bsd.subdir.mk: Only recurse on called targets, rather than dependencies.

This is to fix 'make all' causing it to recurse on both 'all' and 'buildconfig'
due to 'buildconfig' being in ALL_SUBDIR_TARGETS and being a dependency of
'all'.

This now adds all of the '*includes', '*files' targets as subdir targets,
allowing them to recurse.

This also removes the need for some 'realinstall' hacks in bsd.subdir.mk since
it no longer recurses; only 'install' will recurse and call the proper
'beforeinstall', 'realinstall', and 'afterinstall' in each sub-directory.

This fixes 'make includes' and 'make files' to not be a rerolled ${MAKE}
sub-shell but to rather just recurse on 'inclues' and 'files'.  This avoids
various issues such as the one fixed in r289462.  As such revert Makefile.inc1
back to using 'includes' which avoids an extra tree walk and parallelizes
the includes phases better.

Makefile.inc1 includes a guard so that 'make all' will not use SUBDIR_PARALLEL,
added in r289438.  This is so users do not get a probably broken build if they
run 'make all' from the top-level.  Before the change in this commit, the
workaround for 'make everything' was 'par-all' which would depend on 'all' and
cause a proper parallel recursion.  Now that will not work so a new
_PARALLEL_SUBUDIR_OK is used to allow it.

This is still part of an effort to combine bsd.(files|incs|confs).mk and move
some of its logic out of bsd.subdir.mk, as attempted in r289282 and reverted in
r289331.  This commit fixes the problems found there which was mostly double
recursing during 'includes' which would recurse on itself and 'buildincludes'
and 'installincludes', all in parallel.  The logic is still in bsd.subdir.mk
for now.

I've been cautious about this commit but have experienced no breakage on the
tree except for the 'par-all' case which was already a hack.  If something foo
is depending on something bar that should recurse, it is very likely that the
foo target is being recursed on already meaning that bar will still effectively
recurse once sub-directories call foo.

Discussed on:	arch@
MFC after:	never
Sponsored by:	EMC / Isilon Storage Division

share/mk/bsd.subdir.mk

@@ -36,10 +36,11 @@
 .if !target(__<bsd.subdir.mk>__)
 __<bsd.subdir.mk>__:
 
-ALL_SUBDIR_TARGETS= all all-man buildconfig checkdpadd clean cleandepend \
-		    cleandir cleanilinks cleanobj depend distribute \
-		    installconfig lint maninstall manlint obj objlink \
-		    realinstall regress tags \
+ALL_SUBDIR_TARGETS= all all-man buildconfig buildfiles buildincludes \
+		    checkdpadd clean cleandepend cleandir cleanilinks \
+		    cleanobj depend distribute files includes installconfig \
+		    installfiles installincludes install lint maninstall \
+		    manlint obj objlink regress tags \
 		    ${SUBDIR_TARGETS}
 
 # Described above.
@@ -71,6 +72,27 @@ distribute: .MAKE
 .endfor
 .endif
 
+# Convenience targets to run 'build${target}' and 'install${target}' when
+# calling 'make ${target}'.
+.for __target in files includes
+.if !target(${__target})
+${__target}:	build${__target} install${__target}
+.ORDER:		build${__target} install${__target}
+.endif
+.endfor
+
+# Make 'install' supports a before and after target.  Actual install
+# hooks are placed in 'realinstall'.
+.if !target(install)
+.for __stage in before real after
+.if !target(${__stage}install)
+${__stage}install:
+.endif
+.endfor
+install:	beforeinstall realinstall afterinstall
+.ORDER:		beforeinstall realinstall afterinstall
+.endif
+
 # Subdir code shared among 'make <subdir>', 'make <target>' and SUBDIR_PARALLEL.
 _SUBDIR_SH=	\
 		if test -d ${.CURDIR}/$${dir}.${MACHINE_ARCH}; then \
@@ -82,7 +104,7 @@ _SUBDIR_SH=	\
 
 _SUBDIR: .USEBEFORE
 .if defined(SUBDIR) && !empty(SUBDIR) && !defined(NO_SUBDIR)
-	@${_+_}target=${.TARGET:S,realinstall,install,}; \
+	@${_+_}target=${.TARGET}; \
 	    for dir in ${SUBDIR:N.WAIT}; do ( ${_SUBDIR_SH} ); done
 .endif
 
@@ -101,6 +123,10 @@ SUBDIR:=	${SUBDIR:N.WAIT}
 .else
 _is_standalone_target=	0
 .endif
+# Only recurse on directly-called targets.  I.e., don't recurse on dependencies
+# such as 'install' becoming {before,real,after}install, just recurse
+# 'install'.
+.if make(${__target})
 .if defined(SUBDIR_PARALLEL) || ${_is_standalone_target} == 1
 __subdir_targets=
 .for __dir in ${SUBDIR}
@@ -116,7 +142,7 @@ __deps+= ${__target}_subdir_${__dep}
 .endif
 ${__target}_subdir_${__dir}: .PHONY .MAKE ${__deps}
 .if !defined(NO_SUBDIR)
-	@${_+_}target=${__target:realinstall=install}; \
+	@${_+_}target=${__target}; \
 	    dir=${__dir}; \
 	    ${_SUBDIR_SH};
 .endif
@@ -126,35 +152,11 @@ ${__target}: ${__subdir_targets}
 .else
 ${__target}: _SUBDIR
 .endif	# SUBDIR_PARALLEL || _is_standalone_target
+.elif !target(${__target})
+${__target}:
+.endif	# make(${__target})
 .endfor	# __target in ${ALL_SUBDIR_TARGETS}
 
-# This is to support 'make includes' calling 'make buildincludes' and
-# 'make installincludes' in the proper order, and to support these
-# targets as SUBDIR_TARGETS.
-.for __target in files includes
-.for __stage in build install
-${__stage}${__target}:
-.if make(${__stage}${__target})
-${__stage}${__target}: _SUBDIR
-.endif
-.endfor
-.if !target(${__target})
-${__target}: .MAKE
-	${_+_}cd ${.CURDIR}; ${MAKE} build${__target}; ${MAKE} install${__target}
-.endif
-.endfor
-
-.endif
-
-.if !target(install)
-.if !target(beforeinstall)
-beforeinstall:
-.endif
-.if !target(afterinstall)
-afterinstall:
-.endif
-install: beforeinstall realinstall afterinstall
-.ORDER: beforeinstall realinstall afterinstall
-.endif
+.endif	# !target(_SUBDIR)
 
 .endif