From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-6.0 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable autolearn_force=no version=3.4.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 1A3B57D584 for ; Tue, 21 Aug 2018 10:44:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727276AbeHUOEQ (ORCPT ); Tue, 21 Aug 2018 10:04:16 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34198 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727181AbeHUOEP (ORCPT ); Tue, 21 Aug 2018 10:04:15 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AD4F340216F2; Tue, 21 Aug 2018 10:44:35 +0000 (UTC) Received: from t460s.redhat.com (ovpn-117-96.ams2.redhat.com [10.36.117.96]) by smtp.corp.redhat.com (Postfix) with ESMTP id A5C5C94641; Tue, 21 Aug 2018 10:44:31 +0000 (UTC) From: David Hildenbrand To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, xen-devel@lists.xenproject.org, devel@linuxdriverproject.org, David Hildenbrand , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , "Rafael J. Wysocki" , Len Brown , Rashmica Gupta , Michael Neuling , Balbir Singh , Nathan Fontenot , John Allen , Andrew Morton , Michal Hocko , Dan Williams , Joonsoo Kim , Vlastimil Babka , Pavel Tatashin , Greg Kroah-Hartman , Oscar Salvador , YASUAKI ISHIMATSU , Mathieu Malaterre Subject: [PATCH RFCv2 1/6] mm/memory_hotplug: make remove_memory() take the device_hotplug_lock Date: Tue, 21 Aug 2018 12:44:13 +0200 Message-Id: <20180821104418.12710-2-david@redhat.com> In-Reply-To: <20180821104418.12710-1-david@redhat.com> References: <20180821104418.12710-1-david@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.11.54.5 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 21 Aug 2018 10:44:35 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Tue, 21 Aug 2018 10:44:35 +0000 (UTC) for IP:'10.11.54.5' DOMAIN:'int-mx05.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'david@redhat.com' RCPT:'' Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org remove_memory() is exported right now but requires the device_hotplug_lock, which is not exported. So let's provide a variant that takes the lock and only export that one. The lock is already held in arch/powerpc/platforms/pseries/hotplug-memory.c drivers/acpi/acpi_memhotplug.c So, let's use the locked variant. The lock is not held (but taken in) arch/powerpc/platforms/powernv/memtrace.c So let's keep using the (now) locked variant. Apart from that, there are not other users in the tree. Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Rashmica Gupta Cc: Michael Neuling Cc: Balbir Singh Cc: Nathan Fontenot Cc: John Allen Cc: Andrew Morton Cc: Michal Hocko Cc: Dan Williams Cc: Joonsoo Kim Cc: Vlastimil Babka Cc: Pavel Tatashin Cc: Greg Kroah-Hartman Cc: Oscar Salvador Cc: YASUAKI ISHIMATSU Cc: Mathieu Malaterre Signed-off-by: David Hildenbrand --- arch/powerpc/platforms/powernv/memtrace.c | 2 -- arch/powerpc/platforms/pseries/hotplug-memory.c | 6 +++--- drivers/acpi/acpi_memhotplug.c | 2 +- include/linux/memory_hotplug.h | 3 ++- mm/memory_hotplug.c | 9 ++++++++- 5 files changed, 14 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/platforms/powernv/memtrace.c b/arch/powerpc/platforms/powernv/memtrace.c index 51dc398ae3f7..8f1cd4f3bfd5 100644 --- a/arch/powerpc/platforms/powernv/memtrace.c +++ b/arch/powerpc/platforms/powernv/memtrace.c @@ -90,9 +90,7 @@ static bool memtrace_offline_pages(u32 nid, u64 start_pfn, u64 nr_pages) walk_memory_range(start_pfn, end_pfn, (void *)MEM_OFFLINE, change_memblock_state); - lock_device_hotplug(); remove_memory(nid, start_pfn << PAGE_SHIFT, nr_pages << PAGE_SHIFT); - unlock_device_hotplug(); return true; } diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index c1578f54c626..b3f54466e25f 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -334,7 +334,7 @@ static int pseries_remove_memblock(unsigned long base, unsigned int memblock_siz nid = memory_add_physaddr_to_nid(base); for (i = 0; i < sections_per_block; i++) { - remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE); + __remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE); base += MIN_MEMORY_BLOCK_SIZE; } @@ -423,7 +423,7 @@ static int dlpar_remove_lmb(struct drmem_lmb *lmb) block_sz = pseries_memory_block_size(); nid = memory_add_physaddr_to_nid(lmb->base_addr); - remove_memory(nid, lmb->base_addr, block_sz); + __remove_memory(nid, lmb->base_addr, block_sz); /* Update memory regions for memory remove */ memblock_remove(lmb->base_addr, block_sz); @@ -710,7 +710,7 @@ static int dlpar_add_lmb(struct drmem_lmb *lmb) rc = dlpar_online_lmb(lmb); if (rc) { - remove_memory(nid, lmb->base_addr, block_sz); + __remove_memory(nid, lmb->base_addr, block_sz); dlpar_remove_device_tree_lmb(lmb); } else { lmb->flags |= DRCONF_MEM_ASSIGNED; diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c index 6b0d3ef7309c..811148415993 100644 --- a/drivers/acpi/acpi_memhotplug.c +++ b/drivers/acpi/acpi_memhotplug.c @@ -282,7 +282,7 @@ static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device) nid = memory_add_physaddr_to_nid(info->start_addr); acpi_unbind_memory_blocks(info); - remove_memory(nid, info->start_addr, info->length); + __remove_memory(nid, info->start_addr, info->length); list_del(&info->list); kfree(info); } diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 34a28227068d..1f096852f479 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -301,6 +301,7 @@ extern bool is_mem_section_removable(unsigned long pfn, unsigned long nr_pages); extern void try_offline_node(int nid); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages); extern void remove_memory(int nid, u64 start, u64 size); +extern void __remove_memory(int nid, u64 start, u64 size); #else static inline bool is_mem_section_removable(unsigned long pfn, @@ -317,6 +318,7 @@ static inline int offline_pages(unsigned long start_pfn, unsigned long nr_pages) } static inline void remove_memory(int nid, u64 start, u64 size) {} +static inline void __remove_memory(int nid, u64 start, u64 size) {} #endif /* CONFIG_MEMORY_HOTREMOVE */ extern void __ref free_area_init_core_hotplug(int nid); @@ -330,7 +332,6 @@ extern void move_pfn_range_to_zone(struct zone *zone, unsigned long start_pfn, unsigned long nr_pages, struct vmem_altmap *altmap); extern int offline_pages(unsigned long start_pfn, unsigned long nr_pages); extern bool is_memblock_offlined(struct memory_block *mem); -extern void remove_memory(int nid, u64 start, u64 size); extern int sparse_add_one_section(struct pglist_data *pgdat, unsigned long start_pfn, struct vmem_altmap *altmap); extern void sparse_remove_one_section(struct zone *zone, struct mem_section *ms, diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 9eea6e809a4e..898e13d4d87d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1872,7 +1872,7 @@ EXPORT_SYMBOL(try_offline_node); * and online/offline operations before this call, as required by * try_offline_node(). */ -void __ref remove_memory(int nid, u64 start, u64 size) +void __ref __remove_memory(int nid, u64 start, u64 size) { int ret; @@ -1901,5 +1901,12 @@ void __ref remove_memory(int nid, u64 start, u64 size) mem_hotplug_done(); } + +void __ref remove_memory(int nid, u64 start, u64 size) +{ + lock_device_hotplug(); + __remove_memory(nid, start, size); + unlock_device_hotplug(); +} EXPORT_SYMBOL_GPL(remove_memory); #endif /* CONFIG_MEMORY_HOTREMOVE */ -- 2.17.1