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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /tools/perf/util/lock-contention.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'tools/perf/util/lock-contention.c')
-rw-r--r--tools/perf/util/lock-contention.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/tools/perf/util/lock-contention.c b/tools/perf/util/lock-contention.c
new file mode 100644
index 000000000..119a7206f
--- /dev/null
+++ b/tools/perf/util/lock-contention.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "debug.h"
+#include "env.h"
+#include "lock-contention.h"
+#include "machine.h"
+#include "symbol.h"
+
+#include <limits.h>
+#include <string.h>
+
+#include <linux/hash.h>
+#include <linux/zalloc.h>
+
+#define __lockhashfn(key) hash_long((unsigned long)key, LOCKHASH_BITS)
+#define lockhashentry(key) (lockhash_table + __lockhashfn((key)))
+
+struct callstack_filter {
+ struct list_head list;
+ char name[];
+};
+
+static LIST_HEAD(callstack_filters);
+struct hlist_head *lockhash_table;
+
+int parse_call_stack(const struct option *opt __maybe_unused, const char *str,
+ int unset __maybe_unused)
+{
+ char *s, *tmp, *tok;
+ int ret = 0;
+
+ s = strdup(str);
+ if (s == NULL)
+ return -1;
+
+ for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) {
+ struct callstack_filter *entry;
+
+ entry = malloc(sizeof(*entry) + strlen(tok) + 1);
+ if (entry == NULL) {
+ pr_err("Memory allocation failure\n");
+ free(s);
+ return -1;
+ }
+
+ strcpy(entry->name, tok);
+ list_add_tail(&entry->list, &callstack_filters);
+ }
+
+ free(s);
+ return ret;
+}
+
+bool needs_callstack(void)
+{
+ return !list_empty(&callstack_filters);
+}
+
+struct lock_stat *lock_stat_find(u64 addr)
+{
+ struct hlist_head *entry = lockhashentry(addr);
+ struct lock_stat *ret;
+
+ hlist_for_each_entry(ret, entry, hash_entry) {
+ if (ret->addr == addr)
+ return ret;
+ }
+ return NULL;
+}
+
+struct lock_stat *lock_stat_findnew(u64 addr, const char *name, int flags)
+{
+ struct hlist_head *entry = lockhashentry(addr);
+ struct lock_stat *ret, *new;
+
+ hlist_for_each_entry(ret, entry, hash_entry) {
+ if (ret->addr == addr)
+ return ret;
+ }
+
+ new = zalloc(sizeof(struct lock_stat));
+ if (!new)
+ goto alloc_failed;
+
+ new->addr = addr;
+ new->name = strdup(name);
+ if (!new->name) {
+ free(new);
+ goto alloc_failed;
+ }
+
+ new->flags = flags;
+ new->wait_time_min = ULLONG_MAX;
+
+ hlist_add_head(&new->hash_entry, entry);
+ return new;
+
+alloc_failed:
+ pr_err("memory allocation failed\n");
+ return NULL;
+}
+
+bool match_callstack_filter(struct machine *machine, u64 *callstack, int max_stack_depth)
+{
+ struct map *kmap;
+ struct symbol *sym;
+ u64 ip;
+ uint16_t e_machine = perf_env__e_machine(machine->env, /*e_flags=*/NULL);
+ bool is_powerpc = e_machine == EM_PPC64 || e_machine == EM_PPC;
+
+ if (list_empty(&callstack_filters))
+ return true;
+
+ for (int i = 0; i < max_stack_depth; i++) {
+ struct callstack_filter *filter;
+
+ /*
+ * In powerpc, the callchain saved by kernel always includes
+ * first three entries as the NIP (next instruction pointer),
+ * LR (link register), and the contents of LR save area in the
+ * second stack frame. In certain scenarios its possible to have
+ * invalid kernel instruction addresses in either LR or the second
+ * stack frame's LR. In that case, kernel will store that address as
+ * zero.
+ *
+ * The below check will continue to look into callstack,
+ * incase first or second callstack index entry has 0
+ * address for powerpc.
+ */
+ if (!callstack || (!callstack[i] && (!is_powerpc || (i != 1 && i != 2))))
+ break;
+
+ ip = callstack[i];
+ sym = machine__find_kernel_symbol(machine, ip, &kmap);
+ if (sym == NULL)
+ continue;
+
+ list_for_each_entry(filter, &callstack_filters, list) {
+ if (strstr(sym->name, filter->name))
+ return true;
+ }
+ }
+ return false;
+}