The patch titled
Subject: kselftests: cgroup: add perpcu memory accounting test
has been removed from the -mm tree. Its filename was
kselftests-cgroup-add-perpcu-memory-accounting-test.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Roman Gushchin <guro@xxxxxx>
Subject: kselftests: cgroup: add perpcu memory accounting test
Add a simple test to check the percpu memory accounting. The test creates
a cgroup tree with 1000 child cgroups and checks values of memory.current
and memory.stat::percpu.
Link: http://lkml.kernel.org/r/20200608230819.832349-6-guro@xxxxxx
Signed-off-by: Roman Gushchin <guro@xxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Tobin C. Harding <tobin@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Waiman Long <longman@xxxxxxxxxx>
Cc: Michal Koutný <mkoutny@xxxxxxxx>
Cc: Bixuan Cui <cuibixuan@xxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/cgroup/test_kmem.c | 70 ++++++++++++++++++-
1 file changed, 69 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/cgroup/test_kmem.c~kselftests-cgroup-add-perpcu-memory-accounting-test
+++ a/tools/testing/selftests/cgroup/test_kmem.c
@@ -18,6 +18,15 @@
#include "cgroup_util.h"
+/*
+ * Memory cgroup charging and vmstat data aggregation is performed using
+ * percpu batches 32 pages big (look at MEMCG_CHARGE_BATCH). So the maximum
+ * discrepancy between charge and vmstat entries is number of cpus multiplied
+ * by 32 pages multiplied by 2.
+ */
+#define MAX_VMSTAT_ERROR (4096 * 32 * 2 * get_nprocs())
+
+
static int alloc_dcache(const char *cgroup, void *arg)
{
unsigned long i;
@@ -180,7 +189,7 @@ static int test_kmem_memcg_deletion(cons
goto cleanup;
sum = slab + anon + file + kernel_stack;
- if (abs(sum - current) < 4096 * 32 * 2 * get_nprocs()) {
+ if (abs(sum - current) < MAX_VMSTAT_ERROR) {
ret = KSFT_PASS;
} else {
printf("memory.current = %ld\n", current);
@@ -331,6 +340,64 @@ cleanup:
return ret;
}
+/*
+ * This test creates a sub-tree with 1000 memory cgroups.
+ * Then it checks that the memory.current on the parent level
+ * is greater than 0 and approximates matches the percpu value
+ * from memory.stat.
+ */
+static int test_percpu_basic(const char *root)
+{
+ int ret = KSFT_FAIL;
+ char *parent, *child;
+ long current, percpu;
+ int i;
+
+ parent = cg_name(root, "percpu_basic_test");
+ if (!parent)
+ goto cleanup;
+
+ if (cg_create(parent))
+ goto cleanup;
+
+ if (cg_write(parent, "cgroup.subtree_control", "+memory"))
+ goto cleanup;
+
+ for (i = 0; i < 1000; i++) {
+ child = cg_name_indexed(parent, "child", i);
+ if (!child)
+ return -1;
+
+ if (cg_create(child))
+ goto cleanup_children;
+
+ free(child);
+ }
+
+ current = cg_read_long(parent, "memory.current");
+ percpu = cg_read_key_long(parent, "memory.stat", "percpu ");
+
+ if (current > 0 && percpu > 0 && abs(current - percpu) <
+ MAX_VMSTAT_ERROR)
+ ret = KSFT_PASS;
+ else
+ printf("memory.current %ld\npercpu %ld\n",
+ current, percpu);
+
+cleanup_children:
+ for (i = 0; i < 1000; i++) {
+ child = cg_name_indexed(parent, "child", i);
+ cg_destroy(child);
+ free(child);
+ }
+
+cleanup:
+ cg_destroy(parent);
+ free(parent);
+
+ return ret;
+}
+
#define T(x) { x, #x }
struct kmem_test {
int (*fn)(const char *root);
@@ -341,6 +408,7 @@ struct kmem_test {
T(test_kmem_proc_kpagecgroup),
T(test_kmem_kernel_stacks),
T(test_kmem_dead_cgroups),
+ T(test_percpu_basic),
};
#undef T
_
Patches currently in -mm which might be from guro@xxxxxx are
mm-vmstat-fix-proc-sys-vm-stat_refresh-generating-false-warnings.patch
mm-vmstat-fix-proc-sys-vm-stat_refresh-generating-false-warnings-fix.patch
