diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-10-20 00:02:47 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-10-20 00:02:47 +0400 |
| commit | dfc568e6bc08916f1035af456e4631c47166b5cf (patch) | |
| tree | 3c96bdc26687e0f6958e790c8c93c0c6efb6b8d6 /include/linux/timex.h | |
| parent | fdf91dae6f024c6dfee425fe754df6b1957f6c53 (diff) | |
| parent | 31d141e3a666269a3b6fcccddb0351caf7454240 (diff) | |
| download | linux-dfc568e6bc08916f1035af456e4631c47166b5cf.tar.xz | |
Merge 3.12-rc6 into char-misc-next
We want the fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/timex.h')
| -rw-r--r-- | include/linux/timex.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h index dd3edd7dfc94..9d3f1a5b6178 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -64,6 +64,20 @@ #include <asm/timex.h> +#ifndef random_get_entropy +/* + * The random_get_entropy() function is used by the /dev/random driver + * in order to extract entropy via the relative unpredictability of + * when an interrupt takes places versus a high speed, fine-grained + * timing source or cycle counter. Since it will be occurred on every + * single interrupt, it must have a very low cost/overhead. + * + * By default we use get_cycles() for this purpose, but individual + * architectures may override this in their asm/timex.h header file. + */ +#define random_get_entropy() get_cycles() +#endif + /* * SHIFT_PLL is used as a dampening factor to define how much we * adjust the frequency correction for a given offset in PLL mode. |