From 3f4b61a0b8de67ef9f20737919c713ddfc4bd620 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Mon, 6 Jul 2020 11:48:09 -0700 Subject: x86: Add thresholds for "rep movsb/stosb" to tunables Add x86_rep_movsb_threshold and x86_rep_stosb_threshold to tunables to update thresholds for "rep movsb" and "rep stosb" at run-time. Note that the user specified threshold for "rep movsb" smaller than the minimum threshold will be ignored. Reviewed-by: Carlos O'Donell --- manual/tunables.texi | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'manual') diff --git a/manual/tunables.texi b/manual/tunables.texi index ec18b10834..4e68c7ff91 100644 --- a/manual/tunables.texi +++ b/manual/tunables.texi @@ -396,6 +396,22 @@ to set threshold in bytes for non temporal store. This tunable is specific to i386 and x86-64. @end deftp +@deftp Tunable glibc.cpu.x86_rep_movsb_threshold +The @code{glibc.cpu.x86_rep_movsb_threshold} tunable allows the user to +set threshold in bytes to start using "rep movsb". The value must be +greater than zero, and currently defaults to 2048 bytes. + +This tunable is specific to i386 and x86-64. +@end deftp + +@deftp Tunable glibc.cpu.x86_rep_stosb_threshold +The @code{glibc.cpu.x86_rep_stosb_threshold} tunable allows the user to +set threshold in bytes to start using "rep stosb". The value must be +greater than zero, and currently defaults to 2048 bytes. + +This tunable is specific to i386 and x86-64. +@end deftp + @deftp Tunable glibc.cpu.x86_ibt The @code{glibc.cpu.x86_ibt} tunable allows the user to control how indirect branch tracking (IBT) should be enabled. Accepted values are -- cgit v1.2.3-70-g09d2