| Message ID | 20190725160207.19579-6-osalvador@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Allocate memmap from hotadded memory | expand |
On 25.07.19 18:02, Oscar Salvador wrote: > It seems that we have some users out there that want to expose all > hotpluggable memory to userspace, so this implements a toggling mechanism > for those users who want to disable it. > > By default, vmemmap pages mechanism is enabled. > > Signed-off-by: Oscar Salvador <osalvador@suse.de> > --- > drivers/base/memory.c | 33 +++++++++++++++++++++++++++++++++ > include/linux/memory_hotplug.h | 3 +++ > mm/memory_hotplug.c | 7 +++++++ > 3 files changed, 43 insertions(+) > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index d30d0f6c8ad0..5ec6b80de9dd 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -578,6 +578,35 @@ static DEVICE_ATTR_WO(soft_offline_page); > static DEVICE_ATTR_WO(hard_offline_page); > #endif > -ENODOCUMENTATION :) > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > +static ssize_t vmemmap_hotplug_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + if (vmemmap_enabled) > + return sprintf(buf, "enabled\n"); > + else > + return sprintf(buf, "disabled\n"); > +} > + > +static ssize_t vmemmap_hotplug_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + if (!capable(CAP_SYS_ADMIN)) > + return -EPERM; > + > + if (sysfs_streq(buf, "enable")) > + vmemmap_enabled = true; > + else if (sysfs_streq(buf, "disable")) > + vmemmap_enabled = false; > + else > + return -EINVAL; > + > + return count; > +} > +static DEVICE_ATTR_RW(vmemmap_hotplug); > +#endif > + > /* > * Note that phys_device is optional. It is here to allow for > * differentiation between which *physical* devices each > @@ -794,6 +823,10 @@ static struct attribute *memory_root_attrs[] = { > &dev_attr_hard_offline_page.attr, > #endif > > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > + &dev_attr_vmemmap_hotplug.attr, Don't like the name of that property, sorry. > +#endif > + > &dev_attr_block_size_bytes.attr, > &dev_attr_auto_online_blocks.attr, > NULL > diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h > index e1e8abf22a80..03d227d13301 100644 > --- a/include/linux/memory_hotplug.h > +++ b/include/linux/memory_hotplug.h > @@ -134,6 +134,9 @@ extern int arch_add_memory(int nid, u64 start, u64 size, > struct mhp_restrictions *restrictions); > extern u64 max_mem_size; > > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > +extern bool vmemmap_enabled; > +#endif > extern bool memhp_auto_online; > /* If movable_node boot option specified */ > extern bool movable_node_enabled; > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 09d41339cd11..5ffe5375b87c 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -68,6 +68,10 @@ void put_online_mems(void) > > bool movable_node_enabled = false; > > +#ifdef CONFIG_SPARSEMEM_VMEMMAP > +bool vmemmap_enabled __read_mostly = true; > +#endif > + > #ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE > bool memhp_auto_online; > #else > @@ -1108,6 +1112,9 @@ static unsigned long mhp_check_flags(unsigned long flags) > if (!flags) > return 0; > > + if (!vmemmap_enabled) > + return 0; > + > if (flags != MHP_MEMMAP_ON_MEMORY) { > WARN(1, "Wrong flags value (%lx). Ignoring flags.\n", flags); > return 0; > Hmmm, I wonder if that should that rather be a per-memory device driver thingy? E.g., a toggle for ACPI which will then not pass in MHP_MEMMAP_ON_MEMORY.
diff --git a/drivers/base/memory.c b/drivers/base/memory.c index d30d0f6c8ad0..5ec6b80de9dd 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -578,6 +578,35 @@ static DEVICE_ATTR_WO(soft_offline_page); static DEVICE_ATTR_WO(hard_offline_page); #endif +#ifdef CONFIG_SPARSEMEM_VMEMMAP +static ssize_t vmemmap_hotplug_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (vmemmap_enabled) + return sprintf(buf, "enabled\n"); + else + return sprintf(buf, "disabled\n"); +} + +static ssize_t vmemmap_hotplug_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (sysfs_streq(buf, "enable")) + vmemmap_enabled = true; + else if (sysfs_streq(buf, "disable")) + vmemmap_enabled = false; + else + return -EINVAL; + + return count; +} +static DEVICE_ATTR_RW(vmemmap_hotplug); +#endif + /* * Note that phys_device is optional. It is here to allow for * differentiation between which *physical* devices each @@ -794,6 +823,10 @@ static struct attribute *memory_root_attrs[] = { &dev_attr_hard_offline_page.attr, #endif +#ifdef CONFIG_SPARSEMEM_VMEMMAP + &dev_attr_vmemmap_hotplug.attr, +#endif + &dev_attr_block_size_bytes.attr, &dev_attr_auto_online_blocks.attr, NULL diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index e1e8abf22a80..03d227d13301 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -134,6 +134,9 @@ extern int arch_add_memory(int nid, u64 start, u64 size, struct mhp_restrictions *restrictions); extern u64 max_mem_size; +#ifdef CONFIG_SPARSEMEM_VMEMMAP +extern bool vmemmap_enabled; +#endif extern bool memhp_auto_online; /* If movable_node boot option specified */ extern bool movable_node_enabled; diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 09d41339cd11..5ffe5375b87c 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -68,6 +68,10 @@ void put_online_mems(void) bool movable_node_enabled = false; +#ifdef CONFIG_SPARSEMEM_VMEMMAP +bool vmemmap_enabled __read_mostly = true; +#endif + #ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE bool memhp_auto_online; #else @@ -1108,6 +1112,9 @@ static unsigned long mhp_check_flags(unsigned long flags) if (!flags) return 0; + if (!vmemmap_enabled) + return 0; + if (flags != MHP_MEMMAP_ON_MEMORY) { WARN(1, "Wrong flags value (%lx). Ignoring flags.\n", flags); return 0;
It seems that we have some users out there that want to expose all hotpluggable memory to userspace, so this implements a toggling mechanism for those users who want to disable it. By default, vmemmap pages mechanism is enabled. Signed-off-by: Oscar Salvador <osalvador@suse.de> --- drivers/base/memory.c | 33 +++++++++++++++++++++++++++++++++ include/linux/memory_hotplug.h | 3 +++ mm/memory_hotplug.c | 7 +++++++ 3 files changed, 43 insertions(+)