From patchwork Mon Feb 8 23:30:33 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Randy Dunlap X-Patchwork-Id: 2653 Return-path: Envelope-to: mchehab@infradead.org Delivery-date: Mon, 08 Feb 2010 23:32:36 +0000 Received: from bombadil.infradead.org [18.85.46.34] by pedra with IMAP (fetchmail-6.3.6) for (single-drop); Mon, 08 Feb 2010 21:35:30 -0200 (BRST) Received: from vger.kernel.org ([209.132.180.67]) by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) id 1Ned5o-0000ea-6d; Mon, 08 Feb 2010 23:32:36 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752567Ab0BHXcf (ORCPT + 1 other); Mon, 8 Feb 2010 18:32:35 -0500 Received: from rcsinet12.oracle.com ([148.87.113.124]:52458 "EHLO rcsinet12.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750780Ab0BHXce (ORCPT ); Mon, 8 Feb 2010 18:32:34 -0500 Received: from acsinet15.oracle.com (acsinet15.oracle.com [141.146.126.227]) by rcsinet12.oracle.com (Switch-3.4.2/Switch-3.4.2) with ESMTP id o18NVjHo007674 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 8 Feb 2010 23:31:46 GMT Received: from acsmt354.oracle.com (acsmt354.oracle.com [141.146.40.154]) by acsinet15.oracle.com (Switch-3.4.2/Switch-3.4.1) with ESMTP id o180fxxf010387; Mon, 8 Feb 2010 23:31:44 GMT Received: from abhmt016.oracle.com by acsmt355.oracle.com with ESMTP id 18678081265671837; Mon, 08 Feb 2010 15:30:37 -0800 Received: from chimera.site (/141.144.64.1) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 08 Feb 2010 15:30:37 -0800 Message-ID: <4B709E99.8050405@oracle.com> Date: Mon, 08 Feb 2010 15:30:33 -0800 From: Randy Dunlap Organization: Oracle Linux Engineering User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091209 Fedora/3.0-3.fc11 Thunderbird/3.0 MIME-Version: 1.0 To: linux-media@vger.kernel.org, Mauro Carvalho Chehab , Andrew Morton CC: Patrick Boettcher Subject: [PATCH] dib3000mc: reduce large stack usage X-Source-IP: acsmt354.oracle.com [141.146.40.154] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090209.4B709EE1.0065:SCFMA4539814,ss=1,fgs=0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Randy Dunlap This patch reduces static stack usage of one of the 2 top offenders as listed by 'make checkstack': Building with CONFIG_FRAME_WARN=2048 produces: drivers/media/dvb/frontends/dib3000mc.c:853: warning: the frame size of 2224 bytes is larger than 2048 bytes and in 'make checkstack', the stack usage goes from: 0x00000bbd dib3000mc_i2c_enumeration [dib3000mc]: 2232 to unlisted with this patch. I don't have the hardware that is needed to test this patch. Signed-off-by: Randy Dunlap Cc: Patrick Boettcher --- drivers/media/dvb/frontends/dib3000mc.c | 35 +++++++++++++--------- 1 file changed, 22 insertions(+), 13 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- lnx-2633-rc7.orig/drivers/media/dvb/frontends/dib3000mc.c +++ lnx-2633-rc7/drivers/media/dvb/frontends/dib3000mc.c @@ -813,42 +813,51 @@ EXPORT_SYMBOL(dib3000mc_set_config); int dib3000mc_i2c_enumeration(struct i2c_adapter *i2c, int no_of_demods, u8 default_addr, struct dib3000mc_config cfg[]) { - struct dib3000mc_state st = { .i2c_adap = i2c }; + struct dib3000mc_state *dmcst; int k; u8 new_addr; static u8 DIB3000MC_I2C_ADDRESS[] = {20,22,24,26}; + dmcst = kzalloc(sizeof(struct dib3000mc_state), GFP_KERNEL); + if (dmcst == NULL) + return -ENODEV; + + dmcst->i2c_adap = i2c; + for (k = no_of_demods-1; k >= 0; k--) { - st.cfg = &cfg[k]; + dmcst->cfg = &cfg[k]; /* designated i2c address */ new_addr = DIB3000MC_I2C_ADDRESS[k]; - st.i2c_addr = new_addr; - if (dib3000mc_identify(&st) != 0) { - st.i2c_addr = default_addr; - if (dib3000mc_identify(&st) != 0) { + dmcst->i2c_addr = new_addr; + if (dib3000mc_identify(dmcst) != 0) { + dmcst->i2c_addr = default_addr; + if (dib3000mc_identify(dmcst) != 0) { dprintk("-E- DiB3000P/MC #%d: not identified\n", k); + kfree(dmcst); return -ENODEV; } } - dib3000mc_set_output_mode(&st, OUTMODE_MPEG2_PAR_CONT_CLK); + dib3000mc_set_output_mode(dmcst, OUTMODE_MPEG2_PAR_CONT_CLK); // set new i2c address and force divstr (Bit 1) to value 0 (Bit 0) - dib3000mc_write_word(&st, 1024, (new_addr << 3) | 0x1); - st.i2c_addr = new_addr; + dib3000mc_write_word(dmcst, 1024, (new_addr << 3) | 0x1); + dmcst->i2c_addr = new_addr; } for (k = 0; k < no_of_demods; k++) { - st.cfg = &cfg[k]; - st.i2c_addr = DIB3000MC_I2C_ADDRESS[k]; + dmcst->cfg = &cfg[k]; + dmcst->i2c_addr = DIB3000MC_I2C_ADDRESS[k]; - dib3000mc_write_word(&st, 1024, st.i2c_addr << 3); + dib3000mc_write_word(dmcst, 1024, dmcst->i2c_addr << 3); /* turn off data output */ - dib3000mc_set_output_mode(&st, OUTMODE_HIGH_Z); + dib3000mc_set_output_mode(dmcst, OUTMODE_HIGH_Z); } + + kfree(dmcst); return 0; } EXPORT_SYMBOL(dib3000mc_i2c_enumeration);