diff options
Diffstat (limited to 'include/linux/mean_and_variance.h')
| -rw-r--r-- | include/linux/mean_and_variance.h | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/include/linux/mean_and_variance.h b/include/linux/mean_and_variance.h new file mode 100644 index 000000000000..280a16dea789 --- /dev/null +++ b/include/linux/mean_and_variance.h @@ -0,0 +1,37 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifndef STATS_H_ +#define STATS_H_ + +#include <linux/types.h> + +#define SQRT_U64_MAX 4294967295ULL + +struct mean_and_variance { + s64 n; + s64 sum; + u64 sum_squares; +}; + +/* expontentially weighted variant */ +struct mean_and_variance_ewm { + bool init; + u8 w; + s64 mean; + u64 variance; +}; + +#ifdef CONFIG_MEAN_AND_VARIANCE_UNIT_TEST +s64 fast_divpow2(s64 n, u8 d); +#endif + +struct mean_and_variance mean_and_variance_update(struct mean_and_variance s1, s64 v1); + s64 get_mean(struct mean_and_variance s); + u64 get_variance(struct mean_and_variance s1); + u32 get_stddev(struct mean_and_variance s); + +struct mean_and_variance_ewm mean_and_variance_ewm_update(struct mean_and_variance_ewm s1, s64 v1); + s64 get_ewm_mean(struct mean_and_variance_ewm s); + u64 get_ewm_variance(struct mean_and_variance_ewm s); + u32 get_ewm_stddev(struct mean_and_variance_ewm s); + +#endif // STATS_H_ |