From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2BF10CA9EAB for ; Fri, 18 Oct 2019 17:27:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C584222C3 for ; Fri, 18 Oct 2019 17:27:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2634511AbfJRR1n (ORCPT ); Fri, 18 Oct 2019 13:27:43 -0400 Received: from eddie.linux-mips.org ([148.251.95.138]:46700 "EHLO cvs.linux-mips.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2505513AbfJRR1f (ORCPT ); Fri, 18 Oct 2019 13:27:35 -0400 Received: (from localhost user: 'ladis' uid#1021 fake: STDIN (ladis@eddie.linux-mips.org)) by eddie.linux-mips.org id S23993628AbfJRR1bkgOYe (ORCPT + 2 others); Fri, 18 Oct 2019 19:27:31 +0200 Date: Fri, 18 Oct 2019 19:27:28 +0200 From: Ladislav Michl To: Sudip Mukherjee Cc: Bartlomiej Zolnierkiewicz , linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH] omapfb: reduce stack usage Message-ID: <20191018172728.GA11857@lenoch> References: <20191018163004.23498-1-sudipm.mukherjee@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191018163004.23498-1-sudipm.mukherjee@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 18, 2019 at 05:30:04PM +0100, Sudip Mukherjee wrote: > The build of xtensa allmodconfig is giving a warning of: > In function 'dsi_dump_dsidev_irqs': > warning: the frame size of 1120 bytes is larger than 1024 bytes > > Allocate the memory for 'struct dsi_irq_stats' dynamically instead > of assigning it in stack. So now function can fail silently, executes longer, code is sligthly bigger... And all that to silent warning about exceeding frame size. Is it really worth "fixing"? > Signed-off-by: Sudip Mukherjee > --- > drivers/video/fbdev/omap2/omapfb/dss/dsi.c | 24 ++++++++++++++---------- > 1 file changed, 14 insertions(+), 10 deletions(-) > > diff --git a/drivers/video/fbdev/omap2/omapfb/dss/dsi.c b/drivers/video/fbdev/omap2/omapfb/dss/dsi.c > index d620376216e1..43402467bf40 100644 > --- a/drivers/video/fbdev/omap2/omapfb/dss/dsi.c > +++ b/drivers/video/fbdev/omap2/omapfb/dss/dsi.c > @@ -1536,22 +1536,25 @@ static void dsi_dump_dsidev_irqs(struct platform_device *dsidev, > { > struct dsi_data *dsi = dsi_get_dsidrv_data(dsidev); > unsigned long flags; > - struct dsi_irq_stats stats; > + struct dsi_irq_stats *stats; > > + stats = kmalloc(sizeof(*stats), GFP_KERNEL); > + if (!stats) > + return; > spin_lock_irqsave(&dsi->irq_stats_lock, flags); > > - stats = dsi->irq_stats; > + memcpy(stats, &dsi->irq_stats, sizeof(*stats)); > memset(&dsi->irq_stats, 0, sizeof(dsi->irq_stats)); > dsi->irq_stats.last_reset = jiffies; > > spin_unlock_irqrestore(&dsi->irq_stats_lock, flags); > > seq_printf(s, "period %u ms\n", > - jiffies_to_msecs(jiffies - stats.last_reset)); > + jiffies_to_msecs(jiffies - stats->last_reset)); > > - seq_printf(s, "irqs %d\n", stats.irq_count); > + seq_printf(s, "irqs %d\n", stats->irq_count); > #define PIS(x) \ > - seq_printf(s, "%-20s %10d\n", #x, stats.dsi_irqs[ffs(DSI_IRQ_##x)-1]); > + seq_printf(s, "%-20s %10d\n", #x, stats->dsi_irqs[ffs(DSI_IRQ_##x)-1]); > > seq_printf(s, "-- DSI%d interrupts --\n", dsi->module_id + 1); > PIS(VC0); > @@ -1575,10 +1578,10 @@ static void dsi_dump_dsidev_irqs(struct platform_device *dsidev, > > #define PIS(x) \ > seq_printf(s, "%-20s %10d %10d %10d %10d\n", #x, \ > - stats.vc_irqs[0][ffs(DSI_VC_IRQ_##x)-1], \ > - stats.vc_irqs[1][ffs(DSI_VC_IRQ_##x)-1], \ > - stats.vc_irqs[2][ffs(DSI_VC_IRQ_##x)-1], \ > - stats.vc_irqs[3][ffs(DSI_VC_IRQ_##x)-1]); > + stats->vc_irqs[0][ffs(DSI_VC_IRQ_##x)-1], \ > + stats->vc_irqs[1][ffs(DSI_VC_IRQ_##x)-1], \ > + stats->vc_irqs[2][ffs(DSI_VC_IRQ_##x)-1], \ > + stats->vc_irqs[3][ffs(DSI_VC_IRQ_##x)-1]); > > seq_printf(s, "-- VC interrupts --\n"); > PIS(CS); > @@ -1594,7 +1597,7 @@ static void dsi_dump_dsidev_irqs(struct platform_device *dsidev, > > #define PIS(x) \ > seq_printf(s, "%-20s %10d\n", #x, \ > - stats.cio_irqs[ffs(DSI_CIO_IRQ_##x)-1]); > + stats->cio_irqs[ffs(DSI_CIO_IRQ_##x)-1]); > > seq_printf(s, "-- CIO interrupts --\n"); > PIS(ERRSYNCESC1); > @@ -1618,6 +1621,7 @@ static void dsi_dump_dsidev_irqs(struct platform_device *dsidev, > PIS(ULPSACTIVENOT_ALL0); > PIS(ULPSACTIVENOT_ALL1); > #undef PIS > + kfree(stats); > } > > static void dsi1_dump_irqs(struct seq_file *s) > -- > 2.11.0