diff options
| author | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2022-07-07 15:29:34 +0100 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2023-10-30 12:56:10 +0000 |
| commit | 67656b683de3160ad9f3138a835ba82f21eecd5e (patch) | |
| tree | 8f262da7b726b246fa15ce7685117e7ec9c869ec | |
| parent | 7e8c94510668b74094dadd250537fd35a9360a4d (diff) | |
arm64: text replication: early kernel option to enable replication
Provide an early kernel option "ktext=" which allows the kernel text
replication to be enabled. This takes a boolean argument.
The way this has been implemented means that we take all the same paths
through the kernel at runtime whether kernel text replication has been
enabled or not; this allows the performance effects of the code changes
to be evaluated separately from the act of running with replicating the
kernel text.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 5 | ||||
| -rw-r--r-- | arch/arm64/mm/ktext.c | 18 |
2 files changed, 23 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 0a1731a0f0ef..d74fca365bed 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2526,6 +2526,11 @@ 0: force disabled 1: force enabled + ktext= [ARM64] Control kernel text replication on NUMA + machines. Default: disabled. + 0: disable kernel text replication + 1: enable kernel text replication + kunit.enable= [KUNIT] Enable executing KUnit tests. Requires CONFIG_KUNIT to be set to be fully enabled. The default value can be overridden via diff --git a/arch/arm64/mm/ktext.c b/arch/arm64/mm/ktext.c index 6ca7c4730893..f55bfe29ad28 100644 --- a/arch/arm64/mm/ktext.c +++ b/arch/arm64/mm/ktext.c @@ -119,6 +119,21 @@ void ktext_replication_patch_alternative(__le32 *src, int nr_inst) } } +static bool ktext_enabled; + +static int __init parse_ktext(char *str) +{ + bool enabled; + int ret = strtobool(str, &enabled); + + if (ret) + return ret; + + ktext_enabled = enabled; + return 0; +} +early_param("ktext", parse_ktext); + /* Allocate page tables and memory for the replicated kernel texts. */ void __init ktext_replication_init(void) { @@ -140,6 +155,9 @@ void __init ktext_replication_init(void) return; } + if (!ktext_enabled) + return; + for_each_node(nid) { /* Nothing to do for node 0 */ if (!nid) |