
accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/hashtab.c | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index ec46266aaf1c..bf70fb3ed9c1 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -292,7 +292,8 @@ static int prealloc_init(struct bpf_htab *htab)
 		u32 size = round_up(htab->map.value_size, 8);
 		void __percpu *pptr;
 
-		pptr = __alloc_percpu_gfp(size, 8, GFP_USER | __GFP_NOWARN);
+		pptr = bpf_map_alloc_percpu(&htab->map, size, 8,
+					    GFP_USER | __GFP_NOWARN);
 		if (!pptr)
 			goto free_elems;
 		htab_elem_set_ptr(get_htab_elem(htab, i), htab->map.key_size,
@@ -346,8 +347,8 @@ static int alloc_extra_elems(struct bpf_htab *htab)
 	struct pcpu_freelist_node *l;
 	int cpu;
 
-	pptr = __alloc_percpu_gfp(sizeof(struct htab_elem *), 8,
-				  GFP_USER | __GFP_NOWARN);
+	pptr = bpf_map_alloc_percpu(&htab->map, sizeof(struct htab_elem *), 8,
+				    GFP_USER | __GFP_NOWARN);
 	if (!pptr)
 		return -ENOMEM;
 
@@ -444,7 +445,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 	int err, i;
 	u64 cost;
 
-	htab = kzalloc(sizeof(*htab), GFP_USER);
+	htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
 	if (!htab)
 		return ERR_PTR(-ENOMEM);
 
@@ -502,8 +503,10 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 		goto free_charge;
 
 	for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++) {
-		htab->map_locked[i] = __alloc_percpu_gfp(sizeof(int),
-							 sizeof(int), GFP_USER);
+		htab->map_locked[i] = bpf_map_alloc_percpu(&htab->map,
+							   sizeof(int),
+							   sizeof(int),
+							   GFP_USER);
 		if (!htab->map_locked[i])
 			goto free_map_locked;
 	}
@@ -925,8 +928,9 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
 				l_new = ERR_PTR(-E2BIG);
 				goto dec_count;
 			}
-		l_new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN,
-				     htab->map.numa_node);
+		l_new = bpf_map_kmalloc_node(&htab->map, htab->elem_size,
+					     GFP_ATOMIC | __GFP_NOWARN,
+					     htab->map.numa_node);
 		if (!l_new) {
 			l_new = ERR_PTR(-ENOMEM);
 			goto dec_count;
@@ -942,8 +946,8 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
 			pptr = htab_elem_get_ptr(l_new, key_size);
 		} else {
 			/* alloc_percpu zero-fills */
-			pptr = __alloc_percpu_gfp(size, 8,
-						  GFP_ATOMIC | __GFP_NOWARN);
+			pptr = bpf_map_alloc_percpu(&htab->map, size, 8,
+						    GFP_ATOMIC | __GFP_NOWARN);
 			if (!pptr) {
 				kfree(l_new);
 				l_new = ERR_PTR(-ENOMEM);
-- 
2.26.2

[PATCH bpf-next v9 13/34] bpf: memcg-based memory accounting for lpm_trie maps

[Roman Gushchin]

Include lpm trie and lpm trie node objects into the memcg-based memory
accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/lpm_trie.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index 00e32f2ec3e6..1a6981203d7f 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -282,8 +282,8 @@ static struct lpm_trie_node *lpm_trie_node_alloc(const struct lpm_trie *trie,
 	if (value)
 		size += trie->map.value_size;
 
-	node = kmalloc_node(size, GFP_ATOMIC | __GFP_NOWARN,
-			    trie->map.numa_node);
+	node = bpf_map_kmalloc_node(&trie->map, size, GFP_ATOMIC | __GFP_NOWARN,
+				    trie->map.numa_node);
 	if (!node)
 		return NULL;
 
@@ -557,7 +557,7 @@ static struct bpf_map *trie_alloc(union bpf_attr *attr)
 	    attr->value_size > LPM_VAL_SIZE_MAX)
 		return ERR_PTR(-EINVAL);
 
-	trie = kzalloc(sizeof(*trie), GFP_USER | __GFP_NOWARN);
+	trie = kzalloc(sizeof(*trie), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
 	if (!trie)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.26.2

[PATCH bpf-next v9 14/34] bpf: memcg-based memory accounting for bpf ringbuffer

[Roman Gushchin]

Enable the memcg-based memory accounting for the memory used by
the bpf ringbuffer.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/ringbuf.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c
index 31cb04a4dd2d..8983a46f6580 100644
--- a/kernel/bpf/ringbuf.c
+++ b/kernel/bpf/ringbuf.c
@@ -60,8 +60,8 @@ struct bpf_ringbuf_hdr {
 
 static struct bpf_ringbuf *bpf_ringbuf_area_alloc(size_t data_sz, int numa_node)
 {
-	const gfp_t flags = GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN |
-			    __GFP_ZERO;
+	const gfp_t flags = GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL |
+			    __GFP_NOWARN | __GFP_ZERO;
 	int nr_meta_pages = RINGBUF_PGOFF + RINGBUF_POS_PAGES;
 	int nr_data_pages = data_sz >> PAGE_SHIFT;
 	int nr_pages = nr_meta_pages + nr_data_pages;
@@ -88,10 +88,7 @@ static struct bpf_ringbuf *bpf_ringbuf_area_alloc(size_t data_sz, int numa_node)
 	 * user-space implementations significantly.
 	 */
 	array_size = (nr_meta_pages + 2 * nr_data_pages) * sizeof(*pages);
-	if (array_size > PAGE_SIZE)
-		pages = vmalloc_node(array_size, numa_node);
-	else
-		pages = kmalloc_node(array_size, flags, numa_node);
+	pages = bpf_map_area_alloc(array_size, numa_node);
 	if (!pages)
 		return NULL;
 
@@ -167,7 +164,7 @@ static struct bpf_map *ringbuf_map_alloc(union bpf_attr *attr)
 		return ERR_PTR(-E2BIG);
 #endif
 
-	rb_map = kzalloc(sizeof(*rb_map), GFP_USER);
+	rb_map = kzalloc(sizeof(*rb_map), GFP_USER | __GFP_ACCOUNT);
 	if (!rb_map)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.26.2

[PATCH bpf-next v9 15/34] bpf: memcg-based memory accounting for bpf local storage maps

[Roman Gushchin]

Account memory used by bpf local storage maps:
per-socket, per-inode and per-task storages.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 kernel/bpf/bpf_local_storage.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index 5d3a7af9ba9b..023a3eaa4d74 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -67,7 +67,8 @@ bpf_selem_alloc(struct bpf_local_storage_map *smap, void *owner,
 	if (charge_mem && mem_charge(smap, owner, smap->elem_size))
 		return NULL;
 
-	selem = kzalloc(smap->elem_size, GFP_ATOMIC | __GFP_NOWARN);
+	selem = bpf_map_kzalloc(&smap->map, smap->elem_size,
+				GFP_ATOMIC | __GFP_NOWARN);
 	if (selem) {
 		if (value)
 			memcpy(SDATA(selem)->data, value, smap->map.value_size);
@@ -264,7 +265,8 @@ int bpf_local_storage_alloc(void *owner,
 	if (err)
 		return err;
 
-	storage = kzalloc(sizeof(*storage), GFP_ATOMIC | __GFP_NOWARN);
+	storage = bpf_map_kzalloc(&smap->map, sizeof(*storage),
+				  GFP_ATOMIC | __GFP_NOWARN);
 	if (!storage) {
 		err = -ENOMEM;
 		goto uncharge;
@@ -546,7 +548,7 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
 	u64 cost;
 	int ret;
 
-	smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN);
+	smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
 	if (!smap)
 		return ERR_PTR(-ENOMEM);
 	bpf_map_init_from_attr(&smap->map, attr);
@@ -564,7 +566,7 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
 	}
 
 	smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
-				 GFP_USER | __GFP_NOWARN);
+				 GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
 	if (!smap->buckets) {
 		bpf_map_charge_finish(&smap->map.memory);
 		kfree(smap);
-- 
2.26.2

[PATCH bpf-next v9 16/34] bpf: refine memcg-based memory accounting for sockmap and sockhash maps

[Roman Gushchin]

Include internal metadata into the memcg-based memory accounting.
Also include the memory allocated on updating an element.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 net/core/sock_map.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index ddc899e83313..153652a582ee 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -39,7 +39,7 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
 	    attr->map_flags & ~SOCK_CREATE_FLAG_MASK)
 		return ERR_PTR(-EINVAL);
 
-	stab = kzalloc(sizeof(*stab), GFP_USER);
+	stab = kzalloc(sizeof(*stab), GFP_USER | __GFP_ACCOUNT);
 	if (!stab)
 		return ERR_PTR(-ENOMEM);
 
@@ -975,8 +975,9 @@ static struct bpf_shtab_elem *sock_hash_alloc_elem(struct bpf_shtab *htab,
 		}
 	}
 
-	new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN,
-			   htab->map.numa_node);
+	new = bpf_map_kmalloc_node(&htab->map, htab->elem_size,
+				   GFP_ATOMIC | __GFP_NOWARN,
+				   htab->map.numa_node);
 	if (!new) {
 		atomic_dec(&htab->count);
 		return ERR_PTR(-ENOMEM);
@@ -1116,7 +1117,7 @@ static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
 	if (attr->key_size > MAX_BPF_STACK)
 		return ERR_PTR(-E2BIG);
 
-	htab = kzalloc(sizeof(*htab), GFP_USER);
+	htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
 	if (!htab)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.26.2

[PATCH bpf-next v9 17/34] bpf: refine memcg-based memory accounting for xskmap maps

[Roman Gushchin]

Extend xskmap memory accounting to include the memory taken by
the xsk_map_node structure.

Signed-off-by: Roman Gushchin <guro@fb.com>
---
 net/xdp/xskmap.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c
index 66231ba6c348..9fff1e6dc9cd 100644
--- a/net/xdp/xskmap.c
+++ b/net/xdp/xskmap.c
@@ -16,7 +16,8 @@ static struct xsk_map_node *xsk_map_node_alloc(struct xsk_map *map,
 {
 	struct xsk_map_node *node;
 
-	node = kzalloc(sizeof(*node), GFP_ATOMIC | __GFP_NOWARN);
+	node = bpf_map_kzalloc(&map->map, sizeof(*node),
+			       GFP_ATOMIC | __GFP_NOWARN);
 	if (!node)
 		return ERR_PTR(-ENOMEM);
 
-- 
2.26.2

[PATCH bpf-next v9 18/34] bpf: eliminate rlimit-based memory accounting for arraymap maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for arraymap maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/arraymap.c | 24 ++++--------------------
 1 file changed, 4 insertions(+), 20 deletions(-)

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index d837e0603c89..1f8453343bf2 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -81,11 +81,10 @@ int array_map_alloc_check(union bpf_attr *attr)
 static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 {
 	bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
-	int ret, numa_node = bpf_map_attr_numa_node(attr);
+	int numa_node = bpf_map_attr_numa_node(attr);
 	u32 elem_size, index_mask, max_entries;
 	bool bypass_spec_v1 = bpf_bypass_spec_v1();
-	u64 cost, array_size, mask64;
-	struct bpf_map_memory mem;
+	u64 array_size, mask64;
 	struct bpf_array *array;
 
 	elem_size = round_up(attr->value_size, 8);
@@ -126,44 +125,29 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 		}
 	}
 
-	/* make sure there is no u32 overflow later in round_up() */
-	cost = array_size;
-	if (percpu)
-		cost += (u64)attr->max_entries * elem_size * num_possible_cpus();
-
-	ret = bpf_map_charge_init(&mem, cost);
-	if (ret < 0)
-		return ERR_PTR(ret);
-
 	/* allocate all map elements and zero-initialize them */
 	if (attr->map_flags & BPF_F_MMAPABLE) {
 		void *data;
 
 		/* kmalloc'ed memory can't be mmap'ed, use explicit vmalloc */
 		data = bpf_map_area_mmapable_alloc(array_size, numa_node);
-		if (!data) {
-			bpf_map_charge_finish(&mem);
+		if (!data)
 			return ERR_PTR(-ENOMEM);
-		}
 		array = data + PAGE_ALIGN(sizeof(struct bpf_array))
 			- offsetof(struct bpf_array, value);
 	} else {
 		array = bpf_map_area_alloc(array_size, numa_node);
 	}
-	if (!array) {
-		bpf_map_charge_finish(&mem);
+	if (!array)
 		return ERR_PTR(-ENOMEM);
-	}
 	array->index_mask = index_mask;
 	array->map.bypass_spec_v1 = bypass_spec_v1;
 
 	/* copy mandatory map attributes */
 	bpf_map_init_from_attr(&array->map, attr);
-	bpf_map_charge_move(&array->map.memory, &mem);
 	array->elem_size = elem_size;
 
 	if (percpu && bpf_array_alloc_percpu(array)) {
-		bpf_map_charge_finish(&array->map.memory);
 		bpf_map_area_free(array);
 		return ERR_PTR(-ENOMEM);
 	}
-- 
2.26.2

[PATCH bpf-next v9 19/34] bpf: eliminate rlimit-based memory accounting for bpf_struct_ops maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for bpf_struct_ops maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/bpf_struct_ops.c | 19 +++----------------
 1 file changed, 3 insertions(+), 16 deletions(-)

diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 4c3b543bb33b..1a666a975416 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -548,12 +548,10 @@ static int bpf_struct_ops_map_alloc_check(union bpf_attr *attr)
 static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
 {
 	const struct bpf_struct_ops *st_ops;
-	size_t map_total_size, st_map_size;
+	size_t st_map_size;
 	struct bpf_struct_ops_map *st_map;
 	const struct btf_type *t, *vt;
-	struct bpf_map_memory mem;
 	struct bpf_map *map;
-	int err;
 
 	if (!bpf_capable())
 		return ERR_PTR(-EPERM);
@@ -573,20 +571,11 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
 		 * struct bpf_struct_ops_tcp_congestions_ops
 		 */
 		(vt->size - sizeof(struct bpf_struct_ops_value));
-	map_total_size = st_map_size +
-		/* uvalue */
-		sizeof(vt->size) +
-		/* struct bpf_progs **progs */
-		 btf_type_vlen(t) * sizeof(struct bpf_prog *);
-	err = bpf_map_charge_init(&mem, map_total_size);
-	if (err < 0)
-		return ERR_PTR(err);
 
 	st_map = bpf_map_area_alloc(st_map_size, NUMA_NO_NODE);
-	if (!st_map) {
-		bpf_map_charge_finish(&mem);
+	if (!st_map)
 		return ERR_PTR(-ENOMEM);
-	}
+
 	st_map->st_ops = st_ops;
 	map = &st_map->map;
 
@@ -597,14 +586,12 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr)
 	st_map->image = bpf_jit_alloc_exec(PAGE_SIZE);
 	if (!st_map->uvalue || !st_map->progs || !st_map->image) {
 		bpf_struct_ops_map_free(map);
-		bpf_map_charge_finish(&mem);
 		return ERR_PTR(-ENOMEM);
 	}
 
 	mutex_init(&st_map->lock);
 	set_vm_flush_reset_perms(st_map->image);
 	bpf_map_init_from_attr(map, attr);
-	bpf_map_charge_move(&map->memory, &mem);
 
 	return map;
 }
-- 
2.26.2

[PATCH bpf-next v9 20/34] bpf: eliminate rlimit-based memory accounting for cpumap maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for cpumap maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/cpumap.c | 16 +---------------
 1 file changed, 1 insertion(+), 15 deletions(-)

diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index 90b949666605..747313698178 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -84,8 +84,6 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
 	u32 value_size = attr->value_size;
 	struct bpf_cpu_map *cmap;
 	int err = -ENOMEM;
-	u64 cost;
-	int ret;
 
 	if (!bpf_capable())
 		return ERR_PTR(-EPERM);
@@ -109,26 +107,14 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)
 		goto free_cmap;
 	}
 
-	/* make sure page count doesn't overflow */
-	cost = (u64) cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *);
-
-	/* Notice returns -EPERM on if map size is larger than memlock limit */
-	ret = bpf_map_charge_init(&cmap->map.memory, cost);
-	if (ret) {
-		err = ret;
-		goto free_cmap;
-	}
-
 	/* Alloc array for possible remote "destination" CPUs */
 	cmap->cpu_map = bpf_map_area_alloc(cmap->map.max_entries *
 					   sizeof(struct bpf_cpu_map_entry *),
 					   cmap->map.numa_node);
 	if (!cmap->cpu_map)
-		goto free_charge;
+		goto free_cmap;
 
 	return &cmap->map;
-free_charge:
-	bpf_map_charge_finish(&cmap->map.memory);
 free_cmap:
 	kfree(cmap);
 	return ERR_PTR(err);
-- 
2.26.2

[PATCH bpf-next v9 21/34] bpf: eliminate rlimit-based memory accounting for cgroup storage maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for cgroup storage maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/local_storage.c | 21 +--------------------
 1 file changed, 1 insertion(+), 20 deletions(-)

diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 74dcee8926e5..2d4f9ac12377 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -287,8 +287,6 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
 {
 	int numa_node = bpf_map_attr_numa_node(attr);
 	struct bpf_cgroup_storage_map *map;
-	struct bpf_map_memory mem;
-	int ret;
 
 	if (attr->key_size != sizeof(struct bpf_cgroup_storage_key) &&
 	    attr->key_size != sizeof(__u64))
@@ -308,18 +306,10 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr)
 		/* max_entries is not used and enforced to be 0 */
 		return ERR_PTR(-EINVAL);
 
-	ret = bpf_map_charge_init(&mem, sizeof(struct bpf_cgroup_storage_map));
-	if (ret < 0)
-		return ERR_PTR(ret);
-
 	map = kmalloc_node(sizeof(struct bpf_cgroup_storage_map),
 			   __GFP_ZERO | GFP_USER | __GFP_ACCOUNT, numa_node);
-	if (!map) {
-		bpf_map_charge_finish(&mem);
+	if (!map)
 		return ERR_PTR(-ENOMEM);
-	}
-
-	bpf_map_charge_move(&map->map.memory, &mem);
 
 	/* copy mandatory map attributes */
 	bpf_map_init_from_attr(&map->map, attr);
@@ -508,9 +498,6 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 
 	size = bpf_cgroup_storage_calculate_size(map, &pages);
 
-	if (bpf_map_charge_memlock(map, pages))
-		return ERR_PTR(-EPERM);
-
 	storage = bpf_map_kmalloc_node(map, sizeof(struct bpf_cgroup_storage),
 				       gfp, map->numa_node);
 	if (!storage)
@@ -533,7 +520,6 @@ struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
 	return storage;
 
 enomem:
-	bpf_map_uncharge_memlock(map, pages);
 	kfree(storage);
 	return ERR_PTR(-ENOMEM);
 }
@@ -560,16 +546,11 @@ void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage)
 {
 	enum bpf_cgroup_storage_type stype;
 	struct bpf_map *map;
-	u32 pages;
 
 	if (!storage)
 		return;
 
 	map = &storage->map->map;
-
-	bpf_cgroup_storage_calculate_size(map, &pages);
-	bpf_map_uncharge_memlock(map, pages);
-
 	stype = cgroup_storage_type(map);
 	if (stype == BPF_CGROUP_STORAGE_SHARED)
 		call_rcu(&storage->rcu, free_shared_cgroup_storage_rcu);
-- 
2.26.2

[PATCH bpf-next v9 22/34] bpf: eliminate rlimit-based memory accounting for devmap maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for devmap maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/devmap.c | 18 ++----------------
 1 file changed, 2 insertions(+), 16 deletions(-)

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index b43ab247302d..f6e9c68afdd4 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -109,8 +109,6 @@ static inline struct hlist_head *dev_map_index_hash(struct bpf_dtab *dtab,
 static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
 {
 	u32 valsize = attr->value_size;
-	u64 cost = 0;
-	int err;
 
 	/* check sanity of attributes. 2 value sizes supported:
 	 * 4 bytes: ifindex
@@ -135,21 +133,13 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
 
 		if (!dtab->n_buckets) /* Overflow check */
 			return -EINVAL;
-		cost += (u64) sizeof(struct hlist_head) * dtab->n_buckets;
-	} else {
-		cost += (u64) dtab->map.max_entries * sizeof(struct bpf_dtab_netdev *);
 	}
 
-	/* if map size is larger than memlock limit, reject it */
-	err = bpf_map_charge_init(&dtab->map.memory, cost);
-	if (err)
-		return -EINVAL;
-
 	if (attr->map_type == BPF_MAP_TYPE_DEVMAP_HASH) {
 		dtab->dev_index_head = dev_map_create_hash(dtab->n_buckets,
 							   dtab->map.numa_node);
 		if (!dtab->dev_index_head)
-			goto free_charge;
+			return -ENOMEM;
 
 		spin_lock_init(&dtab->index_lock);
 	} else {
@@ -157,14 +147,10 @@ static int dev_map_init_map(struct bpf_dtab *dtab, union bpf_attr *attr)
 						      sizeof(struct bpf_dtab_netdev *),
 						      dtab->map.numa_node);
 		if (!dtab->netdev_map)
-			goto free_charge;
+			return -ENOMEM;
 	}
 
 	return 0;
-
-free_charge:
-	bpf_map_charge_finish(&dtab->map.memory);
-	return -ENOMEM;
 }
 
 static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
-- 
2.26.2

[PATCH bpf-next v9 23/34] bpf: eliminate rlimit-based memory accounting for hashtab maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for hashtab maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/hashtab.c | 19 +------------------
 1 file changed, 1 insertion(+), 18 deletions(-)

diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index bf70fb3ed9c1..fe7a0733a63a 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -443,7 +443,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 	bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
 	struct bpf_htab *htab;
 	int err, i;
-	u64 cost;
 
 	htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
 	if (!htab)
@@ -481,26 +480,12 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 	    htab->n_buckets > U32_MAX / sizeof(struct bucket))
 		goto free_htab;
 
-	cost = (u64) htab->n_buckets * sizeof(struct bucket) +
-	       (u64) htab->elem_size * htab->map.max_entries;
-
-	if (percpu)
-		cost += (u64) round_up(htab->map.value_size, 8) *
-			num_possible_cpus() * htab->map.max_entries;
-	else
-	       cost += (u64) htab->elem_size * num_possible_cpus();
-
-	/* if map size is larger than memlock limit, reject it */
-	err = bpf_map_charge_init(&htab->map.memory, cost);
-	if (err)
-		goto free_htab;
-
 	err = -ENOMEM;
 	htab->buckets = bpf_map_area_alloc(htab->n_buckets *
 					   sizeof(struct bucket),
 					   htab->map.numa_node);
 	if (!htab->buckets)
-		goto free_charge;
+		goto free_htab;
 
 	for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++) {
 		htab->map_locked[i] = bpf_map_alloc_percpu(&htab->map,
@@ -541,8 +526,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
 	for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++)
 		free_percpu(htab->map_locked[i]);
 	bpf_map_area_free(htab->buckets);
-free_charge:
-	bpf_map_charge_finish(&htab->map.memory);
 free_htab:
 	lockdep_unregister_key(&htab->lockdep_key);
 	kfree(htab);
-- 
2.26.2

[PATCH bpf-next v9 24/34] bpf: eliminate rlimit-based memory accounting for lpm_trie maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for lpm_trie maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/lpm_trie.c | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/kernel/bpf/lpm_trie.c b/kernel/bpf/lpm_trie.c
index 1a6981203d7f..cec792a17e5f 100644
--- a/kernel/bpf/lpm_trie.c
+++ b/kernel/bpf/lpm_trie.c
@@ -540,8 +540,6 @@ static int trie_delete_elem(struct bpf_map *map, void *_key)
 static struct bpf_map *trie_alloc(union bpf_attr *attr)
 {
 	struct lpm_trie *trie;
-	u64 cost = sizeof(*trie), cost_per_node;
-	int ret;
 
 	if (!bpf_capable())
 		return ERR_PTR(-EPERM);
@@ -567,20 +565,9 @@ static struct bpf_map *trie_alloc(union bpf_attr *attr)
 			  offsetof(struct bpf_lpm_trie_key, data);
 	trie->max_prefixlen = trie->data_size * 8;
 
-	cost_per_node = sizeof(struct lpm_trie_node) +
-			attr->value_size + trie->data_size;
-	cost += (u64) attr->max_entries * cost_per_node;
-
-	ret = bpf_map_charge_init(&trie->map.memory, cost);
-	if (ret)
-		goto out_err;
-
 	spin_lock_init(&trie->lock);
 
 	return &trie->map;
-out_err:
-	kfree(trie);
-	return ERR_PTR(ret);
 }
 
 static void trie_free(struct bpf_map *map)
-- 
2.26.2

[PATCH bpf-next v9 25/34] bpf: eliminate rlimit-based memory accounting for queue_stack_maps maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for queue_stack maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/queue_stack_maps.c | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/kernel/bpf/queue_stack_maps.c b/kernel/bpf/queue_stack_maps.c
index 0ee2347ba510..f9c734aaa990 100644
--- a/kernel/bpf/queue_stack_maps.c
+++ b/kernel/bpf/queue_stack_maps.c
@@ -66,29 +66,21 @@ static int queue_stack_map_alloc_check(union bpf_attr *attr)
 
 static struct bpf_map *queue_stack_map_alloc(union bpf_attr *attr)
 {
-	int ret, numa_node = bpf_map_attr_numa_node(attr);
-	struct bpf_map_memory mem = {0};
+	int numa_node = bpf_map_attr_numa_node(attr);
 	struct bpf_queue_stack *qs;
-	u64 size, queue_size, cost;
+	u64 size, queue_size;
 
 	size = (u64) attr->max_entries + 1;
-	cost = queue_size = sizeof(*qs) + size * attr->value_size;
-
-	ret = bpf_map_charge_init(&mem, cost);
-	if (ret < 0)
-		return ERR_PTR(ret);
+	queue_size = sizeof(*qs) + size * attr->value_size;
 
 	qs = bpf_map_area_alloc(queue_size, numa_node);
-	if (!qs) {
-		bpf_map_charge_finish(&mem);
+	if (!qs)
 		return ERR_PTR(-ENOMEM);
-	}
 
 	memset(qs, 0, sizeof(*qs));
 
 	bpf_map_init_from_attr(&qs->map, attr);
 
-	bpf_map_charge_move(&qs->map.memory, &mem);
 	qs->size = size;
 
 	raw_spin_lock_init(&qs->lock);
-- 
2.26.2

[PATCH bpf-next v9 26/34] bpf: eliminate rlimit-based memory accounting for reuseport_array maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for reuseport_array maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/reuseport_array.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/kernel/bpf/reuseport_array.c b/kernel/bpf/reuseport_array.c
index a55cd542f2ce..4838922f723d 100644
--- a/kernel/bpf/reuseport_array.c
+++ b/kernel/bpf/reuseport_array.c
@@ -150,9 +150,8 @@ static void reuseport_array_free(struct bpf_map *map)
 
 static struct bpf_map *reuseport_array_alloc(union bpf_attr *attr)
 {
-	int err, numa_node = bpf_map_attr_numa_node(attr);
+	int numa_node = bpf_map_attr_numa_node(attr);
 	struct reuseport_array *array;
-	struct bpf_map_memory mem;
 	u64 array_size;
 
 	if (!bpf_capable())
@@ -161,20 +160,13 @@ static struct bpf_map *reuseport_array_alloc(union bpf_attr *attr)
 	array_size = sizeof(*array);
 	array_size += (u64)attr->max_entries * sizeof(struct sock *);
 
-	err = bpf_map_charge_init(&mem, array_size);
-	if (err)
-		return ERR_PTR(err);
-
 	/* allocate all map elements and zero-initialize them */
 	array = bpf_map_area_alloc(array_size, numa_node);
-	if (!array) {
-		bpf_map_charge_finish(&mem);
+	if (!array)
 		return ERR_PTR(-ENOMEM);
-	}
 
 	/* copy mandatory map attributes */
 	bpf_map_init_from_attr(&array->map, attr);
-	bpf_map_charge_move(&array->map.memory, &mem);
 
 	return &array->map;
 }
-- 
2.26.2

[PATCH bpf-next v9 27/34] bpf: eliminate rlimit-based memory accounting for bpf ringbuffer

[Roman Gushchin]

Do not use rlimit-based memory accounting for bpf ringbuffer.
It has been replaced with the memcg-based memory accounting.

bpf_ringbuf_alloc() can't return anything except ERR_PTR(-ENOMEM)
and a valid pointer, so to simplify the code make it return NULL
in the first case. This allows to drop a couple of lines in
ringbuf_map_alloc() and also makes it look similar to other memory
allocating function like kmalloc().

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
---
 kernel/bpf/ringbuf.c | 24 ++++--------------------
 1 file changed, 4 insertions(+), 20 deletions(-)

diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c
index 8983a46f6580..f25b719ac786 100644
--- a/kernel/bpf/ringbuf.c
+++ b/kernel/bpf/ringbuf.c
@@ -48,7 +48,6 @@ struct bpf_ringbuf {
 
 struct bpf_ringbuf_map {
 	struct bpf_map map;
-	struct bpf_map_memory memory;
 	struct bpf_ringbuf *rb;
 };
 
@@ -131,7 +130,7 @@ static struct bpf_ringbuf *bpf_ringbuf_alloc(size_t data_sz, int numa_node)
 
 	rb = bpf_ringbuf_area_alloc(data_sz, numa_node);
 	if (!rb)
-		return ERR_PTR(-ENOMEM);
+		return NULL;
 
 	spin_lock_init(&rb->spinlock);
 	init_waitqueue_head(&rb->waitq);
@@ -147,8 +146,6 @@ static struct bpf_ringbuf *bpf_ringbuf_alloc(size_t data_sz, int numa_node)
 static struct bpf_map *ringbuf_map_alloc(union bpf_attr *attr)
 {
 	struct bpf_ringbuf_map *rb_map;
-	u64 cost;
-	int err;
 
 	if (attr->map_flags & ~RINGBUF_CREATE_FLAG_MASK)
 		return ERR_PTR(-EINVAL);
@@ -170,26 +167,13 @@ static struct bpf_map *ringbuf_map_alloc(union bpf_attr *attr)
 
 	bpf_map_init_from_attr(&rb_map->map, attr);
 
-	cost = sizeof(struct bpf_ringbuf_map) +
-	       sizeof(struct bpf_ringbuf) +
-	       attr->max_entries;
-	err = bpf_map_charge_init(&rb_map->map.memory, cost);
-	if (err)
-		goto err_free_map;
-
 	rb_map->rb = bpf_ringbuf_alloc(attr->max_entries, rb_map->map.numa_node);
-	if (IS_ERR(rb_map->rb)) {
-		err = PTR_ERR(rb_map->rb);
-		goto err_uncharge;
+	if (!rb_map->rb) {
+		kfree(rb_map);
+		return ERR_PTR(-ENOMEM);
 	}
 
 	return &rb_map->map;
-
-err_uncharge:
-	bpf_map_charge_finish(&rb_map->map.memory);
-err_free_map:
-	kfree(rb_map);
-	return ERR_PTR(err);
 }
 
 static void bpf_ringbuf_free(struct bpf_ringbuf *rb)
-- 
2.26.2

[PATCH bpf-next v9 28/34] bpf: eliminate rlimit-based memory accounting for sockmap and sockhash maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for sockmap and sockhash maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 net/core/sock_map.c | 33 ++++++---------------------------
 1 file changed, 6 insertions(+), 27 deletions(-)

diff --git a/net/core/sock_map.c b/net/core/sock_map.c
index 153652a582ee..64b5ec14ff50 100644
--- a/net/core/sock_map.c
+++ b/net/core/sock_map.c
@@ -27,8 +27,6 @@ struct bpf_stab {
 static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
 {
 	struct bpf_stab *stab;
-	u64 cost;
-	int err;
 
 	if (!capable(CAP_NET_ADMIN))
 		return ERR_PTR(-EPERM);
@@ -46,22 +44,15 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
 	bpf_map_init_from_attr(&stab->map, attr);
 	raw_spin_lock_init(&stab->lock);
 
-	/* Make sure page count doesn't overflow. */
-	cost = (u64) stab->map.max_entries * sizeof(struct sock *);
-	err = bpf_map_charge_init(&stab->map.memory, cost);
-	if (err)
-		goto free_stab;
-
 	stab->sks = bpf_map_area_alloc(stab->map.max_entries *
 				       sizeof(struct sock *),
 				       stab->map.numa_node);
-	if (stab->sks)
-		return &stab->map;
-	err = -ENOMEM;
-	bpf_map_charge_finish(&stab->map.memory);
-free_stab:
-	kfree(stab);
-	return ERR_PTR(err);
+	if (!stab->sks) {
+		kfree(stab);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	return &stab->map;
 }
 
 int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog)
@@ -1104,7 +1095,6 @@ static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
 {
 	struct bpf_shtab *htab;
 	int i, err;
-	u64 cost;
 
 	if (!capable(CAP_NET_ADMIN))
 		return ERR_PTR(-EPERM);
@@ -1132,21 +1122,10 @@ static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
 		goto free_htab;
 	}
 
-	cost = (u64) htab->buckets_num * sizeof(struct bpf_shtab_bucket) +
-	       (u64) htab->elem_size * htab->map.max_entries;
-	if (cost >= U32_MAX - PAGE_SIZE) {
-		err = -EINVAL;
-		goto free_htab;
-	}
-	err = bpf_map_charge_init(&htab->map.memory, cost);
-	if (err)
-		goto free_htab;
-
 	htab->buckets = bpf_map_area_alloc(htab->buckets_num *
 					   sizeof(struct bpf_shtab_bucket),
 					   htab->map.numa_node);
 	if (!htab->buckets) {
-		bpf_map_charge_finish(&htab->map.memory);
 		err = -ENOMEM;
 		goto free_htab;
 	}
-- 
2.26.2

[PATCH bpf-next v9 29/34] bpf: eliminate rlimit-based memory accounting for stackmap maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for stackmap maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/stackmap.c | 16 +++-------------
 1 file changed, 3 insertions(+), 13 deletions(-)

diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 06065fa27124..3325add8e629 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -90,7 +90,6 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
 {
 	u32 value_size = attr->value_size;
 	struct bpf_stack_map *smap;
-	struct bpf_map_memory mem;
 	u64 cost, n_buckets;
 	int err;
 
@@ -119,15 +118,9 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
 
 	cost = n_buckets * sizeof(struct stack_map_bucket *) + sizeof(*smap);
 	cost += n_buckets * (value_size + sizeof(struct stack_map_bucket));
-	err = bpf_map_charge_init(&mem, cost);
-	if (err)
-		return ERR_PTR(err);
-
 	smap = bpf_map_area_alloc(cost, bpf_map_attr_numa_node(attr));
-	if (!smap) {
-		bpf_map_charge_finish(&mem);
+	if (!smap)
 		return ERR_PTR(-ENOMEM);
-	}
 
 	bpf_map_init_from_attr(&smap->map, attr);
 	smap->map.value_size = value_size;
@@ -135,20 +128,17 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
 
 	err = get_callchain_buffers(sysctl_perf_event_max_stack);
 	if (err)
-		goto free_charge;
+		goto free_smap;
 
 	err = prealloc_elems_and_freelist(smap);
 	if (err)
 		goto put_buffers;
 
-	bpf_map_charge_move(&smap->map.memory, &mem);
-
 	return &smap->map;
 
 put_buffers:
 	put_callchain_buffers();
-free_charge:
-	bpf_map_charge_finish(&mem);
+free_smap:
 	bpf_map_area_free(smap);
 	return ERR_PTR(err);
 }
-- 
2.26.2

[PATCH bpf-next v9 30/34] bpf: eliminate rlimit-based memory accounting for xskmap maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for xskmap maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 net/xdp/xskmap.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/net/xdp/xskmap.c b/net/xdp/xskmap.c
index 9fff1e6dc9cd..113fd9017203 100644
--- a/net/xdp/xskmap.c
+++ b/net/xdp/xskmap.c
@@ -58,9 +58,8 @@ static void xsk_map_sock_delete(struct xdp_sock *xs,
 
 static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
 {
-	struct bpf_map_memory mem;
-	int err, numa_node;
 	struct xsk_map *m;
+	int numa_node;
 	u64 size;
 
 	if (!capable(CAP_NET_ADMIN))
@@ -74,18 +73,11 @@ static struct bpf_map *xsk_map_alloc(union bpf_attr *attr)
 	numa_node = bpf_map_attr_numa_node(attr);
 	size = struct_size(m, xsk_map, attr->max_entries);
 
-	err = bpf_map_charge_init(&mem, size);
-	if (err < 0)
-		return ERR_PTR(err);
-
 	m = bpf_map_area_alloc(size, numa_node);
-	if (!m) {
-		bpf_map_charge_finish(&mem);
+	if (!m)
 		return ERR_PTR(-ENOMEM);
-	}
 
 	bpf_map_init_from_attr(&m->map, attr);
-	bpf_map_charge_move(&m->map.memory, &mem);
 	spin_lock_init(&m->lock);
 
 	return &m->map;
-- 
2.26.2

[PATCH bpf-next v9 31/34] bpf: eliminate rlimit-based memory accounting for bpf local storage maps

[Roman Gushchin]

Do not use rlimit-based memory accounting for bpf local storage maps.
It has been replaced with the memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 kernel/bpf/bpf_local_storage.c | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c
index 023a3eaa4d74..dd5aedee99e7 100644
--- a/kernel/bpf/bpf_local_storage.c
+++ b/kernel/bpf/bpf_local_storage.c
@@ -545,8 +545,6 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
 	struct bpf_local_storage_map *smap;
 	unsigned int i;
 	u32 nbuckets;
-	u64 cost;
-	int ret;
 
 	smap = kzalloc(sizeof(*smap), GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
 	if (!smap)
@@ -557,18 +555,10 @@ struct bpf_local_storage_map *bpf_local_storage_map_alloc(union bpf_attr *attr)
 	/* Use at least 2 buckets, select_bucket() is undefined behavior with 1 bucket */
 	nbuckets = max_t(u32, 2, nbuckets);
 	smap->bucket_log = ilog2(nbuckets);
-	cost = sizeof(*smap->buckets) * nbuckets + sizeof(*smap);
-
-	ret = bpf_map_charge_init(&smap->map.memory, cost);
-	if (ret < 0) {
-		kfree(smap);
-		return ERR_PTR(ret);
-	}
 
 	smap->buckets = kvcalloc(sizeof(*smap->buckets), nbuckets,
 				 GFP_USER | __GFP_NOWARN | __GFP_ACCOUNT);
 	if (!smap->buckets) {
-		bpf_map_charge_finish(&smap->map.memory);
 		kfree(smap);
 		return ERR_PTR(-ENOMEM);
 	}
-- 
2.26.2

[PATCH bpf-next v9 32/34] bpf: eliminate rlimit-based memory accounting infra for bpf maps

[Roman Gushchin]

Remove rlimit-based accounting infrastructure code, which is not used
anymore.

To provide a backward compatibility, use an approximation of the
bpf map memory footprint as a "memlock" value, available to a user
via map info. The approximation is based on the maximal number of
elements and key and value sizes.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 include/linux/bpf.h                           | 12 ---
 kernel/bpf/syscall.c                          | 96 ++++---------------
 .../selftests/bpf/progs/bpf_iter_bpf_map.c    |  2 +-
 .../selftests/bpf/progs/map_ptr_kern.c        |  7 --
 4 files changed, 17 insertions(+), 100 deletions(-)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index e1f2c95c15ec..61331a148cde 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -138,11 +138,6 @@ struct bpf_map_ops {
 	const struct bpf_iter_seq_info *iter_seq_info;
 };
 
-struct bpf_map_memory {
-	u32 pages;
-	struct user_struct *user;
-};
-
 struct bpf_map {
 	/* The first two cachelines with read-mostly members of which some
 	 * are also accessed in fast-path (e.g. ops, max_entries).
@@ -163,7 +158,6 @@ struct bpf_map {
 	u32 btf_key_type_id;
 	u32 btf_value_type_id;
 	struct btf *btf;
-	struct bpf_map_memory memory;
 #ifdef CONFIG_MEMCG_KMEM
 	struct mem_cgroup *memcg;
 #endif
@@ -1224,12 +1218,6 @@ void bpf_map_inc_with_uref(struct bpf_map *map);
 struct bpf_map * __must_check bpf_map_inc_not_zero(struct bpf_map *map);
 void bpf_map_put_with_uref(struct bpf_map *map);
 void bpf_map_put(struct bpf_map *map);
-int bpf_map_charge_memlock(struct bpf_map *map, u32 pages);
-void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages);
-int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size);
-void bpf_map_charge_finish(struct bpf_map_memory *mem);
-void bpf_map_charge_move(struct bpf_map_memory *dst,
-			 struct bpf_map_memory *src);
 void *bpf_map_area_alloc(u64 size, int numa_node);
 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node);
 void bpf_map_area_free(void *base);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index dff3a5f62d7a..29096d96d989 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -128,7 +128,7 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
 	return map;
 }
 
-static u32 bpf_map_value_size(struct bpf_map *map)
+static u32 bpf_map_value_size(const struct bpf_map *map)
 {
 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
@@ -346,77 +346,6 @@ void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
 	map->numa_node = bpf_map_attr_numa_node(attr);
 }
 
-static int bpf_charge_memlock(struct user_struct *user, u32 pages)
-{
-	unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
-
-	if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
-		atomic_long_sub(pages, &user->locked_vm);
-		return -EPERM;
-	}
-	return 0;
-}
-
-static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
-{
-	if (user)
-		atomic_long_sub(pages, &user->locked_vm);
-}
-
-int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
-{
-	u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
-	struct user_struct *user;
-	int ret;
-
-	if (size >= U32_MAX - PAGE_SIZE)
-		return -E2BIG;
-
-	user = get_current_user();
-	ret = bpf_charge_memlock(user, pages);
-	if (ret) {
-		free_uid(user);
-		return ret;
-	}
-
-	mem->pages = pages;
-	mem->user = user;
-
-	return 0;
-}
-
-void bpf_map_charge_finish(struct bpf_map_memory *mem)
-{
-	bpf_uncharge_memlock(mem->user, mem->pages);
-	free_uid(mem->user);
-}
-
-void bpf_map_charge_move(struct bpf_map_memory *dst,
-			 struct bpf_map_memory *src)
-{
-	*dst = *src;
-
-	/* Make sure src will not be used for the redundant uncharging. */
-	memset(src, 0, sizeof(struct bpf_map_memory));
-}
-
-int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
-{
-	int ret;
-
-	ret = bpf_charge_memlock(map->memory.user, pages);
-	if (ret)
-		return ret;
-	map->memory.pages += pages;
-	return ret;
-}
-
-void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
-{
-	bpf_uncharge_memlock(map->memory.user, pages);
-	map->memory.pages -= pages;
-}
-
 static int bpf_map_alloc_id(struct bpf_map *map)
 {
 	int id;
@@ -524,14 +453,11 @@ static void bpf_map_release_memcg(struct bpf_map *map)
 static void bpf_map_free_deferred(struct work_struct *work)
 {
 	struct bpf_map *map = container_of(work, struct bpf_map, work);
-	struct bpf_map_memory mem;
 
-	bpf_map_charge_move(&mem, &map->memory);
 	security_bpf_map_free(map);
 	bpf_map_release_memcg(map);
 	/* implementation dependent freeing */
 	map->ops->map_free(map);
-	bpf_map_charge_finish(&mem);
 }
 
 static void bpf_map_put_uref(struct bpf_map *map)
@@ -592,6 +518,19 @@ static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
 }
 
 #ifdef CONFIG_PROC_FS
+/* Provides an approximation of the map's memory footprint.
+ * Used only to provide a backward compatibility and display
+ * a reasonable "memlock" info.
+ */
+static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
+{
+	unsigned long size;
+
+	size = round_up(map->key_size + bpf_map_value_size(map), 8);
+
+	return round_up(map->max_entries * size, PAGE_SIZE);
+}
+
 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 {
 	const struct bpf_map *map = filp->private_data;
@@ -610,7 +549,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 		   "value_size:\t%u\n"
 		   "max_entries:\t%u\n"
 		   "map_flags:\t%#x\n"
-		   "memlock:\t%llu\n"
+		   "memlock:\t%lu\n"
 		   "map_id:\t%u\n"
 		   "frozen:\t%u\n",
 		   map->map_type,
@@ -618,7 +557,7 @@ static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
 		   map->value_size,
 		   map->max_entries,
 		   map->map_flags,
-		   map->memory.pages * 1ULL << PAGE_SHIFT,
+		   bpf_map_memory_footprint(map),
 		   map->id,
 		   READ_ONCE(map->frozen));
 	if (type) {
@@ -861,7 +800,6 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
 static int map_create(union bpf_attr *attr)
 {
 	int numa_node = bpf_map_attr_numa_node(attr);
-	struct bpf_map_memory mem;
 	struct bpf_map *map;
 	int f_flags;
 	int err;
@@ -960,9 +898,7 @@ static int map_create(union bpf_attr *attr)
 	security_bpf_map_free(map);
 free_map:
 	btf_put(map->btf);
-	bpf_map_charge_move(&mem, &map->memory);
 	map->ops->map_free(map);
-	bpf_map_charge_finish(&mem);
 	return err;
 }
 
diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c
index 08651b23edba..b83b5d2e17dc 100644
--- a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_map.c
@@ -23,6 +23,6 @@ int dump_bpf_map(struct bpf_iter__bpf_map *ctx)
 
 	BPF_SEQ_PRINTF(seq, "%8u %8ld %8ld %10lu\n", map->id, map->refcnt.counter,
 		       map->usercnt.counter,
-		       map->memory.user->locked_vm.counter);
+		       0LLU);
 	return 0;
 }
diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
index c325405751e2..d8850bc6a9f1 100644
--- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
+++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
@@ -26,17 +26,12 @@ __u32 g_line = 0;
 		return 0;	\
 })
 
-struct bpf_map_memory {
-	__u32 pages;
-} __attribute__((preserve_access_index));
-
 struct bpf_map {
 	enum bpf_map_type map_type;
 	__u32 key_size;
 	__u32 value_size;
 	__u32 max_entries;
 	__u32 id;
-	struct bpf_map_memory memory;
 } __attribute__((preserve_access_index));
 
 static inline int check_bpf_map_fields(struct bpf_map *map, __u32 key_size,
@@ -47,7 +42,6 @@ static inline int check_bpf_map_fields(struct bpf_map *map, __u32 key_size,
 	VERIFY(map->value_size == value_size);
 	VERIFY(map->max_entries == max_entries);
 	VERIFY(map->id > 0);
-	VERIFY(map->memory.pages > 0);
 
 	return 1;
 }
@@ -60,7 +54,6 @@ static inline int check_bpf_map_ptr(struct bpf_map *indirect,
 	VERIFY(indirect->value_size == direct->value_size);
 	VERIFY(indirect->max_entries == direct->max_entries);
 	VERIFY(indirect->id == direct->id);
-	VERIFY(indirect->memory.pages == direct->memory.pages);
 
 	return 1;
 }
-- 
2.26.2

[PATCH bpf-next v9 33/34] bpf: eliminate rlimit-based memory accounting for bpf progs

[Roman Gushchin]

Do not use rlimit-based memory accounting for bpf progs. It has been
replaced with memcg-based memory accounting.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 include/linux/bpf.h  | 11 -------
 kernel/bpf/core.c    | 12 ++------
 kernel/bpf/syscall.c | 69 +++++++-------------------------------------
 3 files changed, 12 insertions(+), 80 deletions(-)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 61331a148cde..a9de5711b23f 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1202,8 +1202,6 @@ void bpf_prog_sub(struct bpf_prog *prog, int i);
 void bpf_prog_inc(struct bpf_prog *prog);
 struct bpf_prog * __must_check bpf_prog_inc_not_zero(struct bpf_prog *prog);
 void bpf_prog_put(struct bpf_prog *prog);
-int __bpf_prog_charge(struct user_struct *user, u32 pages);
-void __bpf_prog_uncharge(struct user_struct *user, u32 pages);
 void __bpf_free_used_maps(struct bpf_prog_aux *aux,
 			  struct bpf_map **used_maps, u32 len);
 
@@ -1512,15 +1510,6 @@ bpf_prog_inc_not_zero(struct bpf_prog *prog)
 	return ERR_PTR(-EOPNOTSUPP);
 }
 
-static inline int __bpf_prog_charge(struct user_struct *user, u32 pages)
-{
-	return 0;
-}
-
-static inline void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
-{
-}
-
 static inline void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
 				 const struct bpf_link_ops *ops,
 				 struct bpf_prog *prog)
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 2921f58c03a8..261f8692d0d2 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -221,23 +221,15 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 {
 	gfp_t gfp_flags = GFP_KERNEL_ACCOUNT | __GFP_ZERO | gfp_extra_flags;
 	struct bpf_prog *fp;
-	u32 pages, delta;
-	int ret;
+	u32 pages;
 
 	size = round_up(size, PAGE_SIZE);
 	pages = size / PAGE_SIZE;
 	if (pages <= fp_old->pages)
 		return fp_old;
 
-	delta = pages - fp_old->pages;
-	ret = __bpf_prog_charge(fp_old->aux->user, delta);
-	if (ret)
-		return NULL;
-
 	fp = __vmalloc(size, gfp_flags);
-	if (fp == NULL) {
-		__bpf_prog_uncharge(fp_old->aux->user, delta);
-	} else {
+	if (fp) {
 		memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
 		fp->pages = pages;
 		fp->aux->prog = fp;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 29096d96d989..d16dd4945100 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -1632,51 +1632,6 @@ static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
 	audit_log_end(ab);
 }
 
-int __bpf_prog_charge(struct user_struct *user, u32 pages)
-{
-	unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
-	unsigned long user_bufs;
-
-	if (user) {
-		user_bufs = atomic_long_add_return(pages, &user->locked_vm);
-		if (user_bufs > memlock_limit) {
-			atomic_long_sub(pages, &user->locked_vm);
-			return -EPERM;
-		}
-	}
-
-	return 0;
-}
-
-void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
-{
-	if (user)
-		atomic_long_sub(pages, &user->locked_vm);
-}
-
-static int bpf_prog_charge_memlock(struct bpf_prog *prog)
-{
-	struct user_struct *user = get_current_user();
-	int ret;
-
-	ret = __bpf_prog_charge(user, prog->pages);
-	if (ret) {
-		free_uid(user);
-		return ret;
-	}
-
-	prog->aux->user = user;
-	return 0;
-}
-
-static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
-{
-	struct user_struct *user = prog->aux->user;
-
-	__bpf_prog_uncharge(user, prog->pages);
-	free_uid(user);
-}
-
 static int bpf_prog_alloc_id(struct bpf_prog *prog)
 {
 	int id;
@@ -1726,7 +1681,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu)
 
 	kvfree(aux->func_info);
 	kfree(aux->func_info_aux);
-	bpf_prog_uncharge_memlock(aux->prog);
+	free_uid(aux->user);
 	security_bpf_prog_free(aux);
 	bpf_prog_free(aux->prog);
 }
@@ -2164,7 +2119,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
 		if (IS_ERR(dst_prog)) {
 			err = PTR_ERR(dst_prog);
-			goto free_prog_nouncharge;
+			goto free_prog;
 		}
 		prog->aux->dst_prog = dst_prog;
 	}
@@ -2174,18 +2129,15 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
 
 	err = security_bpf_prog_alloc(prog->aux);
 	if (err)
-		goto free_prog_nouncharge;
-
-	err = bpf_prog_charge_memlock(prog);
-	if (err)
-		goto free_prog_sec;
+		goto free_prog;
 
+	prog->aux->user = get_current_user();
 	prog->len = attr->insn_cnt;
 
 	err = -EFAULT;
 	if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
 			   bpf_prog_insn_size(prog)) != 0)
-		goto free_prog;
+		goto free_prog_sec;
 
 	prog->orig_prog = NULL;
 	prog->jited = 0;
@@ -2196,19 +2148,19 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
 	if (bpf_prog_is_dev_bound(prog->aux)) {
 		err = bpf_prog_offload_init(prog, attr);
 		if (err)
-			goto free_prog;
+			goto free_prog_sec;
 	}
 
 	/* find program type: socket_filter vs tracing_filter */
 	err = find_prog_type(type, prog);
 	if (err < 0)
-		goto free_prog;
+		goto free_prog_sec;
 
 	prog->aux->load_time = ktime_get_boottime_ns();
 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
 			       sizeof(attr->prog_name));
 	if (err < 0)
-		goto free_prog;
+		goto free_prog_sec;
 
 	/* run eBPF verifier */
 	err = bpf_check(&prog, attr, uattr);
@@ -2253,11 +2205,10 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
 	 */
 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
 	return err;
-free_prog:
-	bpf_prog_uncharge_memlock(prog);
 free_prog_sec:
+	free_uid(prog->aux->user);
 	security_bpf_prog_free(prog->aux);
-free_prog_nouncharge:
+free_prog:
 	bpf_prog_free(prog);
 	return err;
 }
-- 
2.26.2

[PATCH bpf-next v9 34/34] bpf: samples: do not touch RLIMIT_MEMLOCK

[Roman Gushchin]

Since bpf is not using rlimit memlock for the memory accounting
and control, do not change the limit in sample applications.

Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
---
 samples/bpf/map_perf_test_user.c    | 6 ------
 samples/bpf/offwaketime_user.c      | 6 ------
 samples/bpf/sockex2_user.c          | 2 --
 samples/bpf/sockex3_user.c          | 2 --
 samples/bpf/spintest_user.c         | 6 ------
 samples/bpf/syscall_tp_user.c       | 2 --
 samples/bpf/task_fd_query_user.c    | 6 ------
 samples/bpf/test_lru_dist.c         | 3 ---
 samples/bpf/test_map_in_map_user.c  | 6 ------
 samples/bpf/test_overhead_user.c    | 2 --
 samples/bpf/trace_event_user.c      | 2 --
 samples/bpf/tracex2_user.c          | 6 ------
 samples/bpf/tracex3_user.c          | 6 ------
 samples/bpf/tracex4_user.c          | 6 ------
 samples/bpf/tracex5_user.c          | 3 ---
 samples/bpf/tracex6_user.c          | 3 ---
 samples/bpf/xdp1_user.c             | 6 ------
 samples/bpf/xdp_adjust_tail_user.c  | 6 ------
 samples/bpf/xdp_monitor_user.c      | 5 -----
 samples/bpf/xdp_redirect_cpu_user.c | 6 ------
 samples/bpf/xdp_redirect_map_user.c | 6 ------
 samples/bpf/xdp_redirect_user.c     | 6 ------
 samples/bpf/xdp_router_ipv4_user.c  | 6 ------
 samples/bpf/xdp_rxq_info_user.c     | 6 ------
 samples/bpf/xdp_sample_pkts_user.c  | 6 ------
 samples/bpf/xdp_tx_iptunnel_user.c  | 6 ------
 samples/bpf/xdpsock_user.c          | 7 -------
 27 files changed, 133 deletions(-)

diff --git a/samples/bpf/map_perf_test_user.c b/samples/bpf/map_perf_test_user.c
index 8b13230b4c46..9db949290a78 100644
--- a/samples/bpf/map_perf_test_user.c
+++ b/samples/bpf/map_perf_test_user.c
@@ -421,7 +421,6 @@ static void fixup_map(struct bpf_object *obj)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	int nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
 	struct bpf_link *links[8];
 	struct bpf_program *prog;
@@ -430,11 +429,6 @@ int main(int argc, char **argv)
 	char filename[256];
 	int i = 0;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	if (argc > 1)
 		test_flags = atoi(argv[1]) ? : test_flags;
 
diff --git a/samples/bpf/offwaketime_user.c b/samples/bpf/offwaketime_user.c
index 5734cfdaaacb..73a986876c1a 100644
--- a/samples/bpf/offwaketime_user.c
+++ b/samples/bpf/offwaketime_user.c
@@ -95,18 +95,12 @@ static void int_exit(int sig)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_object *obj = NULL;
 	struct bpf_link *links[2];
 	struct bpf_program *prog;
 	int delay = 1, i = 0;
 	char filename[256];
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	if (load_kallsyms()) {
 		printf("failed to process /proc/kallsyms\n");
 		return 2;
diff --git a/samples/bpf/sockex2_user.c b/samples/bpf/sockex2_user.c
index af925a5afd1d..bafa567b840c 100644
--- a/samples/bpf/sockex2_user.c
+++ b/samples/bpf/sockex2_user.c
@@ -16,7 +16,6 @@ struct pair {
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_object *obj;
 	int map_fd, prog_fd;
 	char filename[256];
@@ -24,7 +23,6 @@ int main(int ac, char **argv)
 	FILE *f;
 
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
-	setrlimit(RLIMIT_MEMLOCK, &r);
 
 	if (bpf_prog_load(filename, BPF_PROG_TYPE_SOCKET_FILTER,
 			  &obj, &prog_fd))
diff --git a/samples/bpf/sockex3_user.c b/samples/bpf/sockex3_user.c
index 7793f6a6ae7e..6ae99ecc766c 100644
--- a/samples/bpf/sockex3_user.c
+++ b/samples/bpf/sockex3_user.c
@@ -26,7 +26,6 @@ struct pair {
 int main(int argc, char **argv)
 {
 	int i, sock, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd;
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_program *prog;
 	struct bpf_object *obj;
 	const char *section;
@@ -34,7 +33,6 @@ int main(int argc, char **argv)
 	FILE *f;
 
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
-	setrlimit(RLIMIT_MEMLOCK, &r);
 
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/spintest_user.c b/samples/bpf/spintest_user.c
index f090d0dc60d6..0d7e1e5a8658 100644
--- a/samples/bpf/spintest_user.c
+++ b/samples/bpf/spintest_user.c
@@ -10,7 +10,6 @@
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	char filename[256], symbol[256];
 	struct bpf_object *obj = NULL;
 	struct bpf_link *links[20];
@@ -20,11 +19,6 @@ int main(int ac, char **argv)
 	const char *section;
 	struct ksym *sym;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	if (load_kallsyms()) {
 		printf("failed to process /proc/kallsyms\n");
 		return 2;
diff --git a/samples/bpf/syscall_tp_user.c b/samples/bpf/syscall_tp_user.c
index 76a1d00128fb..a0ebf1833ed3 100644
--- a/samples/bpf/syscall_tp_user.c
+++ b/samples/bpf/syscall_tp_user.c
@@ -115,7 +115,6 @@ static int test(char *filename, int num_progs)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	int opt, num_progs = 1;
 	char filename[256];
 
@@ -131,7 +130,6 @@ int main(int argc, char **argv)
 		}
 	}
 
-	setrlimit(RLIMIT_MEMLOCK, &r);
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 
 	return test(filename, num_progs);
diff --git a/samples/bpf/task_fd_query_user.c b/samples/bpf/task_fd_query_user.c
index f6b772faa348..a78025b0026b 100644
--- a/samples/bpf/task_fd_query_user.c
+++ b/samples/bpf/task_fd_query_user.c
@@ -310,7 +310,6 @@ static int test_debug_fs_uprobe(char *binary_path, long offset, bool is_return)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	extern char __executable_start;
 	char filename[256], buf[256];
 	__u64 uprobe_file_offset;
@@ -318,11 +317,6 @@ int main(int argc, char **argv)
 	struct bpf_object *obj;
 	int i = 0, err = -1;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return err;
-	}
-
 	if (load_kallsyms()) {
 		printf("failed to process /proc/kallsyms\n");
 		return err;
diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index b313dba4111b..c92c5c06b965 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -489,7 +489,6 @@ static void test_parallel_lru_loss(int map_type, int map_flags, int nr_tasks)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	int map_flags[] = {0, BPF_F_NO_COMMON_LRU};
 	const char *dist_file;
 	int nr_tasks = 1;
@@ -508,8 +507,6 @@ int main(int argc, char **argv)
 
 	setbuf(stdout, NULL);
 
-	assert(!setrlimit(RLIMIT_MEMLOCK, &r));
-
 	srand(time(NULL));
 
 	nr_cpus = bpf_num_possible_cpus();
diff --git a/samples/bpf/test_map_in_map_user.c b/samples/bpf/test_map_in_map_user.c
index 98656de56b83..472d65c70354 100644
--- a/samples/bpf/test_map_in_map_user.c
+++ b/samples/bpf/test_map_in_map_user.c
@@ -114,17 +114,11 @@ static void test_map_in_map(void)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_link *link = NULL;
 	struct bpf_program *prog;
 	struct bpf_object *obj;
 	char filename[256];
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/test_overhead_user.c b/samples/bpf/test_overhead_user.c
index 819a6fe86f89..4821f9d99c1f 100644
--- a/samples/bpf/test_overhead_user.c
+++ b/samples/bpf/test_overhead_user.c
@@ -162,13 +162,11 @@ static void unload_progs(void)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	int num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
 	int test_flags = ~0;
 	char filename[256];
 	int err = 0;
 
-	setrlimit(RLIMIT_MEMLOCK, &r);
 
 	if (argc > 1)
 		test_flags = atoi(argv[1]) ? : test_flags;
diff --git a/samples/bpf/trace_event_user.c b/samples/bpf/trace_event_user.c
index ac1ba368195c..9664749bf618 100644
--- a/samples/bpf/trace_event_user.c
+++ b/samples/bpf/trace_event_user.c
@@ -294,13 +294,11 @@ static void test_bpf_perf_event(void)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_object *obj = NULL;
 	char filename[256];
 	int error = 1;
 
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
-	setrlimit(RLIMIT_MEMLOCK, &r);
 
 	signal(SIGINT, err_exit);
 	signal(SIGTERM, err_exit);
diff --git a/samples/bpf/tracex2_user.c b/samples/bpf/tracex2_user.c
index 3d6eab711d23..1626d51dfffd 100644
--- a/samples/bpf/tracex2_user.c
+++ b/samples/bpf/tracex2_user.c
@@ -116,7 +116,6 @@ static void int_exit(int sig)
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	long key, next_key, value;
 	struct bpf_link *links[2];
 	struct bpf_program *prog;
@@ -125,11 +124,6 @@ int main(int ac, char **argv)
 	int i, j = 0;
 	FILE *f;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex3_user.c b/samples/bpf/tracex3_user.c
index 83e0fecbb01a..33e16ba39f25 100644
--- a/samples/bpf/tracex3_user.c
+++ b/samples/bpf/tracex3_user.c
@@ -107,7 +107,6 @@ static void print_hist(int fd)
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_link *links[2];
 	struct bpf_program *prog;
 	struct bpf_object *obj;
@@ -127,11 +126,6 @@ int main(int ac, char **argv)
 		}
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex4_user.c b/samples/bpf/tracex4_user.c
index e8faf8f184ae..cea399424bca 100644
--- a/samples/bpf/tracex4_user.c
+++ b/samples/bpf/tracex4_user.c
@@ -48,18 +48,12 @@ static void print_old_objects(int fd)
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_link *links[2];
 	struct bpf_program *prog;
 	struct bpf_object *obj;
 	char filename[256];
 	int map_fd, i, j = 0;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
-		return 1;
-	}
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex5_user.c b/samples/bpf/tracex5_user.c
index c17d3fb5fd64..08dfdc77ad2a 100644
--- a/samples/bpf/tracex5_user.c
+++ b/samples/bpf/tracex5_user.c
@@ -34,7 +34,6 @@ static void install_accept_all_seccomp(void)
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_link *link = NULL;
 	struct bpf_program *prog;
 	struct bpf_object *obj;
@@ -43,8 +42,6 @@ int main(int ac, char **argv)
 	char filename[256];
 	FILE *f;
 
-	setrlimit(RLIMIT_MEMLOCK, &r);
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/tracex6_user.c b/samples/bpf/tracex6_user.c
index 33df9784775d..28296f40c133 100644
--- a/samples/bpf/tracex6_user.c
+++ b/samples/bpf/tracex6_user.c
@@ -175,15 +175,12 @@ static void test_bpf_perf_event(void)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_link *links[2];
 	struct bpf_program *prog;
 	struct bpf_object *obj;
 	char filename[256];
 	int i = 0;
 
-	setrlimit(RLIMIT_MEMLOCK, &r);
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	obj = bpf_object__open_file(filename, NULL);
 	if (libbpf_get_error(obj)) {
diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index c447ad9e3a1d..116e39f6b666 100644
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -79,7 +79,6 @@ static void usage(const char *prog)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -117,11 +116,6 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	ifindex = if_nametoindex(argv[optind]);
 	if (!ifindex) {
 		perror("if_nametoindex");
diff --git a/samples/bpf/xdp_adjust_tail_user.c b/samples/bpf/xdp_adjust_tail_user.c
index ba482dc3da33..a70b094c8ec5 100644
--- a/samples/bpf/xdp_adjust_tail_user.c
+++ b/samples/bpf/xdp_adjust_tail_user.c
@@ -82,7 +82,6 @@ static void usage(const char *cmd)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -143,11 +142,6 @@ int main(int argc, char **argv)
 		}
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
-		return 1;
-	}
-
 	if (!ifindex) {
 		fprintf(stderr, "Invalid ifname\n");
 		return 1;
diff --git a/samples/bpf/xdp_monitor_user.c b/samples/bpf/xdp_monitor_user.c
index 03d0a182913f..49ebc49aefc3 100644
--- a/samples/bpf/xdp_monitor_user.c
+++ b/samples/bpf/xdp_monitor_user.c
@@ -687,7 +687,6 @@ static void print_bpf_prog_info(void)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_program *prog;
 	int longindex = 0, opt;
 	int ret = EXIT_FAILURE;
@@ -719,10 +718,6 @@ int main(int argc, char **argv)
 	}
 
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return ret;
-	}
 
 	/* Remove tracepoint program when program is interrupted or killed */
 	signal(SIGINT, int_exit);
diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index f78cb18319aa..576411612523 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -765,7 +765,6 @@ static int load_cpumap_prog(char *file_name, char *prog_name,
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	char *prog_name = "xdp_cpu_map5_lb_hash_ip_pairs";
 	char *mprog_filename = "xdp_redirect_kern.o";
 	char *redir_interface = NULL, *redir_map = NULL;
@@ -804,11 +803,6 @@ int main(int argc, char **argv)
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	prog_load_attr.file = filename;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
 		return err;
 
diff --git a/samples/bpf/xdp_redirect_map_user.c b/samples/bpf/xdp_redirect_map_user.c
index 35e16dee613e..31131b6e7782 100644
--- a/samples/bpf/xdp_redirect_map_user.c
+++ b/samples/bpf/xdp_redirect_map_user.c
@@ -96,7 +96,6 @@ static void usage(const char *prog)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -135,11 +134,6 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	ifindex_in = if_nametoindex(argv[optind]);
 	if (!ifindex_in)
 		ifindex_in = strtoul(argv[optind], NULL, 0);
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c
index 9ca2bf457cda..41d705c3a1f7 100644
--- a/samples/bpf/xdp_redirect_user.c
+++ b/samples/bpf/xdp_redirect_user.c
@@ -97,7 +97,6 @@ static void usage(const char *prog)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -136,11 +135,6 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	ifindex_in = if_nametoindex(argv[optind]);
 	if (!ifindex_in)
 		ifindex_in = strtoul(argv[optind], NULL, 0);
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
index c2da1b51ff95..b5f03cb17a3c 100644
--- a/samples/bpf/xdp_router_ipv4_user.c
+++ b/samples/bpf/xdp_router_ipv4_user.c
@@ -625,7 +625,6 @@ static void usage(const char *prog)
 
 int main(int ac, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -670,11 +669,6 @@ int main(int ac, char **argv)
 		return 1;
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
 		return 1;
 
diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c
index 93fa1bc54f13..74a2926eba08 100644
--- a/samples/bpf/xdp_rxq_info_user.c
+++ b/samples/bpf/xdp_rxq_info_user.c
@@ -450,7 +450,6 @@ static void stats_poll(int interval, int action, __u32 cfg_opt)
 int main(int argc, char **argv)
 {
 	__u32 cfg_options= NO_TOUCH ; /* Default: Don't touch packet memory */
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -474,11 +473,6 @@ int main(int argc, char **argv)
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	prog_load_attr.file = filename;
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
 		return EXIT_FAIL;
 
diff --git a/samples/bpf/xdp_sample_pkts_user.c b/samples/bpf/xdp_sample_pkts_user.c
index 4b2a300c750c..706475e004cb 100644
--- a/samples/bpf/xdp_sample_pkts_user.c
+++ b/samples/bpf/xdp_sample_pkts_user.c
@@ -109,7 +109,6 @@ static void usage(const char *prog)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
@@ -143,11 +142,6 @@ int main(int argc, char **argv)
 		return 1;
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK)");
-		return 1;
-	}
-
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 	prog_load_attr.file = filename;
 
diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
index a419bee151a8..1d4f305d02aa 100644
--- a/samples/bpf/xdp_tx_iptunnel_user.c
+++ b/samples/bpf/xdp_tx_iptunnel_user.c
@@ -155,7 +155,6 @@ int main(int argc, char **argv)
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	int min_port = 0, max_port = 0, vip2tnl_map_fd;
 	const char *optstr = "i:a:p:s:d:m:T:P:FSNh";
 	unsigned char opt_flags[256] = {};
@@ -254,11 +253,6 @@ int main(int argc, char **argv)
 		}
 	}
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
-		return 1;
-	}
-
 	if (!ifindex) {
 		fprintf(stderr, "Invalid ifname\n");
 		return 1;
diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
index 036bd019e400..909f77647deb 100644
--- a/samples/bpf/xdpsock_user.c
+++ b/samples/bpf/xdpsock_user.c
@@ -1489,7 +1489,6 @@ static void apply_setsockopt(struct xsk_socket_info *xsk)
 
 int main(int argc, char **argv)
 {
-	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	bool rx = false, tx = false;
 	struct xsk_umem_info *umem;
 	struct bpf_object *obj;
@@ -1499,12 +1498,6 @@ int main(int argc, char **argv)
 
 	parse_command_line(argc, argv);
 
-	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
-		fprintf(stderr, "ERROR: setrlimit(RLIMIT_MEMLOCK) \"%s\"\n",
-			strerror(errno));
-		exit(EXIT_FAILURE);
-	}
-
 	if (opt_num_xsks > 1)
 		load_xdp_program(argv, &obj);
 
-- 
2.26.2

Re: [PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[patchwork-bot+netdevbpf]

Hello:

This series was applied to bpf/bpf-next.git (refs/heads/master):

On Tue, 1 Dec 2020 13:58:26 -0800 you wrote:
> Currently bpf is using the memlock rlimit for the memory accounting.
> This approach has its downsides and over time has created a significant
> amount of problems:
> 
> 1) The limit is per-user, but because most bpf operations are performed
>    as root, the limit has a little value.
> 
> [...]

Here is the summary with links:
  - [bpf-next,v9,01/34] mm: memcontrol: use helpers to read page's memcg data
    https://git.kernel.org/bpf/bpf-next/c/bcfe06bf2622
  - [bpf-next,v9,02/34] mm: memcontrol/slab: use helpers to access slab page's memcg_data
    https://git.kernel.org/bpf/bpf-next/c/270c6a71460e
  - [bpf-next,v9,03/34] mm: introduce page memcg flags
    https://git.kernel.org/bpf/bpf-next/c/87944e2992bd
  - [bpf-next,v9,04/34] mm: convert page kmemcg type to a page memcg flag
    https://git.kernel.org/bpf/bpf-next/c/18b2db3b0385
  - [bpf-next,v9,05/34] bpf: memcg-based memory accounting for bpf progs
    https://git.kernel.org/bpf/bpf-next/c/ddf8503c7c43
  - [bpf-next,v9,06/34] bpf: prepare for memcg-based memory accounting for bpf maps
    https://git.kernel.org/bpf/bpf-next/c/48edc1f78aab
  - [bpf-next,v9,07/34] bpf: memcg-based memory accounting for bpf maps
    https://git.kernel.org/bpf/bpf-next/c/d5299b67dd59
  - [bpf-next,v9,08/34] bpf: refine memcg-based memory accounting for arraymap maps
    https://git.kernel.org/bpf/bpf-next/c/6d192c7938b7
  - [bpf-next,v9,09/34] bpf: refine memcg-based memory accounting for cpumap maps
    https://git.kernel.org/bpf/bpf-next/c/e88cc05b61f3
  - [bpf-next,v9,10/34] bpf: memcg-based memory accounting for cgroup storage maps
    https://git.kernel.org/bpf/bpf-next/c/3a61c7c58b30
  - [bpf-next,v9,11/34] bpf: refine memcg-based memory accounting for devmap maps
    https://git.kernel.org/bpf/bpf-next/c/1440290adf7b
  - [bpf-next,v9,12/34] bpf: refine memcg-based memory accounting for hashtab maps
    https://git.kernel.org/bpf/bpf-next/c/881456811a33
  - [bpf-next,v9,13/34] bpf: memcg-based memory accounting for lpm_trie maps
    https://git.kernel.org/bpf/bpf-next/c/353e7af4bf5e
  - [bpf-next,v9,14/34] bpf: memcg-based memory accounting for bpf ringbuffer
    https://git.kernel.org/bpf/bpf-next/c/be4035c734d1
  - [bpf-next,v9,15/34] bpf: memcg-based memory accounting for bpf local storage maps
    https://git.kernel.org/bpf/bpf-next/c/e9aae8beba82
  - [bpf-next,v9,16/34] bpf: refine memcg-based memory accounting for sockmap and sockhash maps
    https://git.kernel.org/bpf/bpf-next/c/7846dd9f835e
  - [bpf-next,v9,17/34] bpf: refine memcg-based memory accounting for xskmap maps
    https://git.kernel.org/bpf/bpf-next/c/28e1dcdef0cb
  - [bpf-next,v9,18/34] bpf: eliminate rlimit-based memory accounting for arraymap maps
    https://git.kernel.org/bpf/bpf-next/c/1bc5975613ed
  - [bpf-next,v9,19/34] bpf: eliminate rlimit-based memory accounting for bpf_struct_ops maps
    https://git.kernel.org/bpf/bpf-next/c/f043733f31e5
  - [bpf-next,v9,20/34] bpf: eliminate rlimit-based memory accounting for cpumap maps
    https://git.kernel.org/bpf/bpf-next/c/711cabaf1432
  - [bpf-next,v9,21/34] bpf: eliminate rlimit-based memory accounting for cgroup storage maps
    https://git.kernel.org/bpf/bpf-next/c/087b0d39fe22
  - [bpf-next,v9,22/34] bpf: eliminate rlimit-based memory accounting for devmap maps
    https://git.kernel.org/bpf/bpf-next/c/844f157f6c0a
  - [bpf-next,v9,23/34] bpf: eliminate rlimit-based memory accounting for hashtab maps
    https://git.kernel.org/bpf/bpf-next/c/755e5d55367a
  - [bpf-next,v9,24/34] bpf: eliminate rlimit-based memory accounting for lpm_trie maps
    https://git.kernel.org/bpf/bpf-next/c/cbddcb574d41
  - [bpf-next,v9,25/34] bpf: eliminate rlimit-based memory accounting for queue_stack_maps maps
    https://git.kernel.org/bpf/bpf-next/c/a37fb7ef24a4
  - [bpf-next,v9,26/34] bpf: eliminate rlimit-based memory accounting for reuseport_array maps
    https://git.kernel.org/bpf/bpf-next/c/db54330d3e13
  - [bpf-next,v9,27/34] bpf: eliminate rlimit-based memory accounting for bpf ringbuffer
    https://git.kernel.org/bpf/bpf-next/c/abbdd0813f34
  - [bpf-next,v9,28/34] bpf: eliminate rlimit-based memory accounting for sockmap and sockhash maps
    https://git.kernel.org/bpf/bpf-next/c/0d2c4f964050
  - [bpf-next,v9,29/34] bpf: eliminate rlimit-based memory accounting for stackmap maps
    https://git.kernel.org/bpf/bpf-next/c/370868107bf6
  - [bpf-next,v9,30/34] bpf: eliminate rlimit-based memory accounting for xskmap maps
    https://git.kernel.org/bpf/bpf-next/c/819a4f323579
  - [bpf-next,v9,31/34] bpf: eliminate rlimit-based memory accounting for bpf local storage maps
    https://git.kernel.org/bpf/bpf-next/c/ab31be378a63
  - [bpf-next,v9,32/34] bpf: eliminate rlimit-based memory accounting infra for bpf maps
    https://git.kernel.org/bpf/bpf-next/c/80ee81e0403c
  - [bpf-next,v9,33/34] bpf: eliminate rlimit-based memory accounting for bpf progs
    https://git.kernel.org/bpf/bpf-next/c/3ac1f01b43b6
  - [bpf-next,v9,34/34] bpf: samples: do not touch RLIMIT_MEMLOCK
    https://git.kernel.org/bpf/bpf-next/c/5b0764b2d345

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[Alexei Starovoitov]

On Tue, Dec 1, 2020 at 1:59 PM Roman Gushchin <guro@fb.com> wrote:
>
> 5) Cryptic -EPERM is returned on exceeding the limit. Libbpf even had
>    a function to "explain" this case for users.
...
> v9:
>   - always charge the saved memory cgroup, by Daniel, Toke and Alexei
>   - added bpf_map_kzalloc()
>   - rebase and minor fixes

This looks great. Applied.
Please follow up with a change to libbpf's pr_perm_msg().
That helpful warning should stay for old kernels, but it would be
misleading for new kernels.
libbpf probably needs a feature check to make this warning conditional.

Thanks!

Re: [PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[Roman Gushchin]

On Wed, Dec 02, 2020 at 06:54:46PM -0800, Alexei Starovoitov wrote:
> On Tue, Dec 1, 2020 at 1:59 PM Roman Gushchin <guro@fb.com> wrote:
> >
> > 5) Cryptic -EPERM is returned on exceeding the limit. Libbpf even had
> >    a function to "explain" this case for users.
> ...
> > v9:
> >   - always charge the saved memory cgroup, by Daniel, Toke and Alexei
> >   - added bpf_map_kzalloc()
> >   - rebase and minor fixes
> 
> This looks great. Applied.

Thanks!

> Please follow up with a change to libbpf's pr_perm_msg().
> That helpful warning should stay for old kernels, but it would be
> misleading for new kernels.
> libbpf probably needs a feature check to make this warning conditional.

I think we've discussed it several months ago and at that time we didn't
find a good way to check this feature. I'll think again, but if somebody
has any ideas here, I'll appreciate a lot.

Re: [PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[Daniel Borkmann]

On 12/3/20 4:26 AM, Roman Gushchin wrote:
> On Wed, Dec 02, 2020 at 06:54:46PM -0800, Alexei Starovoitov wrote:
>> On Tue, Dec 1, 2020 at 1:59 PM Roman Gushchin <guro@fb.com> wrote:
>>>
>>> 5) Cryptic -EPERM is returned on exceeding the limit. Libbpf even had
>>>     a function to "explain" this case for users.
>> ...
>>> v9:
>>>    - always charge the saved memory cgroup, by Daniel, Toke and Alexei
>>>    - added bpf_map_kzalloc()
>>>    - rebase and minor fixes
>>
>> This looks great. Applied.
> 
> Thanks!
> 
>> Please follow up with a change to libbpf's pr_perm_msg().
>> That helpful warning should stay for old kernels, but it would be
>> misleading for new kernels.
>> libbpf probably needs a feature check to make this warning conditional.
> 
> I think we've discussed it several months ago and at that time we didn't
> find a good way to check this feature. I'll think again, but if somebody
> has any ideas here, I'll appreciate a lot.

Hm, bit tricky, agree .. given we only throw the warning in pr_perm_msg() for
non-root and thus probing options are also limited, otherwise just probing for
a helper that was added in this same cycle would have been good enough as a
simple heuristic. I wonder if it would make sense to add some hint inside the
bpf_{prog,map}_show_fdinfo() to indicate that accounting with memcg is enabled
for the prog/map one way or another? Not just for the sake of pr_perm_msg(), but
in general for apps to stop messing with rlimit at this point. Maybe also bpftool
feature probe could be extended to indicate that as well (e.g. the json output
can be fed into Go natively).

Re: [PATCH bpf-next v9 00/34] bpf: switch to memcg-based memory accounting

[Andrii Nakryiko]

On Fri, Dec 4, 2020 at 4:37 PM Daniel Borkmann <daniel@iogearbox.net> wrote:
>
> On 12/3/20 4:26 AM, Roman Gushchin wrote:
> > On Wed, Dec 02, 2020 at 06:54:46PM -0800, Alexei Starovoitov wrote:
> >> On Tue, Dec 1, 2020 at 1:59 PM Roman Gushchin <guro@fb.com> wrote:
> >>>
> >>> 5) Cryptic -EPERM is returned on exceeding the limit. Libbpf even had
> >>>     a function to "explain" this case for users.
> >> ...
> >>> v9:
> >>>    - always charge the saved memory cgroup, by Daniel, Toke and Alexei
> >>>    - added bpf_map_kzalloc()
> >>>    - rebase and minor fixes
> >>
> >> This looks great. Applied.
> >
> > Thanks!
> >
> >> Please follow up with a change to libbpf's pr_perm_msg().
> >> That helpful warning should stay for old kernels, but it would be
> >> misleading for new kernels.
> >> libbpf probably needs a feature check to make this warning conditional.
> >
> > I think we've discussed it several months ago and at that time we didn't
> > find a good way to check this feature. I'll think again, but if somebody
> > has any ideas here, I'll appreciate a lot.
>
> Hm, bit tricky, agree .. given we only throw the warning in pr_perm_msg() for
> non-root and thus probing options are also limited, otherwise just probing for
> a helper that was added in this same cycle would have been good enough as a
> simple heuristic. I wonder if it would make sense to add some hint inside the
> bpf_{prog,map}_show_fdinfo() to indicate that accounting with memcg is enabled

I think the initial version was emitting 0 for memlock, so that was a
pretty simple way to prove stuff. But I think it was changed at the
last minute to emit some non-zero "estimate" of memory used or
something like that?

> for the prog/map one way or another? Not just for the sake of pr_perm_msg(), but
> in general for apps to stop messing with rlimit at this point. Maybe also bpftool
> feature probe could be extended to indicate that as well (e.g. the json output
> can be fed into Go natively).