From 6e1ce52d146fe8197c1b58e2e3b0ebcf9ccda349 Mon Sep 17 00:00:00 2001 From: Michael Brown Date: Tue, 5 Jul 2016 10:19:36 +0100 Subject: [debug] Allow debug messages to be initially disabled at runtime Extend the DEBUG=... syntax to allow debug messages to be compiled in but disabled by default. For example: make bin/undionly.kpxe DEBUG=netdevice:3:1 would compile in the messages as for DEBUG=netdevice:3, but would set the debug level mask so that only the DEBUG=netdevice:1 messages would be displayed. This allows for external code to selectively enable the additional debug messages at runtime, without being overwhelmed by unwanted initial noise. For example, a developer of a new protocol may want to temporarily enable tracing of all packets received: this can be done by building with DEBUG=netdevice:3:1 and using // temporarily enable per-packet messages DBG_ENABLE_OBJECT ( netdevice, DBGLVL_EXTRA ); ... // disable per-packet messages DBG_DISABLE_OBJECT ( netdevice, DBGLVL_EXTRA ); Note that unlike the usual DBG_ENABLE() and DBG_DISABLE() macros, DBG_ENABLE_OBJECT() and DBG_DISABLE_OBJECT() will not be removed via dead code elimination if debugging is disabled in the specified object. In particular, this means that using either of these macros will always result in a symbol reference to the specified object. Signed-off-by: Michael Brown --- src/Makefile.housekeeping | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'src/Makefile.housekeeping') diff --git a/src/Makefile.housekeeping b/src/Makefile.housekeeping index ceff8141..264b9d0f 100644 --- a/src/Makefile.housekeeping +++ b/src/Makefile.housekeeping @@ -523,19 +523,25 @@ POST_O := POST_O_DEPS := endif +# Debug level calculations +# +DBGLVL_MAX = -DDBGLVL_MAX=$(firstword $(subst ., ,$(1))) +DBGLVL_DFLT = -DDBGLVL_DFLT=$(lastword $(subst ., ,$(1))) +DBGLVL = $(call DBGLVL_MAX,$(1)) $(call DBGLVL_DFLT,$(1)) + # Rules for specific object types. # COMPILE_c = $(CC) $(CFLAGS) $(CFLAGS_c) $(OBJ_CFLAGS) RULE_c = $(Q)$(COMPILE_c) -c $< -o $@ $(POST_O) RULE_c_to_ids.o = $(Q)$(ECHO_E) '$(OBJ_IDS_ASM_NL)' | $(ASSEMBLE_S) -o $@ -RULE_c_to_dbg%.o = $(Q)$(COMPILE_c) -DDBGLVL_MAX=$* -c $< -o $@ $(POST_O) +RULE_c_to_dbg%.o= $(Q)$(COMPILE_c) $(call DBGLVL,$*) -c $< -o $@ $(POST_O) RULE_c_to_c = $(Q)$(COMPILE_c) -E -c $< > $@ RULE_c_to_s = $(Q)$(COMPILE_c) -S -g0 -c $< -o $@ PREPROCESS_S = $(CPP) $(CFLAGS) $(CFLAGS_S) $(OBJ_CFLAGS) ASSEMBLE_S = $(AS) $(ASFLAGS) RULE_S = $(Q)$(PREPROCESS_S) $< | $(ASSEMBLE_S) -o $@ -RULE_S_to_dbg%.o = $(Q)$(PREPROCESS_S) -DDBGLVL_MAX=$* $< | $(ASSEMBLE_S) -o $@ +RULE_S_to_dbg%.o= $(Q)$(PREPROCESS_S) $(call DBGLVL,$*) $< | $(ASSEMBLE_S) -o $@ RULE_S_to_s = $(Q)$(PREPROCESS_S) $< > $@ GENERIC_TARGETS += ids.o dbg%.o c s @@ -1019,10 +1025,12 @@ TGT_LD_FLAGS = $(foreach SYM,$(TGT_LD_ENTRY) $(TGT_LD_DRIVERS) \ # the target. # DEBUG_LIST = $(subst $(COMMA), ,$(DEBUG)) -DEBUG_OBJ_LEVEL = $(firstword $(word 2,$(subst :, ,$(1))) 1) -DEBUG_OBJ_BASE = $(word 1,$(subst :, ,$(1))).dbg$(call DEBUG_OBJ_LEVEL,$(1)) -DEBUG_OBJ = $(BIN)/$(call DEBUG_OBJ_BASE,$(1)).o -DEBUG_ORIG_OBJ = $(BIN)/$(word 1,$(subst :, ,$(1))).o +DEBUG_MAX = $(firstword $(word 2,$(subst :, ,$(1))) 1) +DEBUG_DFLT = $(if $(word 3,$(subst :, ,$(1))),.$(word 3,$(subst :, ,$(1)))) +DEBUG_LEVEL = $(call DEBUG_MAX,$(1))$(call DEBUG_DFLT,$(1)) +DEBUG_BASE = $(firstword $(subst :, ,$(1))).dbg$(call DEBUG_LEVEL,$(1)) +DEBUG_OBJ = $(BIN)/$(call DEBUG_BASE,$(1)).o +DEBUG_ORIG_OBJ = $(BIN)/$(firstword $(subst :, ,$(1))).o DEBUG_OBJS = $(foreach D,$(DEBUG_LIST),$(call DEBUG_OBJ,$(D))) DEBUG_ORIG_OBJS = $(foreach D,$(DEBUG_LIST),$(call DEBUG_ORIG_OBJ,$(D))) BLIB_OBJS = $(DEBUG_OBJS) $(filter-out $(DEBUG_ORIG_OBJS),$(BOBJS)) -- cgit v1.2.3-55-g7522