From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757474AbYDOP2Q (ORCPT ); Tue, 15 Apr 2008 11:28:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751234AbYDOP2A (ORCPT ); Tue, 15 Apr 2008 11:28:00 -0400 Received: from mx1.redhat.com ([66.187.233.31]:33338 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750711AbYDOP2A (ORCPT ); Tue, 15 Apr 2008 11:28:00 -0400 Message-ID: <4804C95F.2080204@redhat.com> Date: Tue, 15 Apr 2008 11:27:27 -0400 From: Masami Hiramatsu User-Agent: Thunderbird 2.0.0.12 (X11/20080226) MIME-Version: 1.0 To: David Wilder , Tom Zanussi , Andrew Morton CC: systemtap-ml , LKML Subject: [PATCH -mm] relayfs: support larger relay buffer X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use vmalloc() and memset() instead of kcalloc() to allocate a page* array when the array size is bigger than one page. This enables relayfs to support bigger relay buffers than 64MB on 4k-page system, 512MB on 16k-page system. Signed-off-by: Masami Hiramatsu --- This is useful for a 64-bit system which has a plenty of memory (tens of giga bytes) and a large kernel memory space. I tested it on x86-64 and ia64. kernel/relay.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) Index: 2.6.25-rc8-mm2/kernel/relay.c =================================================================== --- 2.6.25-rc8-mm2.orig/kernel/relay.c +++ 2.6.25-rc8-mm2/kernel/relay.c @@ -104,12 +104,20 @@ static int relay_mmap_buf(struct rchan_b static void *relay_alloc_buf(struct rchan_buf *buf, size_t *size) { void *mem; - unsigned int i, j, n_pages; + unsigned int i, j, n_pages, pa_size; *size = PAGE_ALIGN(*size); n_pages = *size >> PAGE_SHIFT; + pa_size = n_pages * sizeof(struct page *); - buf->page_array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL); + if (pa_size > PAGE_SIZE) { + buf->page_array = vmalloc(pa_size); + if (buf->page_array) + memset(buf->page_array, 0, pa_size); + } else { + buf->page_array = kcalloc(n_pages, sizeof(struct page *), + GFP_KERNEL); + } if (!buf->page_array) return NULL; @@ -130,7 +138,10 @@ static void *relay_alloc_buf(struct rcha depopulate: for (j = 0; j < i; j++) __free_page(buf->page_array[j]); - kfree(buf->page_array); + if (pa_size > PAGE_SIZE) + vfree(buf->page_array); + else + kfree(buf->page_array); return NULL; } @@ -189,7 +200,10 @@ static void relay_destroy_buf(struct rch vunmap(buf->start); for (i = 0; i < buf->page_count; i++) __free_page(buf->page_array[i]); - kfree(buf->page_array); + if (buf->page_count * sizeof(struct page *) > PAGE_SIZE) + vfree(buf->page_array); + else + kfree(buf->page_array); } chan->buf[buf->cpu] = NULL; kfree(buf->padding); -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America) Inc. Software Solutions Division e-mail: mhiramat@redhat.com