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Altera_Forum
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12 years ago

Strange error message during kernel execution: "No kernel updates in a while..."

Hi all, I'm observing a strange error message during kernel execution on nallatech-pcie385n-d5 "No kernel updates in a while... a kernel may be hung" It comes with a list of kernels (ker...
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Altera_Forum
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12 years ago

FOR loops can also have subtle races.

LOOP Indices starting from a Linear Function of ThreadID (like for (int i=get_local_id(0);)) and ending against a comparison to constant N (constant for all threads) will also make the FOR loop unsuitable for BARRIERs.

e.g.

for(int i=get_local_id(0); i<N ; i+=get_local_size(0))

{

....

....

barrier(CLK_LOCAL_MEM_FENCE); // --> This is a bug.

}