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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /tools/perf/util/thread.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'tools/perf/util/thread.c')
-rw-r--r--tools/perf/util/thread.c638
1 files changed, 638 insertions, 0 deletions
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
new file mode 100644
index 000000000..e483ffcb5
--- /dev/null
+++ b/tools/perf/util/thread.c
@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <elf.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <linux/kernel.h>
+#include <linux/zalloc.h>
+#include "dso.h"
+#include "session.h"
+#include "thread.h"
+#include "thread-stack.h"
+#include "debug.h"
+#include "namespaces.h"
+#include "comm.h"
+#include "map.h"
+#include "symbol.h"
+#include "unwind.h"
+#include "callchain.h"
+#include "dwarf-regs.h"
+
+#include <api/fs/fs.h>
+
+int thread__init_maps(struct thread *thread, struct machine *machine)
+{
+ pid_t pid = thread__pid(thread);
+
+ if (pid == thread__tid(thread) || pid == -1) {
+ thread__set_maps(thread, maps__new(machine));
+ } else {
+ struct thread *leader = machine__findnew_thread(machine, pid, pid);
+
+ if (leader) {
+ thread__set_maps(thread, maps__get(thread__maps(leader)));
+ thread__put(leader);
+ }
+ }
+
+ return thread__maps(thread) ? 0 : -1;
+}
+
+struct thread *thread__new(pid_t pid, pid_t tid)
+ NO_THREAD_SAFETY_ANALYSIS /* Allocation/creation is inherently single threaded. */
+{
+ RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread));
+ struct thread *thread;
+
+ if (ADD_RC_CHK(thread, _thread) != NULL) {
+ struct comm *comm;
+ char comm_str[32];
+
+ thread__set_pid(thread, pid);
+ thread__set_tid(thread, tid);
+ thread__set_ppid(thread, -1);
+ thread__set_cpu(thread, -1);
+ thread__set_guest_cpu(thread, -1);
+ thread__set_e_machine(thread, EM_NONE);
+ thread__set_e_is_big_endian(thread, false);
+ thread__set_lbr_stitch_enable(thread, false);
+ INIT_LIST_HEAD(thread__namespaces_list(thread));
+ INIT_LIST_HEAD(thread__comm_list(thread));
+ init_rwsem(thread__namespaces_lock(thread));
+ init_rwsem(thread__comm_lock(thread));
+
+ snprintf(comm_str, sizeof(comm_str), ":%d", tid);
+ comm = comm__new(comm_str, 0, false);
+ if (!comm)
+ goto err_thread;
+
+ list_add(&comm->list, thread__comm_list(thread));
+ refcount_set(thread__refcnt(thread), 1);
+ /* Thread holds first ref to nsdata. */
+ RC_CHK_ACCESS(thread)->nsinfo = nsinfo__new(pid);
+ srccode_state_init(thread__srccode_state(thread));
+ }
+
+ return thread;
+
+err_thread:
+ thread__delete(thread);
+ return NULL;
+}
+
+static void (*thread__priv_destructor)(void *priv);
+
+void thread__set_priv_destructor(void (*destructor)(void *priv))
+{
+ assert(thread__priv_destructor == NULL);
+
+ thread__priv_destructor = destructor;
+}
+
+void thread__delete(struct thread *thread)
+{
+ struct namespaces *namespaces, *tmp_namespaces;
+ struct comm *comm, *tmp_comm;
+
+ thread_stack__free(thread);
+
+ if (thread__maps(thread)) {
+ maps__put(thread__maps(thread));
+ thread__set_maps(thread, NULL);
+ }
+ down_write(thread__namespaces_lock(thread));
+ list_for_each_entry_safe(namespaces, tmp_namespaces,
+ thread__namespaces_list(thread), list) {
+ list_del_init(&namespaces->list);
+ namespaces__free(namespaces);
+ }
+ up_write(thread__namespaces_lock(thread));
+
+ down_write(thread__comm_lock(thread));
+ list_for_each_entry_safe(comm, tmp_comm, thread__comm_list(thread), list) {
+ list_del_init(&comm->list);
+ comm__free(comm);
+ }
+ up_write(thread__comm_lock(thread));
+
+ nsinfo__zput(RC_CHK_ACCESS(thread)->nsinfo);
+ srccode_state_free(thread__srccode_state(thread));
+
+ exit_rwsem(thread__namespaces_lock(thread));
+ exit_rwsem(thread__comm_lock(thread));
+ thread__free_stitch_list(thread);
+
+ if (thread__priv_destructor)
+ thread__priv_destructor(thread__priv(thread));
+
+ RC_CHK_FREE(thread);
+}
+
+struct thread *thread__get(struct thread *thread)
+{
+ struct thread *result;
+
+ if (RC_CHK_GET(result, thread))
+ refcount_inc(thread__refcnt(thread));
+
+ return result;
+}
+
+void thread__put(struct thread *thread)
+{
+ if (thread && refcount_dec_and_test(thread__refcnt(thread)))
+ thread__delete(thread);
+ else
+ RC_CHK_PUT(thread);
+}
+
+static struct namespaces *__thread__namespaces(struct thread *thread)
+{
+ if (list_empty(thread__namespaces_list(thread)))
+ return NULL;
+
+ return list_first_entry(thread__namespaces_list(thread), struct namespaces, list);
+}
+
+struct namespaces *thread__namespaces(struct thread *thread)
+{
+ struct namespaces *ns;
+
+ down_read(thread__namespaces_lock(thread));
+ ns = __thread__namespaces(thread);
+ up_read(thread__namespaces_lock(thread));
+
+ return ns;
+}
+
+static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
+ struct perf_record_namespaces *event)
+{
+ struct namespaces *new, *curr = __thread__namespaces(thread);
+
+ new = namespaces__new(event);
+ if (!new)
+ return -ENOMEM;
+
+ list_add(&new->list, thread__namespaces_list(thread));
+
+ if (timestamp && curr) {
+ /*
+ * setns syscall must have changed few or all the namespaces
+ * of this thread. Update end time for the namespaces
+ * previously used.
+ */
+ curr = list_next_entry(new, list);
+ curr->end_time = timestamp;
+ }
+
+ return 0;
+}
+
+int thread__set_namespaces(struct thread *thread, u64 timestamp,
+ struct perf_record_namespaces *event)
+{
+ int ret;
+
+ down_write(thread__namespaces_lock(thread));
+ ret = __thread__set_namespaces(thread, timestamp, event);
+ up_write(thread__namespaces_lock(thread));
+ return ret;
+}
+
+static struct comm *__thread__comm(struct thread *thread)
+ SHARED_LOCKS_REQUIRED(thread__comm_lock(thread))
+{
+ if (list_empty(thread__comm_list(thread)))
+ return NULL;
+
+ return list_first_entry(thread__comm_list(thread), struct comm, list);
+}
+
+struct comm *thread__comm(struct thread *thread)
+{
+ struct comm *res = NULL;
+
+ down_read(thread__comm_lock(thread));
+ res = __thread__comm(thread);
+ up_read(thread__comm_lock(thread));
+ return res;
+}
+
+struct comm *thread__exec_comm(struct thread *thread)
+{
+ struct comm *comm, *last = NULL, *second_last = NULL;
+
+ down_read(thread__comm_lock(thread));
+ list_for_each_entry(comm, thread__comm_list(thread), list) {
+ if (comm->exec) {
+ up_read(thread__comm_lock(thread));
+ return comm;
+ }
+ second_last = last;
+ last = comm;
+ }
+ up_read(thread__comm_lock(thread));
+
+ /*
+ * 'last' with no start time might be the parent's comm of a synthesized
+ * thread (created by processing a synthesized fork event). For a main
+ * thread, that is very probably wrong. Prefer a later comm to avoid
+ * that case.
+ */
+ if (second_last && !last->start && thread__pid(thread) == thread__tid(thread))
+ return second_last;
+
+ return last;
+}
+
+static int ____thread__set_comm(struct thread *thread, const char *str,
+ u64 timestamp, bool exec)
+ EXCLUSIVE_LOCKS_REQUIRED(thread__comm_lock(thread))
+{
+ struct comm *new, *curr = __thread__comm(thread);
+
+ /* Override the default :tid entry */
+ if (!thread__comm_set(thread)) {
+ int err = comm__override(curr, str, timestamp, exec);
+ if (err)
+ return err;
+ } else {
+ new = comm__new(str, timestamp, exec);
+ if (!new)
+ return -ENOMEM;
+ list_add(&new->list, thread__comm_list(thread));
+
+ if (exec)
+ unwind__flush_access(thread__maps(thread));
+ }
+
+ thread__set_comm_set(thread, true);
+
+ return 0;
+}
+
+int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
+ bool exec)
+{
+ int ret;
+
+ down_write(thread__comm_lock(thread));
+ ret = ____thread__set_comm(thread, str, timestamp, exec);
+ up_write(thread__comm_lock(thread));
+ return ret;
+}
+
+int thread__set_comm_from_proc(struct thread *thread)
+{
+ char path[64];
+ char *comm = NULL;
+ size_t sz;
+ int err = -1;
+
+ if (!(snprintf(path, sizeof(path), "%d/task/%d/comm",
+ thread__pid(thread), thread__tid(thread)) >= (int)sizeof(path)) &&
+ procfs__read_str(path, &comm, &sz) == 0) {
+ /* sz==0: read got nothing, e.g. race during exit teardown */
+ if (sz == 0) {
+ free(comm);
+ return -1;
+ }
+ comm[sz - 1] = '\0';
+ err = thread__set_comm(thread, comm, 0);
+ }
+
+ return err;
+}
+
+static const char *__thread__comm_str(struct thread *thread)
+ SHARED_LOCKS_REQUIRED(thread__comm_lock(thread))
+{
+ const struct comm *comm = __thread__comm(thread);
+
+ if (!comm)
+ return NULL;
+
+ return comm__str(comm);
+}
+
+const char *thread__comm_str(struct thread *thread)
+{
+ const char *str;
+
+ down_read(thread__comm_lock(thread));
+ str = __thread__comm_str(thread);
+ up_read(thread__comm_lock(thread));
+
+ return str;
+}
+
+static int __thread__comm_len(struct thread *thread, const char *comm)
+{
+ if (!comm)
+ return 0;
+ thread__set_comm_len(thread, strlen(comm));
+
+ return thread__var_comm_len(thread);
+}
+
+/* CHECKME: it should probably better return the max comm len from its comm list */
+int thread__comm_len(struct thread *thread)
+{
+ int comm_len = thread__var_comm_len(thread);
+
+ if (!comm_len) {
+ const char *comm;
+
+ down_read(thread__comm_lock(thread));
+ comm = __thread__comm_str(thread);
+ comm_len = __thread__comm_len(thread, comm);
+ up_read(thread__comm_lock(thread));
+ }
+
+ return comm_len;
+}
+
+size_t thread__fprintf(struct thread *thread, FILE *fp)
+{
+ return fprintf(fp, "Thread %d %s\n", thread__tid(thread), thread__comm_str(thread)) +
+ maps__fprintf(thread__maps(thread), fp);
+}
+
+int thread__insert_map(struct thread *thread, struct map *map)
+{
+ int ret;
+ uint16_t e_machine;
+
+ ret = maps__fixup_overlap_and_insert(thread__maps(thread), map);
+ if (ret)
+ return ret;
+
+ e_machine = thread__e_machine(thread, /*machine=*/NULL, /*e_flags=*/NULL);
+ return unwind__prepare_access(thread__maps(thread), e_machine);
+}
+
+static int thread__prepare_access(struct thread *thread)
+{
+ uint16_t e_machine = thread__e_machine(thread, /*machine=*/NULL, /*e_flags=*/NULL);
+
+ return unwind__prepare_access(thread__maps(thread), e_machine);
+}
+
+static int thread__clone_maps(struct thread *thread, struct thread *parent, bool do_maps_clone)
+{
+ /* This is new thread, we share map groups for process. */
+ if (thread__pid(thread) == thread__pid(parent))
+ return thread__prepare_access(thread);
+
+ if (maps__equal(thread__maps(thread), thread__maps(parent))) {
+ pr_debug("broken map groups on thread %d/%d parent %d/%d\n",
+ thread__pid(thread), thread__tid(thread),
+ thread__pid(parent), thread__tid(parent));
+ return 0;
+ }
+ /* But this one is new process, copy maps. */
+ return do_maps_clone ? maps__copy_from(thread__maps(thread), thread__maps(parent)) : 0;
+}
+
+int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone)
+{
+ if (thread__comm_set(parent)) {
+ const char *comm = thread__comm_str(parent);
+ int err;
+ if (!comm)
+ return -ENOMEM;
+ err = thread__set_comm(thread, comm, timestamp);
+ if (err)
+ return err;
+ }
+
+ thread__set_ppid(thread, thread__tid(parent));
+ return thread__clone_maps(thread, parent, do_maps_clone);
+}
+
+void thread__find_cpumode_addr_location(struct thread *thread, u64 addr,
+ bool symbols, struct addr_location *al)
+{
+ size_t i;
+ const u8 cpumodes[] = {
+ PERF_RECORD_MISC_USER,
+ PERF_RECORD_MISC_KERNEL,
+ PERF_RECORD_MISC_GUEST_USER,
+ PERF_RECORD_MISC_GUEST_KERNEL
+ };
+
+ for (i = 0; i < ARRAY_SIZE(cpumodes); i++) {
+ if (symbols)
+ thread__find_symbol(thread, cpumodes[i], addr, al);
+ else
+ thread__find_map(thread, cpumodes[i], addr, al);
+
+ if (al->map)
+ break;
+ }
+}
+
+static uint16_t read_proc_e_machine_for_pid(pid_t pid, uint32_t *e_flags, bool *is_big_endian)
+{
+ char path[6 /* "/proc/" */ + 11 /* max length of pid */ + 5 /* "/exe\0" */];
+ int fd;
+ uint16_t e_machine = EM_NONE;
+
+ snprintf(path, sizeof(path), "/proc/%d/exe", pid);
+ fd = open(path, O_RDONLY);
+ if (fd >= 0) {
+ e_machine = dso__read_e_machine_endian(/*optional_dso=*/NULL, fd, e_flags,
+ is_big_endian);
+ close(fd);
+ }
+ return e_machine;
+}
+
+struct thread__e_machine_callback_args {
+ struct machine *machine;
+ uint32_t e_flags;
+ uint16_t e_machine;
+ bool is_big_endian;
+};
+
+static int thread__e_machine_callback(struct map *map, void *_args)
+{
+ struct thread__e_machine_callback_args *args = _args;
+ struct dso *dso = map__dso(map);
+
+ if (!dso)
+ return 0; // No dso, continue search.
+
+ args->e_machine =
+ dso__e_machine_endian(dso, args->machine, &args->e_flags, &args->is_big_endian);
+ return args->e_machine != EM_NONE ? 1 /* stop search */ : 0 /* continue search */;
+}
+
+uint16_t thread__e_machine_endian(struct thread *thread, struct machine *machine, uint32_t *e_flags,
+ bool *is_big_endian)
+{
+ pid_t tid, pid;
+ uint16_t e_machine;
+ uint32_t local_e_flags = 0;
+ struct thread__e_machine_callback_args args;
+
+ if (!thread) {
+ if (is_big_endian) {
+ *is_big_endian = perf_arch_is_big_endian(
+ machine && machine->env ? perf_env__arch(machine->env) : NULL);
+ }
+ return perf_env__e_machine(machine ? machine->env : NULL, e_flags);
+ }
+
+ e_machine = RC_CHK_ACCESS(thread)->e_machine;
+ args.machine = machine;
+ args.e_flags = 0;
+ args.e_machine = EM_NONE;
+ args.is_big_endian = false;
+
+ if (e_machine != EM_NONE) {
+ if (e_flags)
+ *e_flags = thread__e_flags(thread);
+ if (is_big_endian)
+ *is_big_endian = thread__e_is_big_endian(thread);
+ return e_machine;
+ }
+
+ if (machine == NULL) {
+ struct maps *maps = thread__maps(thread);
+
+ machine = maps__machine(maps);
+ args.machine = machine;
+ }
+ tid = thread__tid(thread);
+ pid = thread__pid(thread);
+ if (pid != tid) {
+ struct thread *parent = machine__findnew_thread(machine, pid, pid);
+
+ if (parent) {
+ e_machine = thread__e_machine_endian(parent, machine, &local_e_flags,
+ &args.is_big_endian);
+ thread__put(parent);
+ goto out;
+ }
+ /* Something went wrong, fallback. */
+ }
+ /* Reading on the PID thread. First try to find from the maps. */
+ maps__for_each_map(thread__maps(thread), thread__e_machine_callback, &args);
+
+ if (args.e_machine != EM_NONE) {
+ e_machine = args.e_machine;
+ local_e_flags = args.e_flags;
+ } else {
+ /* Maps failed, perhaps we're live with map events disabled. */
+ bool is_live = machine->machines == NULL;
+
+ if (!is_live) {
+ /* Check if the session has a data file. */
+ struct perf_session *session = container_of(machine->machines,
+ struct perf_session,
+ machines);
+
+ is_live = !!session->data;
+ }
+ /* Read from /proc/pid/exe if live. */
+ if (is_live) {
+ e_machine = read_proc_e_machine_for_pid(pid, &local_e_flags,
+ &args.is_big_endian);
+ } else if (machine && machine->env) {
+ /* Offline analysis: fallback to environment metadata. */
+ e_machine = perf_env__e_machine(machine->env, &local_e_flags);
+ args.is_big_endian = perf_arch_is_big_endian(perf_env__arch(machine->env));
+ }
+ }
+out:
+ if (e_machine != EM_NONE) {
+ thread__set_e_flags(thread, local_e_flags);
+ thread__set_e_is_big_endian(thread, args.is_big_endian);
+ thread__set_e_machine(thread, e_machine);
+ if (is_big_endian)
+ *is_big_endian = args.is_big_endian;
+ } else {
+ e_machine = EM_HOST;
+ local_e_flags = EF_HOST;
+ if (is_big_endian)
+ *is_big_endian = (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__);
+ }
+ if (e_flags)
+ *e_flags = local_e_flags;
+ return e_machine;
+}
+
+struct thread *thread__main_thread(struct machine *machine, struct thread *thread)
+{
+ if (thread__pid(thread) == thread__tid(thread))
+ return thread__get(thread);
+
+ if (thread__pid(thread) == -1)
+ return NULL;
+
+ return machine__find_thread(machine, thread__pid(thread), thread__pid(thread));
+}
+
+int thread__memcpy(struct thread *thread, struct machine *machine,
+ void *buf, u64 ip, int len, bool *is64bit)
+{
+ u8 cpumode = PERF_RECORD_MISC_USER;
+ struct addr_location al;
+ struct dso *dso;
+ long offset;
+
+ if (machine__kernel_ip(machine, ip))
+ cpumode = PERF_RECORD_MISC_KERNEL;
+
+ addr_location__init(&al);
+ if (!thread__find_map(thread, cpumode, ip, &al)) {
+ addr_location__exit(&al);
+ return -1;
+ }
+
+ dso = map__dso(al.map);
+
+ if (!dso || dso__data(dso)->status == DSO_DATA_STATUS_ERROR || map__load(al.map) < 0) {
+ addr_location__exit(&al);
+ return -1;
+ }
+
+ offset = map__map_ip(al.map, ip);
+ if (is64bit)
+ *is64bit = dso__is_64_bit(dso);
+
+ addr_location__exit(&al);
+
+ return dso__data_read_offset(dso, machine, offset, buf, len);
+}
+
+void thread__free_stitch_list(struct thread *thread)
+{
+ struct lbr_stitch *lbr_stitch = thread__lbr_stitch(thread);
+ struct stitch_list *pos, *tmp;
+
+ if (!lbr_stitch)
+ return;
+
+ list_for_each_entry_safe(pos, tmp, &lbr_stitch->lists, node) {
+ map_symbol__exit(&pos->cursor.ms);
+ list_del_init(&pos->node);
+ free(pos);
+ }
+
+ list_for_each_entry_safe(pos, tmp, &lbr_stitch->free_lists, node) {
+ list_del_init(&pos->node);
+ free(pos);
+ }
+
+ for (unsigned int i = 0 ; i < lbr_stitch->prev_lbr_cursor_size; i++)
+ map_symbol__exit(&lbr_stitch->prev_lbr_cursor[i].ms);
+
+ zfree(&lbr_stitch->prev_lbr_cursor);
+ free(thread__lbr_stitch(thread));
+ thread__set_lbr_stitch(thread, NULL);
+}