perf kvm: Use subtraction for comparison metrics

Currently the metrics comparison uses greater operator (>), it returns
the boolean value (0 or 1).

This patch changes to use subtraction as comparison result, which can
be used by histograms sorting.  Since the subtraction result is u64
type, we change key_cmp_fun's return type to int64_t to avoid overflow.

Signed-off-by: Leo Yan <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: John Garry <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

0 files changed, 0 insertions, 0 deletions