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29 July 2024, 15:18:00 UTC
Revision 88fdf75d1bb51d85ba00c466391770056d44bc03 authored by Minchan Kim on 31 July 2012, 23:46:14 UTC, committed by Linus Torvalds on 01 August 2012, 01:42:50 UTC 
mm: warn if pg_data_t isn't initialized with zero
 
Warn if memory-hotplug/boot code doesn't initialize pg_data_t with zero
when it is allocated.  Arch code and memory hotplug already initiailize
pg_data_t.  So this warning should never happen.  I select fields randomly
near the beginning, middle and end of pg_data_t for checking.

This patch isn't for performance but for removing initialization code
which is necessary to add whenever we adds new field to pg_data_t or zone.

Firstly, Andrew suggested clearing out of pg_data_t in MM core part but
Tejun doesn't like it because in the future, some archs can initialize
some fields in arch code and pass them into general MM part so blindly
clearing it out in mm core part would be very annoying.

Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 93180ce
Raw File
Tip revision: 88fdf75d1bb51d85ba00c466391770056d44bc03 authored by Minchan Kim on 31 July 2012, 23:46:14 UTC
mm: warn if pg_data_t isn't initialized with zero
Tip revision: 88fdf75
Makefile.clean 
# ==========================================================================
# Cleaning up
# ==========================================================================

src := $(obj)

PHONY := __clean
__clean:

# Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
# Usage:
# $(Q)$(MAKE) $(clean)=dir
clean := -f $(if $(KBUILD_SRC),$(srctree)/)scripts/Makefile.clean obj

# The filename Kbuild has precedence over Makefile
kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
include $(if $(wildcard $(kbuild-dir)/Kbuild), $(kbuild-dir)/Kbuild, $(kbuild-dir)/Makefile)

# Figure out what we need to build from the various variables
# ==========================================================================

__subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
subdir-y	+= $(__subdir-y)
__subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
subdir-m	+= $(__subdir-m)
__subdir-n	:= $(patsubst %/,%,$(filter %/, $(obj-n)))
subdir-n	+= $(__subdir-n)
__subdir-	:= $(patsubst %/,%,$(filter %/, $(obj-)))
subdir-		+= $(__subdir-)

# Subdirectories we need to descend into

subdir-ym	:= $(sort $(subdir-y) $(subdir-m))
subdir-ymn      := $(sort $(subdir-ym) $(subdir-n) $(subdir-))

# Add subdir path

subdir-ymn	:= $(addprefix $(obj)/,$(subdir-ymn))

# build a list of files to remove, usually relative to the current
# directory

__clean-files	:= $(extra-y) $(always)                  \
		   $(targets) $(clean-files)             \
		   $(host-progs)                         \
		   $(hostprogs-y) $(hostprogs-m) $(hostprogs-)

__clean-files   := $(filter-out $(no-clean-files), $(__clean-files))

# as clean-files is given relative to the current directory, this adds
# a $(obj) prefix, except for absolute paths

__clean-files   := $(wildcard                                               \
                   $(addprefix $(obj)/, $(filter-out /%, $(__clean-files))) \
		   $(filter /%, $(__clean-files)))

# as clean-dirs is given relative to the current directory, this adds
# a $(obj) prefix, except for absolute paths

__clean-dirs    := $(wildcard                                               \
                   $(addprefix $(obj)/, $(filter-out /%, $(clean-dirs)))    \
		   $(filter /%, $(clean-dirs)))

# ==========================================================================

quiet_cmd_clean    = CLEAN   $(obj)
      cmd_clean    = rm -f $(__clean-files)
quiet_cmd_cleandir = CLEAN   $(__clean-dirs)
      cmd_cleandir = rm -rf $(__clean-dirs)


__clean: $(subdir-ymn)
ifneq ($(strip $(__clean-files)),)
	+$(call cmd,clean)
endif
ifneq ($(strip $(__clean-dirs)),)
	+$(call cmd,cleandir)
endif
ifneq ($(strip $(clean-rule)),)
	+$(clean-rule)
endif
	@:


# ===========================================================================
# Generic stuff
# ===========================================================================

# Descending
# ---------------------------------------------------------------------------

PHONY += $(subdir-ymn)
$(subdir-ymn):
	$(Q)$(MAKE) $(clean)=$@

# If quiet is set, only print short version of command

cmd = @$(if $($(quiet)cmd_$(1)),echo '  $($(quiet)cmd_$(1))' &&) $(cmd_$(1))


# Declare the contents of the .PHONY variable as phony.  We keep that
# information in a variable se we can use it in if_changed and friends.

.PHONY: $(PHONY)
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