From mboxrd@z Thu Jan 1 00:00:00 1970 From: Minchan Kim Subject: Re: [PATCH] mm: add gfp_mask parameter to vm_map_ram() Date: Thu, 14 Jun 2012 11:39:36 +0900 Message-ID: <4FD94EE8.9030300@kernel.org> References: <20120612012134.GA7706@localhost> <20120613123932.GA1445@localhost> <20120614012026.GL3019@devil.redhat.com> <20120614014902.GB7289@localhost> <4FD94779.3030108@kernel.org> <20120614022132.GA3766@dhcp-172-17-108-109.mtv.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Fengguang Wu , Dave Chinner , Christoph Hellwig , linux-fsdevel@vger.kernel.org, LKML , Andrew Morton , Linux Memory Management List , xfs@oss.sgi.com To: Tejun Heo Return-path: In-Reply-To: <20120614022132.GA3766@dhcp-172-17-108-109.mtv.corp.google.com> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On 06/14/2012 11:21 AM, Tejun Heo wrote: > Hello, guys. > > On Thu, Jun 14, 2012 at 11:07:53AM +0900, Minchan Kim wrote: >> It shouldn't work because vmap_page_range still can allocate >> GFP_KERNEL by pud_alloc in vmap_pud_range. For it, I tried [1] but >> other mm guys want to add WARNING [2] so let's avoiding gfp context >> passing. >> >> [1] https://lkml.org/lkml/2012/4/23/77 >> [2] https://lkml.org/lkml/2012/5/2/340 > > Yeah, vmalloc area doesn't support !GFP_KERNEL allocations and as > Minchan said, changing this would require updating page table > allocation functions on all archs. This is the same reason why percpu > allocator doesn't support !GFP_KERNEL allocations which in turn made > blk-throttle implement its own private percpu pool. > > If xfs can't live without GFP_NOFS vmalloc allocations, either it has > to implement its own pool or maybe it's time to implement !GFP_KERNEL > allocs for vmalloc area. I don't know. There is another example in ARM. http://www.spinics.net/lists/arm-kernel/msg179202.html They try to make pool for atomic vmalloc support. :( Only GFP_KERNEL support vmalloc spreads out many pools in system, Sigh. -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org