Gentle ping.
пт, 4 мая 2018 г. в 03:15, Timofey Titovets <nefelim4ag@xxxxxxxxx>:
>
> Skip testing unnecessary algorithms to speedup module initialization
>
> For my systems:
> Before: 1.510s (initrd)
> After: 977ms (initrd) # I set prefer to fastest algorithm
>
> Dmesg after patch:
> [ 1.190042] raid6: avx2x4 gen() 28153 MB/s
> [ 1.246683] raid6: avx2x4 xor() 19440 MB/s
> [ 1.246684] raid6: using algorithm avx2x4 gen() 28153 MB/s
> [ 1.246684] raid6: .... xor() 19440 MB/s, rmw enabled
> [ 1.246685] raid6: using avx2x2 recovery algorithm
>
> Signed-off-by: Timofey Titovets <nefelim4ag@xxxxxxxxx>
> CC: linux-btrfs@xxxxxxxxxxxxxxx
> ---
> lib/raid6/algos.c | 28 +++++++++++++++++++++++++---
> 1 file changed, 25 insertions(+), 3 deletions(-)
>
> diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c
> index 5065b1e7e327..abfcb4107fc3 100644
> --- a/lib/raid6/algos.c
> +++ b/lib/raid6/algos.c
> @@ -30,6 +30,11 @@ EXPORT_SYMBOL(raid6_empty_zero_page);
> #endif
> #endif
>
> +static char *prefer_name;
> +
> +module_param(prefer_name, charp, 0);
> +MODULE_PARM_DESC(prefer_name, "Prefer gen/xor() algorithm");
> +
> struct raid6_calls raid6_call;
> EXPORT_SYMBOL_GPL(raid6_call);
>
> @@ -155,10 +160,27 @@ static inline const struct raid6_calls *raid6_choose_gen(
> {
> unsigned long perf, bestgenperf, bestxorperf, j0, j1;
> int start = (disks>>1)-1, stop = disks-3; /* work on the second half of the disks */
> - const struct raid6_calls *const *algo;
> - const struct raid6_calls *best;
> + const struct raid6_calls *const *algo = NULL;
> + const struct raid6_calls *best = NULL;
> +
> + if (strlen(prefer_name)) {
> + for (algo = raid6_algos; strlen(prefer_name) && *algo; algo++) {
> + if (!strncmp(prefer_name, (*algo)->name, 8)) {
> + best = *algo;
> + break;
> + }
> + }
> + if (!best)
> + pr_info("raid6: %-8s prefer not found\n", prefer_name);
> + }
> +
> +
> +
> + if (!algo) {
> + algo = raid6_algos;
> + }
>
> - for (bestgenperf = 0, bestxorperf = 0, best = NULL, algo = raid6_algos; *algo; algo++) {
> + for (bestgenperf = 0, bestxorperf = 0; *algo; algo++) {
> if (!best || (*algo)->prefer >= best->prefer) {
> if ((*algo)->valid && !(*algo)->valid())
> continue;
> --
> 2.17.0
--
Have a nice day,
Timofey.
