From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- tools/testing/radix-tree/benchmark.c | 150 +++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 tools/testing/radix-tree/benchmark.c (limited to 'tools/testing/radix-tree/benchmark.c') diff --git a/tools/testing/radix-tree/benchmark.c b/tools/testing/radix-tree/benchmark.c new file mode 100644 index 000000000..523c79f22 --- /dev/null +++ b/tools/testing/radix-tree/benchmark.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * benchmark.c: + * Author: Konstantin Khlebnikov + */ +#include +#include +#include +#include +#include "test.h" + +#define NSEC_PER_SEC 1000000000L + +static long long benchmark_iter(struct radix_tree_root *root, bool tagged) +{ + volatile unsigned long sink = 0; + struct radix_tree_iter iter; + struct timespec start, finish; + long long nsec; + int l, loops = 1; + void **slot; + +#ifdef BENCHMARK +again: +#endif + clock_gettime(CLOCK_MONOTONIC, &start); + for (l = 0; l < loops; l++) { + if (tagged) { + radix_tree_for_each_tagged(slot, root, &iter, 0, 0) + sink ^= (unsigned long)slot; + } else { + radix_tree_for_each_slot(slot, root, &iter, 0) + sink ^= (unsigned long)slot; + } + } + clock_gettime(CLOCK_MONOTONIC, &finish); + + nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC + + (finish.tv_nsec - start.tv_nsec); + +#ifdef BENCHMARK + if (loops == 1 && nsec * 5 < NSEC_PER_SEC) { + loops = NSEC_PER_SEC / nsec / 4 + 1; + goto again; + } +#endif + + nsec /= loops; + return nsec; +} + +static void benchmark_insert(struct radix_tree_root *root, + unsigned long size, unsigned long step) +{ + struct timespec start, finish; + unsigned long index; + long long nsec; + + clock_gettime(CLOCK_MONOTONIC, &start); + + for (index = 0 ; index < size ; index += step) + item_insert(root, index); + + clock_gettime(CLOCK_MONOTONIC, &finish); + + nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC + + (finish.tv_nsec - start.tv_nsec); + + printv(2, "Size: %8ld, step: %8ld, insertion: %15lld ns\n", + size, step, nsec); +} + +static void benchmark_tagging(struct radix_tree_root *root, + unsigned long size, unsigned long step) +{ + struct timespec start, finish; + unsigned long index; + long long nsec; + + clock_gettime(CLOCK_MONOTONIC, &start); + + for (index = 0 ; index < size ; index += step) + radix_tree_tag_set(root, index, 0); + + clock_gettime(CLOCK_MONOTONIC, &finish); + + nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC + + (finish.tv_nsec - start.tv_nsec); + + printv(2, "Size: %8ld, step: %8ld, tagging: %17lld ns\n", + size, step, nsec); +} + +static void benchmark_delete(struct radix_tree_root *root, + unsigned long size, unsigned long step) +{ + struct timespec start, finish; + unsigned long index; + long long nsec; + + clock_gettime(CLOCK_MONOTONIC, &start); + + for (index = 0 ; index < size ; index += step) + item_delete(root, index); + + clock_gettime(CLOCK_MONOTONIC, &finish); + + nsec = (finish.tv_sec - start.tv_sec) * NSEC_PER_SEC + + (finish.tv_nsec - start.tv_nsec); + + printv(2, "Size: %8ld, step: %8ld, deletion: %16lld ns\n", + size, step, nsec); +} + +static void benchmark_size(unsigned long size, unsigned long step) +{ + RADIX_TREE(tree, GFP_KERNEL); + long long normal, tagged; + + benchmark_insert(&tree, size, step); + benchmark_tagging(&tree, size, step); + + tagged = benchmark_iter(&tree, true); + normal = benchmark_iter(&tree, false); + + printv(2, "Size: %8ld, step: %8ld, tagged iteration: %8lld ns\n", + size, step, tagged); + printv(2, "Size: %8ld, step: %8ld, normal iteration: %8lld ns\n", + size, step, normal); + + benchmark_delete(&tree, size, step); + + item_kill_tree(&tree); + rcu_barrier(); +} + +void benchmark(void) +{ + unsigned long size[] = {1 << 10, 1 << 20, 0}; + unsigned long step[] = {1, 2, 7, 15, 63, 64, 65, + 128, 256, 512, 12345, 0}; + int c, s; + + printv(1, "starting benchmarks\n"); + printv(1, "RADIX_TREE_MAP_SHIFT = %d\n", RADIX_TREE_MAP_SHIFT); + + for (c = 0; size[c]; c++) + for (s = 0; step[s]; s++) + benchmark_size(size[c], step[s]); +} -- cgit v1.3.1