From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- drivers/interconnect/icc-kunit.c | 324 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 324 insertions(+) create mode 100644 drivers/interconnect/icc-kunit.c (limited to 'drivers/interconnect/icc-kunit.c') diff --git a/drivers/interconnect/icc-kunit.c b/drivers/interconnect/icc-kunit.c new file mode 100644 index 000000000..bad2b5837 --- /dev/null +++ b/drivers/interconnect/icc-kunit.c @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit tests for the Interconnect framework. + * + * Copyright (c) 2025 Kuan-Wei Chiu + * + * This suite verifies the behavior of the interconnect core, including + * topology construction, bandwidth aggregation, and path lifecycle. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "internal.h" + +enum { + NODE_CPU, + NODE_GPU, + NODE_BUS, + NODE_DDR, + NODE_MAX +}; + +struct test_node_data { + int id; + const char *name; + int num_links; + int links[2]; +}; + +/* + * Static Topology: + * CPU -\ + * -> BUS -> DDR + * GPU -/ + */ +static const struct test_node_data test_topology[] = { + { NODE_CPU, "cpu", 1, { NODE_BUS } }, + { NODE_GPU, "gpu", 1, { NODE_BUS } }, + { NODE_BUS, "bus", 1, { NODE_DDR } }, + { NODE_DDR, "ddr", 0, { } }, +}; + +struct icc_test_priv { + struct icc_provider provider; + struct platform_device *pdev; + struct icc_node *nodes[NODE_MAX]; +}; + +static struct icc_node *get_node(struct icc_test_priv *priv, int id) +{ + int idx = id - NODE_CPU; + + if (idx < 0 || idx >= ARRAY_SIZE(test_topology)) + return NULL; + return priv->nodes[idx]; +} + +static int icc_test_set(struct icc_node *src, struct icc_node *dst) +{ + return 0; +} + +static int icc_test_aggregate(struct icc_node *node, u32 tag, u32 avg_bw, + u32 peak_bw, u32 *agg_avg, u32 *agg_peak) +{ + return icc_std_aggregate(node, tag, avg_bw, peak_bw, agg_avg, agg_peak); +} + +static struct icc_node *icc_test_xlate(const struct of_phandle_args *spec, void *data) +{ + return NULL; +} + +static int icc_test_get_bw(struct icc_node *node, u32 *avg, u32 *peak) +{ + *avg = 0; + *peak = 0; + + return 0; +} + +static int icc_test_init(struct kunit *test) +{ + struct icc_test_priv *priv; + struct icc_node *node; + int i, j, ret; + + priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv); + test->priv = priv; + + priv->pdev = kunit_platform_device_alloc(test, "icc-test-dev", -1); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->pdev); + KUNIT_ASSERT_EQ(test, kunit_platform_device_add(test, priv->pdev), 0); + + priv->provider.set = icc_test_set; + priv->provider.aggregate = icc_test_aggregate; + priv->provider.xlate = icc_test_xlate; + priv->provider.get_bw = icc_test_get_bw; + priv->provider.dev = &priv->pdev->dev; + priv->provider.data = priv; + INIT_LIST_HEAD(&priv->provider.nodes); + + ret = icc_provider_register(&priv->provider); + KUNIT_ASSERT_EQ(test, ret, 0); + + for (i = 0; i < ARRAY_SIZE(test_topology); i++) { + const struct test_node_data *data = &test_topology[i]; + + node = icc_node_create(data->id); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, node); + + node->name = data->name; + icc_node_add(node, &priv->provider); + priv->nodes[i] = node; + } + + for (i = 0; i < ARRAY_SIZE(test_topology); i++) { + const struct test_node_data *data = &test_topology[i]; + struct icc_node *src = get_node(priv, data->id); + + for (j = 0; j < data->num_links; j++) { + ret = icc_link_create(src, data->links[j]); + KUNIT_ASSERT_EQ_MSG(test, ret, 0, "Failed to link %s->%d", + src->name, data->links[j]); + } + } + + icc_sync_state(&priv->pdev->dev); + + return 0; +} + +static void icc_test_exit(struct kunit *test) +{ + struct icc_test_priv *priv = test->priv; + + icc_nodes_remove(&priv->provider); + icc_provider_deregister(&priv->provider); +} + +/* + * Helper to construct a mock path. + * + * Because we are bypassing icc_get(), we must manually link the requests + * to the nodes' req_list so that icc_std_aggregate() can discover them. + */ +static struct icc_path *icc_test_create_path(struct kunit *test, + struct icc_node **nodes, int num) +{ + struct icc_path *path; + int i; + + path = kunit_kzalloc(test, struct_size(path, reqs, num), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, path); + + path->num_nodes = num; + for (i = 0; i < num; i++) { + path->reqs[i].node = nodes[i]; + hlist_add_head(&path->reqs[i].req_node, &nodes[i]->req_list); + } + path->name = "mock-path"; + + return path; +} + +static void icc_test_destroy_path(struct kunit *test, struct icc_path *path) +{ + int i; + + for (i = 0; i < path->num_nodes; i++) + hlist_del(&path->reqs[i].req_node); + + kunit_kfree(test, path); +} + +static void icc_test_topology_integrity(struct kunit *test) +{ + struct icc_test_priv *priv = test->priv; + struct icc_node *cpu = get_node(priv, NODE_CPU); + struct icc_node *bus = get_node(priv, NODE_BUS); + + KUNIT_EXPECT_EQ(test, cpu->num_links, 1); + KUNIT_EXPECT_PTR_EQ(test, cpu->links[0], bus); + KUNIT_EXPECT_PTR_EQ(test, cpu->provider, &priv->provider); +} + +static void icc_test_set_bw(struct kunit *test) +{ + struct icc_test_priv *priv = test->priv; + struct icc_path *path; + struct icc_node *path_nodes[3]; + int ret; + + /* Path: CPU -> BUS -> DDR */ + path_nodes[0] = get_node(priv, NODE_CPU); + path_nodes[1] = get_node(priv, NODE_BUS); + path_nodes[2] = get_node(priv, NODE_DDR); + + path = icc_test_create_path(test, path_nodes, 3); + + ret = icc_enable(path); + KUNIT_ASSERT_EQ(test, ret, 0); + + ret = icc_set_bw(path, 1000, 2000); + KUNIT_EXPECT_EQ(test, ret, 0); + + KUNIT_EXPECT_EQ(test, path_nodes[0]->avg_bw, 1000); + KUNIT_EXPECT_EQ(test, path_nodes[0]->peak_bw, 2000); + KUNIT_EXPECT_EQ(test, path_nodes[1]->avg_bw, 1000); + KUNIT_EXPECT_EQ(test, path_nodes[1]->peak_bw, 2000); + + icc_set_tag(path, 0xABC); + KUNIT_EXPECT_EQ(test, path->reqs[0].tag, 0xABC); + + icc_disable(path); + KUNIT_EXPECT_EQ(test, path_nodes[0]->avg_bw, 0); + + icc_test_destroy_path(test, path); +} + +static void icc_test_aggregation(struct kunit *test) +{ + struct icc_test_priv *priv = test->priv; + struct icc_path *path_cpu, *path_gpu; + struct icc_node *nodes_cpu[3], *nodes_gpu[2]; + struct icc_node *bus = get_node(priv, NODE_BUS); + int ret; + + nodes_cpu[0] = get_node(priv, NODE_CPU); + nodes_cpu[1] = bus; + nodes_cpu[2] = get_node(priv, NODE_DDR); + path_cpu = icc_test_create_path(test, nodes_cpu, 3); + + nodes_gpu[0] = get_node(priv, NODE_GPU); + nodes_gpu[1] = bus; + path_gpu = icc_test_create_path(test, nodes_gpu, 2); + + icc_enable(path_cpu); + icc_enable(path_gpu); + + ret = icc_set_bw(path_cpu, 1000, 1000); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, bus->avg_bw, 1000); + + ret = icc_set_bw(path_gpu, 2000, 2000); + KUNIT_EXPECT_EQ(test, ret, 0); + + /* Bus aggregates: CPU(1000) + GPU(2000) */ + KUNIT_EXPECT_EQ(test, bus->avg_bw, 3000); + /* Peak aggregates: max(CPU, GPU) */ + KUNIT_EXPECT_EQ(test, bus->peak_bw, 2000); + + icc_test_destroy_path(test, path_cpu); + icc_test_destroy_path(test, path_gpu); +} + +static void icc_test_bulk_ops(struct kunit *test) +{ + struct icc_test_priv *priv = test->priv; + struct icc_node *nodes_cpu[3], *nodes_gpu[2]; + struct icc_bulk_data bulk[2]; + int ret; + + nodes_cpu[0] = get_node(priv, NODE_CPU); + nodes_cpu[1] = get_node(priv, NODE_BUS); + nodes_cpu[2] = get_node(priv, NODE_DDR); + + nodes_gpu[0] = get_node(priv, NODE_GPU); + nodes_gpu[1] = get_node(priv, NODE_BUS); + + bulk[0].path = icc_test_create_path(test, nodes_cpu, 3); + bulk[0].avg_bw = 500; + bulk[0].peak_bw = 500; + + bulk[1].path = icc_test_create_path(test, nodes_gpu, 2); + bulk[1].avg_bw = 600; + bulk[1].peak_bw = 600; + + ret = icc_bulk_set_bw(2, bulk); + KUNIT_EXPECT_EQ(test, ret, 0); + /* Paths disabled, bandwidth should be 0 */ + KUNIT_EXPECT_EQ(test, get_node(priv, NODE_BUS)->avg_bw, 0); + + ret = icc_bulk_enable(2, bulk); + KUNIT_EXPECT_EQ(test, ret, 0); + /* Paths enabled, aggregation applies */ + KUNIT_EXPECT_EQ(test, get_node(priv, NODE_BUS)->avg_bw, 1100); + + icc_bulk_disable(2, bulk); + KUNIT_EXPECT_EQ(test, get_node(priv, NODE_BUS)->avg_bw, 0); + + icc_test_destroy_path(test, bulk[0].path); + icc_test_destroy_path(test, bulk[1].path); +} + +static struct kunit_case icc_test_cases[] = { + KUNIT_CASE(icc_test_topology_integrity), + KUNIT_CASE(icc_test_set_bw), + KUNIT_CASE(icc_test_aggregation), + KUNIT_CASE(icc_test_bulk_ops), + {} +}; + +static struct kunit_suite icc_test_suite = { + .name = "interconnect", + .init = icc_test_init, + .exit = icc_test_exit, + .test_cases = icc_test_cases, +}; + +kunit_test_suite(icc_test_suite); + +MODULE_AUTHOR("Kuan-Wei Chiu "); +MODULE_DESCRIPTION("KUnit tests for the Interconnect framework"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1