Notime #130
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Notime #130
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Need a compile flag to ensure that we can use the new notime_imply infrastructure. So during configure check for the new registration symbol and add a HAVE_JITTER_NOTIME flag if we find it Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
jitter now offers support for software timing on platforms with a timer to coarse to support valid measurements. This new code registers our timer thread to take advantage of this feature Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
When using the software timer, we don't need to define our own init/fini functions, we can just use the common ones from the jitter lib that are provided as convienience. Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Add option to jitter to force use of soft timer Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Need to document our new soft timer option Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
When using soft timers, we need to limit our thread use to reduce contention between the jitter threads and the timer threads Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
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On some smaller systems the hardware clock is insufficiently fine grained to allow the jitterentropy source to accruately measure load and store times. In these cases jitter provides a software based thread to act as timer. However, it does not offer much control over said thread, and as a result we wind up with threads contending, and subsequent hangs or extra long latency on use. Fix this in rng-tools by activing the soft timer when needed and adjusting thread counts correspondingly