Messages in this thread | | | Date | Mon, 30 Nov 2009 10:28:13 +0000 | From | Ian Molton <> | Subject | Re: [PATCH 1/2] hw_random: core updates to allow more efficient drivers |
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Rusty Russell wrote:
> And might as well just #defube RNG_BUFFSIZE SMP_CACHE_BYTES (or use > SMP_CACHE_BYTES here and sizeof() elsewhere).
This can lead to a rather small (4 byte) buffer on some systems, however I don't know if in practice a tiny buffer or a big one would be better for performance on those machines. I guess if its a problem someone can patch the code to allocate a minimum of (say) 16 bytes in future...
so changed :)
>>> + if (!data_avail) { >>> + bytes_read = rng_get_data(current_rng, rng_buffer, >>> + RNG_BUFFSIZE, !(filp->f_flags & O_NONBLOCK)); >> No need to pass rng_buffer to the helper as there's only one with global >> scope. > > Naah, I like the separation; it matches the rest of the kernel and means we > can get funky with buffer management in 10 years time when we rewrite this > again.
Tweaked to use sizeof().
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