Re: [PATCH v1 4/5] mm/memory_hotplug: convert memhp_auto_online to store an online_type

From: Wei Yang
Date: Wed Mar 11 2020 - 10:25:06 EST


On Wed, Mar 11, 2020 at 01:30:25PM +0100, David Hildenbrand wrote:
>... and rename it to memhp_default_online_type. This is a preparation
>for more detailed default online behavior.
>
>Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>Cc: Michal Hocko <mhocko@xxxxxxxxxx>
>Cc: Oscar Salvador <osalvador@xxxxxxx>
>Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
>Cc: Baoquan He <bhe@xxxxxxxxxx>
>Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
>Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
>Cc: Paul Mackerras <paulus@xxxxxxxxx>
>Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
>Cc: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx>
>Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
>Cc: Stephen Hemminger <sthemmin@xxxxxxxxxxxxx>
>Cc: Wei Liu <wei.liu@xxxxxxxxxx>
>Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
>Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
>Cc: linux-hyperv@xxxxxxxxxxxxxxx
>Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>

Reviewed-by: Wei Yang <richard.weiyang@xxxxxxxxx>

>---
> 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

--
Wei Yang
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