Introduce HUGE_VMALLOC_DEFAULT_ENABLED and make it default y, this let user to choose whether or not enable huge vmalloc mappings by default. Meanwhile, add new hugevmalloc=on/off parameter to enable or disable this feature at boot time, nohugevmalloc is still supported and equivalent to hugevmalloc=off. Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> --- .../admin-guide/kernel-parameters.txt | 12 ++++++++++++ mm/Kconfig | 8 ++++++++ mm/vmalloc.c | 18 +++++++++++++++++- 3 files changed, 37 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index a069d8fe2fee..7b2f900fd243 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1638,6 +1638,18 @@ If both parameters are enabled, hugetlb_free_vmemmap takes precedence over memory_hotplug.memmap_on_memory. + + hugevmalloc= [PPC] Reguires CONFIG_HAVE_ARCH_HUGE_VMALLOC + Format: { on | off } + Default set by CONFIG_HUGE_VMALLOC_DEFAULT_ENABLED. + + This parameter enables/disables kernel huge vmalloc + mappings at boot time. + + on: Enable the feature + off: Disable the feature + Equivalent to: nohugevmalloc + hung_task_panic= [KNL] Should the hung task detector generate panics. Format: 0 | 1 diff --git a/mm/Kconfig b/mm/Kconfig index a99bd499ef51..8d8a92f22905 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -262,6 +262,14 @@ config HUGETLB_PAGE_SIZE_VARIABLE HUGETLB_PAGE_ORDER when there are multiple HugeTLB page sizes available on a platform. +config HUGE_VMALLOC_DEFAULT_ENABLED + bool "Enable huge vmalloc mappings by default" + default y + depends on HAVE_ARCH_HUGE_VMALLOC + help + Enable huge vmalloc mappings by default, this value could be overridden + by hugevmalloc=off|on. + config CONTIG_ALLOC def_bool (MEMORY_ISOLATION && COMPACTION) || CMA diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 9bf838817a47..0d0f8deb5639 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -60,7 +60,7 @@ static const unsigned int ioremap_max_page_shift = PAGE_SHIFT; #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ #ifdef CONFIG_HAVE_ARCH_HUGE_VMALLOC -static bool __ro_after_init vmap_allow_huge = true; +static bool __ro_after_init vmap_allow_huge = IS_ENABLED(CONFIG_HUGE_VMALLOC_DEFAULT_ENABLED); static int __init set_nohugevmalloc(char *str) { @@ -68,6 +68,22 @@ static int __init set_nohugevmalloc(char *str) return 0; } early_param("nohugevmalloc", set_nohugevmalloc); + +static int __init set_hugevmalloc(char *str) +{ + if (!str) + return -EINVAL; + + if (!strcmp(str, "on")) + vmap_allow_huge = true; + else if (!strcmp(str, "off")) + vmap_allow_huge = false; + else + return -EINVAL; + + return 0; +} +early_param("hugevmalloc", set_hugevmalloc); #else /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */ static const bool vmap_allow_huge = false; #endif /* CONFIG_HAVE_ARCH_HUGE_VMALLOC */ -- 2.26.2