From 2ee7711bdd7de9dd30073b223ce29d5cd50320f6 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sun, 13 Dec 2020 04:56:41 -0800 Subject: [PATCH] x86: Remove the default REP MOVSB threshold tunable value [BZ #27061] Since we can't tell if the tunable value is set by user or not: https://sourceware.org/bugzilla/show_bug.cgi?id=27069 remove the default REP MOVSB threshold tunable value so that the correct default value will be set correctly by init_cacheinfo (). Reviewed-by: Carlos O'Donell --- sysdeps/x86/dl-tunables.list | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/sysdeps/x86/dl-tunables.list b/sysdeps/x86/dl-tunables.list index 1a4a93a070..bc26e9fa01 100644 --- a/sysdeps/x86/dl-tunables.list +++ b/sysdeps/x86/dl-tunables.list @@ -39,9 +39,11 @@ glibc { # REP MOVSB. Since larger register size can move more data with a # single load and store, the threshold is higher with larger register # size. Note: Since the REP MOVSB threshold must be greater than 8 - # times of vector size, the minium value must be updated at run-time. + # times of vector size and the default value is 2048 * (vector size + # / 16), the default value and the minimum value must be updated at + # run-time. NB: Don't set the default value since we can't tell if + # the tunable value is set by user or not [BZ #27069]. minval: 1 - default: 2048 } x86_rep_stosb_threshold { type: SIZE_T