On Fri, 2021-10-29 at 16:53 +0200, Greg Kroah-Hartman wrote: > On Fri, Oct 29, 2021 at 03:18:57PM +0300, Jarkko Sakkinen wrote: > > The amount of SGX memory on the system is determined by the BIOS and it > > varies wildly between systems. It can be from dozens of MB's on desktops > > or VM's, up to many GB's on servers. Just like for regular memory, it is > > sometimes useful to know the amount of usable SGX memory in the system. > > > > Add an attribute for the amount of SGX memory in bytes to each NUMA > > node. The path is /sys/devices/system/node/node[0-9]*/sgx/size. > > Calculate these values by summing up EPC section sizes for each node > > during the driver initalization. > > > > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> > > --- > > v9: > > * Fix racy initialization of sysfs attributes: > > https://lore.kernel.org/linux-sgx/YXOsx8SvFJV5R7lU@xxxxxxxxx/ > > > > v8: > > * Fix a bug in sgx_numa_init(): node->dev should be only set after > > sysfe_create_group(). Otherwise, sysfs_remove_group() will issue a > > warning in sgx_numa_exit(), when sgx_create_group() is unsuccessful, > > because the group does not exist. > > > > v7: > > * Shorten memory_size to size. The prefix makes the name only longer > > but does not clarify things more than "size" would. > > * Use device_attribute instead of kobj_attribute. > > * Use named attribute group instead of creating raw kobject just for > > the "sgx" subdirectory. > > > > v6: > > * Initialize node->size to zero in sgx_setup_epc_section(), when the > > node is first accessed. > > > > v5 > > * A new patch based on the discussion on > > https://lore.kernel.org/linux-sgx/3a7cab4115b4f902f3509ad8652e616b91703e1d.camel@xxxxxxxxxx/T/#t > > --- > > Documentation/ABI/stable/sysfs-devices-node | 7 +++++ > > arch/x86/include/asm/sgx.h | 2 ++ > > arch/x86/kernel/cpu/sgx/main.c | 31 +++++++++++++++++++++ > > arch/x86/kernel/cpu/sgx/sgx.h | 2 ++ > > drivers/base/node.c | 16 ++++++++++- > > 5 files changed, 57 insertions(+), 1 deletion(-) > > > > diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node > > index 484fc04bcc25..12dc2149e8e0 100644 > > --- a/Documentation/ABI/stable/sysfs-devices-node > > +++ b/Documentation/ABI/stable/sysfs-devices-node > > @@ -176,3 +176,10 @@ Contact: Keith Busch <keith.busch@xxxxxxxxx> > > Description: > > The cache write policy: 0 for write-back, 1 for write-through, > > other or unknown. > > + > > +What: /sys/devices/system/node/nodeX/sgx/size > > +Date: October 2021 > > +Contact: Jarkko Sakkinen <jarkko@xxxxxxxxxx> > > +Description: > > + Total available physical SGX memory, also known as Enclave Page > > + Cache (EPC), in bytes. > > diff --git a/arch/x86/include/asm/sgx.h b/arch/x86/include/asm/sgx.h > > index 05f3e21f01a7..43d1ccae6c62 100644 > > --- a/arch/x86/include/asm/sgx.h > > +++ b/arch/x86/include/asm/sgx.h > > @@ -365,6 +365,8 @@ struct sgx_sigstruct { > > * comment! > > */ > > > > +extern const struct attribute_group sgx_node_group; > > + > > #ifdef CONFIG_X86_SGX_KVM > > int sgx_virt_ecreate(struct sgx_pageinfo *pageinfo, void __user *secs, > > int *trapnr); > > diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c > > index a6e313f1a82d..86d6d309ff29 100644 > > --- a/arch/x86/kernel/cpu/sgx/main.c > > +++ b/arch/x86/kernel/cpu/sgx/main.c > > @@ -714,9 +714,12 @@ static bool __init sgx_page_cache_init(void) > > spin_lock_init(&sgx_numa_nodes[nid].lock); > > INIT_LIST_HEAD(&sgx_numa_nodes[nid].free_page_list); > > node_set(nid, sgx_numa_mask); > > + sgx_numa_nodes[nid].size = 0; > > } > > > > sgx_epc_sections[i].node = &sgx_numa_nodes[nid]; > > + sgx_numa_nodes[nid].dev = &node_devices[nid]->dev; > > + sgx_numa_nodes[nid].size += size; > > > > sgx_nr_epc_sections++; > > } > > @@ -790,6 +793,34 @@ int sgx_set_attribute(unsigned long *allowed_attributes, > > } > > EXPORT_SYMBOL_GPL(sgx_set_attribute); > > > > +#ifdef CONFIG_NUMA > > +static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) > > +{ > > + unsigned long size = 0; > > + int nid; > > + > > + for (nid = 0; nid < num_possible_nodes(); nid++) { > > + if (dev == sgx_numa_nodes[nid].dev) { > > + size = sgx_numa_nodes[nid].size; > > + break; > > + } > > + } > > + > > + return sysfs_emit(buf, "%lu\n", size); > > +} > > +DEVICE_ATTR_RO(size); > > static? The named ("sgx") attribute group is exported: extern const struct attribute_group sgx_node_group; and added as an additional group of the node device: static const struct attribute_group node_dev_group = { .attrs = node_dev_attrs, }; static const struct attribute_group *node_dev_groups[] = { &node_dev_group, #ifdef CONFIG_X86_SGX &sgx_node_group, #endif /* CONFIG_X86_SGX */ NULL, }; An alternative would to define a helper, e.g. ssize_t sgx_get_node_size(struct device *dev); And use this in drivers/base/node.c to implement the attribute. I'm fine either way... /Jarkko
