From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: vmalloc: Return page array on vunmap Date: Thu, 27 Mar 2008 23:22:20 +1100 References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200803272322.20493.nickpiggin@yahoo.com.au> Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: akpm@linux-foundation.org, linux-mm@kvack.org List-ID: On Thursday 27 March 2008 15:18, Christoph Lameter wrote: > Make vunmap return the page array that was used at vmap. This is useful > if one has no structures to track the page array but simply stores the > virtual address somewhere. The disposition of the page array can then > be decided upon by the caller after vunmap has torn down the mapping. > > vfree() may now also be used instead of vunmap. vfree() will release the > page array after vunmap'ping it. If vfree() is called to free the page > array then the page array must either be > > 1. Allocated via the slab allocator > > 2. Allocated via vmalloc but then VM_VPAGES must have been passed at > vunmap to specify that a vfree is needed. Is this really for something important? Because vmap/vunmap is so slow and unscalable that it is pretty well unusable for any kind of dynamic allocations. I have mostly rewritten it so it is a lot more scalable, but all these little patches will make annoying rejects... Can it wait? -- 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