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A seqlock is a special locking mechanism used in Linux for supporting fast writes of shared variables between two parallel operating system routines.

It is a reader-writer consistent mechanism which avoids the problem of writer starvation. A seqlock consists of storage for saving a sequence number in addition to a lock. The lock is to support synchronization between two writers and the counter is for indicating consistency in readers.

Sequence locks use spinlocks to synchronize writers. When reading it waits for the spinlock counter to be even - writer finished writing.

Just instantiate a Seqlock object and use the methods BeginRead, EndRead, BeginWrite, EndWrite. Be aware that this lock doesn't support recurrent locking, so calling for example BeginWrite twice on the same thread without unlocking will cause a deadlock