When user sends multiple CSs, waiting for each CS is not efficient
as it involves many user-kernel context switches.
In order to address this issue we add support to "wait on multiple CSs"
using a new uAPI which can wait on maximum of 32 CSs. The new uAPI is
defined using a new flag - WAIT_FOR_MULTI_CS - in the wait_for_cs IOCTL.
The input parameters for this uAPI will be:
@seq: user pointer to an array of up to 32 CS's sequence numbers.
@seq_array_len: length of sequence array.
@timeout_us: timeout for waiting for any CS.
The output paramateres for this API will be:
@status: multi CS ioctl completion status (dedicated status was added as
well).
@flags: bitmap of output flags of the CS.
@cs_completion_map: bitmap for multi CS, if CS sequence that was placed
in index N in input seq array has completed- the N-th
bit in cs_completion_map will be 1, otherwise it will
be 0.
@timestamp_nsec: timestamp of the first completed CS
Signed-off-by: Ohad Sharabi <osharabi@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
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