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    SubjectRe: [PATCH] Avoid overflows in kernel/time.c
    On Thu, Nov 29, 2007 at 04:19:51PM -0800, H. Peter Anvin wrote:
    > When the conversion factor between jiffies and milli- or microseconds
    > is not a single multiply or divide, as for the case of HZ == 300, we
    > currently do a multiply followed by a divide. The intervening
    > result, however, is subject to overflows, especially since the
    > fraction is not simplified (for HZ == 300, we multiply by 300 and
    > divide by 1000).
    >...
    > kernel/Makefile | 8 +++
    > kernel/time.c | 29 +++++++++---
    > kernel/timeconst.bc | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++
    > 3 files changed, 152 insertions(+), 8 deletions(-)
    > create mode 100644 kernel/timeconst.bc
    >...

    I have read the hep text, but are the advantages of HZ == 300 really
    visible or was this more theoretical?

    In the latter case, we might remove the HZ == 300 choice instead.

    cu
    Adrian

    --

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    "Only a promise," Lao Er said.
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