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| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-04-27 20:06:03 +0300 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-06-25 21:26:24 +0300 |
| commit | fd55a281adf6c9b9723d369203fdd92e5ea62a09 (patch) | |
| tree | ca1bef1a9ab9480443368d6b82a8408a113db18d /include/linux/srcu.h | |
| parent | 5ab07a8df4d6c958ca63640d3f2ef896f0679c05 (diff) | |
| download | linux-fd55a281adf6c9b9723d369203fdd92e5ea62a09.tar.xz | |
srcu: Introduce srcu_read_{un,}lock_notrace()
Joel Fernandes is using SRCU to protect from-idle tracepoints, which
requires notrace variants of srcu_read_lock() and srcu_read_unlock()
in order to avoid problems with tracepoints in lockdep. This commit
therefore adds srcu_read_lock_notrace() and srcu_read_unlock_notrace().
[1] http://lkml.kernel.org/r/20180427042656.190746-1-joelaf@google.com
Reported-by: Joel Fernandes <joelaf@google.com>
Intermittently-reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'include/linux/srcu.h')
| -rw-r--r-- | include/linux/srcu.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 91494d7e8e41..3e72a291c401 100644 --- a/include/linux/srcu.h +++ b/include/linux/srcu.h @@ -195,6 +195,16 @@ static inline int srcu_read_lock(struct srcu_struct *sp) __acquires(sp) return retval; } +/* Used by tracing, cannot be traced and cannot invoke lockdep. */ +static inline notrace int +srcu_read_lock_notrace(struct srcu_struct *sp) __acquires(sp) +{ + int retval; + + retval = __srcu_read_lock(sp); + return retval; +} + /** * srcu_read_unlock - unregister a old reader from an SRCU-protected structure. * @sp: srcu_struct in which to unregister the old reader. @@ -209,6 +219,13 @@ static inline void srcu_read_unlock(struct srcu_struct *sp, int idx) __srcu_read_unlock(sp, idx); } +/* Used by tracing, cannot be traced and cannot call lockdep. */ +static inline notrace void +srcu_read_unlock_notrace(struct srcu_struct *sp, int idx) __releases(sp) +{ + __srcu_read_unlock(sp, idx); +} + /** * smp_mb__after_srcu_read_unlock - ensure full ordering after srcu_read_unlock * |