kselftests: cgroup: add perpcu memory accounting test (90631e1d) · Commits · 戴 / test

tools/testing/selftests/cgroup/test_kmem.c

+69 −1

Original line number	Diff line number	Diff line
		@@ -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(const char *root)
		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

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