Re: [PATCH V2 0/2] OMAPDSS: Enable dynamic debug printing
From: Tomi Valkeinen <hidden>
Date: 2012-09-26 14:29:52
Also in:
linux-omap
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From: Tomi Valkeinen <hidden>
Date: 2012-09-26 14:29:52
Also in:
linux-omap
Hi, On Wed, 2012-09-26 at 10:45 +0530, Chandrabhanu Mahapatra wrote:
Hi everyone, this patch series aims at cleaning up of DSS of printk()'s enabled with dss_debug and replace them with generic dynamic debug printing. The 1st patch * replaces printk() in DSSDBG definition with pr_debug() * removes DSSDBGF definition and replaces its instances with DSSDBG() The 2nd patch * cleans up printk()'s in omap_dispc_unregister_isr() and _dsi_print_reset_status() with pr_debug() * removes dss_debug variable Changes with respect to V1: * added debug messages to DSSDBG calls replacing DSSDBGF * added patch "OMAPDSS: Remove dss_debug variable" All your comments and suggestions are welcome.
This doesn't work quite correctly. The problem is in dss.h, where we define DEBUG if CONFIG_OMAP2_DSS_DEBUG_SUPPORT is set. The thing is, DEBUG should be defined before including the kernel headers where the pr_debug etc are defined. So if you try the patches without dynamic debugging enabled, you won't get any debug outputs at all, even if CONFIG_OMAP2_DSS_DEBUG_SUPPORT is set. And for dynamic debug, the Kconfig help says: If a source file is compiled with DEBUG flag set, any pr_debug() calls in it are enabled by default, but can be disabled at runtime as below. Note that DEBUG flag is turned on by many CONFIG_*DEBUG* options. So if we have CONFIG_OMAP2_DSS_DEBUG_SUPPORT set, all the pr_debugs should be enabled by default, which is not the case, again because DEBUG is defined too late. I think setting DEBUG in dss.h should be removed, and instead DEBUG should be set in the makefile if CONFIG_OMAP2_DSS_DEBUG_SUPPORT is set. Tomi