6948538: CMS: BOT walkers can fall into object allocation and initialization cracks
Summary: GC workers now recognize an intermediate transient state of blocks which are allocated but have not yet completed initialization. blk_start() calls do not attempt to determine the size of a block in the transient state, rather waiting for the block to become initialized so that it is safe to query its size. Audited and ensured the order of initialization of object fields (klass, free bit and size) to respect block state transition protocol. Also included some new assertion checking code enabled in debug mode.
Reviewed-by: chrisphi, johnc, poonam
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################################################################
# JDK TARGETS
################################################################
JDK_JAVA_EXE = $(OUTPUTDIR)/bin/java$(EXE_SUFFIX)
# NO_IMAGES may be set in conjunction with DEV_ONLY
IMAGES_TARGET = images
ifdef DEV_ONLY
ifdef NO_IMAGES
IMAGES_TARGET =
endif
endif
# GENERATE_DOCS determines if we ask for the docs target
DOCS_TARGET = docs
ifeq ($(GENERATE_DOCS),false)
DOCS_TARGET =
endif
JDK_BUILD_TARGETS = sanity all $(DOCS_TARGET) $(IMAGES_TARGET)
JDK_CLOBBER_TARGETS = clobber
JDK_BUILD_ARGUMENTS = $(COMMON_BUILD_ARGUMENTS) \
ALT_OUTPUTDIR=$(ABS_OUTPUTDIR)
ifeq ($(BUILD_LANGTOOLS), true)
JDK_BUILD_ARGUMENTS += ALT_LANGTOOLS_DIST=$(ABS_LANGTOOLS_DIST)
endif
ifeq ($(BUILD_CORBA), true)
JDK_BUILD_ARGUMENTS += ALT_CORBA_DIST=$(ABS_CORBA_DIST)
endif
ifeq ($(BUILD_JAXP), true)
JDK_BUILD_ARGUMENTS += ALT_JAXP_DIST=$(ABS_JAXP_DIST)
endif
ifeq ($(BUILD_JAXWS), true)
JDK_BUILD_ARGUMENTS += ALT_JAXWS_DIST=$(ABS_JAXWS_DIST)
endif
ifeq ($(BUILD_HOTSPOT), true)
JDK_BUILD_ARGUMENTS += ALT_HOTSPOT_IMPORT_PATH=$(HOTSPOT_DIR)/import
endif
JDK_BUILD_ARGUMENTS += \
BUILD_HOTSPOT=$(BUILD_HOTSPOT)
$(JDK_JAVA_EXE):: jdk-build
jdk: jdk-build
jdk-build:
@$(call MakeStart, jdk, $(JDK_BUILD_TARGETS))
( $(CD) $(JDK_TOPDIR)/make && \
$(MAKE) $(JDK_BUILD_TARGETS) $(JDK_BUILD_ARGUMENTS) ; )
@$(call MakeFinish, jdk, $(JDK_BUILD_TARGETS))
jdk-clobber::
@$(call MakeStart, jdk, $(JDK_CLOBBER_TARGETS))
( $(CD) $(JDK_TOPDIR)/make && \
$(MAKE) $(JDK_CLOBBER_TARGETS) $(JDK_BUILD_ARGUMENTS) ; )
@$(call MakeFinish, jdk, $(JDK_CLOBBER_TARGETS))
jdk-sanity::
( $(CD) $(JDK_TOPDIR)/make && \
$(MAKE) sanity HOTSPOT_IMPORT_CHECK=false $(JDK_BUILD_ARGUMENTS) ; )
compare-images: compare-image
compare-image:
@$(call MakeStart, jdk, compare-image)
( $(CD) $(JDK_TOPDIR)/make && \
$(MAKE) ALT_OUTPUTDIR=$(ABS_OUTPUTDIR) compare-image )
@$(call MakeFinish, jdk, compare-image)
compare-images-clobber: compare-image-clobber
compare-image-clobber:
@$(call MakeStart, jdk, compare-image-clobber)
( $(CD) $(JDK_TOPDIR)/make && \
$(MAKE) ALT_OUTPUTDIR=$(ABS_OUTPUTDIR) compare-image-clobber )
@$(call MakeFinish, jdk, compare-image-clobber)
.PHONY: jdk jdk-build jdk-clobber jdk-sanity