From 52c48c51e60c473ccedb4c8f428050041ca7076a Mon Sep 17 00:00:00 2001 From: Sascha Silbe Date: Tue, 5 Apr 2016 12:53:38 +0200 Subject: [PATCH] Documentation: document the nosmt and smt s390 kernel parameters Commit 6c2ff84e979a ("s390: add SMT support") added the nosmt and smt early kernel parameters for restricting the use of symmetric multithreading (SMT). They are quite useful for debugging and testing, so document them. Signed-off-by: Sascha Silbe Signed-off-by: Martin Schwidefsky --- Documentation/kernel-parameters.txt | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index ecc74fa..92435e7 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2538,6 +2538,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nohugeiomap [KNL,x86] Disable kernel huge I/O mappings. + nosmt [KNL,S390] Disable symmetric multithreading (SMT). + Equivalent to smt=1. + noxsave [BUGS=X86] Disables x86 extended register state save and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. @@ -3695,6 +3698,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. 1: Fast pin select (default) 2: ATC IRMode + smt [KNL,S390] Set the maximum number of threads (logical + CPUs) to use per physical CPU on systems capable of + symmetric multithreading (SMT). Will be capped to the + actual hardware limit. + Format: + Default: -1 (no limit) + softlockup_panic= [KNL] Should the soft-lockup detector generate panics. Format: -- 2.7.4