| Message ID | 1435424869-17455-2-git-send-email-damien.lespiau@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, Jun 27, 2015 at 06:07:47PM +0100, Damien Lespiau wrote: > Chris mentioned he wanted to be able to measure a variable "for one > second" and use igt_stats to store them. That's one case where we don't > know the number of data points upfront. > > We should really support that, so here it is. > > Signed-off-by: Damien Lespiau <damien.lespiau@intel.com> > --- > lib/igt_stats.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 48 insertions(+), 4 deletions(-) > > diff --git a/lib/igt_stats.c b/lib/igt_stats.c > index caf3f37..cd97ab0 100644 > --- a/lib/igt_stats.c > +++ b/lib/igt_stats.c > @@ -63,6 +63,41 @@ > * ]| > */ > > +static unsigned int get_new_capacity(int need) > +{ > + unsigned int new_capacity; > + > + /* taken from Python's list */ > + new_capacity = (need >> 6) + (need < 9 ? 3 : 6); > + new_capacity += need; > + > + return new_capacity; > +} > + > +static void igt_stats_ensure_capacity(igt_stats_t *stats, > + unsigned int n_additional_values) > +{ > + unsigned int new_n_values = stats->n_values + n_additional_values; > + unsigned int new_capacity; > + > + if (new_n_values <= stats->capacity) > + return; > + > + new_capacity = get_new_capacity(new_n_values); > + stats->values = realloc(stats->values, > + sizeof(*stats->values) * new_capacity); > + igt_assert(stats->values); > + > + stats->capacity = new_capacity; > + > + if (!stats->sorted) > + return; > + > + stats->sorted = realloc(stats->sorted, > + sizeof(*stats->values) * new_capacity); > + igt_assert(stats->sorted); There isn't any point in preserving the sorted array when pushing new values. Might as well just free here and allocate again when required. -Chris
On Sat, Jun 27, 2015 at 06:15:42PM +0100, Chris Wilson wrote: > > +static void igt_stats_ensure_capacity(igt_stats_t *stats, > > + unsigned int n_additional_values) > > +{ > > + unsigned int new_n_values = stats->n_values + n_additional_values; > > + unsigned int new_capacity; > > + > > + if (new_n_values <= stats->capacity) > > + return; > > + > > + new_capacity = get_new_capacity(new_n_values); > > + stats->values = realloc(stats->values, > > + sizeof(*stats->values) * new_capacity); > > + igt_assert(stats->values); > > + > > + stats->capacity = new_capacity; > > + > > + if (!stats->sorted) > > + return; > > + > > + stats->sorted = realloc(stats->sorted, > > + sizeof(*stats->values) * new_capacity); > > + igt_assert(stats->sorted); > > There isn't any point in preserving the sorted array when pushing new > values. Might as well just free here and allocate again when required. Indeed, push the whole thing so far with this change.
diff --git a/lib/igt_stats.c b/lib/igt_stats.c index caf3f37..cd97ab0 100644 --- a/lib/igt_stats.c +++ b/lib/igt_stats.c @@ -63,6 +63,41 @@ * ]| */ +static unsigned int get_new_capacity(int need) +{ + unsigned int new_capacity; + + /* taken from Python's list */ + new_capacity = (need >> 6) + (need < 9 ? 3 : 6); + new_capacity += need; + + return new_capacity; +} + +static void igt_stats_ensure_capacity(igt_stats_t *stats, + unsigned int n_additional_values) +{ + unsigned int new_n_values = stats->n_values + n_additional_values; + unsigned int new_capacity; + + if (new_n_values <= stats->capacity) + return; + + new_capacity = get_new_capacity(new_n_values); + stats->values = realloc(stats->values, + sizeof(*stats->values) * new_capacity); + igt_assert(stats->values); + + stats->capacity = new_capacity; + + if (!stats->sorted) + return; + + stats->sorted = realloc(stats->sorted, + sizeof(*stats->values) * new_capacity); + igt_assert(stats->sorted); +} + /** * igt_stats_init: * @stats: An #igt_stats_t instance @@ -78,9 +113,7 @@ void igt_stats_init(igt_stats_t *stats, unsigned int capacity) { memset(stats, 0, sizeof(*stats)); - stats->values = calloc(capacity, sizeof(*stats->values)); - igt_assert(stats->values); - stats->capacity = capacity; + igt_stats_ensure_capacity(stats, capacity); stats->min = U64_MAX; stats->max = 0; @@ -156,7 +189,8 @@ void igt_stats_set_population(igt_stats_t *stats, bool full_population) */ void igt_stats_push(igt_stats_t *stats, uint64_t value) { - igt_assert(stats->n_values < stats->capacity); + igt_stats_ensure_capacity(stats, 1); + stats->values[stats->n_values++] = value; stats->mean_variance_valid = false; @@ -181,6 +215,8 @@ void igt_stats_push_array(igt_stats_t *stats, { unsigned int i; + igt_stats_ensure_capacity(stats, n_values); + for (i = 0; i < n_values; i++) igt_stats_push(stats, values[i]); } @@ -240,6 +276,14 @@ static void igt_stats_ensure_sorted_values(igt_stats_t *stats) return; if (!stats->sorted) { + /* + * We could always allocate sorted, but doing it lazily will + * consume a bit less memory if the user doesn't use any of the + * functions needing to sort the data points. + * + * igt_stats_ensure_capacity() will take care of reallocating + * sorted when needed after this initial allocation. + */ stats->sorted = calloc(stats->capacity, sizeof(*stats->values)); igt_assert(stats->sorted); }
Chris mentioned he wanted to be able to measure a variable "for one second" and use igt_stats to store them. That's one case where we don't know the number of data points upfront. We should really support that, so here it is. Signed-off-by: Damien Lespiau <damien.lespiau@intel.com> --- lib/igt_stats.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 48 insertions(+), 4 deletions(-)