sched/cpufreq: Fix 32-bit math overflow

Vincent Wang reported that get_next_freq() has a mult overflow bug on
32-bit platforms in the IOWAIT boost case, since in that case {util,max}
are in freq units instead of capacity units.

Solve this by moving the IOWAIT boost to capacity units. And since this
means @max is constant; simplify the code.

Reported-by: Vincent Wang <[email protected]>
Tested-by: Vincent Wang <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Chunyan Zhang <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Quentin Perret <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

0 files changed, 0 insertions, 0 deletions