* Re: [PATCH v1 1/5] drivers/base/memory: rename MMOP_ONLINE_KEEP to MMOP_ONLINE
From: Wei Yang @ 2020-03-11 14:17 UTC (permalink / raw)
To: David Hildenbrand
Cc: linux-hyperv, Baoquan He, Rafael J. Wysocki, Greg Kroah-Hartman,
linux-kernel, Michal Hocko, linux-mm, Andrew Morton, Wei Yang,
linuxppc-dev, Oscar Salvador
In-Reply-To: <20200311123026.16071-2-david@redhat.com>
On Wed, Mar 11, 2020 at 01:30:22PM +0100, David Hildenbrand wrote:
>The name is misleading. Let's just name it like the online_type name we
>expose to user space ("online").
>
>Add some documentation to the types.
>
>Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>Cc: Andrew Morton <akpm@linux-foundation.org>
>Cc: Michal Hocko <mhocko@kernel.org>
>Cc: Oscar Salvador <osalvador@suse.de>
>Cc: "Rafael J. Wysocki" <rafael@kernel.org>
>Cc: Baoquan He <bhe@redhat.com>
>Cc: Wei Yang <richard.weiyang@gmail.com>
>Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
>---
> drivers/base/memory.c | 9 +++++----
> include/linux/memory_hotplug.h | 6 +++++-
> 2 files changed, 10 insertions(+), 5 deletions(-)
>
>diff --git a/drivers/base/memory.c b/drivers/base/memory.c
>index 6448c9ece2cb..8c5ce42c0fc3 100644
>--- a/drivers/base/memory.c
>+++ b/drivers/base/memory.c
>@@ -216,7 +216,7 @@ static int memory_subsys_online(struct device *dev)
> * attribute and need to set the online_type.
> */
> if (mem->online_type < 0)
>- mem->online_type = MMOP_ONLINE_KEEP;
>+ mem->online_type = MMOP_ONLINE;
>
> ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
>
>@@ -251,7 +251,7 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
> else if (sysfs_streq(buf, "online_movable"))
> online_type = MMOP_ONLINE_MOVABLE;
> else if (sysfs_streq(buf, "online"))
>- online_type = MMOP_ONLINE_KEEP;
>+ online_type = MMOP_ONLINE;
> else if (sysfs_streq(buf, "offline"))
> online_type = MMOP_OFFLINE;
> else {
>@@ -262,7 +262,7 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
> switch (online_type) {
> case MMOP_ONLINE_KERNEL:
> case MMOP_ONLINE_MOVABLE:
>- case MMOP_ONLINE_KEEP:
>+ case MMOP_ONLINE:
> /* mem->online_type is protected by device_hotplug_lock */
> mem->online_type = online_type;
> ret = device_online(&mem->dev);
>@@ -342,7 +342,8 @@ static ssize_t valid_zones_show(struct device *dev,
> }
>
> nid = mem->nid;
>- default_zone = zone_for_pfn_range(MMOP_ONLINE_KEEP, nid, start_pfn, nr_pages);
>+ default_zone = zone_for_pfn_range(MMOP_ONLINE, nid, start_pfn,
>+ nr_pages);
> strcat(buf, default_zone->name);
>
> print_allowed_zone(buf, nid, start_pfn, nr_pages, MMOP_ONLINE_KERNEL,
>diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
>index f4d59155f3d4..261dbf010d5d 100644
>--- a/include/linux/memory_hotplug.h
>+++ b/include/linux/memory_hotplug.h
>@@ -47,9 +47,13 @@ enum {
>
> /* Types for control the zone type of onlined and offlined memory */
> enum {
>+ /* Offline the memory. */
> MMOP_OFFLINE = -1,
>- MMOP_ONLINE_KEEP,
>+ /* Online the memory. Zone depends, see default_zone_for_pfn(). */
>+ MMOP_ONLINE,
>+ /* Online the memory to ZONE_NORMAL. */
> MMOP_ONLINE_KERNEL,
>+ /* Online the memory to ZONE_MOVABLE. */
> MMOP_ONLINE_MOVABLE,
> };
>
>--
>2.24.1
--
Wei Yang
Help you, Help me
^ permalink raw reply
* [PATCH] ocxl: control via sysfs whether the FPGA is reloaded on a link reset
From: Philippe Bergheaud @ 2020-03-11 11:52 UTC (permalink / raw)
To: linuxppc-dev; +Cc: fbarrat, clombard, Philippe Bergheaud, ajd, alastair
Some opencapi FPGA images allow to control if the FPGA should be reloaded
on the next adapter reset. If it is supported, the image specifies it
through a Vendor Specific DVSEC in the config space of function 0.
This patch adds an interface to sysfs to control that behavior, if possible.
Signed-off-by: Philippe Bergheaud <felix@linux.ibm.com>
---
Documentation/ABI/testing/sysfs-class-ocxl | 10 ++++
drivers/misc/ocxl/config.c | 59 +++++++++++++++++++++-
drivers/misc/ocxl/ocxl_internal.h | 6 +++
drivers/misc/ocxl/sysfs.c | 35 +++++++++++++
include/misc/ocxl-config.h | 1 +
5 files changed, 110 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-class-ocxl b/Documentation/ABI/testing/sysfs-class-ocxl
index b5b1fa197592..b9ea671d5805 100644
--- a/Documentation/ABI/testing/sysfs-class-ocxl
+++ b/Documentation/ABI/testing/sysfs-class-ocxl
@@ -33,3 +33,13 @@ Date: January 2018
Contact: linuxppc-dev@lists.ozlabs.org
Description: read/write
Give access the global mmio area for the AFU
+
+What: /sys/class/ocxl/<afu name>/reload_on_reset
+Date: February 2020
+Contact: linuxppc-dev@lists.ozlabs.org
+Description: read/write
+ Control whether the FPGA is reloaded on a link reset
+ 0 Do not reload FPGA image from flash
+ 1 Reload FPGA image from flash
+ unavailable
+ The device does not support this capability
diff --git a/drivers/misc/ocxl/config.c b/drivers/misc/ocxl/config.c
index c8e19bfb5ef9..3488463c1640 100644
--- a/drivers/misc/ocxl/config.c
+++ b/drivers/misc/ocxl/config.c
@@ -71,6 +71,20 @@ static int find_dvsec_afu_ctrl(struct pci_dev *dev, u8 afu_idx)
return 0;
}
+/**
+ * get_function_0() - Find a related PCI device (function 0)
+ * @device: PCI device to match
+ *
+ * Returns a pointer to the related device, or null if not found
+ */
+static struct pci_dev *get_function_0(struct pci_dev *dev)
+{
+ unsigned int devfn = PCI_DEVFN(PCI_SLOT(dev->devfn), 0);
+
+ return pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus),
+ dev->bus->number, devfn);
+}
+
static void read_pasid(struct pci_dev *dev, struct ocxl_fn_config *fn)
{
u16 val;
@@ -159,7 +173,7 @@ static int read_dvsec_afu_info(struct pci_dev *dev, struct ocxl_fn_config *fn)
static int read_dvsec_vendor(struct pci_dev *dev)
{
int pos;
- u32 cfg, tlx, dlx;
+ u32 cfg, tlx, dlx, reset_reload;
/*
* vendor specific DVSEC is optional
@@ -178,11 +192,54 @@ static int read_dvsec_vendor(struct pci_dev *dev)
pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_CFG_VERS, &cfg);
pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_TLX_VERS, &tlx);
pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_DLX_VERS, &dlx);
+ pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_RESET_RELOAD, &reset_reload);
dev_dbg(&dev->dev, "Vendor specific DVSEC:\n");
dev_dbg(&dev->dev, " CFG version = 0x%x\n", cfg);
dev_dbg(&dev->dev, " TLX version = 0x%x\n", tlx);
dev_dbg(&dev->dev, " DLX version = 0x%x\n", dlx);
+ dev_dbg(&dev->dev, " ResetReload = 0x%x\n", reset_reload);
+ return 0;
+}
+
+int ocxl_config_get_reset_reload(struct pci_dev *dev, int *val)
+{
+ int reset_reload = -1;
+ int pos = 0;
+ struct pci_dev *dev0 = get_function_0(dev);
+
+ if (dev0)
+ pos = find_dvsec(dev0, OCXL_DVSEC_VENDOR_ID);
+
+ if (pos)
+ pci_read_config_dword(dev0,
+ pos + OCXL_DVSEC_VENDOR_RESET_RELOAD,
+ &reset_reload);
+ if (reset_reload == -1)
+ return reset_reload;
+
+ *val = reset_reload & BIT(0);
+ return 0;
+}
+
+int ocxl_config_set_reset_reload(struct pci_dev *dev, int val)
+{
+ int reset_reload = -1;
+ int pos = 0;
+ struct pci_dev *dev0 = get_function_0(dev);
+
+ if (dev0)
+ pos = find_dvsec(dev0, OCXL_DVSEC_VENDOR_ID);
+
+ if (pos)
+ pci_read_config_dword(dev0,
+ pos + OCXL_DVSEC_VENDOR_RESET_RELOAD,
+ &reset_reload);
+ if (reset_reload == -1)
+ return reset_reload;
+
+ val &= BIT(0);
+ pci_write_config_dword(dev0, pos + OCXL_DVSEC_VENDOR_RESET_RELOAD, val);
return 0;
}
diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h
index 345bf843a38e..af9a84aeee6f 100644
--- a/drivers/misc/ocxl/ocxl_internal.h
+++ b/drivers/misc/ocxl/ocxl_internal.h
@@ -112,6 +112,12 @@ void ocxl_actag_afu_free(struct ocxl_fn *fn, u32 start, u32 size);
*/
int ocxl_config_get_pasid_info(struct pci_dev *dev, int *count);
+/*
+ * Control whether the FPGA is reloaded on a link reset
+ */
+int ocxl_config_get_reset_reload(struct pci_dev *dev, int *val);
+int ocxl_config_set_reset_reload(struct pci_dev *dev, int val);
+
/*
* Check if an AFU index is valid for the given function.
*
diff --git a/drivers/misc/ocxl/sysfs.c b/drivers/misc/ocxl/sysfs.c
index 58f1ba264206..8f69f7311343 100644
--- a/drivers/misc/ocxl/sysfs.c
+++ b/drivers/misc/ocxl/sysfs.c
@@ -51,11 +51,46 @@ static ssize_t contexts_show(struct device *device,
afu->pasid_count, afu->pasid_max);
}
+static ssize_t reload_on_reset_show(struct device *device,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct ocxl_afu *afu = to_afu(device);
+ struct ocxl_fn *fn = afu->fn;
+ struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
+ int val;
+
+ if (ocxl_config_get_reset_reload(pci_dev, &val))
+ return scnprintf(buf, PAGE_SIZE, "unavailable\n");
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+}
+
+static ssize_t reload_on_reset_store(struct device *device,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ocxl_afu *afu = to_afu(device);
+ struct ocxl_fn *fn = afu->fn;
+ struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
+ int rc, val;
+
+ rc = sscanf(buf, "%i", &val);
+ if ((rc != 1) || !(val == 1 || val == 0))
+ return -EINVAL;
+
+ if (ocxl_config_set_reset_reload(pci_dev, val))
+ return -ENODEV;
+
+ return count;
+}
+
static struct device_attribute afu_attrs[] = {
__ATTR_RO(global_mmio_size),
__ATTR_RO(pp_mmio_size),
__ATTR_RO(afu_version),
__ATTR_RO(contexts),
+ __ATTR_RW(reload_on_reset),
};
static ssize_t global_mmio_read(struct file *filp, struct kobject *kobj,
diff --git a/include/misc/ocxl-config.h b/include/misc/ocxl-config.h
index 3526fa996a22..ccfd3b463517 100644
--- a/include/misc/ocxl-config.h
+++ b/include/misc/ocxl-config.h
@@ -41,5 +41,6 @@
#define OCXL_DVSEC_VENDOR_CFG_VERS 0x0C
#define OCXL_DVSEC_VENDOR_TLX_VERS 0x10
#define OCXL_DVSEC_VENDOR_DLX_VERS 0x20
+#define OCXL_DVSEC_VENDOR_RESET_RELOAD 0x38
#endif /* _OCXL_CONFIG_H_ */
--
2.25.1
^ permalink raw reply related
* [PATCH v1 5/5] mm/memory_hotplug: allow to specify a default online_type
From: David Hildenbrand @ 2020-03-11 12:30 UTC (permalink / raw)
To: linux-kernel
Cc: linux-hyperv, Baoquan He, David Hildenbrand, Greg Kroah-Hartman,
Rafael J. Wysocki, Michal Hocko, linux-mm, Andrew Morton,
Wei Yang, linuxppc-dev, Oscar Salvador
In-Reply-To: <20200311123026.16071-1-david@redhat.com>
For now, distributions implement advanced udev rules to essentially
- Don't online any hotplugged memory (s390x)
- Online all memory to ZONE_NORMAL (e.g., most virt environments like
hyperv)
- Online all memory to ZONE_MOVABLE in case the zone imbalance is taken
care of (e.g., bare metal, special virt environments)
In summary: All memory is usually onlined the same way, however, the
kernel always has to ask userspace to come up with the same answer.
E.g., HyperV always waits for a memory block to get onlined before
continuing, otherwise it might end up adding memory faster than
hotplugging it, which can result in strange OOM situations.
Let's allow to specify a default online_type, not just "online" and
"offline". This allows distributions to configure the default online_type
when booting up and be done with it.
We can now specify "offline", "online", "online_movable" and
"online_kernel" via
- "memhp_default_state=" on the kernel cmdline
- /sys/devices/systemn/memory/auto_online_blocks
just like we are able to specify for a single memory block via
/sys/devices/systemn/memory/memoryX/state
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
drivers/base/memory.c | 11 +++++------
include/linux/memory_hotplug.h | 2 ++
mm/memory_hotplug.c | 8 ++++----
3 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 8d3e16dab69f..2b09b68b9f78 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -35,7 +35,7 @@ static const char *const online_type_to_str[] = {
[MMOP_ONLINE_MOVABLE] = "online_movable",
};
-static int memhp_online_type_from_str(const char *str)
+int memhp_online_type_from_str(const char *str)
{
int i;
@@ -394,13 +394,12 @@ static ssize_t auto_online_blocks_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
- if (sysfs_streq(buf, "online"))
- memhp_default_online_type = MMOP_ONLINE;
- else if (sysfs_streq(buf, "offline"))
- memhp_default_online_type = MMOP_OFFLINE;
- else
+ const int online_type = memhp_online_type_from_str(buf);
+
+ if (online_type < 0)
return -EINVAL;
+ memhp_default_online_type = online_type;
return count;
}
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index c6e090b34c4b..ef55115320fb 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -117,6 +117,8 @@ extern int arch_add_memory(int nid, u64 start, u64 size,
struct mhp_restrictions *restrictions);
extern u64 max_mem_size;
+extern int memhp_online_type_from_str(const char *str);
+
/* Default online_type (MMOP_*) when new memory blocks are added. */
extern int memhp_default_online_type;
/* If movable_node boot option specified */
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 01443c70aa27..4a96273eafa7 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -75,10 +75,10 @@ EXPORT_SYMBOL_GPL(memhp_default_online_type);
static int __init setup_memhp_default_state(char *str)
{
- if (!strcmp(str, "online"))
- memhp_default_online_type = MMOP_ONLINE;
- else if (!strcmp(str, "offline"))
- memhp_default_online_type = MMOP_OFFLINE;
+ const int online_type = memhp_online_type_from_str(str);
+
+ if (online_type >= 0)
+ memhp_default_online_type = online_type;
return 1;
}
--
2.24.1
^ permalink raw reply related
* [PATCH v1 4/5] mm/memory_hotplug: convert memhp_auto_online to store an online_type
From: David Hildenbrand @ 2020-03-11 12:30 UTC (permalink / raw)
To: linux-kernel
Cc: linux-hyperv, K. Y. Srinivasan, Stephen Hemminger, Baoquan He,
David Hildenbrand, Greg Kroah-Hartman, Haiyang Zhang,
Rafael J. Wysocki, Wei Liu, Michal Hocko, linux-mm,
Paul Mackerras, Andrew Morton, Wei Yang, linuxppc-dev,
Thomas Gleixner, Oscar Salvador
In-Reply-To: <20200311123026.16071-1-david@redhat.com>
... and rename it to memhp_default_online_type. This is a preparation
for more detailed default online behavior.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-hyperv@vger.kernel.org
Signed-off-by: David Hildenbrand <david@redhat.com>
---
arch/powerpc/platforms/powernv/memtrace.c | 2 +-
drivers/base/memory.c | 10 ++++------
drivers/hv/hv_balloon.c | 2 +-
include/linux/memory_hotplug.h | 3 ++-
mm/memory_hotplug.c | 13 +++++++------
5 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/memtrace.c b/arch/powerpc/platforms/powernv/memtrace.c
index d6d64f8718e6..e15a600cfa4d 100644
--- a/arch/powerpc/platforms/powernv/memtrace.c
+++ b/arch/powerpc/platforms/powernv/memtrace.c
@@ -235,7 +235,7 @@ static int memtrace_online(void)
* If kernel isn't compiled with the auto online option
* we need to online the memory ourselves.
*/
- if (!memhp_auto_online) {
+ if (memhp_default_online_type == MMOP_OFFLINE) {
lock_device_hotplug();
walk_memory_blocks(ent->start, ent->size, NULL,
online_mem_block);
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 8a7f29c0bf97..8d3e16dab69f 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -386,10 +386,8 @@ static DEVICE_ATTR_RO(block_size_bytes);
static ssize_t auto_online_blocks_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- if (memhp_auto_online)
- return sprintf(buf, "online\n");
- else
- return sprintf(buf, "offline\n");
+ return sprintf(buf, "%s\n",
+ online_type_to_str[memhp_default_online_type]);
}
static ssize_t auto_online_blocks_store(struct device *dev,
@@ -397,9 +395,9 @@ static ssize_t auto_online_blocks_store(struct device *dev,
const char *buf, size_t count)
{
if (sysfs_streq(buf, "online"))
- memhp_auto_online = true;
+ memhp_default_online_type = MMOP_ONLINE;
else if (sysfs_streq(buf, "offline"))
- memhp_auto_online = false;
+ memhp_default_online_type = MMOP_OFFLINE;
else
return -EINVAL;
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index a02ce43d778d..3b90fd12e0c5 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -727,7 +727,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size,
spin_unlock_irqrestore(&dm_device.ha_lock, flags);
init_completion(&dm_device.ol_waitevent);
- dm_device.ha_waiting = !memhp_auto_online;
+ dm_device.ha_waiting = memhp_default_online_type == MMOP_OFFLINE;
nid = memory_add_physaddr_to_nid(PFN_PHYS(start_pfn));
ret = add_memory(nid, PFN_PHYS((start_pfn)),
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index c2e06ed5e0e9..c6e090b34c4b 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -117,7 +117,8 @@ extern int arch_add_memory(int nid, u64 start, u64 size,
struct mhp_restrictions *restrictions);
extern u64 max_mem_size;
-extern bool memhp_auto_online;
+/* Default online_type (MMOP_*) when new memory blocks are added. */
+extern int memhp_default_online_type;
/* If movable_node boot option specified */
extern bool movable_node_enabled;
static inline bool movable_node_is_enabled(void)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 1a00b5a37ef6..01443c70aa27 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -67,18 +67,18 @@ void put_online_mems(void)
bool movable_node_enabled = false;
#ifndef CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE
-bool memhp_auto_online;
+int memhp_default_online_type = MMOP_OFFLINE;
#else
-bool memhp_auto_online = true;
+int memhp_default_online_type = MMOP_ONLINE;
#endif
-EXPORT_SYMBOL_GPL(memhp_auto_online);
+EXPORT_SYMBOL_GPL(memhp_default_online_type);
static int __init setup_memhp_default_state(char *str)
{
if (!strcmp(str, "online"))
- memhp_auto_online = true;
+ memhp_default_online_type = MMOP_ONLINE;
else if (!strcmp(str, "offline"))
- memhp_auto_online = false;
+ memhp_default_online_type = MMOP_OFFLINE;
return 1;
}
@@ -991,6 +991,7 @@ static int check_hotplug_memory_range(u64 start, u64 size)
static int online_memory_block(struct memory_block *mem, void *arg)
{
+ mem->online_type = memhp_default_online_type;
return device_online(&mem->dev);
}
@@ -1063,7 +1064,7 @@ int __ref add_memory_resource(int nid, struct resource *res)
mem_hotplug_done();
/* online pages if requested */
- if (memhp_auto_online)
+ if (memhp_default_online_type != MMOP_OFFLINE)
walk_memory_blocks(start, size, NULL, online_memory_block);
return ret;
--
2.24.1
^ permalink raw reply related
* [PATCH v1 0/5] mm/memory_hotplug: allow to specify a default online_type
From: David Hildenbrand @ 2020-03-11 12:30 UTC (permalink / raw)
To: linux-kernel
Cc: Yumei Huang, linux-hyperv, David Hildenbrand, Michal Hocko,
linux-mm, Paul Mackerras, K. Y. Srinivasan, Wei Liu,
Stephen Hemminger, Baoquan He, Rafael J. Wysocki, Eduardo Habkost,
Haiyang Zhang, Thomas Gleixner, Wei Yang, Andrew Morton,
Oscar Salvador, Milan Zamazal, Greg Kroah-Hartman, Igor Mammedov,
Vitaly Kuznetsov, linuxppc-dev
Distributions nowadays use udev rules ([1] [2]) to specify if and
how to online hotplugged memory. The rules seem to get more complex with
many special cases. Due to the various special cases,
CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE cannot be used. All memory hotplug
is handled via udev rules.
Everytime we hotplug memory, the udev rule will come to the same
conclusion. Especially Hyper-V (but also soon virtio-mem) add a lot of
memory in separate memory blocks and wait for memory to get onlined by user
space before continuing to add more memory blocks (to not add memory faster
than it is getting onlined). This of course slows down the whole memory
hotplug process.
To make the job of distributions easier and to avoid udev rules that get
more and more complicated, let's extend the mechanism provided by
- /sys/devices/system/memory/auto_online_blocks
- "memhp_default_state=" on the kernel cmdline
to be able to specify also "online_movable" as well as "online_kernel"
=== Example /usr/libexec/config-memhotplug ===
#!/bin/bash
VIRT=`systemd-detect-virt --vm`
ARCH=`uname -p`
sense_virtio_mem() {
if [ -d "/sys/bus/virtio/drivers/virtio_mem/" ]; then
DEVICES=`find /sys/bus/virtio/drivers/virtio_mem/ -maxdepth 1 -type l | wc -l`
if [ $DEVICES != "0" ]; then
return 0
fi
fi
return 1
}
if [ ! -e "/sys/devices/system/memory/auto_online_blocks" ]; then
echo "Memory hotplug configuration support missing in the kernel"
exit 1
fi
if grep "memhp_default_state=" /proc/cmdline > /dev/null; then
echo "Memory hotplug configuration overridden in kernel cmdline (memhp_default_state=)"
exit 1
fi
if [ $VIRT == "microsoft" ]; then
echo "Detected Hyper-V on $ARCH"
# Hyper-V wants all memory in ZONE_NORMAL
ONLINE_TYPE="online_kernel"
elif sense_virtio_mem; then
echo "Detected virtio-mem on $ARCH"
# virtio-mem wants all memory in ZONE_NORMAL
ONLINE_TYPE="online_kernel"
elif [ $ARCH == "s390x" ] || [ $ARCH == "s390" ]; then
echo "Detected $ARCH"
# standby memory should not be onlined automatically
ONLINE_TYPE="offline"
elif [ $ARCH == "ppc64" ] || [ $ARCH == "ppc64le" ]; then
echo "Detected" $ARCH
# PPC64 is handled via a user space daemon AFAIK
ONLINE_TYPE="offline"
elif [ $VIRT == "none" ]; then
echo "Detected bare-metal on $ARCH"
# Bare metal users expect hotplugged memory to be unpluggable. We assume
# that ZONE imbalances on such enterpise servers cannot happen and is
# properly documented
ONLINE_TYPE="online_movable"
else
# TODO: Hypervisors that want to unplug DIMMs and can guarantee that ZONE
# imbalances won't happen
echo "Detected $VIRT on $ARCH"
# Usually, ballooning is used in virtual environments, so memory should go to
# ZONE_NORMAL. However, sometimes "movable_node" is relevant.
ONLINE_TYPE="online"
fi
echo "Selected online_type:" $ONLINE_TYPE
# Configure what to do with memory that will be hotplugged in the future
echo $ONLINE_TYPE 2>/dev/null > /sys/devices/system/memory/auto_online_blocks
if [ $? != "0" ]; then
echo "Memory hotplug cannot be configured (e.g., old kernel or missing permissions)"
# A backup udev rule should handle old kernels if necessary
exit 1
fi
# Process all already pluggedd blocks (e.g., DIMMs, but also Hyper-V or virtio-mem)
if [ $ONLINE_TYPE != "offline" ]; then
for MEMORY in /sys/devices/system/memory/memory*; do
STATE=`cat $MEMORY/state`
if [ $STATE == "offline" ]; then
echo $ONLINE_TYPE > $MEMORY/state
fi
done
fi
=== Example /usr/lib/systemd/system/config-memhotplug.service ===
[Unit]
Description=Configure memory hotplug behavior
DefaultDependencies=no
Conflicts=shutdown.target
Before=sysinit.target shutdown.target
After=systemd-modules-load.service
ConditionPathExists=|/sys/devices/system/memory/auto_online_blocks
[Service]
ExecStart=/usr/libexec/config-memhotplug
Type=oneshot
TimeoutSec=0
RemainAfterExit=yes
[Install]
WantedBy=sysinit.target
=== Example modification to the 40-redhat.rules [2] ===
diff --git a/40-redhat.rules b/40-redhat.rules-new
index 2c690e5..168fd03 100644
--- a/40-redhat.rules
+++ b/40-redhat.rules-new
@@ -6,6 +6,9 @@ SUBSYSTEM=="cpu", ACTION=="add", TEST=="online", ATTR{online}=="0", ATTR{online}
# Memory hotadd request
SUBSYSTEM!="memory", GOTO="memory_hotplug_end"
ACTION!="add", GOTO="memory_hotplug_end"
+# memory hotplug behavior configured
+PROGRAM=="grep online /sys/devices/system/memory/auto_online_blocks", GOTO="memory_hotplug_end"
+
PROGRAM="/bin/uname -p", RESULT=="s390*", GOTO="memory_hotplug_end"
ENV{.state}="online"
===
[1] https://github.com/lnykryn/systemd-rhel/pull/281
[2] https://github.com/lnykryn/systemd-rhel/blob/staging/rules/40-redhat.rules
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Yumei Huang <yuhuang@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Milan Zamazal <mzamazal@redhat.com>
David Hildenbrand (5):
drivers/base/memory: rename MMOP_ONLINE_KEEP to MMOP_ONLINE
drivers/base/memory: map MMOP_OFFLINE to 0
drivers/base/memory: store mapping between MMOP_* and string in an
array
mm/memory_hotplug: convert memhp_auto_online to store an online_type
mm/memory_hotplug: allow to specify a default online_type
arch/powerpc/platforms/powernv/memtrace.c | 2 +-
drivers/base/memory.c | 71 ++++++++++++-----------
drivers/hv/hv_balloon.c | 2 +-
include/linux/memory_hotplug.h | 13 ++++-
mm/memory_hotplug.c | 17 +++---
5 files changed, 58 insertions(+), 47 deletions(-)
--
2.24.1
^ permalink raw reply related
* [PATCH v1 2/5] drivers/base/memory: map MMOP_OFFLINE to 0
From: David Hildenbrand @ 2020-03-11 12:30 UTC (permalink / raw)
To: linux-kernel
Cc: linux-hyperv, Baoquan He, David Hildenbrand, Greg Kroah-Hartman,
Rafael J. Wysocki, Michal Hocko, linux-mm, Andrew Morton,
Wei Yang, linuxppc-dev, Oscar Salvador
In-Reply-To: <20200311123026.16071-1-david@redhat.com>
I have no idea why we have to start at -1. Just treat 0 as the special
case. Clarify a comment (which was wrong, when we come via
device_online() the first time, the online_type would have been 0 /
MEM_ONLINE). The default is now always MMOP_OFFLINE.
This is a preparation to use the online_type as an array index.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
drivers/base/memory.c | 11 ++++-------
include/linux/memory_hotplug.h | 2 +-
2 files changed, 5 insertions(+), 8 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 8c5ce42c0fc3..e7e77cafef80 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -211,17 +211,14 @@ static int memory_subsys_online(struct device *dev)
return 0;
/*
- * If we are called from state_store(), online_type will be
- * set >= 0 Otherwise we were called from the device online
- * attribute and need to set the online_type.
+ * When called via device_online() without configuring the online_type,
+ * we want to default to MMOP_ONLINE.
*/
- if (mem->online_type < 0)
+ if (mem->online_type == MMOP_OFFLINE)
mem->online_type = MMOP_ONLINE;
ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
-
- /* clear online_type */
- mem->online_type = -1;
+ mem->online_type = MMOP_OFFLINE;
return ret;
}
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 261dbf010d5d..c2e06ed5e0e9 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -48,7 +48,7 @@ enum {
/* Types for control the zone type of onlined and offlined memory */
enum {
/* Offline the memory. */
- MMOP_OFFLINE = -1,
+ MMOP_OFFLINE = 0,
/* Online the memory. Zone depends, see default_zone_for_pfn(). */
MMOP_ONLINE,
/* Online the memory to ZONE_NORMAL. */
--
2.24.1
^ permalink raw reply related
* [PATCH v1 3/5] drivers/base/memory: store mapping between MMOP_* and string in an array
From: David Hildenbrand @ 2020-03-11 12:30 UTC (permalink / raw)
To: linux-kernel
Cc: linux-hyperv, Baoquan He, David Hildenbrand, Greg Kroah-Hartman,
Rafael J. Wysocki, Michal Hocko, linux-mm, Andrew Morton,
Wei Yang, linuxppc-dev, Oscar Salvador
In-Reply-To: <20200311123026.16071-1-david@redhat.com>
Let's use a simple array which we can reuse soon. While at it, move the
string->mmop conversion out of the device hotplug lock.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
drivers/base/memory.c | 38 +++++++++++++++++++++++---------------
1 file changed, 23 insertions(+), 15 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index e7e77cafef80..8a7f29c0bf97 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -28,6 +28,24 @@
#define MEMORY_CLASS_NAME "memory"
+static const char *const online_type_to_str[] = {
+ [MMOP_OFFLINE] = "offline",
+ [MMOP_ONLINE] = "online",
+ [MMOP_ONLINE_KERNEL] = "online_kernel",
+ [MMOP_ONLINE_MOVABLE] = "online_movable",
+};
+
+static int memhp_online_type_from_str(const char *str)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(online_type_to_str); i++) {
+ if (sysfs_streq(str, online_type_to_str[i]))
+ return i;
+ }
+ return -EINVAL;
+}
+
#define to_memory_block(dev) container_of(dev, struct memory_block, dev)
static int sections_per_block;
@@ -236,26 +254,17 @@ static int memory_subsys_offline(struct device *dev)
static ssize_t state_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
+ const int online_type = memhp_online_type_from_str(buf);
struct memory_block *mem = to_memory_block(dev);
- int ret, online_type;
+ int ret;
+
+ if (online_type < 0)
+ return -EINVAL;
ret = lock_device_hotplug_sysfs();
if (ret)
return ret;
- if (sysfs_streq(buf, "online_kernel"))
- online_type = MMOP_ONLINE_KERNEL;
- else if (sysfs_streq(buf, "online_movable"))
- online_type = MMOP_ONLINE_MOVABLE;
- else if (sysfs_streq(buf, "online"))
- online_type = MMOP_ONLINE;
- else if (sysfs_streq(buf, "offline"))
- online_type = MMOP_OFFLINE;
- else {
- ret = -EINVAL;
- goto err;
- }
-
switch (online_type) {
case MMOP_ONLINE_KERNEL:
case MMOP_ONLINE_MOVABLE:
@@ -271,7 +280,6 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
ret = -EINVAL; /* should never happen */
}
-err:
unlock_device_hotplug();
if (ret < 0)
--
2.24.1
^ permalink raw reply related
* [PATCH v1 1/5] drivers/base/memory: rename MMOP_ONLINE_KEEP to MMOP_ONLINE
From: David Hildenbrand @ 2020-03-11 12:30 UTC (permalink / raw)
To: linux-kernel
Cc: linux-hyperv, Baoquan He, David Hildenbrand, Greg Kroah-Hartman,
Rafael J. Wysocki, Michal Hocko, linux-mm, Andrew Morton,
Wei Yang, linuxppc-dev, Oscar Salvador
In-Reply-To: <20200311123026.16071-1-david@redhat.com>
The name is misleading. Let's just name it like the online_type name we
expose to user space ("online").
Add some documentation to the types.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
---
drivers/base/memory.c | 9 +++++----
include/linux/memory_hotplug.h | 6 +++++-
2 files changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 6448c9ece2cb..8c5ce42c0fc3 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -216,7 +216,7 @@ static int memory_subsys_online(struct device *dev)
* attribute and need to set the online_type.
*/
if (mem->online_type < 0)
- mem->online_type = MMOP_ONLINE_KEEP;
+ mem->online_type = MMOP_ONLINE;
ret = memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE);
@@ -251,7 +251,7 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
else if (sysfs_streq(buf, "online_movable"))
online_type = MMOP_ONLINE_MOVABLE;
else if (sysfs_streq(buf, "online"))
- online_type = MMOP_ONLINE_KEEP;
+ online_type = MMOP_ONLINE;
else if (sysfs_streq(buf, "offline"))
online_type = MMOP_OFFLINE;
else {
@@ -262,7 +262,7 @@ static ssize_t state_store(struct device *dev, struct device_attribute *attr,
switch (online_type) {
case MMOP_ONLINE_KERNEL:
case MMOP_ONLINE_MOVABLE:
- case MMOP_ONLINE_KEEP:
+ case MMOP_ONLINE:
/* mem->online_type is protected by device_hotplug_lock */
mem->online_type = online_type;
ret = device_online(&mem->dev);
@@ -342,7 +342,8 @@ static ssize_t valid_zones_show(struct device *dev,
}
nid = mem->nid;
- default_zone = zone_for_pfn_range(MMOP_ONLINE_KEEP, nid, start_pfn, nr_pages);
+ default_zone = zone_for_pfn_range(MMOP_ONLINE, nid, start_pfn,
+ nr_pages);
strcat(buf, default_zone->name);
print_allowed_zone(buf, nid, start_pfn, nr_pages, MMOP_ONLINE_KERNEL,
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index f4d59155f3d4..261dbf010d5d 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -47,9 +47,13 @@ enum {
/* Types for control the zone type of onlined and offlined memory */
enum {
+ /* Offline the memory. */
MMOP_OFFLINE = -1,
- MMOP_ONLINE_KEEP,
+ /* Online the memory. Zone depends, see default_zone_for_pfn(). */
+ MMOP_ONLINE,
+ /* Online the memory to ZONE_NORMAL. */
MMOP_ONLINE_KERNEL,
+ /* Online the memory to ZONE_MOVABLE. */
MMOP_ONLINE_MOVABLE,
};
--
2.24.1
^ permalink raw reply related
* [PATCH 3/3] mm/page_alloc: Keep memoryless cpuless node 0 offline
From: Srikar Dronamraju @ 2020-03-11 11:02 UTC (permalink / raw)
To: Andrew Morton, Michael Ellerman
Cc: Michal Hocko, Srikar Dronamraju, Linus Torvalds, linux-kernel,
linux-mm, Mel Gorman, Kirill A. Shutemov, Christopher Lameter,
linuxppc-dev, Vlastimil Babka
In-Reply-To: <20200311110237.5731-1-srikar@linux.vnet.ibm.com>
Currently Linux kernel with CONFIG_NUMA on a system with multiple
possible nodes, marks node 0 as online at boot. However in practice,
there are systems which have node 0 as memoryless and cpuless.
This can cause numa_balancing to be enabled on systems with only one node
with memory and CPUs. The existence of this dummy node which is cpuless and
memoryless node can confuse users/scripts looking at output of lscpu /
numactl.
Lets stop assuming that Node 0 is always online.
v5.6-rc4
available: 2 nodes (0,2)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 2 cpus: 0 1 2 3 4 5 6 7
node 2 size: 32625 MB
node 2 free: 31490 MB
node distances:
node 0 2
0: 10 20
2: 20 10
proc and sys files
------------------
/sys/devices/system/node/online: 0,2
/proc/sys/kernel/numa_balancing: 1
/sys/devices/system/node/has_cpu: 2
/sys/devices/system/node/has_memory: 2
/sys/devices/system/node/has_normal_memory: 2
/sys/devices/system/node/possible: 0-31
v5.6-rc4 + patch
------------------
available: 1 nodes (2)
node 2 cpus: 0 1 2 3 4 5 6 7
node 2 size: 32625 MB
node 2 free: 31487 MB
node distances:
node 2
2: 10
proc and sys files
------------------
/sys/devices/system/node/online: 2
/proc/sys/kernel/numa_balancing: 0
/sys/devices/system/node/has_cpu: 2
/sys/devices/system/node/has_memory: 2
/sys/devices/system/node/has_normal_memory: 2
/sys/devices/system/node/possible: 0-31
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Christopher Lameter <cl@linux.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
mm/page_alloc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 3c4eb75..68e635f4 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -116,8 +116,10 @@ struct pcpu_drain {
*/
nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
[N_POSSIBLE] = NODE_MASK_ALL,
+#ifdef CONFIG_NUMA
+ [N_ONLINE] = NODE_MASK_NONE,
+#else
[N_ONLINE] = { { [0] = 1UL } },
-#ifndef CONFIG_NUMA
[N_NORMAL_MEMORY] = { { [0] = 1UL } },
#ifdef CONFIG_HIGHMEM
[N_HIGH_MEMORY] = { { [0] = 1UL } },
--
1.8.3.1
^ permalink raw reply related
* Re: [PATCH 1/3] powerpc/numa: Set numa_node for all possible cpus
From: Michal Hocko @ 2020-03-11 11:57 UTC (permalink / raw)
To: Srikar Dronamraju
Cc: Linus Torvalds, linux-kernel, linux-mm, Mel Gorman,
Kirill A. Shutemov, Andrew Morton, linuxppc-dev,
Christopher Lameter, Vlastimil Babka
In-Reply-To: <20200311110237.5731-2-srikar@linux.vnet.ibm.com>
On Wed 11-03-20 16:32:35, Srikar Dronamraju wrote:
> A Powerpc system with multiple possible nodes and with CONFIG_NUMA
> enabled always used to have a node 0, even if node 0 does not any cpus
> or memory attached to it. As per PAPR, node affinity of a cpu is only
> available once its present / online. For all cpus that are possible but
> not present, cpu_to_node() would point to node 0.
>
> To ensure a cpuless, memoryless dummy node is not online, powerpc need
> to make sure all possible but not present cpu_to_node are set to a
> proper node.
Just curious, is this somehow related to
http://lkml.kernel.org/r/20200227182650.GG3771@dhcp22.suse.cz?
> Cc: linuxppc-dev@lists.ozlabs.org
> Cc: linux-mm@kvack.org
> Cc: linux-kernel@vger.kernel.org
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: Mel Gorman <mgorman@suse.de>
> Cc: Vlastimil Babka <vbabka@suse.cz>
> Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
> Cc: Christopher Lameter <cl@linux.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
> ---
> arch/powerpc/mm/numa.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
> index 8a399db..54dcd49 100644
> --- a/arch/powerpc/mm/numa.c
> +++ b/arch/powerpc/mm/numa.c
> @@ -931,8 +931,20 @@ void __init mem_topology_setup(void)
>
> reset_numa_cpu_lookup_table();
>
> - for_each_present_cpu(cpu)
> - numa_setup_cpu(cpu);
> + for_each_possible_cpu(cpu) {
> + /*
> + * Powerpc with CONFIG_NUMA always used to have a node 0,
> + * even if it was memoryless or cpuless. For all cpus that
> + * are possible but not present, cpu_to_node() would point
> + * to node 0. To remove a cpuless, memoryless dummy node,
> + * powerpc need to make sure all possible but not present
> + * cpu_to_node are set to a proper node.
> + */
> + if (cpu_present(cpu))
> + numa_setup_cpu(cpu);
> + else
> + set_cpu_numa_node(cpu, first_online_node);
> + }
> }
>
> void __init initmem_init(void)
> --
> 1.8.3.1
--
Michal Hocko
SUSE Labs
^ permalink raw reply
* [PATCH 2/3] powerpc/numa: Prefer node id queried from vphn
From: Srikar Dronamraju @ 2020-03-11 11:02 UTC (permalink / raw)
To: Andrew Morton, Michael Ellerman
Cc: Michal Hocko, Srikar Dronamraju, Linus Torvalds, linux-kernel,
linux-mm, Mel Gorman, Kirill A. Shutemov, Christopher Lameter,
linuxppc-dev, Vlastimil Babka
In-Reply-To: <20200311110237.5731-1-srikar@linux.vnet.ibm.com>
Node id queried from the static device tree may not
be correct. For example: it may always show 0 on a shared processor.
Hence prefer the node id queried from vphn and fallback on the device tree
based node id if vphn query fails.
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Christopher Lameter <cl@linux.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
arch/powerpc/mm/numa.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 54dcd49..8735fed 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -719,20 +719,20 @@ static int __init parse_numa_properties(void)
*/
for_each_present_cpu(i) {
struct device_node *cpu;
- int nid;
-
- cpu = of_get_cpu_node(i, NULL);
- BUG_ON(!cpu);
- nid = of_node_to_nid_single(cpu);
- of_node_put(cpu);
+ int nid = vphn_get_nid(i);
/*
* Don't fall back to default_nid yet -- we will plug
* cpus into nodes once the memory scan has discovered
* the topology.
*/
- if (nid < 0)
- continue;
+ if (nid == NUMA_NO_NODE) {
+ cpu = of_get_cpu_node(i, NULL);
+ if (cpu) {
+ nid = of_node_to_nid_single(cpu);
+ of_node_put(cpu);
+ }
+ }
node_set_online(nid);
}
--
1.8.3.1
^ permalink raw reply related
* [PATCH 1/3] powerpc/numa: Set numa_node for all possible cpus
From: Srikar Dronamraju @ 2020-03-11 11:02 UTC (permalink / raw)
To: Andrew Morton, Michael Ellerman
Cc: Michal Hocko, Srikar Dronamraju, Linus Torvalds, linux-kernel,
linux-mm, Mel Gorman, Kirill A. Shutemov, Christopher Lameter,
linuxppc-dev, Vlastimil Babka
In-Reply-To: <20200311110237.5731-1-srikar@linux.vnet.ibm.com>
A Powerpc system with multiple possible nodes and with CONFIG_NUMA
enabled always used to have a node 0, even if node 0 does not any cpus
or memory attached to it. As per PAPR, node affinity of a cpu is only
available once its present / online. For all cpus that are possible but
not present, cpu_to_node() would point to node 0.
To ensure a cpuless, memoryless dummy node is not online, powerpc need
to make sure all possible but not present cpu_to_node are set to a
proper node.
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Christopher Lameter <cl@linux.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
---
arch/powerpc/mm/numa.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 8a399db..54dcd49 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -931,8 +931,20 @@ void __init mem_topology_setup(void)
reset_numa_cpu_lookup_table();
- for_each_present_cpu(cpu)
- numa_setup_cpu(cpu);
+ for_each_possible_cpu(cpu) {
+ /*
+ * Powerpc with CONFIG_NUMA always used to have a node 0,
+ * even if it was memoryless or cpuless. For all cpus that
+ * are possible but not present, cpu_to_node() would point
+ * to node 0. To remove a cpuless, memoryless dummy node,
+ * powerpc need to make sure all possible but not present
+ * cpu_to_node are set to a proper node.
+ */
+ if (cpu_present(cpu))
+ numa_setup_cpu(cpu);
+ else
+ set_cpu_numa_node(cpu, first_online_node);
+ }
}
void __init initmem_init(void)
--
1.8.3.1
^ permalink raw reply related
* [PATCH 0/3] Offline memoryless cpuless node 0
From: Srikar Dronamraju @ 2020-03-11 11:02 UTC (permalink / raw)
To: Andrew Morton, Michael Ellerman
Cc: Michal Hocko, Srikar Dronamraju, Linus Torvalds, linux-kernel,
linux-mm, Mel Gorman, Kirill A. Shutemov, Christopher Lameter,
linuxppc-dev, Vlastimil Babka
Linux kernel configured with CONFIG_NUMA on a system with multiple
possible nodes, marks node 0 as online at boot. However in practice,
there are systems which have node 0 as memoryless and cpuless.
This can cause
1. numa_balancing to be enabled on systems with only one online node.
2. Existence of dummy (cpuless and memoryless) node which can confuse
users/scripts looking at output of lscpu / numactl.
This patchset wants to correct this anomaly.
This should only affect systems that have CONFIG_MEMORYLESS_NODES.
Currently there are only 2 architectures ia64 and powerpc that have this
config.
v5.6-rc4
available: 2 nodes (0,2)
node 0 cpus:
node 0 size: 0 MB
node 0 free: 0 MB
node 2 cpus: 0 1 2 3 4 5 6 7
node 2 size: 32625 MB
node 2 free: 31490 MB
node distances:
node 0 2
0: 10 20
2: 20 10
proc and sys files
------------------
/sys/devices/system/node/online: 0,2
/proc/sys/kernel/numa_balancing: 1
/sys/devices/system/node/has_cpu: 2
/sys/devices/system/node/has_memory: 2
/sys/devices/system/node/has_normal_memory: 2
/sys/devices/system/node/possible: 0-31
v5.6-rc4 + patches
------------------
available: 1 nodes (2)
node 2 cpus: 0 1 2 3 4 5 6 7
node 2 size: 32625 MB
node 2 free: 31487 MB
node distances:
node 2
2: 10
proc and sys files
------------------
/sys/devices/system/node/online: 2
/proc/sys/kernel/numa_balancing: 0
/sys/devices/system/node/has_cpu: 2
/sys/devices/system/node/has_memory: 2
/sys/devices/system/node/has_normal_memory: 2
/sys/devices/system/node/possible: 0-31
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Christopher Lameter <cl@linux.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Srikar Dronamraju (3):
powerpc/numa: Set numa_node for all possible cpus
powerpc/numa: Prefer node id queried from vphn
mm/page_alloc: Keep memoryless cpuless node 0 offline
arch/powerpc/mm/numa.c | 32 ++++++++++++++++++++++----------
mm/page_alloc.c | 4 +++-
2 files changed, 25 insertions(+), 11 deletions(-)
--
1.8.3.1
^ permalink raw reply
* [PATCH v2] powerpc test_emulate_step: fix DS operand in ld encoding to appropriate value
From: Balamuruhan S @ 2020-03-11 10:24 UTC (permalink / raw)
To: mpe
Cc: ravi.bangoria, jniethe5, Balamuruhan S, paulus, sandipan,
naveen.n.rao, linuxppc-dev
ld instruction should have 14 bit immediate field (DS) concatenated with
0b00 on the right, encode it accordingly. Introduce macro `IMM_DS()`
to encode DS form instructions with 14 bit immediate field.
Fixes: 4ceae137bdab ("powerpc: emulate_step() tests for load/store instructions")
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Balamuruhan S <bala24@linux.ibm.com>
---
arch/powerpc/lib/test_emulate_step.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
---
changes in v2:
-------------
* squash the commits as per Christophe's review comment
diff --git a/arch/powerpc/lib/test_emulate_step.c b/arch/powerpc/lib/test_emulate_step.c
index 42347067739c..007292a1ad01 100644
--- a/arch/powerpc/lib/test_emulate_step.c
+++ b/arch/powerpc/lib/test_emulate_step.c
@@ -13,19 +13,20 @@
#include <asm/code-patching.h>
#define IMM_L(i) ((uintptr_t)(i) & 0xffff)
+#define IMM_DS(i) ((uintptr_t)(i) & 0xfffc)
/*
* Defined with TEST_ prefix so it does not conflict with other
* definitions.
*/
#define TEST_LD(r, base, i) (PPC_INST_LD | ___PPC_RT(r) | \
- ___PPC_RA(base) | IMM_L(i))
+ ___PPC_RA(base) | IMM_DS(i))
#define TEST_LWZ(r, base, i) (PPC_INST_LWZ | ___PPC_RT(r) | \
___PPC_RA(base) | IMM_L(i))
#define TEST_LWZX(t, a, b) (PPC_INST_LWZX | ___PPC_RT(t) | \
___PPC_RA(a) | ___PPC_RB(b))
#define TEST_STD(r, base, i) (PPC_INST_STD | ___PPC_RS(r) | \
- ___PPC_RA(base) | ((i) & 0xfffc))
+ ___PPC_RA(base) | IMM_DS(i))
#define TEST_LDARX(t, a, b, eh) (PPC_INST_LDARX | ___PPC_RT(t) | \
___PPC_RA(a) | ___PPC_RB(b) | \
__PPC_EH(eh))
base-commit: 5aa19adac1f3152a5fd3b865a1ab46bb845d3696
--
2.24.1
^ permalink raw reply related
* [PATCH v3 6/6] pseries/sysfs: Minimise IPI noise while reading [idle_][s]purr
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
In-Reply-To: <1583919461-27405-1-git-send-email-ego@linux.vnet.ibm.com>
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
Currently purr, spurr, idle_purr, idle_spurr are exposed for every CPU
via the sysfs interface
/sys/devices/system/cpu/cpuX/[idle_][s]purr. Each sysfs read currently
generates an IPI to obtain the desired value from the target CPU X.
Since these aforementioned sysfs files are typically read one after
another, we end up generating 4 IPIs per CPU in a short duration.
In order to minimize the IPI noise, this patch caches the values of
all the four entities whenever one of them is read. If subsequently
any of these are read within the next 10ms, the cached value is
returned. With this, we will generate at most one IPI every 10ms for
every CPU.
Test-results: While reading the four sysfs files back-to-back for a
given CPU every second for 100 seconds.
Without the patch:
16 [XICS 2 Edge IPI] = 422 times
DBL [Doorbell interrupts] = 13 times
Total : 435 IPIs.
With the patch:
16 [XICS 2 Edge IPI] = 111 times
DBL [Doorbell interrupts] = 17 times
Total : 128 IPIs.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
arch/powerpc/kernel/sysfs.c | 109 ++++++++++++++++++++++++++++++++++++--------
1 file changed, 90 insertions(+), 19 deletions(-)
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c
index c9ddb83..db8fc90 100644
--- a/arch/powerpc/kernel/sysfs.c
+++ b/arch/powerpc/kernel/sysfs.c
@@ -586,8 +586,6 @@ void ppc_enable_pmcs(void)
* SPRs which are not related to PMU.
*/
#ifdef CONFIG_PPC64
-SYSFS_SPRSETUP(purr, SPRN_PURR);
-SYSFS_SPRSETUP(spurr, SPRN_SPURR);
SYSFS_SPRSETUP(pir, SPRN_PIR);
SYSFS_SPRSETUP(tscr, SPRN_TSCR);
@@ -596,8 +594,6 @@ void ppc_enable_pmcs(void)
enable write when needed with a separate function.
Lets be conservative and default to pseries.
*/
-static DEVICE_ATTR(spurr, 0400, show_spurr, NULL);
-static DEVICE_ATTR(purr, 0400, show_purr, store_purr);
static DEVICE_ATTR(pir, 0400, show_pir, NULL);
static DEVICE_ATTR(tscr, 0600, show_tscr, store_tscr);
#endif /* CONFIG_PPC64 */
@@ -761,39 +757,114 @@ static void create_svm_file(void)
}
#endif /* CONFIG_PPC_SVM */
-static void read_idle_purr(void *val)
+/*
+ * The duration (in ms) from the last IPI to the target CPU until
+ * which a cached value of purr, spurr, idle_purr, idle_spurr can be
+ * reported to the user on a corresponding sysfs file read. Beyond
+ * this duration, fresh values need to be obtained by sending IPIs to
+ * the target CPU when the sysfs files are read.
+ */
+static unsigned long util_stats_staleness_tolerance_ms = 10;
+struct util_acct_stats {
+ u64 latest_purr;
+ u64 latest_spurr;
+ u64 latest_idle_purr;
+ u64 latest_idle_spurr;
+ unsigned long last_update_jiffies;
+};
+
+DEFINE_PER_CPU(struct util_acct_stats, util_acct_stats);
+
+static void update_util_acct_stats(void *ptr)
{
- u64 *ret = val;
+ struct util_acct_stats *stats = ptr;
- *ret = read_this_idle_purr();
+ stats->latest_purr = mfspr(SPRN_PURR);
+ stats->latest_spurr = mfspr(SPRN_SPURR);
+ stats->latest_idle_purr = read_this_idle_purr();
+ stats->latest_idle_spurr = read_this_idle_spurr();
+ stats->last_update_jiffies = jiffies;
}
-static ssize_t idle_purr_show(struct device *dev,
- struct device_attribute *attr, char *buf)
+struct util_acct_stats *get_util_stats_ptr(int cpu)
+{
+ struct util_acct_stats *stats = per_cpu_ptr(&util_acct_stats, cpu);
+ unsigned long delta_jiffies;
+
+ delta_jiffies = jiffies - stats->last_update_jiffies;
+
+ /*
+ * If we have a recent enough data, reuse that instead of
+ * sending an IPI.
+ */
+ if (jiffies_to_msecs(delta_jiffies) < util_stats_staleness_tolerance_ms)
+ return stats;
+
+ smp_call_function_single(cpu, update_util_acct_stats, stats, 1);
+ return stats;
+}
+
+static ssize_t show_purr(struct device *dev,
+ struct device_attribute *attr, char *buf)
{
struct cpu *cpu = container_of(dev, struct cpu, dev);
- u64 val;
+ struct util_acct_stats *stats;
- smp_call_function_single(cpu->dev.id, read_idle_purr, &val, 1);
- return sprintf(buf, "%llx\n", val);
+ stats = get_util_stats_ptr(cpu->dev.id);
+ return sprintf(buf, "%llx\n", stats->latest_purr);
}
-static DEVICE_ATTR(idle_purr, 0400, idle_purr_show, NULL);
-static void read_idle_spurr(void *val)
+static void write_purr(void *val)
{
- u64 *ret = val;
+ mtspr(SPRN_PURR, *(unsigned long *)val);
+}
- *ret = read_this_idle_spurr();
+static ssize_t __used store_purr(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, dev);
+ unsigned long val;
+ int ret = kstrtoul(buf, 16, &val);
+
+ if (ret != 0)
+ return -EINVAL;
+
+ smp_call_function_single(cpu->dev.id, write_purr, &val, 1);
+ return count;
+}
+static DEVICE_ATTR(purr, 0400, show_purr, store_purr);
+
+static ssize_t show_spurr(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, dev);
+ struct util_acct_stats *stats;
+
+ stats = get_util_stats_ptr(cpu->dev.id);
+ return sprintf(buf, "%llx\n", stats->latest_spurr);
}
+static DEVICE_ATTR(spurr, 0400, show_spurr, NULL);
+
+static ssize_t idle_purr_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, dev);
+ struct util_acct_stats *stats;
+
+ stats = get_util_stats_ptr(cpu->dev.id);
+ return sprintf(buf, "%llx\n", stats->latest_idle_purr);
+}
+static DEVICE_ATTR(idle_purr, 0400, idle_purr_show, NULL);
static ssize_t idle_spurr_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct cpu *cpu = container_of(dev, struct cpu, dev);
- u64 val;
+ struct util_acct_stats *stats;
- smp_call_function_single(cpu->dev.id, read_idle_spurr, &val, 1);
- return sprintf(buf, "%llx\n", val);
+ stats = get_util_stats_ptr(cpu->dev.id);
+ return sprintf(buf, "%llx\n", stats->latest_idle_spurr);
}
static DEVICE_ATTR(idle_spurr, 0400, idle_spurr_show, NULL);
--
1.9.4
^ permalink raw reply related
* [PATCH v3 0/6] Track and expose idle PURR and SPURR ticks
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
Hi,
This is the third version of the patches to track and expose idle PURR
and SPURR ticks. These patches are required by tools such as lparstat
to compute system utilization for capacity planning purposes.
The previous versions can be found here:
v2: https://lkml.org/lkml/2020/2/21/21
v1: https://lore.kernel.org/patchwork/cover/1159341/
They key changes from v2 are:
- The prolog and epilog functions have been named
pseries_idle_prolog() and pseries_idle_epilog() respectively to
indicate their pseries specific nature.
- Fixed the Documentation for
/sys/devices/system/cpu/cpuX/idle_spurr as pointed out by
Nathan Lynch.
- Introduces a patch (Patch 6/6) to send an IPI in order to read
and cache the values of purr, spurr, idle_purr and idle_spurr of
the target CPU when any one of them is read via sysfs. These
cached values will be presented if any of these sysfs are read
within the next 10ms. If these sysfs files are read after 10ms
from the earlier IPI, a fresh IPI is issued to read and cache
the values again. This minimizes the number of IPIs required to
be sent when these values are read back-to-back via the sysfs
interface.
Test-results: While reading the four sysfs files back-to-back for a
given CPU every second for 100 seconds.
Without patch 6/6 (Without caching):
16 [XICS 2 Edge IPI] = 422 times
DBL [Doorbell interrupts] = 13 times
Total : 435 IPIs.
With patch 6/6 (With caching):
16 [XICS 2 Edge IPI] = 111 times
DBL [Doorbell interrupts] = 17 times
Total : 128 IPIs.
Motivation:
===========
On PSeries LPARs, the data centers planners desire a more accurate
view of system utilization per resource such as CPU to plan the system
capacity requirements better. Such accuracy can be obtained by reading
PURR/SPURR registers for CPU resource utilization.
Tools such as lparstat which are used to compute the utilization need
to know [S]PURR ticks when the cpu was busy or idle. The [S]PURR
counters are already exposed through sysfs. We already account for
PURR ticks when we go to idle so that we can update the VPA area. This
patchset extends support to account for SPURR ticks when idle, and
expose both via per-cpu sysfs files.
These patches are required for enhancement to the lparstat utility
that compute the CPU utilization based on PURR and SPURR which can be
found here :
https://groups.google.com/forum/#!topic/powerpc-utils-devel/fYRo69xO9r4
With the patches, when lparstat is run on a LPAR running CPU-Hogs,
=========================================================================
sudo ./src/lparstat -E 1 3
System Configuration
type=Dedicated mode=Capped smt=8 lcpu=2 mem=4834176 kB cpus=0 ent=2.00
---Actual--- -Normalized-
%busy %idle Frequency %busy %idle
------ ------ ------------- ------ ------
1 99.99 0.00 3.35GHz[111%] 110.99 0.00
2 100.00 0.00 3.35GHz[111%] 111.00 0.00
3 100.00 0.00 3.35GHz[111%] 111.00 0.00
=========================================================================
When lparstat is run on an LPAR that is idle,
=========================================================================
$ sudo ./src/lparstat -E 1 3
System Configuration
type=Dedicated mode=Capped smt=8 lcpu=2 mem=4834176 kB cpus=0 ent=2.00
---Actual--- -Normalized-
%busy %idle Frequency %busy %idle
------ ------ ------------- ------ ------
1 0.71 99.30 2.18GHz[ 72%] 0.53 71.48
2 0.56 99.44 2.11GHz[ 70%] 0.43 69.57
3 0.54 99.46 2.11GHz[ 70%] 0.43 69.57
=========================================================================
Gautham R. Shenoy (6):
powerpc: Move idle_loop_prolog()/epilog() functions to header file
powerpc/idle: Add accessor function to always read latest idle PURR
powerpc/pseries: Account for SPURR ticks on idle CPUs
powerpc/sysfs: Show idle_purr and idle_spurr for every CPU
Documentation: Document sysfs interfaces purr, spurr, idle_purr, idle_spurr
pseries/sysfs: Minimise IPI noise while reading [idle_][s]purr
Documentation/ABI/testing/sysfs-devices-system-cpu | 39 ++++++
arch/powerpc/include/asm/idle.h | 89 ++++++++++++++
arch/powerpc/kernel/sysfs.c | 133 +++++++++++++++++++--
arch/powerpc/platforms/pseries/setup.c | 8 +-
drivers/cpuidle/cpuidle-pseries.c | 39 ++----
5 files changed, 267 insertions(+), 41 deletions(-)
create mode 100644 arch/powerpc/include/asm/idle.h
--
1.9.4
^ permalink raw reply
* [PATCH v3 1/6] powerpc: Move idle_loop_prolog()/epilog() functions to header file
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
In-Reply-To: <1583919461-27405-1-git-send-email-ego@linux.vnet.ibm.com>
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
Currently prior to entering an idle state on a Linux Guest, the
pseries cpuidle driver implement an idle_loop_prolog() and
idle_loop_epilog() functions which ensure that idle_purr is correctly
computed, and the hypervisor is informed that the CPU cycles have been
donated.
These prolog and epilog functions are also required in the default
idle call, i.e pseries_lpar_idle(). Hence move these accessor
functions to a common header file and call them from
pseries_lpar_idle(). Since the existing header files such as
asm/processor.h have enough clutter, create a new header file
asm/idle.h. Finally rename idle_loop_prolog() and idle_loop_epilog()
to pseries_idle_prolog() and pseries_idle_epilog() as they are only
relavent for on pseries guests.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/idle.h | 28 ++++++++++++++++++++++++++
arch/powerpc/platforms/pseries/setup.c | 7 +++++--
drivers/cpuidle/cpuidle-pseries.c | 36 +++++++---------------------------
3 files changed, 40 insertions(+), 31 deletions(-)
create mode 100644 arch/powerpc/include/asm/idle.h
diff --git a/arch/powerpc/include/asm/idle.h b/arch/powerpc/include/asm/idle.h
new file mode 100644
index 0000000..e838ea5
--- /dev/null
+++ b/arch/powerpc/include/asm/idle.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _ASM_POWERPC_IDLE_H
+#define _ASM_POWERPC_IDLE_H
+#include <asm/runlatch.h>
+
+static inline void pseries_idle_prolog(unsigned long *in_purr)
+{
+ ppc64_runlatch_off();
+ *in_purr = mfspr(SPRN_PURR);
+ /*
+ * Indicate to the HV that we are idle. Now would be
+ * a good time to find other work to dispatch.
+ */
+ get_lppaca()->idle = 1;
+}
+
+static inline void pseries_idle_epilog(unsigned long in_purr)
+{
+ u64 wait_cycles;
+
+ wait_cycles = be64_to_cpu(get_lppaca()->wait_state_cycles);
+ wait_cycles += mfspr(SPRN_PURR) - in_purr;
+ get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
+ get_lppaca()->idle = 0;
+
+ ppc64_runlatch_on();
+}
+#endif
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 0c8421d..2f53e6b 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -68,6 +68,7 @@
#include <asm/isa-bridge.h>
#include <asm/security_features.h>
#include <asm/asm-const.h>
+#include <asm/idle.h>
#include <asm/swiotlb.h>
#include <asm/svm.h>
@@ -319,6 +320,8 @@ static int alloc_dispatch_log_kmem_cache(void)
static void pseries_lpar_idle(void)
{
+ unsigned long in_purr;
+
/*
* Default handler to go into low thread priority and possibly
* low power mode by ceding processor to hypervisor
@@ -328,7 +331,7 @@ static void pseries_lpar_idle(void)
return;
/* Indicate to hypervisor that we are idle. */
- get_lppaca()->idle = 1;
+ pseries_idle_prolog(&in_purr);
/*
* Yield the processor to the hypervisor. We return if
@@ -339,7 +342,7 @@ static void pseries_lpar_idle(void)
*/
cede_processor();
- get_lppaca()->idle = 0;
+ pseries_idle_epilog(in_purr);
}
/*
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
index 74c2479..46d5e05 100644
--- a/drivers/cpuidle/cpuidle-pseries.c
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -19,6 +19,7 @@
#include <asm/machdep.h>
#include <asm/firmware.h>
#include <asm/runlatch.h>
+#include <asm/idle.h>
#include <asm/plpar_wrappers.h>
struct cpuidle_driver pseries_idle_driver = {
@@ -31,29 +32,6 @@ struct cpuidle_driver pseries_idle_driver = {
static u64 snooze_timeout __read_mostly;
static bool snooze_timeout_en __read_mostly;
-static inline void idle_loop_prolog(unsigned long *in_purr)
-{
- ppc64_runlatch_off();
- *in_purr = mfspr(SPRN_PURR);
- /*
- * Indicate to the HV that we are idle. Now would be
- * a good time to find other work to dispatch.
- */
- get_lppaca()->idle = 1;
-}
-
-static inline void idle_loop_epilog(unsigned long in_purr)
-{
- u64 wait_cycles;
-
- wait_cycles = be64_to_cpu(get_lppaca()->wait_state_cycles);
- wait_cycles += mfspr(SPRN_PURR) - in_purr;
- get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
- get_lppaca()->idle = 0;
-
- ppc64_runlatch_on();
-}
-
static int snooze_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
@@ -63,7 +41,7 @@ static int snooze_loop(struct cpuidle_device *dev,
set_thread_flag(TIF_POLLING_NRFLAG);
- idle_loop_prolog(&in_purr);
+ pseries_idle_prolog(&in_purr);
local_irq_enable();
snooze_exit_time = get_tb() + snooze_timeout;
@@ -87,7 +65,7 @@ static int snooze_loop(struct cpuidle_device *dev,
local_irq_disable();
- idle_loop_epilog(in_purr);
+ pseries_idle_epilog(in_purr);
return index;
}
@@ -115,7 +93,7 @@ static int dedicated_cede_loop(struct cpuidle_device *dev,
{
unsigned long in_purr;
- idle_loop_prolog(&in_purr);
+ pseries_idle_prolog(&in_purr);
get_lppaca()->donate_dedicated_cpu = 1;
HMT_medium();
@@ -124,7 +102,7 @@ static int dedicated_cede_loop(struct cpuidle_device *dev,
local_irq_disable();
get_lppaca()->donate_dedicated_cpu = 0;
- idle_loop_epilog(in_purr);
+ pseries_idle_epilog(in_purr);
return index;
}
@@ -135,7 +113,7 @@ static int shared_cede_loop(struct cpuidle_device *dev,
{
unsigned long in_purr;
- idle_loop_prolog(&in_purr);
+ pseries_idle_prolog(&in_purr);
/*
* Yield the processor to the hypervisor. We return if
@@ -147,7 +125,7 @@ static int shared_cede_loop(struct cpuidle_device *dev,
check_and_cede_processor();
local_irq_disable();
- idle_loop_epilog(in_purr);
+ pseries_idle_epilog(in_purr);
return index;
}
--
1.9.4
^ permalink raw reply related
* [PATCH v3 5/6] Documentation: Document sysfs interfaces purr, spurr, idle_purr, idle_spurr
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
In-Reply-To: <1583919461-27405-1-git-send-email-ego@linux.vnet.ibm.com>
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
Add documentation for the following sysfs interfaces:
/sys/devices/system/cpu/cpuX/purr
/sys/devices/system/cpu/cpuX/spurr
/sys/devices/system/cpu/cpuX/idle_purr
/sys/devices/system/cpu/cpuX/idle_spurr
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
Documentation/ABI/testing/sysfs-devices-system-cpu | 39 ++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 2e0e3b4..bc07677 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -580,3 +580,42 @@ Description: Secure Virtual Machine
If 1, it means the system is using the Protected Execution
Facility in POWER9 and newer processors. i.e., it is a Secure
Virtual Machine.
+
+What: /sys/devices/system/cpu/cpuX/purr
+Date: Apr 2005
+Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Description: PURR ticks for this CPU since the system boot.
+
+ The Processor Utilization Resources Register (PURR) is
+ a 64-bit counter which provides an estimate of the
+ resources used by the CPU thread. The contents of this
+ register increases monotonically. This sysfs interface
+ exposes the number of PURR ticks for cpuX.
+
+What: /sys/devices/system/cpu/cpuX/spurr
+Date: Dec 2006
+Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Description: SPURR ticks for this CPU since the system boot.
+
+ The Scaled Processor Utilization Resources Register
+ (SPURR) is a 64-bit counter that provides a frequency
+ invariant estimate of the resources used by the CPU
+ thread. The contents of this register increases
+ monotonically. This sysfs interface exposes the number
+ of SPURR ticks for cpuX.
+
+What: /sys/devices/system/cpu/cpuX/idle_purr
+Date: Mar 2020
+Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Description: PURR ticks for cpuX when it was idle.
+
+ This sysfs interface exposes the number of PURR ticks
+ for cpuX when it was idle.
+
+What: /sys/devices/system/cpu/cpuX/idle_spurr
+Date: Mar 2020
+Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
+Description: SPURR ticks for cpuX when it was idle.
+
+ This sysfs interface exposes the number of SPURR ticks
+ for cpuX when it was idle.
--
1.9.4
^ permalink raw reply related
* [PATCH v3 3/6] powerpc/pseries: Account for SPURR ticks on idle CPUs
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
In-Reply-To: <1583919461-27405-1-git-send-email-ego@linux.vnet.ibm.com>
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
On Pseries LPARs, to calculate utilization, we need to know the
[S]PURR ticks when the CPUs were busy or idle.
Via pseries_idle_prolog(), pseries_idle_epilog(), we track the idle
PURR ticks in the VPA variable "wait_state_cycles". This patch extends
the support to account for the idle SPURR ticks. It also provides an
accessor function to accurately reads idle SPURR ticks.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/idle.h | 33 +++++++++++++++++++++++++++++++++
arch/powerpc/platforms/pseries/setup.c | 2 ++
2 files changed, 35 insertions(+)
diff --git a/arch/powerpc/include/asm/idle.h b/arch/powerpc/include/asm/idle.h
index 7552823..a375589 100644
--- a/arch/powerpc/include/asm/idle.h
+++ b/arch/powerpc/include/asm/idle.h
@@ -3,13 +3,20 @@
#define _ASM_POWERPC_IDLE_H
#include <asm/runlatch.h>
+DECLARE_PER_CPU(u64, idle_spurr_cycles);
DECLARE_PER_CPU(u64, idle_entry_purr_snap);
+DECLARE_PER_CPU(u64, idle_entry_spurr_snap);
static inline void snapshot_purr_idle_entry(void)
{
*this_cpu_ptr(&idle_entry_purr_snap) = mfspr(SPRN_PURR);
}
+static inline void snapshot_spurr_idle_entry(void)
+{
+ *this_cpu_ptr(&idle_entry_spurr_snap) = mfspr(SPRN_SPURR);
+}
+
static inline void update_idle_purr_accounting(void)
{
u64 wait_cycles;
@@ -20,10 +27,19 @@ static inline void update_idle_purr_accounting(void)
get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
}
+static inline void update_idle_spurr_accounting(void)
+{
+ u64 *idle_spurr_cycles_ptr = this_cpu_ptr(&idle_spurr_cycles);
+ u64 in_spurr = *this_cpu_ptr(&idle_entry_spurr_snap);
+
+ *idle_spurr_cycles_ptr += mfspr(SPRN_SPURR) - in_spurr;
+}
+
static inline void pseries_idle_prolog(void)
{
ppc64_runlatch_off();
snapshot_purr_idle_entry();
+ snapshot_spurr_idle_entry();
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
@@ -34,6 +50,7 @@ static inline void pseries_idle_prolog(void)
static inline void pseries_idle_epilog(void)
{
update_idle_purr_accounting();
+ update_idle_spurr_accounting();
get_lppaca()->idle = 0;
ppc64_runlatch_on();
}
@@ -53,4 +70,20 @@ static inline u64 read_this_idle_purr(void)
return be64_to_cpu(get_lppaca()->wait_state_cycles);
}
+
+static inline u64 read_this_idle_spurr(void)
+{
+ /*
+ * If we are reading from an idle context, update the
+ * idle-spurr cycles corresponding to the last idle period.
+ * Since the idle context is not yet over, take a fresh
+ * snapshot of the idle-spurr.
+ */
+ if (get_lppaca()->idle == 1) {
+ update_idle_spurr_accounting();
+ snapshot_spurr_idle_entry();
+ }
+
+ return *this_cpu_ptr(&idle_spurr_cycles);
+}
#endif
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 4905c96..1b55e80 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -318,7 +318,9 @@ static int alloc_dispatch_log_kmem_cache(void)
}
machine_early_initcall(pseries, alloc_dispatch_log_kmem_cache);
+DEFINE_PER_CPU(u64, idle_spurr_cycles);
DEFINE_PER_CPU(u64, idle_entry_purr_snap);
+DEFINE_PER_CPU(u64, idle_entry_spurr_snap);
static void pseries_lpar_idle(void)
{
/*
--
1.9.4
^ permalink raw reply related
* [PATCH v3 2/6] powerpc/idle: Add accessor function to always read latest idle PURR
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
In-Reply-To: <1583919461-27405-1-git-send-email-ego@linux.vnet.ibm.com>
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
Currently when CPU goes idle, we take a snapshot of PURR via
pseries_idle_prolog() which is used at the CPU idle exit to compute
the idle PURR cycles via the function pseries_idle_epilog(). Thus,
the value of idle PURR cycle thus read before pseries_idle_prolog() and
after pseries_idle_epilog() is always correct.
However, if we were to read the idle PURR cycles from an interrupt
context between pseries_idle_prolog() and pseries_idle_epilog() (this will
be done in a future patch), then, the value of the idle PURR thus read
will not include the cycles spent in the most recent idle period.
This patch addresses the issue by providing accessor function to read
the idle PURR such such that it includes the cycles spent in the most
recent idle period, if we read it between pseries_idle_prolog() and
pseries_idle_epilog(). In order to achieve it, the patch saves the
snapshot of PURR in pseries_idle_prolog() in a per-cpu variable,
instead of on the stack, so that it can be accessed from an interrupt
context.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/idle.h | 46 +++++++++++++++++++++++++++-------
arch/powerpc/platforms/pseries/setup.c | 7 +++---
drivers/cpuidle/cpuidle-pseries.c | 15 +++++------
3 files changed, 46 insertions(+), 22 deletions(-)
diff --git a/arch/powerpc/include/asm/idle.h b/arch/powerpc/include/asm/idle.h
index e838ea5..7552823 100644
--- a/arch/powerpc/include/asm/idle.h
+++ b/arch/powerpc/include/asm/idle.h
@@ -3,10 +3,27 @@
#define _ASM_POWERPC_IDLE_H
#include <asm/runlatch.h>
-static inline void pseries_idle_prolog(unsigned long *in_purr)
+DECLARE_PER_CPU(u64, idle_entry_purr_snap);
+
+static inline void snapshot_purr_idle_entry(void)
+{
+ *this_cpu_ptr(&idle_entry_purr_snap) = mfspr(SPRN_PURR);
+}
+
+static inline void update_idle_purr_accounting(void)
+{
+ u64 wait_cycles;
+ u64 in_purr = *this_cpu_ptr(&idle_entry_purr_snap);
+
+ wait_cycles = be64_to_cpu(get_lppaca()->wait_state_cycles);
+ wait_cycles += mfspr(SPRN_PURR) - in_purr;
+ get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
+}
+
+static inline void pseries_idle_prolog(void)
{
ppc64_runlatch_off();
- *in_purr = mfspr(SPRN_PURR);
+ snapshot_purr_idle_entry();
/*
* Indicate to the HV that we are idle. Now would be
* a good time to find other work to dispatch.
@@ -14,15 +31,26 @@ static inline void pseries_idle_prolog(unsigned long *in_purr)
get_lppaca()->idle = 1;
}
-static inline void pseries_idle_epilog(unsigned long in_purr)
+static inline void pseries_idle_epilog(void)
{
- u64 wait_cycles;
-
- wait_cycles = be64_to_cpu(get_lppaca()->wait_state_cycles);
- wait_cycles += mfspr(SPRN_PURR) - in_purr;
- get_lppaca()->wait_state_cycles = cpu_to_be64(wait_cycles);
+ update_idle_purr_accounting();
get_lppaca()->idle = 0;
-
ppc64_runlatch_on();
}
+
+static inline u64 read_this_idle_purr(void)
+{
+ /*
+ * If we are reading from an idle context, update the
+ * idle-purr cycles corresponding to the last idle period.
+ * Since the idle context is not yet over, take a fresh
+ * snapshot of the idle-purr.
+ */
+ if (unlikely(get_lppaca()->idle == 1)) {
+ update_idle_purr_accounting();
+ snapshot_purr_idle_entry();
+ }
+
+ return be64_to_cpu(get_lppaca()->wait_state_cycles);
+}
#endif
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 2f53e6b..4905c96 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -318,10 +318,9 @@ static int alloc_dispatch_log_kmem_cache(void)
}
machine_early_initcall(pseries, alloc_dispatch_log_kmem_cache);
+DEFINE_PER_CPU(u64, idle_entry_purr_snap);
static void pseries_lpar_idle(void)
{
- unsigned long in_purr;
-
/*
* Default handler to go into low thread priority and possibly
* low power mode by ceding processor to hypervisor
@@ -331,7 +330,7 @@ static void pseries_lpar_idle(void)
return;
/* Indicate to hypervisor that we are idle. */
- pseries_idle_prolog(&in_purr);
+ pseries_idle_prolog();
/*
* Yield the processor to the hypervisor. We return if
@@ -342,7 +341,7 @@ static void pseries_lpar_idle(void)
*/
cede_processor();
- pseries_idle_epilog(in_purr);
+ pseries_idle_epilog();
}
/*
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
index 46d5e05..6513ef2 100644
--- a/drivers/cpuidle/cpuidle-pseries.c
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -36,12 +36,11 @@ static int snooze_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
- unsigned long in_purr;
u64 snooze_exit_time;
set_thread_flag(TIF_POLLING_NRFLAG);
- pseries_idle_prolog(&in_purr);
+ pseries_idle_prolog();
local_irq_enable();
snooze_exit_time = get_tb() + snooze_timeout;
@@ -65,7 +64,7 @@ static int snooze_loop(struct cpuidle_device *dev,
local_irq_disable();
- pseries_idle_epilog(in_purr);
+ pseries_idle_epilog();
return index;
}
@@ -91,9 +90,8 @@ static int dedicated_cede_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
- unsigned long in_purr;
- pseries_idle_prolog(&in_purr);
+ pseries_idle_prolog();
get_lppaca()->donate_dedicated_cpu = 1;
HMT_medium();
@@ -102,7 +100,7 @@ static int dedicated_cede_loop(struct cpuidle_device *dev,
local_irq_disable();
get_lppaca()->donate_dedicated_cpu = 0;
- pseries_idle_epilog(in_purr);
+ pseries_idle_epilog();
return index;
}
@@ -111,9 +109,8 @@ static int shared_cede_loop(struct cpuidle_device *dev,
struct cpuidle_driver *drv,
int index)
{
- unsigned long in_purr;
- pseries_idle_prolog(&in_purr);
+ pseries_idle_prolog();
/*
* Yield the processor to the hypervisor. We return if
@@ -125,7 +122,7 @@ static int shared_cede_loop(struct cpuidle_device *dev,
check_and_cede_processor();
local_irq_disable();
- pseries_idle_epilog(in_purr);
+ pseries_idle_epilog();
return index;
}
--
1.9.4
^ permalink raw reply related
* [PATCH v3 4/6] powerpc/sysfs: Show idle_purr and idle_spurr for every CPU
From: Gautham R. Shenoy @ 2020-03-11 9:37 UTC (permalink / raw)
To: Nathan Lynch, Michael Ellerman, Vaidyanathan Srinivasan,
Kamalesh Babulal, Naveen N. Rao, Tyrel Datwyler
Cc: Gautham R. Shenoy, linuxppc-dev, linux-kernel
In-Reply-To: <1583919461-27405-1-git-send-email-ego@linux.vnet.ibm.com>
From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com>
On Pseries LPARs, to calculate utilization, we need to know the
[S]PURR ticks when the CPUs were busy or idle.
The total PURR and SPURR ticks are already exposed via the per-cpu
sysfs files "purr" and "spurr". This patch adds support for exposing
the idle PURR and SPURR ticks via new per-cpu sysfs files named
"idle_purr" and "idle_spurr".
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
---
arch/powerpc/kernel/sysfs.c | 54 ++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 51 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c
index 479c706..c9ddb83 100644
--- a/arch/powerpc/kernel/sysfs.c
+++ b/arch/powerpc/kernel/sysfs.c
@@ -19,6 +19,7 @@
#include <asm/smp.h>
#include <asm/pmc.h>
#include <asm/firmware.h>
+#include <asm/idle.h>
#include <asm/svm.h>
#include "cacheinfo.h"
@@ -760,6 +761,42 @@ static void create_svm_file(void)
}
#endif /* CONFIG_PPC_SVM */
+static void read_idle_purr(void *val)
+{
+ u64 *ret = val;
+
+ *ret = read_this_idle_purr();
+}
+
+static ssize_t idle_purr_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, dev);
+ u64 val;
+
+ smp_call_function_single(cpu->dev.id, read_idle_purr, &val, 1);
+ return sprintf(buf, "%llx\n", val);
+}
+static DEVICE_ATTR(idle_purr, 0400, idle_purr_show, NULL);
+
+static void read_idle_spurr(void *val)
+{
+ u64 *ret = val;
+
+ *ret = read_this_idle_spurr();
+}
+
+static ssize_t idle_spurr_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct cpu *cpu = container_of(dev, struct cpu, dev);
+ u64 val;
+
+ smp_call_function_single(cpu->dev.id, read_idle_spurr, &val, 1);
+ return sprintf(buf, "%llx\n", val);
+}
+static DEVICE_ATTR(idle_spurr, 0400, idle_spurr_show, NULL);
+
static int register_cpu_online(unsigned int cpu)
{
struct cpu *c = &per_cpu(cpu_devices, cpu);
@@ -823,10 +860,15 @@ static int register_cpu_online(unsigned int cpu)
if (!firmware_has_feature(FW_FEATURE_LPAR))
add_write_permission_dev_attr(&dev_attr_purr);
device_create_file(s, &dev_attr_purr);
+ if (firmware_has_feature(FW_FEATURE_LPAR))
+ device_create_file(s, &dev_attr_idle_purr);
}
- if (cpu_has_feature(CPU_FTR_SPURR))
+ if (cpu_has_feature(CPU_FTR_SPURR)) {
device_create_file(s, &dev_attr_spurr);
+ if (firmware_has_feature(FW_FEATURE_LPAR))
+ device_create_file(s, &dev_attr_idle_spurr);
+ }
if (cpu_has_feature(CPU_FTR_DSCR))
device_create_file(s, &dev_attr_dscr);
@@ -910,11 +952,17 @@ static int unregister_cpu_online(unsigned int cpu)
device_remove_file(s, &dev_attr_mmcra);
#endif /* CONFIG_PMU_SYSFS */
- if (cpu_has_feature(CPU_FTR_PURR))
+ if (cpu_has_feature(CPU_FTR_PURR)) {
device_remove_file(s, &dev_attr_purr);
+ if (firmware_has_feature(FW_FEATURE_LPAR))
+ device_remove_file(s, &dev_attr_idle_purr);
+ }
- if (cpu_has_feature(CPU_FTR_SPURR))
+ if (cpu_has_feature(CPU_FTR_SPURR)) {
device_remove_file(s, &dev_attr_spurr);
+ if (firmware_has_feature(FW_FEATURE_LPAR))
+ device_remove_file(s, &dev_attr_idle_spurr);
+ }
if (cpu_has_feature(CPU_FTR_DSCR))
device_remove_file(s, &dev_attr_dscr);
--
1.9.4
^ permalink raw reply related
* [PATCH V16] mm/debug: Add tests validating architecture page table helpers
From: Anshuman Khandual @ 2020-03-11 9:34 UTC (permalink / raw)
To: linux-mm
Cc: Heiko Carstens, Paul Mackerras, H. Peter Anvin, linux-riscv,
Will Deacon, linux-arch, linux-s390, x86, Mike Rapoport,
Christian Borntraeger, Ingo Molnar, Catalin Marinas,
linux-snps-arc, Vasily Gorbik, Anshuman Khandual, Borislav Petkov,
Paul Walmsley, Kirill A . Shutemov, Thomas Gleixner,
linux-arm-kernel, Vineet Gupta, linux-kernel, Palmer Dabbelt,
Qian Cai, Andrew Morton, linuxppc-dev
This adds tests which will validate architecture page table helpers and
other accessors in their compliance with expected generic MM semantics.
This will help various architectures in validating changes to existing
page table helpers or addition of new ones.
This test covers basic page table entry transformations including but not
limited to old, young, dirty, clean, write, write protect etc at various
level along with populating intermediate entries with next page table page
and validating them.
Test page table pages are allocated from system memory with required size
and alignments. The mapped pfns at page table levels are derived from a
real pfn representing a valid kernel text symbol. This test gets called
inside kernel_init() right after async_synchronize_full().
This test gets built and run when CONFIG_DEBUG_VM_PGTABLE is selected. Any
architecture, which is willing to subscribe this test will need to select
ARCH_HAS_DEBUG_VM_PGTABLE. For now this is limited to arc, arm64, x86, s390
and powerpc platforms where the test is known to build and run successfully
Going forward, other architectures too can subscribe the test after fixing
any build or runtime problems with their page table helpers. Meanwhile for
better platform coverage, the test can also be enabled with CONFIG_EXPERT
even without ARCH_HAS_DEBUG_VM_PGTABLE.
Folks interested in making sure that a given platform's page table helpers
conform to expected generic MM semantics should enable the above config
which will just trigger this test during boot. Any non conformity here will
be reported as an warning which would need to be fixed. This test will help
catch any changes to the agreed upon semantics expected from generic MM and
enable platforms to accommodate it thereafter.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-s390@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Cc: x86@kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> # s390
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> # ppc32
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
This adds a test validation for architecture exported page table helpers.
Patch adds basic transformation tests at various levels of the page table.
This test was originally suggested by Catalin during arm64 THP migration
RFC discussion earlier. Going forward it can include more specific tests
with respect to various generic MM functions like THP, HugeTLB etc and
platform specific tests.
https://lore.kernel.org/linux-mm/20190628102003.GA56463@arrakis.emea.arm.com/
Needs to be applied on linux V5.6-rc5
Changes in V16:
- Replaced WRITE_ONCE() with set_pte_at() with a new barrier() in pte_clear_tests() per Qian
- Enabled all powerpc platforms and updated the feature list
Changes in V15: (https://patchwork.kernel.org/patch/11422803/)
- Replaced __pa() with __pa_symbol() (https://patchwork.kernel.org/patch/11407715/)
- Replaced pte_alloc_map() with pte_alloc_map_lock() per Qian
- Replaced pte_unmap() with pte_unmap_unlock() per Qian
- Added address to pte_clear_tests() and passed it down till pte_clear() per Qian
Changes in V14: (https://patchwork.kernel.org/project/linux-mm/list/?series=242305)
- Disabled DEBUG_VM_PGTABLE for IA64 and ARM (32 Bit) per Andrew and Christophe
- Updated DEBUG_VM_PGTABLE documentation wrt EXPERT and disabled platforms
- Updated RANDOM_[OR|NZ]VALUE open encodings with GENMASK() per Catalin
- Updated s390 constraint bits from 12 to 4 (S390_MASK_BITS) per Gerald
- Updated in-code documentation for RANDOM_ORVALUE per Gerald
- Updated pxx_basic_tests() to use invert functions first per Catalin
- Dropped ARCH_HAS_4LEVEL_HACK check from pud_basic_tests()
- Replaced __ARCH_HAS_[4|5]LEVEL_HACK with __PAGETABLE_[PUD|P4D]_FOLDED per Catalin
- Trimmed the CC list on the commit message per Catalin
Changes in V13: (https://patchwork.kernel.org/project/linux-mm/list/?series=237125)
- Subscribed s390 platform and updated debug-vm-pgtable/arch-support.txt per Gerald
- Dropped keyword 'extern' from debug_vm_pgtable() declaration per Christophe
- Moved debug_vm_pgtable() declarations to <linux/mmdebug.h> per Christophe
- Moved debug_vm_pgtable() call site into kernel_init() per Christophe
- Changed CONFIG_DEBUG_VM_PGTABLE rules per Christophe
- Updated commit to include new supported platforms and changed config selection
Changes in V12: (https://patchwork.kernel.org/project/linux-mm/list/?series=233905)
- Replaced __mmdrop() with mmdrop()
- Enable ARCH_HAS_DEBUG_VM_PGTABLE on X86 for non CONFIG_X86_PAE platforms as the
test procedure interfere with pre-allocated PMDs attached to the PGD resulting
in runtime failures with VM_BUG_ON()
Changes in V11: (https://patchwork.kernel.org/project/linux-mm/list/?series=221135)
- Rebased the patch on V5.4
Changes in V10: (https://patchwork.kernel.org/project/linux-mm/list/?series=205529)
- Always enable DEBUG_VM_PGTABLE when DEBUG_VM is enabled per Ingo
- Added tags from Ingo
Changes in V9: (https://patchwork.kernel.org/project/linux-mm/list/?series=201429)
- Changed feature support enumeration for powerpc platforms per Christophe
- Changed config wrapper for basic_[pmd|pud]_tests() to enable ARC platform
- Enabled the test on ARC platform
Changes in V8: (https://patchwork.kernel.org/project/linux-mm/list/?series=194297)
- Enabled ARCH_HAS_DEBUG_VM_PGTABLE on PPC32 platform per Christophe
- Updated feature documentation as DEBUG_VM_PGTABLE is now enabled on PPC32 platform
- Moved ARCH_HAS_DEBUG_VM_PGTABLE earlier to indent it with DEBUG_VM per Christophe
- Added an information message in debug_vm_pgtable() per Christophe
- Dropped random_vaddr boundary condition checks per Christophe and Qian
- Replaced virt_addr_valid() check with pfn_valid() check in debug_vm_pgtable()
- Slightly changed pr_fmt(fmt) information
Changes in V7: (https://patchwork.kernel.org/project/linux-mm/list/?series=193051)
- Memory allocation and free routines for mapped pages have been droped
- Mapped pfns are derived from standard kernel text symbol per Matthew
- Moved debug_vm_pgtaable() after page_alloc_init_late() per Michal and Qian
- Updated the commit message per Michal
- Updated W=1 GCC warning problem on x86 per Qian Cai
- Addition of new alloc_contig_pages() helper has been submitted separately
Changes in V6: (https://patchwork.kernel.org/project/linux-mm/list/?series=187589)
- Moved alloc_gigantic_page_order() into mm/page_alloc.c per Michal
- Moved alloc_gigantic_page_order() within CONFIG_CONTIG_ALLOC in the test
- Folded Andrew's include/asm-generic/pgtable.h fix into the test patch 2/2
Changes in V5: (https://patchwork.kernel.org/project/linux-mm/list/?series=185991)
- Redefined and moved X86 mm_p4d_folded() into a different header per Kirill/Ingo
- Updated the config option comment per Ingo and dropped 'kernel module' reference
- Updated the commit message and dropped 'kernel module' reference
- Changed DEBUG_ARCH_PGTABLE_TEST into DEBUG_VM_PGTABLE per Ingo
- Moved config option from mm/Kconfig.debug into lib/Kconfig.debug
- Renamed core test function arch_pgtable_tests() as debug_vm_pgtable()
- Renamed mm/arch_pgtable_test.c as mm/debug_vm_pgtable.c
- debug_vm_pgtable() gets called from kernel_init_freeable() after init_mm_internals()
- Added an entry in Documentation/features/debug/ per Ingo
- Enabled the test on arm64 and x86 platforms for now
Changes in V4: (https://patchwork.kernel.org/project/linux-mm/list/?series=183465)
- Disable DEBUG_ARCH_PGTABLE_TEST for ARM and IA64 platforms
Changes in V3: (https://lore.kernel.org/patchwork/project/lkml/list/?series=411216)
- Changed test trigger from module format into late_initcall()
- Marked all functions with __init to be freed after completion
- Changed all __PGTABLE_PXX_FOLDED checks as mm_pxx_folded()
- Folded in PPC32 fixes from Christophe
Changes in V2:
https://lore.kernel.org/linux-mm/1568268173-31302-1-git-send-email-anshuman.khandual@arm.com/T/#t
- Fixed small typo error in MODULE_DESCRIPTION()
- Fixed m64k build problems for lvalue concerns in pmd_xxx_tests()
- Fixed dynamic page table level folding problems on x86 as per Kirril
- Fixed second pointers during pxx_populate_tests() per Kirill and Gerald
- Allocate and free pte table with pte_alloc_one/pte_free per Kirill
- Modified pxx_clear_tests() to accommodate s390 lower 12 bits situation
- Changed RANDOM_NZVALUE value from 0xbe to 0xff
- Changed allocation, usage, free sequence for saved_ptep
- Renamed VMA_FLAGS as VMFLAGS
- Implemented a new method for random vaddr generation
- Implemented some other cleanups
- Dropped extern reference to mm_alloc()
- Created and exported new alloc_gigantic_page_order()
- Dropped the custom allocator and used new alloc_gigantic_page_order()
Changes in V1:
https://lore.kernel.org/linux-mm/1567497706-8649-1-git-send-email-anshuman.khandual@arm.com/
- Added fallback mechanism for PMD aligned memory allocation failure
Changes in RFC V2:
https://lore.kernel.org/linux-mm/1565335998-22553-1-git-send-email-anshuman.khandual@arm.com/T/#u
- Moved test module and it's config from lib/ to mm/
- Renamed config TEST_ARCH_PGTABLE as DEBUG_ARCH_PGTABLE_TEST
- Renamed file from test_arch_pgtable.c to arch_pgtable_test.c
- Added relevant MODULE_DESCRIPTION() and MODULE_AUTHOR() details
- Dropped loadable module config option
- Basic tests now use memory blocks with required size and alignment
- PUD aligned memory block gets allocated with alloc_contig_range()
- If PUD aligned memory could not be allocated it falls back on PMD aligned
memory block from page allocator and pud_* tests are skipped
- Clear and populate tests now operate on real in memory page table entries
- Dummy mm_struct gets allocated with mm_alloc()
- Dummy page table entries get allocated with [pud|pmd|pte]_alloc_[map]()
- Simplified [p4d|pgd]_basic_tests(), now has random values in the entries
Original RFC V1:
https://lore.kernel.org/linux-mm/1564037723-26676-1-git-send-email-anshuman.khandual@arm.com/
.../debug/debug-vm-pgtable/arch-support.txt | 34 ++
arch/arc/Kconfig | 1 +
arch/arm64/Kconfig | 1 +
arch/powerpc/Kconfig | 1 +
arch/s390/Kconfig | 1 +
arch/x86/Kconfig | 1 +
arch/x86/include/asm/pgtable_64.h | 6 +
include/linux/mmdebug.h | 5 +
init/main.c | 2 +
lib/Kconfig.debug | 26 ++
mm/Makefile | 1 +
mm/debug_vm_pgtable.c | 392 ++++++++++++++++++
12 files changed, 471 insertions(+)
create mode 100644 Documentation/features/debug/debug-vm-pgtable/arch-support.txt
create mode 100644 mm/debug_vm_pgtable.c
diff --git a/Documentation/features/debug/debug-vm-pgtable/arch-support.txt b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt
new file mode 100644
index 000000000000..c527d05c0459
--- /dev/null
+++ b/Documentation/features/debug/debug-vm-pgtable/arch-support.txt
@@ -0,0 +1,34 @@
+#
+# Feature name: debug-vm-pgtable
+# Kconfig: ARCH_HAS_DEBUG_VM_PGTABLE
+# description: arch supports pgtable tests for semantics compliance
+#
+ -----------------------
+ | arch |status|
+ -----------------------
+ | alpha: | TODO |
+ | arc: | ok |
+ | arm: | TODO |
+ | arm64: | ok |
+ | c6x: | TODO |
+ | csky: | TODO |
+ | h8300: | TODO |
+ | hexagon: | TODO |
+ | ia64: | TODO |
+ | m68k: | TODO |
+ | microblaze: | TODO |
+ | mips: | TODO |
+ | nds32: | TODO |
+ | nios2: | TODO |
+ | openrisc: | TODO |
+ | parisc: | TODO |
+ | powerpc: | ok |
+ | riscv: | TODO |
+ | s390: | ok |
+ | sh: | TODO |
+ | sparc: | TODO |
+ | um: | TODO |
+ | unicore32: | TODO |
+ | x86: | ok |
+ | xtensa: | TODO |
+ -----------------------
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index ff2a393b635c..3e72e6cf0e42 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -6,6 +6,7 @@
config ARC
def_bool y
select ARC_TIMERS
+ select ARCH_HAS_DEBUG_VM_PGTABLE
select ARCH_HAS_DMA_PREP_COHERENT
select ARCH_HAS_PTE_SPECIAL
select ARCH_HAS_SETUP_DMA_OPS
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 0b30e884e088..aaf8ba415145 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -11,6 +11,7 @@ config ARM64
select ACPI_PPTT if ACPI
select ARCH_CLOCKSOURCE_DATA
select ARCH_HAS_DEBUG_VIRTUAL
+ select ARCH_HAS_DEBUG_VM_PGTABLE
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_DMA_PREP_COHERENT
select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 497b7d0b2d7e..072c5302029b 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -116,6 +116,7 @@ config PPC
#
select ARCH_32BIT_OFF_T if PPC32
select ARCH_HAS_DEBUG_VIRTUAL
+ select ARCH_HAS_DEBUG_VM_PGTABLE
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FORTIFY_SOURCE
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 8abe77536d9d..af284dbb07e7 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -59,6 +59,7 @@ config KASAN_SHADOW_OFFSET
config S390
def_bool y
select ARCH_BINFMT_ELF_STATE
+ select ARCH_HAS_DEBUG_VM_PGTABLE
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FORTIFY_SOURCE
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index beea77046f9b..df8a19e52e82 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -61,6 +61,7 @@ config X86
select ARCH_CLOCKSOURCE_INIT
select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
select ARCH_HAS_DEBUG_VIRTUAL
+ select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_FAST_MULTIPLIER
diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 0b6c4042942a..fb0e76d254b3 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -53,6 +53,12 @@ static inline void sync_initial_page_table(void) { }
struct mm_struct;
+#define mm_p4d_folded mm_p4d_folded
+static inline bool mm_p4d_folded(struct mm_struct *mm)
+{
+ return !pgtable_l5_enabled();
+}
+
void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte);
void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte);
diff --git a/include/linux/mmdebug.h b/include/linux/mmdebug.h
index 2ad72d2c8cc5..5339aa14b749 100644
--- a/include/linux/mmdebug.h
+++ b/include/linux/mmdebug.h
@@ -64,4 +64,9 @@ void dump_mm(const struct mm_struct *mm);
#define VM_BUG_ON_PGFLAGS(cond, page) BUILD_BUG_ON_INVALID(cond)
#endif
+#ifdef CONFIG_DEBUG_VM_PGTABLE
+void debug_vm_pgtable(void);
+#else
+static inline void debug_vm_pgtable(void) { }
+#endif
#endif
diff --git a/init/main.c b/init/main.c
index ee4947af823f..19cd7900bb0c 100644
--- a/init/main.c
+++ b/init/main.c
@@ -94,6 +94,7 @@
#include <linux/rodata_test.h>
#include <linux/jump_label.h>
#include <linux/mem_encrypt.h>
+#include <linux/mmdebug.h>
#include <asm/io.h>
#include <asm/bugs.h>
@@ -1352,6 +1353,7 @@ static int __ref kernel_init(void *unused)
kernel_init_freeable();
/* need to finish all async __init code before freeing the memory */
async_synchronize_full();
+ debug_vm_pgtable();
ftrace_free_init_mem();
free_initmem();
mark_readonly();
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 69def4a9df00..1b5bd9f7c967 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -653,6 +653,12 @@ config SCHED_STACK_END_CHECK
data corruption or a sporadic crash at a later stage once the region
is examined. The runtime overhead introduced is minimal.
+config ARCH_HAS_DEBUG_VM_PGTABLE
+ bool
+ help
+ An architecture should select this when it can successfully
+ build and run DEBUG_VM_PGTABLE.
+
config DEBUG_VM
bool "Debug VM"
depends on DEBUG_KERNEL
@@ -688,6 +694,26 @@ config DEBUG_VM_PGFLAGS
If unsure, say N.
+config DEBUG_VM_PGTABLE
+ bool "Debug arch page table for semantics compliance"
+ depends on MMU
+ depends on !IA64 && !ARM
+ depends on ARCH_HAS_DEBUG_VM_PGTABLE || EXPERT
+ default n if !ARCH_HAS_DEBUG_VM_PGTABLE
+ default y if DEBUG_VM
+ help
+ This option provides a debug method which can be used to test
+ architecture page table helper functions on various platforms in
+ verifying if they comply with expected generic MM semantics. This
+ will help architecture code in making sure that any changes or
+ new additions of these helpers still conform to expected
+ semantics of the generic MM. Platforms will have to opt in for
+ this through ARCH_HAS_DEBUG_VM_PGTABLE. Although it can also be
+ enabled through EXPERT without requiring code change. This test
+ is disabled on IA64 and ARM platforms where it fails to build.
+
+ If unsure, say N.
+
config ARCH_HAS_DEBUG_VIRTUAL
bool
diff --git a/mm/Makefile b/mm/Makefile
index 272e66039e70..b0692e6a4b58 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -87,6 +87,7 @@ obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o
obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
obj-$(CONFIG_DEBUG_RODATA_TEST) += rodata_test.o
+obj-$(CONFIG_DEBUG_VM_PGTABLE) += debug_vm_pgtable.o
obj-$(CONFIG_PAGE_OWNER) += page_owner.o
obj-$(CONFIG_CLEANCACHE) += cleancache.o
obj-$(CONFIG_MEMORY_ISOLATION) += page_isolation.o
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
new file mode 100644
index 000000000000..98990a515268
--- /dev/null
+++ b/mm/debug_vm_pgtable.c
@@ -0,0 +1,392 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This kernel test validates architecture page table helpers and
+ * accessors and helps in verifying their continued compliance with
+ * expected generic MM semantics.
+ *
+ * Copyright (C) 2019 ARM Ltd.
+ *
+ * Author: Anshuman Khandual <anshuman.khandual@arm.com>
+ */
+#define pr_fmt(fmt) "debug_vm_pgtable: %s: " fmt, __func__
+
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/hugetlb.h>
+#include <linux/kernel.h>
+#include <linux/kconfig.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/mm_types.h>
+#include <linux/module.h>
+#include <linux/pfn_t.h>
+#include <linux/printk.h>
+#include <linux/random.h>
+#include <linux/spinlock.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <linux/start_kernel.h>
+#include <linux/sched/mm.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+
+/*
+ * Basic operations
+ *
+ * mkold(entry) = An old and not a young entry
+ * mkyoung(entry) = A young and not an old entry
+ * mkdirty(entry) = A dirty and not a clean entry
+ * mkclean(entry) = A clean and not a dirty entry
+ * mkwrite(entry) = A write and not a write protected entry
+ * wrprotect(entry) = A write protected and not a write entry
+ * pxx_bad(entry) = A mapped and non-table entry
+ * pxx_same(entry1, entry2) = Both entries hold the exact same value
+ */
+#define VMFLAGS (VM_READ|VM_WRITE|VM_EXEC)
+
+/*
+ * On s390 platform, the lower 4 bits are used to identify given page table
+ * entry type. But these bits might affect the ability to clear entries with
+ * pxx_clear() because of how dynamic page table folding works on s390. So
+ * while loading up the entries do not change the lower 4 bits. It does not
+ * have affect any other platform.
+ */
+#define S390_MASK_BITS 4
+#define RANDOM_ORVALUE GENMASK(BITS_PER_LONG - 1, S390_MASK_BITS)
+#define RANDOM_NZVALUE GENMASK(7, 0)
+
+static void __init pte_basic_tests(unsigned long pfn, pgprot_t prot)
+{
+ pte_t pte = pfn_pte(pfn, prot);
+
+ WARN_ON(!pte_same(pte, pte));
+ WARN_ON(!pte_young(pte_mkyoung(pte_mkold(pte))));
+ WARN_ON(!pte_dirty(pte_mkdirty(pte_mkclean(pte))));
+ WARN_ON(!pte_write(pte_mkwrite(pte_wrprotect(pte))));
+ WARN_ON(pte_young(pte_mkold(pte_mkyoung(pte))));
+ WARN_ON(pte_dirty(pte_mkclean(pte_mkdirty(pte))));
+ WARN_ON(pte_write(pte_wrprotect(pte_mkwrite(pte))));
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot)
+{
+ pmd_t pmd = pfn_pmd(pfn, prot);
+
+ WARN_ON(!pmd_same(pmd, pmd));
+ WARN_ON(!pmd_young(pmd_mkyoung(pmd_mkold(pmd))));
+ WARN_ON(!pmd_dirty(pmd_mkdirty(pmd_mkclean(pmd))));
+ WARN_ON(!pmd_write(pmd_mkwrite(pmd_wrprotect(pmd))));
+ WARN_ON(pmd_young(pmd_mkold(pmd_mkyoung(pmd))));
+ WARN_ON(pmd_dirty(pmd_mkclean(pmd_mkdirty(pmd))));
+ WARN_ON(pmd_write(pmd_wrprotect(pmd_mkwrite(pmd))));
+ /*
+ * A huge page does not point to next level page table
+ * entry. Hence this must qualify as pmd_bad().
+ */
+ WARN_ON(!pmd_bad(pmd_mkhuge(pmd)));
+}
+
+#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
+static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot)
+{
+ pud_t pud = pfn_pud(pfn, prot);
+
+ WARN_ON(!pud_same(pud, pud));
+ WARN_ON(!pud_young(pud_mkyoung(pud_mkold(pud))));
+ WARN_ON(!pud_write(pud_mkwrite(pud_wrprotect(pud))));
+ WARN_ON(pud_write(pud_wrprotect(pud_mkwrite(pud))));
+ WARN_ON(pud_young(pud_mkold(pud_mkyoung(pud))));
+
+ if (mm_pmd_folded(mm))
+ return;
+
+ /*
+ * A huge page does not point to next level page table
+ * entry. Hence this must qualify as pud_bad().
+ */
+ WARN_ON(!pud_bad(pud_mkhuge(pud)));
+}
+#else
+static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) { }
+#endif
+#else
+static void __init pmd_basic_tests(unsigned long pfn, pgprot_t prot) { }
+static void __init pud_basic_tests(unsigned long pfn, pgprot_t prot) { }
+#endif
+
+static void __init p4d_basic_tests(unsigned long pfn, pgprot_t prot)
+{
+ p4d_t p4d;
+
+ memset(&p4d, RANDOM_NZVALUE, sizeof(p4d_t));
+ WARN_ON(!p4d_same(p4d, p4d));
+}
+
+static void __init pgd_basic_tests(unsigned long pfn, pgprot_t prot)
+{
+ pgd_t pgd;
+
+ memset(&pgd, RANDOM_NZVALUE, sizeof(pgd_t));
+ WARN_ON(!pgd_same(pgd, pgd));
+}
+
+#ifndef __PAGETABLE_PUD_FOLDED
+static void __init pud_clear_tests(struct mm_struct *mm, pud_t *pudp)
+{
+ pud_t pud = READ_ONCE(*pudp);
+
+ if (mm_pmd_folded(mm))
+ return;
+
+ pud = __pud(pud_val(pud) | RANDOM_ORVALUE);
+ WRITE_ONCE(*pudp, pud);
+ pud_clear(pudp);
+ pud = READ_ONCE(*pudp);
+ WARN_ON(!pud_none(pud));
+}
+
+static void __init pud_populate_tests(struct mm_struct *mm, pud_t *pudp,
+ pmd_t *pmdp)
+{
+ pud_t pud;
+
+ if (mm_pmd_folded(mm))
+ return;
+ /*
+ * This entry points to next level page table page.
+ * Hence this must not qualify as pud_bad().
+ */
+ pmd_clear(pmdp);
+ pud_clear(pudp);
+ pud_populate(mm, pudp, pmdp);
+ pud = READ_ONCE(*pudp);
+ WARN_ON(pud_bad(pud));
+}
+#else
+static void __init pud_clear_tests(struct mm_struct *mm, pud_t *pudp) { }
+static void __init pud_populate_tests(struct mm_struct *mm, pud_t *pudp,
+ pmd_t *pmdp)
+{
+}
+#endif
+
+#ifndef __PAGETABLE_P4D_FOLDED
+static void __init p4d_clear_tests(struct mm_struct *mm, p4d_t *p4dp)
+{
+ p4d_t p4d = READ_ONCE(*p4dp);
+
+ if (mm_pud_folded(mm))
+ return;
+
+ p4d = __p4d(p4d_val(p4d) | RANDOM_ORVALUE);
+ WRITE_ONCE(*p4dp, p4d);
+ p4d_clear(p4dp);
+ p4d = READ_ONCE(*p4dp);
+ WARN_ON(!p4d_none(p4d));
+}
+
+static void __init p4d_populate_tests(struct mm_struct *mm, p4d_t *p4dp,
+ pud_t *pudp)
+{
+ p4d_t p4d;
+
+ if (mm_pud_folded(mm))
+ return;
+
+ /*
+ * This entry points to next level page table page.
+ * Hence this must not qualify as p4d_bad().
+ */
+ pud_clear(pudp);
+ p4d_clear(p4dp);
+ p4d_populate(mm, p4dp, pudp);
+ p4d = READ_ONCE(*p4dp);
+ WARN_ON(p4d_bad(p4d));
+}
+
+static void __init pgd_clear_tests(struct mm_struct *mm, pgd_t *pgdp)
+{
+ pgd_t pgd = READ_ONCE(*pgdp);
+
+ if (mm_p4d_folded(mm))
+ return;
+
+ pgd = __pgd(pgd_val(pgd) | RANDOM_ORVALUE);
+ WRITE_ONCE(*pgdp, pgd);
+ pgd_clear(pgdp);
+ pgd = READ_ONCE(*pgdp);
+ WARN_ON(!pgd_none(pgd));
+}
+
+static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
+ p4d_t *p4dp)
+{
+ pgd_t pgd;
+
+ if (mm_p4d_folded(mm))
+ return;
+
+ /*
+ * This entry points to next level page table page.
+ * Hence this must not qualify as pgd_bad().
+ */
+ p4d_clear(p4dp);
+ pgd_clear(pgdp);
+ pgd_populate(mm, pgdp, p4dp);
+ pgd = READ_ONCE(*pgdp);
+ WARN_ON(pgd_bad(pgd));
+}
+#else
+static void __init p4d_clear_tests(struct mm_struct *mm, p4d_t *p4dp) { }
+static void __init pgd_clear_tests(struct mm_struct *mm, pgd_t *pgdp) { }
+static void __init p4d_populate_tests(struct mm_struct *mm, p4d_t *p4dp,
+ pud_t *pudp)
+{
+}
+static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
+ p4d_t *p4dp)
+{
+}
+#endif
+
+static void __init pte_clear_tests(struct mm_struct *mm, pte_t *ptep,
+ unsigned long vaddr)
+{
+ pte_t pte = READ_ONCE(*ptep);
+
+ pte = __pte(pte_val(pte) | RANDOM_ORVALUE);
+ set_pte_at(mm, vaddr, ptep, pte);
+ barrier();
+ pte_clear(mm, vaddr, ptep);
+ pte = READ_ONCE(*ptep);
+ WARN_ON(!pte_none(pte));
+}
+
+static void __init pmd_clear_tests(struct mm_struct *mm, pmd_t *pmdp)
+{
+ pmd_t pmd = READ_ONCE(*pmdp);
+
+ pmd = __pmd(pmd_val(pmd) | RANDOM_ORVALUE);
+ WRITE_ONCE(*pmdp, pmd);
+ pmd_clear(pmdp);
+ pmd = READ_ONCE(*pmdp);
+ WARN_ON(!pmd_none(pmd));
+}
+
+static void __init pmd_populate_tests(struct mm_struct *mm, pmd_t *pmdp,
+ pgtable_t pgtable)
+{
+ pmd_t pmd;
+
+ /*
+ * This entry points to next level page table page.
+ * Hence this must not qualify as pmd_bad().
+ */
+ pmd_clear(pmdp);
+ pmd_populate(mm, pmdp, pgtable);
+ pmd = READ_ONCE(*pmdp);
+ WARN_ON(pmd_bad(pmd));
+}
+
+static unsigned long __init get_random_vaddr(void)
+{
+ unsigned long random_vaddr, random_pages, total_user_pages;
+
+ total_user_pages = (TASK_SIZE - FIRST_USER_ADDRESS) / PAGE_SIZE;
+
+ random_pages = get_random_long() % total_user_pages;
+ random_vaddr = FIRST_USER_ADDRESS + random_pages * PAGE_SIZE;
+
+ return random_vaddr;
+}
+
+void __init debug_vm_pgtable(void)
+{
+ struct mm_struct *mm;
+ pgd_t *pgdp;
+ p4d_t *p4dp, *saved_p4dp;
+ pud_t *pudp, *saved_pudp;
+ pmd_t *pmdp, *saved_pmdp, pmd;
+ pte_t *ptep;
+ pgtable_t saved_ptep;
+ pgprot_t prot;
+ phys_addr_t paddr;
+ unsigned long vaddr, pte_aligned, pmd_aligned;
+ unsigned long pud_aligned, p4d_aligned, pgd_aligned;
+ spinlock_t *uninitialized_var(ptl);
+
+ pr_info("Validating architecture page table helpers\n");
+ prot = vm_get_page_prot(VMFLAGS);
+ vaddr = get_random_vaddr();
+ mm = mm_alloc();
+ if (!mm) {
+ pr_err("mm_struct allocation failed\n");
+ return;
+ }
+
+ /*
+ * PFN for mapping at PTE level is determined from a standard kernel
+ * text symbol. But pfns for higher page table levels are derived by
+ * masking lower bits of this real pfn. These derived pfns might not
+ * exist on the platform but that does not really matter as pfn_pxx()
+ * helpers will still create appropriate entries for the test. This
+ * helps avoid large memory block allocations to be used for mapping
+ * at higher page table levels.
+ */
+ paddr = __pa_symbol(&start_kernel);
+
+ pte_aligned = (paddr & PAGE_MASK) >> PAGE_SHIFT;
+ pmd_aligned = (paddr & PMD_MASK) >> PAGE_SHIFT;
+ pud_aligned = (paddr & PUD_MASK) >> PAGE_SHIFT;
+ p4d_aligned = (paddr & P4D_MASK) >> PAGE_SHIFT;
+ pgd_aligned = (paddr & PGDIR_MASK) >> PAGE_SHIFT;
+ WARN_ON(!pfn_valid(pte_aligned));
+
+ pgdp = pgd_offset(mm, vaddr);
+ p4dp = p4d_alloc(mm, pgdp, vaddr);
+ pudp = pud_alloc(mm, p4dp, vaddr);
+ pmdp = pmd_alloc(mm, pudp, vaddr);
+ ptep = pte_alloc_map_lock(mm, pmdp, vaddr, &ptl);
+
+ /*
+ * Save all the page table page addresses as the page table
+ * entries will be used for testing with random or garbage
+ * values. These saved addresses will be used for freeing
+ * page table pages.
+ */
+ pmd = READ_ONCE(*pmdp);
+ saved_p4dp = p4d_offset(pgdp, 0UL);
+ saved_pudp = pud_offset(p4dp, 0UL);
+ saved_pmdp = pmd_offset(pudp, 0UL);
+ saved_ptep = pmd_pgtable(pmd);
+
+ pte_basic_tests(pte_aligned, prot);
+ pmd_basic_tests(pmd_aligned, prot);
+ pud_basic_tests(pud_aligned, prot);
+ p4d_basic_tests(p4d_aligned, prot);
+ pgd_basic_tests(pgd_aligned, prot);
+
+ pte_clear_tests(mm, ptep, vaddr);
+ pmd_clear_tests(mm, pmdp);
+ pud_clear_tests(mm, pudp);
+ p4d_clear_tests(mm, p4dp);
+ pgd_clear_tests(mm, pgdp);
+
+ pte_unmap_unlock(ptep, ptl);
+
+ pmd_populate_tests(mm, pmdp, saved_ptep);
+ pud_populate_tests(mm, pudp, saved_pmdp);
+ p4d_populate_tests(mm, p4dp, saved_pudp);
+ pgd_populate_tests(mm, pgdp, saved_p4dp);
+
+ p4d_free(mm, saved_p4dp);
+ pud_free(mm, saved_pudp);
+ pmd_free(mm, saved_pmdp);
+ pte_free(mm, saved_ptep);
+
+ mm_dec_nr_puds(mm);
+ mm_dec_nr_pmds(mm);
+ mm_dec_nr_ptes(mm);
+ mmdrop(mm);
+}
--
2.20.1
^ permalink raw reply related
* Re: [PATCH -next 017/491] CELL BROADBAND ENGINE ARCHITECTURE: Use fallthrough;
From: Arnd Bergmann @ 2020-03-11 8:08 UTC (permalink / raw)
To: Joe Perches
Cc: linux-kernel@vger.kernel.org, Paul Mackerras, Jeremy Kerr,
linuxppc-dev
In-Reply-To: <03073a9a269010ca439e9e658629c44602b0cc9f.1583896348.git.joe@perches.com>
On Wed, Mar 11, 2020 at 6:07 AM Joe Perches <joe@perches.com> wrote:
>
> Convert the various uses of fallthrough comments to fallthrough;
>
> Done via script
> Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe.com/
>
> Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
^ permalink raw reply
* [PATCH] hwmon: (ibmpowernv) Use scnprintf() for avoiding potential buffer overflow
From: Takashi Iwai @ 2020-03-11 7:39 UTC (permalink / raw)
To: Jean Delvare, Guenter Roeck, linux-hwmon, linuxppc-dev
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit. Fix it by replacing with scnprintf().
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
drivers/hwmon/ibmpowernv.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/hwmon/ibmpowernv.c b/drivers/hwmon/ibmpowernv.c
index 0e525cfbdfc5..a750647e66a4 100644
--- a/drivers/hwmon/ibmpowernv.c
+++ b/drivers/hwmon/ibmpowernv.c
@@ -186,7 +186,7 @@ static void make_sensor_label(struct device_node *np,
u32 id;
size_t n;
- n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
+ n = scnprintf(sdata->label, sizeof(sdata->label), "%s", label);
/*
* Core temp pretty print
@@ -199,11 +199,11 @@ static void make_sensor_label(struct device_node *np,
* The digital thermal sensors are associated
* with a core.
*/
- n += snprintf(sdata->label + n,
+ n += scnprintf(sdata->label + n,
sizeof(sdata->label) - n, " %d",
cpuid);
else
- n += snprintf(sdata->label + n,
+ n += scnprintf(sdata->label + n,
sizeof(sdata->label) - n, " phy%d", id);
}
@@ -211,7 +211,7 @@ static void make_sensor_label(struct device_node *np,
* Membuffer pretty print
*/
if (!of_property_read_u32(np, "ibm,chip-id", &id))
- n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
+ n += scnprintf(sdata->label + n, sizeof(sdata->label) - n,
" %d", id & 0xffff);
}
--
2.16.4
^ permalink raw reply related
* Re: [PATCH 1/2] powerpc test_emulate_step: fix DS operand in ld encoding to appropriate value
From: Balamuruhan S @ 2020-03-11 7:21 UTC (permalink / raw)
To: Christophe Leroy, mpe
Cc: ravi.bangoria, jniethe5, paulus, sandipan, naveen.n.rao,
linuxppc-dev
In-Reply-To: <188eadfa-6908-196a-ed77-cec210c54c84@c-s.fr>
On Wed, 2020-03-11 at 08:01 +0100, Christophe Leroy wrote:
>
> Le 11/03/2020 à 07:14, Balamuruhan S a écrit :
> > ld instruction should have 14 bit immediate field (DS) concatenated
> > with
> > 0b00 on the right, encode it accordingly.
> >
> > Fixes: 4ceae137bdab ("powerpc: emulate_step() tests for load/store
> > instructions")
> > Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
> > Signed-off-by: Balamuruhan S <bala24@linux.ibm.com>
> > ---
> > arch/powerpc/lib/test_emulate_step.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/lib/test_emulate_step.c
> > b/arch/powerpc/lib/test_emulate_step.c
> > index 42347067739c..51c254fd15b5 100644
> > --- a/arch/powerpc/lib/test_emulate_step.c
> > +++ b/arch/powerpc/lib/test_emulate_step.c
> > @@ -19,7 +19,7 @@
> > * definitions.
> > */
> > #define TEST_LD(r, base, i) (PPC_INST_LD | ___PPC_RT(r) |
> > \
> > - ___PPC_RA(base) | IMM_L(i))
> > + ___PPC_RA(base) | ((i) &
> > 0xfffc))
>
> I think you should squash patch 1 and 2 together. Or at least you
> should
> put the new IMM_DS macro in patch 1 and use it instead of open
> coding.
sure, I will make the changes as suggested.
-- Bala
>
> > #define TEST_LWZ(r, base, i) (PPC_INST_LWZ | ___PPC_RT(r) |
> > \
> > ___PPC_RA(base) | IMM_L(i))
> > #define TEST_LWZX(t, a, b) (PPC_INST_LWZX | ___PPC_RT(t) |
> > \
> >
> > base-commit: 5aa19adac1f3152a5fd3b865a1ab46bb845d3696
> >
>
> Christophe
^ permalink raw reply
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