diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2020-02-25 00:14:51 +0300 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-05-19 16:51:18 +0300 |
| commit | e616cb8daadf637175af4fe53138a94c190c4816 (patch) | |
| tree | 60c33e92ebdb9d023fe37e3be98d4978e145dfc4 /include/linux/lockdep.h | |
| parent | 69ea03b56ed2c7189ccd0b5910ad39f3cad1df21 (diff) | |
| download | linux-e616cb8daadf637175af4fe53138a94c190c4816.tar.xz | |
lockdep: Always inline lockdep_{off,on}()
These functions are called {early,late} in nmi_{enter,exit} and should
not be traced or probed. They are also puny, so 'inline' them.
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Link: https://lkml.kernel.org/r/20200505134101.048523500@linutronix.de
Diffstat (limited to 'include/linux/lockdep.h')
| -rw-r--r-- | include/linux/lockdep.h | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 206774ac6946..8fce5c98a4b0 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -308,8 +308,27 @@ extern void lockdep_set_selftest_task(struct task_struct *task); extern void lockdep_init_task(struct task_struct *task); -extern void lockdep_off(void); -extern void lockdep_on(void); +/* + * Split the recrursion counter in two to readily detect 'off' vs recursion. + */ +#define LOCKDEP_RECURSION_BITS 16 +#define LOCKDEP_OFF (1U << LOCKDEP_RECURSION_BITS) +#define LOCKDEP_RECURSION_MASK (LOCKDEP_OFF - 1) + +/* + * lockdep_{off,on}() are macros to avoid tracing and kprobes; not inlines due + * to header dependencies. + */ + +#define lockdep_off() \ +do { \ + current->lockdep_recursion += LOCKDEP_OFF; \ +} while (0) + +#define lockdep_on() \ +do { \ + current->lockdep_recursion -= LOCKDEP_OFF; \ +} while (0) extern void lockdep_register_key(struct lock_class_key *key); extern void lockdep_unregister_key(struct lock_class_key *key); |