From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Yang Date: Tue, 04 Jun 2019 22:07:15 +0000 Subject: Re: [PATCH v3 09/11] mm/memory_hotplug: Remove memory block devices before arch_remove_memory() Message-Id: <20190604220715.d4d2ctwjk25vd5sq@master> List-Id: References: <20190527111152.16324-1-david@redhat.com> <20190527111152.16324-10-david@redhat.com> In-Reply-To: <20190527111152.16324-10-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: David Hildenbrand Cc: Michal Hocko , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Wei Yang , linux-mm@kvack.org, Arun KS , Ingo Molnar , linux-s390@vger.kernel.org, "Rafael J. Wysocki" , Pavel Tatashin , "mike.travis@hpe.com" , Mark Brown , Jonathan Cameron , Dan Williams , Chris Wilson , linux-arm-kernel@lists.infradead.org, Oscar Salvador , Andrew Banman , Mathieu Malaterre , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Alex Deucher , Igor Mammedov , akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org, "David S. Miller" On Mon, May 27, 2019 at 01:11:50PM +0200, David Hildenbrand wrote: >Let's factor out removing of memory block devices, which is only >necessary for memory added via add_memory() and friends that created >memory block devices. Remove the devices before calling >arch_remove_memory(). > >This finishes factoring out memory block device handling from >arch_add_memory() and arch_remove_memory(). > >Cc: Greg Kroah-Hartman >Cc: "Rafael J. Wysocki" >Cc: David Hildenbrand >Cc: "mike.travis@hpe.com" >Cc: Andrew Morton >Cc: Andrew Banman >Cc: Ingo Molnar >Cc: Alex Deucher >Cc: "David S. Miller" >Cc: Mark Brown >Cc: Chris Wilson >Cc: Oscar Salvador >Cc: Jonathan Cameron >Cc: Michal Hocko >Cc: Pavel Tatashin >Cc: Arun KS >Cc: Mathieu Malaterre >Reviewed-by: Dan Williams >Signed-off-by: David Hildenbrand >--- > drivers/base/memory.c | 37 ++++++++++++++++++------------------- > drivers/base/node.c | 11 ++++++----- > include/linux/memory.h | 2 +- > include/linux/node.h | 6 ++---- > mm/memory_hotplug.c | 5 +++-- > 5 files changed, 30 insertions(+), 31 deletions(-) > >diff --git a/drivers/base/memory.c b/drivers/base/memory.c >index 5a0370f0c506..f28efb0bf5c7 100644 >--- a/drivers/base/memory.c >+++ b/drivers/base/memory.c >@@ -763,32 +763,31 @@ int create_memory_block_devices(unsigned long start, unsigned long size) > return ret; > } > >-void unregister_memory_section(struct mem_section *section) >+/* >+ * Remove memory block devices for the given memory area. Start and size >+ * have to be aligned to memory block granularity. Memory block devices >+ * have to be offline. >+ */ >+void remove_memory_block_devices(unsigned long start, unsigned long size) > { >+ const int start_block_id = pfn_to_block_id(PFN_DOWN(start)); >+ const int end_block_id = pfn_to_block_id(PFN_DOWN(start + size)); > struct memory_block *mem; >+ int block_id; > >- if (WARN_ON_ONCE(!present_section(section))) >+ if (WARN_ON_ONCE(!IS_ALIGNED(start, memory_block_size_bytes()) || >+ !IS_ALIGNED(size, memory_block_size_bytes()))) > return; > > mutex_lock(&mem_sysfs_mutex); >- >- /* >- * Some users of the memory hotplug do not want/need memblock to >- * track all sections. Skip over those. >- */ >- mem = find_memory_block(section); >- if (!mem) >- goto out_unlock; >- >- unregister_mem_sect_under_nodes(mem, __section_nr(section)); >- >- mem->section_count--; >- if (mem->section_count = 0) >+ for (block_id = start_block_id; block_id != end_block_id; block_id++) { >+ mem = find_memory_block_by_id(block_id, NULL); >+ if (WARN_ON_ONCE(!mem)) >+ continue; >+ mem->section_count = 0; Is this step necessary? >+ unregister_memory_block_under_nodes(mem); > unregister_memory(mem); >- else >- put_device(&mem->dev); >- >-out_unlock: >+ } > mutex_unlock(&mem_sysfs_mutex); > } > >diff --git a/drivers/base/node.c b/drivers/base/node.c >index 8598fcbd2a17..04fdfa99b8bc 100644 >--- a/drivers/base/node.c >+++ b/drivers/base/node.c >@@ -801,9 +801,10 @@ int register_mem_sect_under_node(struct memory_block *mem_blk, void *arg) > return 0; > } > >-/* unregister memory section under all nodes that it spans */ >-int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, >- unsigned long phys_index) >+/* >+ * Unregister memory block device under all nodes that it spans. >+ */ >+int unregister_memory_block_under_nodes(struct memory_block *mem_blk) > { > NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL); > unsigned long pfn, sect_start_pfn, sect_end_pfn; >@@ -816,8 +817,8 @@ int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, > return -ENOMEM; > nodes_clear(*unlinked_nodes); > >- sect_start_pfn = section_nr_to_pfn(phys_index); >- sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1; >+ sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr); >+ sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr); > for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) { > int nid; > >diff --git a/include/linux/memory.h b/include/linux/memory.h >index db3e8567f900..f26a5417ec5d 100644 >--- a/include/linux/memory.h >+++ b/include/linux/memory.h >@@ -112,7 +112,7 @@ extern void unregister_memory_notifier(struct notifier_block *nb); > extern int register_memory_isolate_notifier(struct notifier_block *nb); > extern void unregister_memory_isolate_notifier(struct notifier_block *nb); > int create_memory_block_devices(unsigned long start, unsigned long size); >-extern void unregister_memory_section(struct mem_section *); >+void remove_memory_block_devices(unsigned long start, unsigned long size); > extern int memory_dev_init(void); > extern int memory_notify(unsigned long val, void *v); > extern int memory_isolate_notify(unsigned long val, void *v); >diff --git a/include/linux/node.h b/include/linux/node.h >index 1a557c589ecb..02a29e71b175 100644 >--- a/include/linux/node.h >+++ b/include/linux/node.h >@@ -139,8 +139,7 @@ extern int register_cpu_under_node(unsigned int cpu, unsigned int nid); > extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid); > extern int register_mem_sect_under_node(struct memory_block *mem_blk, > void *arg); >-extern int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, >- unsigned long phys_index); >+extern int unregister_memory_block_under_nodes(struct memory_block *mem_blk); > > extern int register_memory_node_under_compute_node(unsigned int mem_nid, > unsigned int cpu_nid, >@@ -176,8 +175,7 @@ static inline int register_mem_sect_under_node(struct memory_block *mem_blk, > { > return 0; > } >-static inline int unregister_mem_sect_under_nodes(struct memory_block *mem_blk, >- unsigned long phys_index) >+static inline int unregister_memory_block_under_nodes(struct memory_block *mem_blk) > { > return 0; > } >diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >index 9a92549ef23b..82136c5b4c5f 100644 >--- a/mm/memory_hotplug.c >+++ b/mm/memory_hotplug.c >@@ -520,8 +520,6 @@ static void __remove_section(struct zone *zone, struct mem_section *ms, > if (WARN_ON_ONCE(!valid_section(ms))) > return; > >- unregister_memory_section(ms); >- > scn_nr = __section_nr(ms); > start_pfn = section_nr_to_pfn((unsigned long)scn_nr); > __remove_zone(zone, start_pfn); >@@ -1845,6 +1843,9 @@ void __ref __remove_memory(int nid, u64 start, u64 size) > memblock_free(start, size); > memblock_remove(start, size); > >+ /* remove memory block devices before removing memory */ >+ remove_memory_block_devices(start, size); >+ > arch_remove_memory(nid, start, size, NULL); > __release_memory_resource(start, size); > >-- >2.20.1 -- Wei Yang Help you, Help me