Synchronization mechanisms based on counters

A machine-readable storage medium having instructions, when executed by a machine, cause the machine to perform a method, the method comprising:

• maintaining a plurality of counters in memory including a lock counter and an unlock counter to synchronize a plurality of requests, the lock counter indicating a cumulative number of the requests, and the unlock counter indicating a cumulative number of a portion of the requests having released the lock;
• selecting at least one of the requests to grant a lock according to the counters;
• and
• performing the synchronized operations for the selected requests.

An apparatus, comprising:

• a synchronization library configured in a user mode to maintain a plurality of counters in memory including a lock counter and an unlock counter to synchronize a plurality of requests, the lock counter indicating a cumulative number of the requests, and the unlock counter indicating a cumulative number of a portion of the requests having released the lock;
• a kernel library configured in a kernel mode to select at least one of the requests to grant a lock according to the counters;
• and
• an interface module configured to performing the synchronized operations for the selected requests.

A computer implemented method, comprising:

• maintaining one or more counters to synchronize a plurality of requests for a lock, the counters having a state indicating values of the counters;
• calling a first kernel interface with a first state to wait for the lock;
• updating the counters atomically based on a second state of the counters returned from the first kernel interface;
• and
• performing synchronized operations subsequent to the update of the counters.

A machine-readable storage medium having instructions, when executed by a machine, cause the machine to perform a method, the method comprising:

• maintaining one or more counters in memory to synchronize a plurality of requests for a lock, the counters having a state indicating values of the counters;
• calling a first kernel interface with a first state to wait for the lock;
• updating the counters atomically based on a second state of the counters returned from the first kernel interface;
• and
• performing synchronized operations subsequent to the update of the counters.

An apparatus, comprising:

• a user library configured to maintain one or more counters in memory to synchronize a plurality of requests for a lock, the counters having a state indicating values of the counters, comprising:
• a lock handler module configured to count the lock counter for calling a first kernel interface with a first state to wait for the lock, and
• an unlock handler module configured to update the counters atomically based on a second state of the counters returned from the first kernel interface;
• and
• an interface module configured to perform synchronized operations subsequent to the update of the counters.

A computer implemented method, comprising:

• maintaining one or more counters in memory to synchronize a plurality of lock requests, each lock request being associated with a lock count indicating a cumulative number of the lock requests initiated for a lock when the lock request is received in a wait queue;
• in response to receiving an unlock request to release the lock, comparing a state of the counters with the unlock request to determine whether to expect additional lock requests;
• selecting one or more of the lock requests from the wait queue to grant the lock if no additional lock requests is expected;
• and
• performing synchronized operations for the selected lock requests.

A machine-readable storage medium having instructions, when executed by a machine, cause the machine to perform a method, the method comprising:

• maintaining one or more counters in memory to synchronize a plurality of lock requests, each lock request being associated with a lock count indicating a cumulative number of the lock requests initiated for a lock when the lock request is received in a wait queue;
• in response to receiving an unlock request to release the lock, comparing a state of the counters with the unlock request to determine whether to expect additional lock requests;
• selecting one or more of the lock requests from the wait queue to grant the lock if no additional lock requests is expected;
• and
• performing synchronized operations for the selected lock requests.

An apparatus, comprising:

• a wait queue to store one or more lock requests, each lock request being
• associated with a lock count indicating a cumulative number of the lock requests initiated for a lock;
• a kernel library configured to
• maintain one or more counters in memory to synchronize the lock requests,
• in response to receiving an unlock request to release the lock, compare a state of the counters with the unlock request to determine whether to expect additional lock requests, and
• select one or more of the lock requests from the wait queue to grant the lock if no additional lock requests is expected;
• and
• an interface module configured to perform synchronized operations subsequent to the update of the counters.

A computer implemented method, comprising:

• counting up a lock counter in memory atomically to wait for a lock to synchronize operations among a plurality of tasks;
• when the lock is granted, performing the synchronized operations for at least one of the plurality of tasks;
• and
• counting up an unlock counter in the memory atomically subsequent to the synchronized operations.