[PATCH v1 07/20] perf thread: Add reference count checking

From: Ian Rogers
Date: Tue Jun 06 2023 - 21:45:27 EST

Modify struct declaration and accessor functions for the reference
count checkers additional layer of indirection. Make sure pid_cmp in
builtin-sched.c uses the underlying/original struct in pointer
arithmetic, and not the temporary get/put indirection.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/builtin-sched.c | 4 +-
tools/perf/tests/hists_link.c | 2 +-
tools/perf/ui/hist.c | 5 ++-
tools/perf/util/hist.c | 2 +-
tools/perf/util/machine.c | 2 +-
tools/perf/util/sort.c | 2 +-
tools/perf/util/thread.c | 20 +++++----
tools/perf/util/thread.h | 79 ++++++++++++++++++-----------------
8 files changed, 63 insertions(+), 53 deletions(-)

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index c75ad82a6729..cd79068200e5 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -1385,7 +1385,7 @@ static int pid_cmp(struct work_atoms *l, struct work_atoms *r)
{
pid_t l_tid, r_tid;

- if (l->thread == r->thread)
+ if (RC_CHK_ACCESS(l->thread) == RC_CHK_ACCESS(r->thread))
return 0;
l_tid = thread__tid(l->thread);
r_tid = thread__tid(r->thread);
@@ -1393,7 +1393,7 @@ static int pid_cmp(struct work_atoms *l, struct work_atoms *r)
return -1;
if (l_tid > r_tid)
return 1;
- return (int)(l->thread - r->thread);
+ return (int)(RC_CHK_ACCESS(l->thread) - RC_CHK_ACCESS(r->thread));
}

static int avg_cmp(struct work_atoms *l, struct work_atoms *r)
diff --git a/tools/perf/tests/hists_link.c b/tools/perf/tests/hists_link.c
index 12bad8840699..2d19657ab5e0 100644
--- a/tools/perf/tests/hists_link.c
+++ b/tools/perf/tests/hists_link.c
@@ -148,7 +148,7 @@ static int find_sample(struct sample *samples, size_t nr_samples,
struct thread *t, struct map *m, struct symbol *s)
{
while (nr_samples--) {
- if (samples->thread == t &&
+ if (RC_CHK_ACCESS(samples->thread) == RC_CHK_ACCESS(t) &&
RC_CHK_ACCESS(samples->map) == RC_CHK_ACCESS(m) &&
samples->sym == s)
return 1;
diff --git a/tools/perf/ui/hist.c b/tools/perf/ui/hist.c
index f164bd26fc41..2bf959d08354 100644
--- a/tools/perf/ui/hist.c
+++ b/tools/perf/ui/hist.c
@@ -11,6 +11,7 @@
#include "../util/sort.h"
#include "../util/evsel.h"
#include "../util/evlist.h"
+#include "../util/thread.h"
#include "../util/util.h"

/* hist period print (hpp) functions */
@@ -274,7 +275,9 @@ static int __hpp__sort_acc(struct hist_entry *a, struct hist_entry *b,
if (ret)
return ret;

- if (a->thread != b->thread || !hist_entry__has_callchains(a) || !symbol_conf.use_callchain)
+ if ((a->thread == NULL ? NULL : RC_CHK_ACCESS(a->thread)) !=
+ (b->thread == NULL ? NULL : RC_CHK_ACCESS(b->thread)) ||
+ !hist_entry__has_callchains(a) || !symbol_conf.use_callchain)
return 0;

ret = b->callchain->max_depth - a->callchain->max_depth;
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index a4c1b617f6e4..dfda52d348a3 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -2124,7 +2124,7 @@ static bool hists__filter_entry_by_thread(struct hists *hists,
struct hist_entry *he)
{
if (hists->thread_filter != NULL &&
- he->thread != hists->thread_filter) {
+ RC_CHK_ACCESS(he->thread) != RC_CHK_ACCESS(hists->thread_filter)) {
he->filtered |= (1 << HIST_FILTER__THREAD);
return true;
}
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index 9fcf357a4d53..261188766307 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -2055,7 +2055,7 @@ static void __machine__remove_thread(struct machine *machine, struct thread_rb_n
if (!nd)
nd = thread_rb_node__find(th, &threads->entries.rb_root);

- if (threads->last_match == th)
+ if (threads->last_match && RC_CHK_ACCESS(threads->last_match) == RC_CHK_ACCESS(th))
threads__set_last_match(threads, NULL);

if (lock)
diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 5e45c770f91d..047c3606802f 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -128,7 +128,7 @@ static int hist_entry__thread_filter(struct hist_entry *he, int type, const void
if (type != HIST_FILTER__THREAD)
return -1;

- return th && he->thread != th;
+ return th && RC_CHK_ACCESS(he->thread) != RC_CHK_ACCESS(th);
}

struct sort_entry sort_thread = {
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 9fa4dc09dd2a..eba36dc2cd1d 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -41,9 +41,10 @@ struct thread *thread__new(pid_t pid, pid_t tid)
{
char *comm_str;
struct comm *comm;
- struct thread *thread = zalloc(sizeof(*thread));
+ RC_STRUCT(thread) *_thread = zalloc(sizeof(*_thread));
+ struct thread *thread;

- if (thread != NULL) {
+ if (ADD_RC_CHK(thread, _thread) != NULL) {
thread__set_pid(thread, pid);
thread__set_tid(thread, tid);
thread__set_ppid(thread, -1);
@@ -68,7 +69,7 @@ struct thread *thread__new(pid_t pid, pid_t tid)
list_add(&comm->list, thread__comm_list(thread));
refcount_set(thread__refcnt(thread), 1);
/* Thread holds first ref to nsdata. */
- thread->nsinfo = nsinfo__new(pid);
+ RC_CHK_ACCESS(thread)->nsinfo = nsinfo__new(pid);
srccode_state_init(thread__srccode_state(thread));
}

@@ -105,26 +106,31 @@ void thread__delete(struct thread *thread)
}
up_write(thread__comm_lock(thread));

- nsinfo__zput(thread->nsinfo);
+ 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);
- free(thread);
+ RC_CHK_FREE(thread);
}

struct thread *thread__get(struct thread *thread)
{
- if (thread)
+ struct thread *result;
+
+ if (RC_CHK_GET(result, thread))
refcount_inc(thread__refcnt(thread));
- return 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)
diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h
index b103992c3831..9068a21ce0fa 100644
--- a/tools/perf/util/thread.h
+++ b/tools/perf/util/thread.h
@@ -15,6 +15,7 @@
#include "rwsem.h"
#include "event.h"
#include "callchain.h"
+#include <internal/rc_check.h>

struct addr_location;
struct map;
@@ -34,7 +35,7 @@ struct thread_rb_node {
struct thread *thread;
};

-struct thread {
+DECLARE_RC_STRUCT(thread) {
struct maps *maps;
pid_t pid_; /* Not all tools update this */
pid_t tid;
@@ -123,192 +124,192 @@ int thread__memcpy(struct thread *thread, struct machine *machine,

static inline struct maps *thread__maps(struct thread *thread)
{
- return thread->maps;
+ return RC_CHK_ACCESS(thread)->maps;
}

static inline void thread__set_maps(struct thread *thread, struct maps *maps)
{
- thread->maps = maps;
+ RC_CHK_ACCESS(thread)->maps = maps;
}

static inline pid_t thread__pid(const struct thread *thread)
{
- return thread->pid_;
+ return RC_CHK_ACCESS(thread)->pid_;
}

static inline void thread__set_pid(struct thread *thread, pid_t pid_)
{
- thread->pid_ = pid_;
+ RC_CHK_ACCESS(thread)->pid_ = pid_;
}

static inline pid_t thread__tid(const struct thread *thread)
{
- return thread->tid;
+ return RC_CHK_ACCESS(thread)->tid;
}

static inline void thread__set_tid(struct thread *thread, pid_t tid)
{
- thread->tid = tid;
+ RC_CHK_ACCESS(thread)->tid = tid;
}

static inline pid_t thread__ppid(const struct thread *thread)
{
- return thread->ppid;
+ return RC_CHK_ACCESS(thread)->ppid;
}

static inline void thread__set_ppid(struct thread *thread, pid_t ppid)
{
- thread->ppid = ppid;
+ RC_CHK_ACCESS(thread)->ppid = ppid;
}

static inline int thread__cpu(const struct thread *thread)
{
- return thread->cpu;
+ return RC_CHK_ACCESS(thread)->cpu;
}

static inline void thread__set_cpu(struct thread *thread, int cpu)
{
- thread->cpu = cpu;
+ RC_CHK_ACCESS(thread)->cpu = cpu;
}

static inline int thread__guest_cpu(const struct thread *thread)
{
- return thread->guest_cpu;
+ return RC_CHK_ACCESS(thread)->guest_cpu;
}

static inline void thread__set_guest_cpu(struct thread *thread, int guest_cpu)
{
- thread->guest_cpu = guest_cpu;
+ RC_CHK_ACCESS(thread)->guest_cpu = guest_cpu;
}

static inline refcount_t *thread__refcnt(struct thread *thread)
{
- return &thread->refcnt;
+ return &RC_CHK_ACCESS(thread)->refcnt;
}

static inline bool thread__comm_set(const struct thread *thread)
{
- return thread->comm_set;
+ return RC_CHK_ACCESS(thread)->comm_set;
}

static inline void thread__set_comm_set(struct thread *thread, bool set)
{
- thread->comm_set = set;
+ RC_CHK_ACCESS(thread)->comm_set = set;
}

static inline int thread__var_comm_len(const struct thread *thread)
{
- return thread->comm_len;
+ return RC_CHK_ACCESS(thread)->comm_len;
}

static inline void thread__set_comm_len(struct thread *thread, int len)
{
- thread->comm_len = len;
+ RC_CHK_ACCESS(thread)->comm_len = len;
}

static inline struct list_head *thread__namespaces_list(struct thread *thread)
{
- return &thread->namespaces_list;
+ return &RC_CHK_ACCESS(thread)->namespaces_list;
}

static inline int thread__namespaces_list_empty(const struct thread *thread)
{
- return list_empty(&thread->namespaces_list);
+ return list_empty(&RC_CHK_ACCESS(thread)->namespaces_list);
}

static inline struct rw_semaphore *thread__namespaces_lock(struct thread *thread)
{
- return &thread->namespaces_lock;
+ return &RC_CHK_ACCESS(thread)->namespaces_lock;
}

static inline struct list_head *thread__comm_list(struct thread *thread)
{
- return &thread->comm_list;
+ return &RC_CHK_ACCESS(thread)->comm_list;
}

static inline struct rw_semaphore *thread__comm_lock(struct thread *thread)
{
- return &thread->comm_lock;
+ return &RC_CHK_ACCESS(thread)->comm_lock;
}

static inline u64 thread__db_id(const struct thread *thread)
{
- return thread->db_id;
+ return RC_CHK_ACCESS(thread)->db_id;
}

static inline void thread__set_db_id(struct thread *thread, u64 db_id)
{
- thread->db_id = db_id;
+ RC_CHK_ACCESS(thread)->db_id = db_id;
}

static inline void *thread__priv(struct thread *thread)
{
- return thread->priv;
+ return RC_CHK_ACCESS(thread)->priv;
}

static inline void thread__set_priv(struct thread *thread, void *p)
{
- thread->priv = p;
+ RC_CHK_ACCESS(thread)->priv = p;
}

static inline struct thread_stack *thread__ts(struct thread *thread)
{
- return thread->ts;
+ return RC_CHK_ACCESS(thread)->ts;
}

static inline void thread__set_ts(struct thread *thread, struct thread_stack *ts)
{
- thread->ts = ts;
+ RC_CHK_ACCESS(thread)->ts = ts;
}

static inline struct nsinfo *thread__nsinfo(struct thread *thread)
{
- return thread->nsinfo;
+ return RC_CHK_ACCESS(thread)->nsinfo;
}

static inline struct srccode_state *thread__srccode_state(struct thread *thread)
{
- return &thread->srccode_state;
+ return &RC_CHK_ACCESS(thread)->srccode_state;
}

static inline bool thread__filter(const struct thread *thread)
{
- return thread->filter;
+ return RC_CHK_ACCESS(thread)->filter;
}

static inline void thread__set_filter(struct thread *thread, bool filter)
{
- thread->filter = filter;
+ RC_CHK_ACCESS(thread)->filter = filter;
}

static inline int thread__filter_entry_depth(const struct thread *thread)
{
- return thread->filter_entry_depth;
+ return RC_CHK_ACCESS(thread)->filter_entry_depth;
}

static inline void thread__set_filter_entry_depth(struct thread *thread, int depth)
{
- thread->filter_entry_depth = depth;
+ RC_CHK_ACCESS(thread)->filter_entry_depth = depth;
}

static inline bool thread__lbr_stitch_enable(const struct thread *thread)
{
- return thread->lbr_stitch_enable;
+ return RC_CHK_ACCESS(thread)->lbr_stitch_enable;
}

static inline void thread__set_lbr_stitch_enable(struct thread *thread, bool en)
{
- thread->lbr_stitch_enable = en;
+ RC_CHK_ACCESS(thread)->lbr_stitch_enable = en;
}

static inline struct lbr_stitch *thread__lbr_stitch(struct thread *thread)
{
- return thread->lbr_stitch;
+ return RC_CHK_ACCESS(thread)->lbr_stitch;
}

static inline void thread__set_lbr_stitch(struct thread *thread, struct lbr_stitch *lbrs)
{
- thread->lbr_stitch = lbrs;
+ RC_CHK_ACCESS(thread)->lbr_stitch = lbrs;
}

static inline bool thread__is_filtered(struct thread *thread)
--
2.41.0.rc0.172.g3f132b7071-goog