seqcount: Provide raw_read_seqcount() (0ea5a520) · Commits · 戴 / test

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 a NMI safe clock monotonic accessor function. Signed-off-by:

Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by:

John Stultz <john.stultz@linaro.org>

include/linux/seqlock.h

+16 −0

Original line number	Original line	Diff line number	Diff line
	@@ -116,6 +116,22 @@ repeat:
	return ret;		return ret;
	}		}

			/**
			* 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		* raw_read_seqcount_begin - start seq-read critical section w/o lockdep
	* @s: pointer to seqcount_t		* @s: pointer to seqcount_t

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