From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: X-Spam-Status: No, score=-4.0 required=3.0 tests=ALL_TRUSTED,BAYES_00 shortcircuit=no autolearn=ham autolearn_force=no version=3.4.1 Received: from localhost (dcvr.yhbt.net [127.0.0.1]) by dcvr.yhbt.net (Postfix) with ESMTP id 58E7B1F404; Sat, 11 Aug 2018 03:53:41 +0000 (UTC) From: Eric Wong To: mwrap-public@80x24.org Cc: Eric Wong Subject: [PATCH] struct acc: use 64-bit counters Date: Sat, 11 Aug 2018 03:53:39 +0000 Message-Id: <20180811035339.2044-1-e@80x24.org> List-Id: Since there's no hope of atomicity here anyways, use 64-bit counters. --- ext/mwrap/mwrap.c | 34 ++++++++++++++++++++-------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/ext/mwrap/mwrap.c b/ext/mwrap/mwrap.c index b60c21d..5174127 100644 --- a/ext/mwrap/mwrap.c +++ b/ext/mwrap/mwrap.c @@ -218,14 +218,14 @@ static int has_ec_p(void) } struct acc { - size_t nr; - size_t min; - size_t max; + uint64_t nr; + int64_t min; + int64_t max; double m2; double mean; }; -#define ACC_INIT(name) { .nr=0, .min=SIZE_MAX, .max=0, .m2=0, .mean=0 } +#define ACC_INIT(name) { .nr=0, .min=INT64_MAX, .max=-1, .m2=0, .mean=0 } /* for tracking 16K-aligned heap page bodies (protected by GVL) */ struct { @@ -314,29 +314,35 @@ static void acc_add(struct acc *acc, size_t val) { double delta = val - acc->mean; - size_t nr = ++acc->nr; + uint64_t nr = ++acc->nr; - /* 32-bit overflow, ignore accuracy, just don't divide-by-zero */ + /* just don't divide-by-zero if we ever hit this (unlikely :P) */ if (nr) acc->mean += delta / nr; acc->m2 += delta * (val - acc->mean); - if (val < acc->min) - acc->min = val; - if (val > acc->max) - acc->max = val; + if ((int64_t)val < acc->min) + acc->min = (int64_t)val; + if ((int64_t)val > acc->max) + acc->max = (int64_t)val; } +#if SIZEOF_LONG == 8 +# define INT64toNUM(x) LONG2NUM((long)x) +#elif defined(HAVE_LONG_LONG) && SIZEOF_LONG_LONG == 8 +# define INT64toNUM(x) LL2NUM((LONG_LONG)x) +#endif + static VALUE acc_max(const struct acc *acc) { - return acc->max ? SIZET2NUM(acc->max) : DBL2NUM(HUGE_VAL); + return INT64toNUM(acc->max); } static VALUE acc_min(const struct acc *acc) { - return acc->min == SIZE_MAX ? DBL2NUM(HUGE_VAL) : SIZET2NUM(acc->min); + return acc->min == INT64_MAX ? INT2FIX(-1) : INT64toNUM(acc->min); } static VALUE @@ -1360,12 +1366,12 @@ static void dump_hpb(FILE *fp, unsigned flags) "deathspan_stddev: %0.3f\n" "gc_count: %zu\n", hpb_stats.alive.max, - hpb_stats.alive.min == SIZE_MAX ? " -" : " ", + hpb_stats.alive.min == INT64_MAX ? " -" : " ", hpb_stats.alive.min, hpb_stats.alive.mean, acc_stddev_dbl(&hpb_stats.alive), hpb_stats.reborn.max, - hpb_stats.reborn.min == SIZE_MAX ? " -" : " ", + hpb_stats.reborn.min == INT64_MAX ? " -" : " ", hpb_stats.reborn.min, hpb_stats.reborn.mean, acc_stddev_dbl(&hpb_stats.reborn), -- EW