From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3rb7SY5TYTzDq60 for ; Fri, 24 Jun 2016 03:17:33 +1000 (AEST) Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u5NHDhuO145950 for ; Thu, 23 Jun 2016 13:17:31 -0400 Received: from e17.ny.us.ibm.com (e17.ny.us.ibm.com [129.33.205.207]) by mx0a-001b2d01.pphosted.com with ESMTP id 23rkcesj04-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 23 Jun 2016 13:17:31 -0400 Received: from localhost by e17.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 23 Jun 2016 13:17:30 -0400 From: "Aneesh Kumar K.V" To: Reza Arbab , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Dan Williams , Balbir Singh , Gavin Shan , David Gibson , Vasant Hegde , Scott Wood , "Oliver O'Halloran" , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] powerpc/mm: update arch_{add,remove}_memory() for radix In-Reply-To: <1466699962-22412-1-git-send-email-arbab@linux.vnet.ibm.com> References: <1466699962-22412-1-git-send-email-arbab@linux.vnet.ibm.com> Date: Thu, 23 Jun 2016 22:47:20 +0530 MIME-Version: 1.0 Content-Type: text/plain Message-Id: <87mvmbygdb.fsf@skywalker.in.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reza Arbab writes: > These functions are making direct calls to the hash table APIs, > leading to a BUG() on systems using radix. > > Switch them to the vmemmap_{create,remove}_mapping() wrappers, and > move to the __meminit section. They are really not the same. They can possibly end up using different base page size. Also vmemmap is available only with SPARSEMEM_VMEMMAP enabled. Does hotplug depend on sparsemem vmemmap ? > > Signed-off-by: Reza Arbab > --- > arch/powerpc/mm/mem.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c > index 2fd57fa..80c6ee7 100644 > --- a/arch/powerpc/mm/mem.c > +++ b/arch/powerpc/mm/mem.c > @@ -116,7 +116,7 @@ int memory_add_physaddr_to_nid(u64 start) > } > #endif > > -int arch_add_memory(int nid, u64 start, u64 size, bool for_device) > +int __meminit arch_add_memory(int nid, u64 start, u64 size, bool for_device) > { > struct pglist_data *pgdata; > struct zone *zone; > @@ -127,7 +127,7 @@ int arch_add_memory(int nid, u64 start, u64 size, bool for_device) > pgdata = NODE_DATA(nid); > > start = (unsigned long)__va(start); > - rc = create_section_mapping(start, start + size); > + rc = vmemmap_create_mapping(start, size, __pa(start)); > if (rc) { > pr_warning( > "Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n", > @@ -143,7 +143,7 @@ int arch_add_memory(int nid, u64 start, u64 size, bool for_device) > } > > #ifdef CONFIG_MEMORY_HOTREMOVE > -int arch_remove_memory(u64 start, u64 size) > +int __meminit arch_remove_memory(u64 start, u64 size) > { > unsigned long start_pfn = start >> PAGE_SHIFT; > unsigned long nr_pages = size >> PAGE_SHIFT; > @@ -157,7 +157,7 @@ int arch_remove_memory(u64 start, u64 size) > > /* Remove htab bolted mappings for this section of memory */ > start = (unsigned long)__va(start); > - ret = remove_section_mapping(start, start + size); > + vmemmap_remove_mapping(start, size); > > /* Ensure all vmalloc mappings are flushed in case they also > * hit that section of memory > -- > 1.8.3.1 We really want to look at memory hotplug to fully understand the radix impact. The unplug operation needs to do some additional freeing. I did put in comments around that with the idea of coming back to that later #ifdef CONFIG_MEMORY_HOTPLUG void radix__vmemmap_remove_mapping(unsigned long start, unsigned long page_size) { /* FIXME!! intel does more. We should free page tables mapping vmemmap ? */ } #endif -aneesh