Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 2048d39..b64e9e0 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -1,18 +1,21 @@
// SPDX-License-Identifier: GPL-2.0
-#include "../perf.h"
#include <errno.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 "util.h"
#include "debug.h"
#include "namespaces.h"
#include "comm.h"
+#include "map.h"
+#include "symbol.h"
#include "unwind.h"
+#include "callchain.h"
#include <api/fs/fs.h>
@@ -64,6 +67,7 @@
RB_CLEAR_NODE(&thread->rb_node);
/* Thread holds first ref to nsdata. */
thread->nsinfo = nsinfo__new(pid);
+ srccode_state_init(&thread->srccode_state);
}
return thread;
@@ -89,20 +93,20 @@
down_write(&thread->namespaces_lock);
list_for_each_entry_safe(namespaces, tmp_namespaces,
&thread->namespaces_list, list) {
- list_del(&namespaces->list);
+ list_del_init(&namespaces->list);
namespaces__free(namespaces);
}
up_write(&thread->namespaces_lock);
down_write(&thread->comm_lock);
list_for_each_entry_safe(comm, tmp_comm, &thread->comm_list, list) {
- list_del(&comm->list);
+ list_del_init(&comm->list);
comm__free(comm);
}
up_write(&thread->comm_lock);
- unwind__finish_access(thread);
nsinfo__zput(thread->nsinfo);
+ srccode_state_free(&thread->srccode_state);
exit_rwsem(&thread->namespaces_lock);
exit_rwsem(&thread->comm_lock);
@@ -120,15 +124,32 @@
{
if (thread && refcount_dec_and_test(&thread->refcnt)) {
/*
- * Remove it from the dead_threads list, as last reference
- * is gone.
+ * Remove it from the dead threads list, as last reference is
+ * gone, if it is in a dead threads list.
+ *
+ * We may not be there anymore if say, the machine where it was
+ * stored was already deleted, so we already removed it from
+ * the dead threads and some other piece of code still keeps a
+ * reference.
+ *
+ * This is what 'perf sched' does and finally drops it in
+ * perf_sched__lat(), where it calls perf_sched__read_events(),
+ * that processes the events by creating a session and deleting
+ * it, which ends up destroying the list heads for the dead
+ * threads, but before it does that it removes all threads from
+ * it using list_del_init().
+ *
+ * So we need to check here if it is in a dead threads list and
+ * if so, remove it before finally deleting the thread, to avoid
+ * an use after free situation.
*/
- list_del_init(&thread->node);
+ if (!list_empty(&thread->node))
+ list_del_init(&thread->node);
thread__delete(thread);
}
}
-struct namespaces *thread__namespaces(const struct thread *thread)
+static struct namespaces *__thread__namespaces(const struct thread *thread)
{
if (list_empty(&thread->namespaces_list))
return NULL;
@@ -136,10 +157,21 @@
return list_first_entry(&thread->namespaces_list, struct namespaces, list);
}
-static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
- struct namespaces_event *event)
+struct namespaces *thread__namespaces(struct thread *thread)
{
- struct namespaces *new, *curr = thread__namespaces(thread);
+ struct namespaces *ns;
+
+ down_read(&thread->namespaces_lock);
+ ns = __thread__namespaces(thread);
+ up_read(&thread->namespaces_lock);
+
+ 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)
@@ -161,7 +193,7 @@
}
int thread__set_namespaces(struct thread *thread, u64 timestamp,
- struct namespaces_event *event)
+ struct perf_record_namespaces *event)
{
int ret;
@@ -181,14 +213,24 @@
struct comm *thread__exec_comm(const struct thread *thread)
{
- struct comm *comm, *last = NULL;
+ struct comm *comm, *last = NULL, *second_last = NULL;
list_for_each_entry(comm, &thread->comm_list, list) {
if (comm->exec)
return comm;
+ second_last = last;
last = comm;
}
+ /*
+ * '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->tid)
+ return second_last;
+
return last;
}
@@ -209,7 +251,7 @@
list_add(&new->list, &thread->comm_list);
if (exec)
- unwind__flush_access(thread);
+ unwind__flush_access(thread->mg);
}
thread->comm_set = true;
@@ -255,13 +297,13 @@
return comm__str(comm);
}
-const char *thread__comm_str(const struct thread *thread)
+const char *thread__comm_str(struct thread *thread)
{
const char *str;
- down_read((struct rw_semaphore *)&thread->comm_lock);
+ down_read(&thread->comm_lock);
str = __thread__comm_str(thread);
- up_read((struct rw_semaphore *)&thread->comm_lock);
+ up_read(&thread->comm_lock);
return str;
}
@@ -289,7 +331,7 @@
{
int ret;
- ret = unwind__prepare_access(thread, map, NULL);
+ ret = unwind__prepare_access(thread->mg, map, NULL);
if (ret)
return ret;
@@ -309,7 +351,7 @@
down_read(&maps->lock);
for (map = maps__first(maps); map; map = map__next(map)) {
- err = unwind__prepare_access(thread, map, &initialized);
+ err = unwind__prepare_access(thread->mg, map, &initialized);
if (err || initialized)
break;
}
@@ -323,14 +365,15 @@
{
int err = 0;
- if (symbol_conf.use_callchain)
+ if (dwarf_callchain_users)
err = __thread__prepare_access(thread);
return err;
}
static int thread__clone_map_groups(struct thread *thread,
- struct thread *parent)
+ struct thread *parent,
+ bool do_maps_clone)
{
/* This is new thread, we share map groups for process. */
if (thread->pid_ == parent->pid_)
@@ -341,15 +384,11 @@
thread->pid_, thread->tid, parent->pid_, parent->tid);
return 0;
}
-
/* But this one is new process, copy maps. */
- if (map_groups__clone(thread, parent->mg) < 0)
- return -ENOMEM;
-
- return 0;
+ return do_maps_clone ? map_groups__clone(thread, parent->mg) : 0;
}
-int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp)
+int thread__fork(struct thread *thread, struct thread *parent, u64 timestamp, bool do_maps_clone)
{
if (parent->comm_set) {
const char *comm = thread__comm_str(parent);
@@ -362,7 +401,7 @@
}
thread->ppid = parent->tid;
- return thread__clone_map_groups(thread, parent);
+ return thread__clone_map_groups(thread, parent, do_maps_clone);
}
void thread__find_cpumode_addr_location(struct thread *thread, u64 addr,
@@ -393,3 +432,25 @@
return machine__find_thread(machine, thread->pid_, thread->pid_);
}
+
+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;
+ long offset;
+
+ if (machine__kernel_ip(machine, ip))
+ cpumode = PERF_RECORD_MISC_KERNEL;
+
+ if (!thread__find_map(thread, cpumode, ip, &al) || !al.map->dso ||
+ al.map->dso->data.status == DSO_DATA_STATUS_ERROR ||
+ map__load(al.map) < 0)
+ return -1;
+
+ offset = al.map->map_ip(al.map, ip);
+ if (is64bit)
+ *is64bit = al.map->dso->is_64_bit;
+
+ return dso__data_read_offset(al.map->dso, machine, offset, buf, len);
+}