Re: [PATCH v1 5/5] mm/memory_hotplug: print only with DEBUG_VM in online/offline_pages()

From: Wei Yang <richard.weiyang@gmail.com>
To: Oscar Salvador <osalvador@techadventures.net>
Cc: David Hildenbrand <david@redhat.com>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Michal Hocko <mhocko@suse.com>, Vlastimil Babka <vbabka@suse.cz>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Pavel Tatashin <pasha.tatashin@oracle.com>,
	Kemi Wang <kemi.wang@intel.com>,
	David Rientjes <rientjes@google.com>,
	Jia He <jia.he@hxt-semitech.com>,
	Oscar Salvador <osalvador@suse.de>,
	Petr Tesarik <ptesarik@suse.com>,
	Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Mathieu Malaterre <malat@debian.org>, Baoquan He <bhe@redhat.com>,
	Wei Yang <richard.weiyang@gmail.com>,
	Ross Zwisler <zwisler@kernel.org>,
	"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Subject: Re: [PATCH v1 5/5] mm/memory_hotplug: print only with DEBUG_VM in online/offline_pages()
Date: Sun, 19 Aug 2018 20:34:03 +0800	[thread overview]
Message-ID: <20180819123403.GA22352@WeideMacBook-Pro.local> (raw)
In-Reply-To: <20180817081853.GB17638@techadventures.net>

On Fri, Aug 17, 2018 at 10:18:53AM +0200, Oscar Salvador wrote:
>>  failed_addition:
>> +#ifdef CONFIG_DEBUG_VM
>>  	pr_debug("online_pages [mem %#010llx-%#010llx] failed\n",
>>  		 (unsigned long long) pfn << PAGE_SHIFT,
>>  		 (((unsigned long long) pfn + nr_pages) << PAGE_SHIFT) - 1);
>> +#endif
>
>I have never been sure about this.
>IMO, if I fail to online pages, I want to know I failed.
>I think that pr_err would be better than pr_debug and without CONFIG_DEBUG_VM.
>
>But at least, if not, envolve it with a CONFIG_DEBUG_VM, but change pr_debug to pr_info.
>

I don't have a clear rule about these debug macro neither.

While when you look at the page related logs in calculate_node_totalpages(),
it is KERNEL_DEBUG level and without any config macro.

Maybe we should leave them at the same state?

>> +#ifdef CONFIG_DEBUG_VM
>>  	pr_debug("memory offlining [mem %#010llx-%#010llx] failed\n",
>>  		 (unsigned long long) start_pfn << PAGE_SHIFT,
>>  		 ((unsigned long long) end_pfn << PAGE_SHIFT) - 1);
>> +#endif
>
>Same goes here.
>
>Thanks
>-- 
>Oscar Salvador
>SUSE L3

-- 
Wei Yang
Help you, Help me