diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-12-06 22:31:49 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-12-06 22:31:49 +0300 |
| commit | 92fc1f16e22f97dd5897c9200e620ebc287e50ef (patch) | |
| tree | f6333e4c0e0c603805e98853bd727b5e1bea5279 | |
| parent | 5e5ea7f61610239fca058011e7d4f342b34d1558 (diff) | |
| parent | 90dfeef1cd38dff19f8b3a752d13bfd79f0f7694 (diff) | |
| download | linux-92fc1f16e22f97dd5897c9200e620ebc287e50ef.tar.xz | |
Merge tag 'locking-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
"Two fixes related to recent introduction of scoped_seqlock_read():
- Fix compiler build failures when a particular .config and compiler
build options variant doesn't result in the expected removal of
unused, catch-bugs portions of scoped_seqlock_read() by the inliner
at build time, and cause a linker fail even in correct code
- Match read-locking order in do_task_stat() and do_io_accounting().
The inconsistency here was harmless but unnecessary"
* tag 'locking-urgent-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
seqlock: Cure some more scoped_seqlock() optimization fails
seqlock, procfs: Match scoped_seqlock_read() critical section vs. RCU ordering in do_task_stat() to do_io_accounting()
| -rw-r--r-- | fs/proc/array.c | 40 | ||||
| -rw-r--r-- | include/linux/seqlock.h | 4 |
2 files changed, 22 insertions, 22 deletions
diff --git a/fs/proc/array.c b/fs/proc/array.c index cbd4bc4a58e4..42932f88141a 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -537,27 +537,27 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns, if (permitted && (!whole || num_threads < 2)) wchan = !task_is_running(task); - scoped_seqlock_read (&sig->stats_lock, ss_lock_irqsave) { - cmin_flt = sig->cmin_flt; - cmaj_flt = sig->cmaj_flt; - cutime = sig->cutime; - cstime = sig->cstime; - cgtime = sig->cgtime; - - if (whole) { - struct task_struct *t; - - min_flt = sig->min_flt; - maj_flt = sig->maj_flt; - gtime = sig->gtime; - - rcu_read_lock(); - __for_each_thread(sig, t) { - min_flt += t->min_flt; - maj_flt += t->maj_flt; - gtime += task_gtime(t); + scoped_guard(rcu) { + scoped_seqlock_read (&sig->stats_lock, ss_lock_irqsave) { + cmin_flt = sig->cmin_flt; + cmaj_flt = sig->cmaj_flt; + cutime = sig->cutime; + cstime = sig->cstime; + cgtime = sig->cgtime; + + if (whole) { + struct task_struct *t; + + min_flt = sig->min_flt; + maj_flt = sig->maj_flt; + gtime = sig->gtime; + + __for_each_thread(sig, t) { + min_flt += t->min_flt; + maj_flt += t->maj_flt; + gtime += task_gtime(t); + } } - rcu_read_unlock(); } } diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h index a8a8661839b6..221123660e71 100644 --- a/include/linux/seqlock.h +++ b/include/linux/seqlock.h @@ -1224,7 +1224,7 @@ struct ss_tmp { spinlock_t *lock_irqsave; }; -static inline void __scoped_seqlock_cleanup(struct ss_tmp *sst) +static __always_inline void __scoped_seqlock_cleanup(struct ss_tmp *sst) { if (sst->lock) spin_unlock(sst->lock); @@ -1252,7 +1252,7 @@ static inline void __scoped_seqlock_bug(void) { } extern void __scoped_seqlock_bug(void); #endif -static inline void +static __always_inline void __scoped_seqlock_next(struct ss_tmp *sst, seqlock_t *lock, enum ss_state target) { switch (sst->state) { |
