raw_read_seqcount opens a read critical section of the given seqcount without any lockdep checking and without checking or masking the LSB. Calling code is responsible for handling that.
Preparatory patch to provide NMI safe clock monotonic[_raw] accessor functions. Signed-off-by: Thomas Gleixner <[email protected]> Cc: John Stultz <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ingo Molnar <[email protected]> --- include/linux/seqlock.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) Index: tip/include/linux/seqlock.h =================================================================== --- tip.orig/include/linux/seqlock.h +++ tip/include/linux/seqlock.h @@ -117,6 +117,22 @@ repeat: } /** + * raw_read_seqcount - Read the raw seqcount + * @s: pointer to seqcount_t + * Returns: count to be passed to read_seqcount_retry + * + * raw_read_seqcount opens a read critical section of the given + * seqcount without any lockdep checking and without checking or + * masking the LSB. Calling code is responsible for handling that. + */ +static inline unsigned raw_read_seqcount(const seqcount_t *s) +{ + unsigned ret = ACCESS_ONCE(s->sequence); + smp_rmb(); + return ret; +} + +/** * raw_read_seqcount_begin - start seq-read critical section w/o lockdep * @s: pointer to seqcount_t * Returns: count to be passed to read_seqcount_retry -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
