The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


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FreeBSD/Linux Kernel Cross Reference
sys/conf/kern.pre.mk

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    1 # $FreeBSD$
    2 
    3 # Part of a unified Makefile for building kernels.  This part contains all
    4 # of the definitions that need to be before %BEFORE_DEPEND.
    5 
    6 # Allow user to configure things that only effect src tree builds.
    7 # Note: This is duplicated from src.sys.mk to ensure that we include
    8 # /etc/src.conf when building the kernel. Kernels can be built without
    9 # the rest of /usr/src, but they still always process SRCCONF even though
   10 # the normal mechanisms to prevent that (compiling out of tree) won't
   11 # work. To ensure they do work, we have to duplicate thee few lines here.
   12 SRCCONF?=       /etc/src.conf
   13 .if (exists(${SRCCONF}) || ${SRCCONF} != "/etc/src.conf") && !target(_srcconf_included_)
   14 .include "${SRCCONF}"
   15 _srcconf_included_:
   16 .endif
   17 
   18 .include <bsd.own.mk>
   19 .include <bsd.compiler.mk>
   20 .include "kern.opts.mk"
   21 
   22 # The kernel build always occurs in the object directory which is .CURDIR.
   23 .if ${.MAKE.MODE:Unormal:Mmeta}
   24 .MAKE.MODE+=    curdirOk=yes
   25 .endif
   26 
   27 # The kernel build always expects .OBJDIR=.CURDIR.
   28 .OBJDIR: ${.CURDIR}
   29 
   30 .if defined(NO_OBJWALK) || ${MK_AUTO_OBJ} == "yes"
   31 NO_OBJWALK=             t
   32 NO_MODULES_OBJ= t
   33 .endif
   34 .if !defined(NO_OBJWALK)
   35 _obj=           obj
   36 .endif
   37 
   38 # Can be overridden by makeoptions or /etc/make.conf
   39 KERNEL_KO?=     kernel
   40 KERNEL?=        kernel
   41 KODIR?=         /boot/${KERNEL}
   42 LDSCRIPT_NAME?= ldscript.$M
   43 LDSCRIPT?=      $S/conf/${LDSCRIPT_NAME}
   44 
   45 M=              ${MACHINE}
   46 
   47 AWK?=           awk
   48 CP?=            cp
   49 ELFDUMP?=       elfdump
   50 NM?=            nm
   51 OBJCOPY?=       objcopy
   52 SIZE?=          size
   53 
   54 .if defined(DEBUG)
   55 CTFFLAGS+=      -g
   56 .endif
   57 .if ${MACHINE_CPUARCH} == "amd64" && ${COMPILER_TYPE} != "clang"
   58 _COPTFLAGS_EXTRA=-frename-registers
   59 .else
   60 _COPTFLAGS_EXTRA=
   61 .endif
   62 COPTFLAGS?=-O2 -pipe ${_COPTFLAGS_EXTRA}
   63 .if !empty(COPTFLAGS:M-O[23s]) && empty(COPTFLAGS:M-fno-strict-aliasing)
   64 COPTFLAGS+= -fno-strict-aliasing
   65 .endif
   66 .if !defined(NO_CPU_COPTFLAGS)
   67 COPTFLAGS+= ${_CPUCFLAGS}
   68 .endif
   69 NOSTDINC= -nostdinc
   70 
   71 INCLUDES= ${NOSTDINC} ${INCLMAGIC} -I. -I$S -I$S/contrib/ck/include
   72 
   73 CFLAGS= ${COPTFLAGS} ${DEBUG}
   74 CFLAGS+= ${INCLUDES} -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h
   75 CFLAGS_PARAM_INLINE_UNIT_GROWTH?=100
   76 CFLAGS_PARAM_LARGE_FUNCTION_GROWTH?=1000
   77 CFLAGS.gcc+= -fms-extensions -finline-limit=${INLINE_LIMIT}
   78 CFLAGS.gcc+= --param inline-unit-growth=${CFLAGS_PARAM_INLINE_UNIT_GROWTH}
   79 CFLAGS.gcc+= --param large-function-growth=${CFLAGS_PARAM_LARGE_FUNCTION_GROWTH}
   80 CFLAGS.gcc+= -fms-extensions
   81 .if defined(CFLAGS_ARCH_PARAMS)
   82 CFLAGS.gcc+=${CFLAGS_ARCH_PARAMS}
   83 .endif
   84 WERROR?=        -Werror
   85 # The following should be removed no earlier than LLVM11 being imported into the
   86 # tree, to ensure we don't regress the build.  LLVM11 and GCC10 will switch the
   87 # default over to -fno-common, making this redundant.
   88 CFLAGS+=        -fno-common
   89 
   90 # XXX LOCORE means "don't declare C stuff" not "for locore.s".
   91 ASM_CFLAGS= -x assembler-with-cpp -DLOCORE ${CFLAGS} ${ASM_CFLAGS.${.IMPSRC:T}}
   92 
   93 COMPAT_FREEBSD32_ENABLED!= grep COMPAT_FREEBSD32 opt_global.h || true ; echo
   94 
   95 KASAN_ENABLED!= grep KASAN opt_global.h || true ; echo
   96 .if !empty(KASAN_ENABLED)
   97 SAN_CFLAGS+=    -DSAN_NEEDS_INTERCEPTORS -DSAN_INTERCEPTOR_PREFIX=kasan \
   98                 -fsanitize=kernel-address \
   99                 -mllvm -asan-stack=true \
  100                 -mllvm -asan-instrument-dynamic-allocas=true \
  101                 -mllvm -asan-globals=true \
  102                 -mllvm -asan-use-after-scope=true \
  103                 -mllvm -asan-instrumentation-with-call-threshold=0 \
  104                 -mllvm -asan-instrument-byval=false
  105 .endif
  106 
  107 KCSAN_ENABLED!= grep KCSAN opt_global.h || true ; echo
  108 .if !empty(KCSAN_ENABLED)
  109 SAN_CFLAGS+=    -DSAN_NEEDS_INTERCEPTORS -DSAN_INTERCEPTOR_PREFIX=kcsan \
  110                 -fsanitize=thread
  111 .endif
  112 
  113 KMSAN_ENABLED!= grep KMSAN opt_global.h || true ; echo
  114 .if !empty(KMSAN_ENABLED)
  115 SAN_CFLAGS+=    -DSAN_NEEDS_INTERCEPTORS -DSAN_INTERCEPTOR_PREFIX=kmsan \
  116                 -fsanitize=kernel-memory
  117 .endif
  118 
  119 KUBSAN_ENABLED!=        grep KUBSAN opt_global.h || true ; echo
  120 .if !empty(KUBSAN_ENABLED)
  121 SAN_CFLAGS+=    -fsanitize=undefined
  122 .endif
  123 
  124 COVERAGE_ENABLED!=      grep COVERAGE opt_global.h || true ; echo
  125 .if !empty(COVERAGE_ENABLED)
  126 .if ${COMPILER_TYPE} == "clang" || \
  127     (${COMPILER_TYPE} == "gcc" && ${COMPILER_VERSION} >= 80100)
  128 SAN_CFLAGS+=    -fsanitize-coverage=trace-pc,trace-cmp
  129 .else
  130 SAN_CFLAGS+=    -fsanitize-coverage=trace-pc
  131 .endif
  132 .endif
  133 
  134 CFLAGS+=        ${SAN_CFLAGS}
  135 
  136 GCOV_ENABLED!=  grep GCOV opt_global.h || true ; echo
  137 .if !empty(GCOV_ENABLED)
  138 .if ${COMPILER_TYPE} == "gcc"
  139 GCOV_CFLAGS+=    -fprofile-arcs -ftest-coverage
  140 .endif
  141 .endif
  142 
  143 CFLAGS+=        ${GCOV_CFLAGS}
  144 
  145 # Put configuration-specific C flags last so that they can override
  146 # the others.
  147 CFLAGS+=        ${CONF_CFLAGS}
  148 
  149 .if defined(LINKER_FEATURES) && ${LINKER_FEATURES:Mbuild-id}
  150 LDFLAGS+=       --build-id=sha1
  151 .endif
  152 
  153 .if (${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "amd64" || \
  154     ${MACHINE_CPUARCH} == "i386" || ${MACHINE} == "powerpc") && \
  155     defined(LINKER_FEATURES) && ${LINKER_FEATURES:Mifunc} == "" && \
  156     !make(install)
  157 .error amd64/arm64/i386/ppc* kernel requires linker ifunc support
  158 .endif
  159 .if ${MACHINE_CPUARCH} == "amd64"
  160 LDFLAGS+=       -z max-page-size=2097152
  161 .if ${LINKER_TYPE} != "lld"
  162 LDFLAGS+=       -z common-page-size=4096
  163 .else
  164 .if defined(LINKER_FEATURES) && !${LINKER_FEATURES:Mifunc-noplt}
  165 .warning "Linker ${LD} does not support -z ifunc-noplt -> ifunc calls are unoptimized."
  166 .else
  167 LDFLAGS+=       -z notext -z ifunc-noplt
  168 .endif
  169 .endif
  170 .endif  # ${MACHINE_CPUARCH} == "amd64"
  171 
  172 .if ${MACHINE_CPUARCH} == "riscv"
  173 # Hack: Work around undefined weak symbols being out of range when linking with
  174 # LLD (address is a PC-relative calculation, and BFD works around this by
  175 # rewriting the instructions to generate an absolute address of 0); -fPIE
  176 # avoids this since it uses the GOT for all extern symbols, which is overly
  177 # inefficient for us. Drop once undefined weak symbols work with medany.
  178 .if ${LINKER_TYPE} == "lld"
  179 CFLAGS+=        -fPIE
  180 .endif
  181 .endif
  182 
  183 NORMAL_C= ${CC} -c ${CFLAGS} ${WERROR} ${.IMPSRC}
  184 NORMAL_S= ${CC:N${CCACHE_BIN}} -c ${ASM_CFLAGS} ${WERROR} ${.IMPSRC}
  185 NORMAL_C_NOWERROR= ${CC} -c ${CFLAGS} ${.IMPSRC}
  186 
  187 NORMAL_M= ${AWK} -f $S/tools/makeobjops.awk ${.IMPSRC} -c ; \
  188           ${CC} -c ${CFLAGS} ${WERROR} ${.PREFIX}.c
  189 
  190 NORMAL_FW= uudecode -o ${.TARGET} ${.ALLSRC}
  191 NORMAL_FWO= ${CC:N${CCACHE_BIN}} -c ${ASM_CFLAGS} ${WERROR} -o ${.TARGET} \
  192         $S/kern/firmw.S -DFIRMW_FILE="${.ALLSRC:M*.fw}" \
  193         -DFIRMW_SYMBOL="${.ALLSRC:M*.fw:C/[-.\/]/_/g}"
  194 
  195 # for ZSTD in the kernel (include zstd/lib/freebsd before other CFLAGS)
  196 ZSTD_C= ${CC} -c -DZSTD_HEAPMODE=1 -I$S/contrib/zstd/lib/freebsd ${CFLAGS} \
  197         -I$S/contrib/zstd/lib -I$S/contrib/zstd/lib/common ${WERROR} \
  198         -Wno-missing-prototypes -U__BMI__ -DZSTD_NO_INTRINSICS ${.IMPSRC}
  199 # https://github.com/facebook/zstd/commit/812e8f2a [zstd 1.4.1]
  200 # "Note that [GCC] autovectorization still does not do a good job on the
  201 # optimized version, so it's turned off via attribute and flag.  I found
  202 # that neither attribute nor command-line flag were entirely successful in
  203 # turning off vectorization, which is why there were both."
  204 .if ${COMPILER_TYPE} == "gcc"
  205 ZSTD_DECOMPRESS_BLOCK_FLAGS= -fno-tree-vectorize
  206 .endif
  207 
  208 ZINCDIR=$S/contrib/openzfs/include
  209 # Common for dtrace / zfs
  210 CDDL_CFLAGS=    \
  211         -DFREEBSD_NAMECACHE \
  212         -D_SYS_VMEM_H_ \
  213         -D__KERNEL \
  214         -D__KERNEL__ \
  215         -nostdinc \
  216         -include $S/modules/zfs/static_ccompile.h \
  217         -I${ZINCDIR} \
  218         -I${ZINCDIR}/os/freebsd \
  219         -I${ZINCDIR}/os/freebsd/spl \
  220         -I${ZINCDIR}/os/freebsd/zfs  \
  221         -I$S/modules/zfs \
  222         -I$S/contrib/openzfs/module/zstd/include \
  223         ${CFLAGS} \
  224         -Wno-cast-qual \
  225         -Wno-duplicate-decl-specifier \
  226         -Wno-missing-braces \
  227         -Wno-missing-prototypes \
  228         -Wno-nested-externs \
  229         -Wno-parentheses \
  230         -Wno-pointer-arith \
  231         -Wno-strict-prototypes \
  232         -Wno-switch \
  233         -Wno-undef \
  234         -Wno-uninitialized \
  235         -Wno-unknown-pragmas \
  236         -Wno-unused \
  237         -include ${ZINCDIR}/os/freebsd/spl/sys/ccompile.h \
  238         -I$S/cddl/contrib/opensolaris/uts/common \
  239         -I$S -I$S/cddl/compat/opensolaris
  240 CDDL_C=         ${CC} -c ${CDDL_CFLAGS} ${WERROR} ${.IMPSRC}
  241 
  242 # Special flags for managing the compat compiles for ZFS
  243 ZFS_CFLAGS+=    -I$S/contrib/openzfs/module/icp/include \
  244         ${CDDL_CFLAGS} -DBUILDING_ZFS -DHAVE_UIO_ZEROCOPY \
  245         -DWITH_NETDUMP -D__KERNEL__ -D_SYS_CONDVAR_H_ -DSMP \
  246         -DIN_FREEBSD_BASE
  247 
  248 .if ${MACHINE_ARCH} == "amd64"
  249 ZFS_CFLAGS+= -D__x86_64 -DHAVE_SSE2 -DHAVE_SSSE3 -DHAVE_SSE4_1 -DHAVE_SSE4_2 \
  250         -DHAVE_AVX -DHAVE_AVX2 -DHAVE_AVX512F -DHAVE_AVX512VL -DHAVE_AVX512BW
  251 .endif
  252 
  253 .if ${MACHINE_ARCH} == "i386" || ${MACHINE_ARCH} == "powerpc" || \
  254         ${MACHINE_ARCH} == "powerpcspe" || ${MACHINE_ARCH} == "arm"
  255 ZFS_CFLAGS+= -DBITS_PER_LONG=32
  256 .else
  257 ZFS_CFLAGS+= -DBITS_PER_LONG=64
  258 .endif
  259 
  260 
  261 ZFS_ASM_CFLAGS= -x assembler-with-cpp -DLOCORE ${ZFS_CFLAGS}
  262 ZFS_C=          ${CC} -c ${ZFS_CFLAGS} ${WERROR} ${.IMPSRC}
  263 ZFS_RPC_C=      ${CC} -c ${ZFS_CFLAGS} -DHAVE_RPC_TYPES ${WERROR} ${.IMPSRC}
  264 ZFS_S=          ${CC} -c ${ZFS_ASM_CFLAGS} ${WERROR} ${.IMPSRC}
  265 
  266 # ATH driver
  267 ATH_CFLAGS=     -I${SRCTOP}/sys/dev/ath ${NO_WUNUSED_BUT_SET_VARIABLE}
  268 ATH_C=          ${CC} -c ${CFLAGS} ${WERROR} ${ATH_CFLAGS} ${.IMPSRC}
  269 
  270 # Special flags for managing the compat compiles for DTrace
  271 DTRACE_CFLAGS=  -DBUILDING_DTRACE ${CDDL_CFLAGS} -I$S/cddl/dev/dtrace -I$S/cddl/dev/dtrace/${MACHINE_CPUARCH}
  272 .if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386"
  273 DTRACE_CFLAGS+= -I$S/cddl/contrib/opensolaris/uts/intel -I$S/cddl/dev/dtrace/x86
  274 .endif
  275 DTRACE_CFLAGS+= -I$S/cddl/contrib/opensolaris/common/util -I$S -DDIS_MEM -DSMP -I$S/cddl/compat/opensolaris
  276 DTRACE_CFLAGS+= -I$S/cddl/contrib/opensolaris/uts/common
  277 DTRACE_ASM_CFLAGS=      -x assembler-with-cpp -DLOCORE ${DTRACE_CFLAGS}
  278 DTRACE_C=       ${CC} -c ${DTRACE_CFLAGS}       ${WERROR} ${.IMPSRC}
  279 DTRACE_S=       ${CC} -c ${DTRACE_ASM_CFLAGS}   ${WERROR} ${.IMPSRC}
  280 
  281 # Special flags for managing the compat compiles for DTrace/FBT
  282 FBT_CFLAGS=     -DBUILDING_DTRACE -nostdinc -I$S/cddl/dev/fbt/${MACHINE_CPUARCH} -I$S/cddl/dev/fbt ${CDDL_CFLAGS} -I$S/cddl/compat/opensolaris -I$S/cddl/contrib/opensolaris/uts/common  
  283 .if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386"
  284 FBT_CFLAGS+=    -I$S/cddl/dev/fbt/x86
  285 .endif
  286 FBT_C=          ${CC} -c ${FBT_CFLAGS}          ${WERROR} ${.IMPSRC}
  287 
  288 .if ${MK_CTF} != "no"
  289 NORMAL_CTFCONVERT=      ${CTFCONVERT} ${CTFFLAGS} ${.TARGET}
  290 .elif ${MAKE_VERSION} >= 5201111300
  291 NORMAL_CTFCONVERT=
  292 .else
  293 NORMAL_CTFCONVERT=      @:
  294 .endif
  295 
  296 # Linux Kernel Programming Interface C-flags
  297 LINUXKPI_INCLUDES=      -I$S/compat/linuxkpi/common/include \
  298                         -I$S/compat/linuxkpi/dummy/include
  299 LINUXKPI_C=             ${NORMAL_C} ${LINUXKPI_INCLUDES}
  300 
  301 # Infiniband C flags.  Correct include paths and omit errors that linux
  302 # does not honor.
  303 OFEDINCLUDES=   -I$S/ofed/include -I$S/ofed/include/uapi ${LINUXKPI_INCLUDES}
  304 OFEDNOERR=      -Wno-cast-qual -Wno-pointer-arith
  305 OFEDCFLAGS=     ${CFLAGS:N-I*} -DCONFIG_INFINIBAND_USER_MEM \
  306                 ${OFEDINCLUDES} ${CFLAGS:M-I*} ${OFEDNOERR}
  307 OFED_C_NOIMP=   ${CC} -c -o ${.TARGET} ${OFEDCFLAGS} ${WERROR}
  308 OFED_C=         ${OFED_C_NOIMP} ${.IMPSRC}
  309 
  310 # mlxfw C flags.
  311 MLXFW_C=        ${OFED_C_NOIMP} \
  312                 -I${SRCTOP}/sys/contrib/xz-embedded/freebsd \
  313                 -I${SRCTOP}/sys/contrib/xz-embedded/linux/lib/xz \
  314                 ${.IMPSRC}
  315 
  316 GEN_CFILES= $S/$M/$M/genassym.c ${MFILES:T:S/.m$/.c/}
  317 SYSTEM_CFILES= config.c env.c hints.c vnode_if.c
  318 SYSTEM_DEP= Makefile ${SYSTEM_OBJS}
  319 SYSTEM_OBJS= locore.o ${MDOBJS} ${OBJS}
  320 SYSTEM_OBJS+= ${SYSTEM_CFILES:.c=.o}
  321 SYSTEM_OBJS+= force-dynamic-hack.pico
  322 
  323 KEYMAP=kbdcontrol -P ${SRCTOP}/share/vt/keymaps -P ${SRCTOP}/share/syscons/keymaps
  324 KEYMAP_FIX=sed -e 's/^static keymap_t.* = /static keymap_t key_map = /' -e 's/^static accentmap_t.* = /static accentmap_t accent_map = /'
  325 
  326 MD_ROOT_SIZE_CONFIGURED!=       grep MD_ROOT_SIZE opt_md.h || true ; echo
  327 .if ${MFS_IMAGE:Uno} != "no"
  328 .if empty(MD_ROOT_SIZE_CONFIGURED)
  329 SYSTEM_OBJS+= embedfs_${MFS_IMAGE:T:R}.o
  330 .endif
  331 .endif
  332 SYSTEM_LD_BASECMD= \
  333         ${LD} -m ${LD_EMULATION} -Bdynamic -T ${LDSCRIPT} ${_LDFLAGS} \
  334         --no-warn-mismatch --warn-common --export-dynamic \
  335         --dynamic-linker /red/herring -X
  336 SYSTEM_LD= @${SYSTEM_LD_BASECMD} -o ${.TARGET} ${SYSTEM_OBJS} vers.o
  337 SYSTEM_LD_TAIL= @${OBJCOPY} --strip-symbol gcc2_compiled. ${.TARGET} ; \
  338         ${SIZE} ${.TARGET} ; chmod 755 ${.TARGET}
  339 SYSTEM_DEP+= ${LDSCRIPT}
  340 
  341 # Calculate path for .m files early, if needed.
  342 .if !defined(NO_MODULES) && !defined(__MPATH) && !make(install) && \
  343     (empty(.MAKEFLAGS:M-V) || defined(NO_SKIP_MPATH))
  344 __MPATH!=find ${S:tA}/ -name \*_if.m
  345 .endif
  346 
  347 # MKMODULESENV is set here so that port makefiles can augment
  348 # them.
  349 
  350 MKMODULESENV+=  MAKEOBJDIRPREFIX=${.OBJDIR}/modules KMODDIR=${KODIR}
  351 MKMODULESENV+=  MACHINE_CPUARCH=${MACHINE_CPUARCH}
  352 MKMODULESENV+=  MACHINE=${MACHINE} MACHINE_ARCH=${MACHINE_ARCH}
  353 MKMODULESENV+=  MODULES_EXTRA="${MODULES_EXTRA}" WITHOUT_MODULES="${WITHOUT_MODULES}"
  354 MKMODULESENV+=  ARCH_FLAGS="${ARCH_FLAGS}"
  355 .if (${KERN_IDENT} == LINT)
  356 MKMODULESENV+=  ALL_MODULES=LINT
  357 .endif
  358 .if defined(MODULES_OVERRIDE)
  359 MKMODULESENV+=  MODULES_OVERRIDE="${MODULES_OVERRIDE}"
  360 .endif
  361 .if defined(DEBUG)
  362 MKMODULESENV+=  DEBUG_FLAGS="${DEBUG}"
  363 .endif
  364 .if !defined(NO_MODULES)
  365 MKMODULESENV+=  __MPATH="${__MPATH}"
  366 .endif
  367 
  368 # Detect kernel config options that force stack frames to be turned on.
  369 DDB_ENABLED!=   grep DDB opt_ddb.h || true ; echo
  370 DTRACE_ENABLED!=grep KDTRACE_FRAME opt_kdtrace.h || true ; echo
  371 HWPMC_ENABLED!= grep HWPMC opt_hwpmc_hooks.h || true ; echo

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