Initial public release

.gitignore

+# editors
+*~
+
+# general
+core.*
+
+# build system
+
+.deps/
+.libs/
+autom4te.cache/
+build-aux/
+m4/
+
+*.la
+*.lo
+*.o
+*.tar.gz
+
+Makefile
+Makefile.in
+aclocal.m4
+config.h
+config.h.in
+config.log
+config.status
+configure
+libtool
+stamp-h1
+
+# test suite
+
+*.log
+*.trs
+fellowfile
+
+# vmodtool
+
+vcc_*_if.[ch]
+vmod_slash.rst
+
+# vsctool
+
+VSC_*.[ch]
+VSC_*.rst
+
+# dot
+src/fcs_states.dot
+
+# man
+
+*.1
+*.7
+*_options.rst
+*_synopsis.rst
+vmod_*.3
+slashmap.rst
+
+# bin
+
+slashmap
+slash
+buddy_test
+buddy_test_witness
+buddy_test_when
+fellow_log_test
+fellow_log_test_ndebug
+fellow_cache_test
+fellow_log_dbg
+
+# coverage
+
+*.gcda
+*.gcno
+/src/coverage

COPYING

+The slash project is provided under:
+
+	SPDX-License-Identifier: LGPL-2.1-only
+
+with the exception of some files taken from the Varnish-Cache project
+which are licensed under
+
+	SPDX-License-Identifier: BSD-2-Clause
+
+Both licences are provided in the LICENSES directory.
\ No newline at end of file

INSTALL.rst

+================================
+SLASH/ Installation Instructions
+================================
+
+.. role:: ref(emphasis)
+
+Installing from Source
+======================
+
+.. _Compiling Varnish from source: https://varnish-cache.org/docs/trunk/installation/install_source.html
+
+generic
+-------
+
+* Compile and install varnish-cache 7.2.0 or later by the
+  `Compiling Varnish from source`_ documentation.
+
+* Optionally, install the following additional prerequisites:
+
+recommendations for optimal fellow storage performance
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. _liburing: https://github.com/axboe/liburing.git
+.. _xxhash: https://github.com/Cyan4973/xxHash
+
+* On Linux, it is strongly recommended to add io_uring support by
+  installing kernel >= 5.10 (better: >= 5.13) and `liburing`_.
+
+* For optimal performance, it is recommended to install `xxhash`_ and
+  later use ``xxh3_64`` or ``xxh3_128`` by setting the ``hash_obj``
+  and ``hash_log`` tuneables.
+
+  Note that a fellow storage using any of the `xxhash`_ hashes can
+  only be loaded by an instance with `xxhash`_ support compiled in.
+
+compiling
+~~~~~~~~~
+
+* set and export the ``VARNISHSRC`` environment variable to point to
+  the varnish-cache source tree
+
+* In the ``slash`` source tree, run::
+
+    ./bootstrap
+    make check
+    make install
+
+The last step will probably need to be run as root (e.g. using ``sudo``).
+
+When installation has succeeded, continue with the `Next Steps`_.
+
+Debian/Ubuntu
+-------------
+
+This guide was written based on:
+
+* Debian 11 base install
+* Varnish-Cache binary packages
+
+Add the packagecloud repository, if not already done::
+
+  sudo apt-get install curl
+  curl -sO \
+  https://packagecloud.io/install/repositories/varnishcache/varnish72/script.deb.sh
+  # REVIEW script.deb.sh and continue only if considered safe
+  sudo bash script.deb.sh
+
+Install varnish-cache dev package and other required packages::
+
+  sudo apt-get install -y \
+    varnish-dev \
+    git \
+    autoconf \
+    autoconf-archive \
+    automake \
+    libtool \
+    gcc \
+    python3-docutils \
+    python3-sphinx \
+    libpcre2-dev \
+    libreadline-dev \
+    liburing-dev \
+    libxxhash-dev \
+    libncurses-dev
+
+Download and extract the varnish-cache source code for the installed
+version, and export the ``VARNISHSRC`` environment variable to the right
+directory::
+
+  v=$(/usr/sbin/varnishd -V 2>&1 | grep -Eo 'varnish-[0-9.]+')
+  curl -LO \
+    https://github.com/varnishcache/varnish-cache/archive/refs/tags/${v}.tar.gz
+  tar xf ${v}.tar.gz
+  VARNISHSRC=$(realpath varnish-cache-${v})
+  export VARNISHSRC
+
+Build required components from varnish-cache::
+
+  ( pushd $VARNISHSRC && \
+    ./autogen.des && \
+    pushd include && \
+    make vcs_version.h && \
+    popd && pushd lib/libvarnish && \
+    make libvarnish.la && \
+    popd && pushd lib/libvsc &&
+    make VSC_main.c \
+    )
+
+Clone this repository::
+
+  git clone http://code.uplex.de/uplex-varnish/slash.git
+
+Enter the ``slash`` directory and call ``bootstrap``::
+
+  cd slash
+  ./bootstrap
+
+A summary similar to the one shown below should be output. In
+particular, ``xxhash: yes`` and ``uring: yes`` should be contained::
+
+	==== slash 0.9 ====
+
+	varnish:      7.2.1
+	prefix:       /usr
+	vmoddir:      /usr/lib/varnish/vmods
+	vcldir:       ${datarootdir}/varnish/vcl
+	pkgvcldir:    ${vcldir}/${PACKAGE}
+
+	compiler:     gcc
+	cflags:       -g -O2 -fstack-protector-all
+	ldflags:
+
+	xxhash:       yes
+	uring:        yes
+	aio:          no
+
+Build, test and install SLASH/::
+
+  make check && sudo make install
+
+Configuration options
+---------------------
+
+.. _autoconf: https://www.gnu.org/software/autoconf/
+
+Among other things, ``bootstrap`` invokes the ``configure`` script
+generated by `autoconf`_, and any command-line options given with
+``bootstrap`` are passed on to ``configure``. For example,
+``VARNISHSRC`` can be specified like this (since ``bootstrap`` is the
+only step that requires it)::
+
+  bootstrap VARNISHSRC=/path/to/varnish-cache
+
+CLI options can also be used, for example, to set ``CFLAGS``, select
+the C compiler (with ``CC``), or specify the installation prefix.
+``bootstrap --help`` (which invokes ``configure --help``) shows all of
+the relevant variables and available options.
+
+For most installations, the default values (with no CLI options, as
+shown above) are sufficient.
+
+Next Steps
+----------
+
+.. _Next Steps:
+
+Now you should be ready to go.
+
+Consult the :ref:`vmod_slash(3)` and :ref:`slashmap(1)` man pages for
+detailed information on how to configure, use and monitor the SLASH/
+storage engines.
+
+System Setup for Optimal Performance
+====================================
+
+buddy & fellow memory cache
+---------------------------
+
+For the time being, these recommendations only apply to Linux.
+
+The `buddy` allocator, which is also used by the memory cache of
+`fellow`, will, by default, attempt to allocate memory from huge pages
+and try to lock pages in RAM and thus prevent paging.
+
+huge pages
+~~~~~~~~~~
+
+To the best of our knowledge, best performance is thus achieved by
+ensuring that the system has sufficient huge pages reserved by
+
+* either using the kernel command line, for example by adding to
+  ``/etc/default/grub``::
+
+    GRUB_CMDLINE_LINUX="hugepagesz=1GB hugepages=300"
+
+  to configure 300GB of 1GB huge pages at boot and rebooting
+
+* or by applying the same configuration at runtime through::
+
+    echo 300 \
+    >/sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
+
+  to, again, configure 300GB of 1GB huge pages.
+
+The 300GB used in these examples have to be adjusted approriately to
+the desired memory cache size.
+
+Alternatively, 2MB huge pages can be used where 1GB pages are not
+available.
+
+locked memory
+~~~~~~~~~~~~~
+
+:ref:`varnishd(1)` should be started with a limit on locked memory
+higher than the configured memory size. We recommend to configure no
+limit on locked memory by calling::
+
+  ulimit -l unlimited
+
+or using::
+
+  LimitMEMLOCK=infinity
+
+with :ref:`systemd(1)`, or whatever appropriate method to lift the
+limit on locked memory.
+
+fellow storage
+--------------
+
+`fellow` uses its own memory caching strategy, so double caching by
+the operating system should be avoided. `fellow` thus tries to open
+the storage path with ``O_DIRECT``, where available.
+
+Nonetheless, to the best of our knowledge, avoiding the file system
+overhead results in optimal performance. Where possible, the `fellow`
+*path* should therefore point to a disk storage device. Using a mirror
+or mirror/stripe (RAID1 or RAID10) is recommended for optimal
+resilience.
+
+As the IO pattern of `fellow` usually is highly random and because
+access times are crucial for overall latency, using storage with the
+lowest possible access times for random access is highly
+recommended. Flash based storage (SSD, NVMe) usually falls into this
+category.

LICENSES/BSD-2-Clause

+Valid-License-Identifier: BSD-2-Clause
+SPDX-URL: https://spdx.org/licenses/BSD-2-Clause.html
+Usage-Guide:
+  To use the BSD 2-clause "Simplified" License put the following SPDX
+  tag/value pair into a comment according to the placement guidelines in
+  the licensing rules documentation:
+    SPDX-License-Identifier: BSD-2-Clause
+License-Text:
+
+Copyright (c) <year> <owner> . All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.

Makefile.am

+ACLOCAL_AMFLAGS = -I m4 -I @VARNISHAPI_DATAROOTDIR@/aclocal
+
+DISTCHECK_CONFIGURE_FLAGS = RST2MAN=:
+
+SUBDIRS = src
+
+dist_doc_DATA = README.rst COPYING LICENSES/BSD-2-Clause LICENSES/LGPL-2.1
+
+EXTRA_DIST = INSTALL.rst
+
+coverage:
+	$(MAKE) $(AM_MAKEFLAGS) -C src coverage

bootstrap

+#!/bin/sh
+
+set -e
+set -u
+
+WORK_DIR=$(pwd)
+ROOT_DIR=$(dirname "$0")
+
+cd "$ROOT_DIR"
+
+if ! command -v libtoolize >/dev/null
+then
+	echo "libtoolize: command not found, falling back to glibtoolize" >&2
+	alias libtoolize=glibtoolize
+fi
+
+mkdir -p m4
+aclocal
+libtoolize --copy --force
+autoheader
+automake --add-missing --copy --foreign
+autoconf
+
+cd "$WORK_DIR"
+"$ROOT_DIR"/configure "$@"

configure.ac

+AC_PREREQ([2.68])
+AC_INIT([slash],[0.9])
+AC_CONFIG_MACRO_DIR([m4])
+AC_CONFIG_AUX_DIR([build-aux])
+AC_CONFIG_HEADERS([config.h])
+AC_USE_SYSTEM_EXTENSIONS
+
+AM_INIT_AUTOMAKE([1.12 -Wall -Werror foreign parallel-tests])
+AM_SILENT_RULES([yes])
+AM_PROG_AR
+AM_PROG_CC_C_O
+AX_PTHREAD(,[AC_MSG_ERROR([Could not configure pthreads support])])
+
+LIBS="$PTHREAD_LIBS $LIBS"
+CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+CC="$PTHREAD_CC"
+
+LT_PREREQ([2.2.6])
+LT_INIT([dlopen disable-static])
+
+AC_ARG_WITH([rst2man],
+	AS_HELP_STRING(
+		[--with-rst2man=PATH],
+		[Location of rst2man (auto)]),
+	[RST2MAN="$withval"],
+	[AC_CHECK_PROGS(RST2MAN, [rst2man rst2man.py], [])])
+
+AC_ARG_WITH([lcov],
+	AS_HELP_STRING(
+		[--with-lcov=PATH],
+		[Location of lcov to generate coverage data (auto)]),
+	[LCOV="$withval"],
+	[AC_CHECK_PROGS(LCOV, [lcov], [])])
+AM_CONDITIONAL(HAVE_LCOV, [test -n "$LCOV"])
+
+AC_ARG_WITH([genhtml],
+	AS_HELP_STRING(
+		[--with-genhtml=PATH],
+		[Location of genhtml to generate coverage reports (auto)]),
+	[GENHTML="$withval"],
+	[AC_CHECK_PROGS(GENHTML, [genhtml], [])])
+AM_CONDITIONAL(HAVE_GENHTML, [test -n "$GENHTML"])
+
+VARNISH_PREREQ([7.2.0])
+VARNISH_VMODS([slash])
+VARNISH_COUNTERS([slash])
+VARNISH_UTILITIES([slashmap])
+
+AC_ARG_VAR([VARNISHSRC], [path to Varnish source])
+if test "x$VARNISHSRC" = x; then
+	AC_MSG_FAILURE([Need VARNISHSRC])
+fi
+VARNISHSRC_CFLAGS="$VARNISHAPI_CFLAGS \
+	-I$VARNISHSRC/bin/varnishd \
+	-I$VARNISHSRC/lib/libvsc"
+AC_SUBST([VARNISHSRC_CFLAGS])
+
+AC_CHECK_HEADERS([stdatomic.h atomic.h])
+
+AC_CHECK_HEADERS([linux/mman.h linux/fs.h])
+
+AC_CHECK_HEADERS([sys/dkio.h])
+
+AC_ARG_ENABLE([uring],
+  [AS_HELP_STRING([--disable-uring],
+    [disable uring support])],
+  [],
+  [enable_uring=yes])
+
+AS_IF([test "x$enable_uring" != xno],
+  [AC_CHECK_HEADERS([liburing.h])],
+  [ac_cv_header_liburing_h=no])
+
+AC_ARG_ENABLE([asynch],
+  [AS_HELP_STRING([--disable-asynch],
+    [disable asynch support])],
+  [],
+  [enable_asynch=yes])
+
+AS_IF([test "x$enable_asynch" != xno],
+  [AC_CHECK_HEADERS([sys/asynch.h])],
+  [ac_cv_header_sys_asynch_h=no])
+
+AM_CONDITIONAL(HAVE_URING,[test "x$ac_cv_header_liburing_h" != "xno"])
+AM_CONDITIONAL(HAVE_ASYNCH,[test "x$ac_cv_header_sys_asynch_h" != "xno"])
+
+AC_CHECK_FUNCS([fallocate])
+
+PKG_CHECK_MODULES([XXHASH], [libxxhash], [], [true])
+# avoiding the fruitless RPATH debate for now
+if ! echo "$pkg_cv_XXHASH_LIBS" | grep -- "-R" ; then
+    tmp=$(echo "$pkg_cv_XXHASH_LIBS" | grep -Po '(?<=-L)\S+')
+    if test -n "${tmp}" ; then
+	XXHASH_LIBS="${pkg_cv_XXHASH_LIBS} -R${tmp}"
+    fi
+fi
+AC_CHECK_HEADERS([xxhash.h])
+
+## BEGIN from varnish-cache
+# --enable-stack-protector XXX remove -all
+AC_ARG_ENABLE(stack-protector,
+       AS_HELP_STRING([--enable-stack-protector],[enable stack protector (default is YES)]),
+       [],
+       [enable_stack_protector=yes])
+
+if test "x$enable_stack_protector" != "xno"; then
+	AX_CHECK_COMPILE_FLAG([-fstack-protector-all],
+		AX_CHECK_LINK_FLAG([-fstack-protector-all],
+			[CFLAGS="${CFLAGS} -fstack-protector-all"], [], []),
+		[], [])
+fi
+
+PKG_CHECK_MODULES([CURSES], [ncursesw], [], [
+	PKG_CHECK_MODULES([CURSES], [ncurses], [], [
+		PKG_CHECK_MODULES([CURSES], [curses], [], [
+AX_WITH_CURSES
+if test "x$ax_cv_curses" != xyes; then
+	AC_MSG_ERROR([requires an X/Open-compatible Curses library])
+fi
+CURSES_LIBS="$CURSES_LIB"
+		])
+	])
+])
+AC_SUBST([CURSES_CFLAGS])
+AC_SUBST([CURSES_LIBS])
+
+save_CFLAGS="${CFLAGS}"
+CFLAGS="${CFLAGS} ${CURSES_CFLAGS}"
+AC_CHECK_HEADERS([ncursesw/curses.h ncursesw.h ncurses/curses.h ncurses.h curses.h])
+CFLAGS="${save_CFLAGS}"
+
+save_CFLAGS="${CFLAGS}"
+CFLAGS="${CFLAGS} ${VARNISHAPI_CFLAGS}"
+# varnish-cache compat with 7.2
+AC_CHECK_MEMBER([struct boc.fetched_so_far],
+[AC_DEFINE([BOC_FETCHED_SO_FAR], [fetched_so_far], [Name of the field])],
+[AC_DEFINE([BOC_FETCHED_SO_FAR], [len_so_far], [Name of the field])],
+[[#include <cache/cache.h>]])
+CFLAGS="${save_CFLAGS}"
+
+## END
+
+AC_CONFIG_FILES([
+	Makefile
+	src/Makefile
+	src/slashmap.rst
+])
+
+AC_OUTPUT
+
+AS_ECHO("
+	==== $PACKAGE_STRING ====
+
+	varnish:      $VARNISH_VERSION
+	prefix:       $prefix
+	vmoddir:      $vmoddir
+	vcldir:       $vcldir
+	pkgvcldir:    $pkgvcldir
+
+	compiler:     $CC
+	cflags:       $CFLAGS
+	ldflags:      $LDFLAGS
+
+	xxhash:       $ac_cv_header_xxhash_h
+	uring:        $ac_cv_header_liburing_h
+	aio:          $ac_cv_header_sys_asynch_h
+")

src/Makefile.am

+AM_CFLAGS = $(VARNISHAPI_CFLAGS) -fno-strict-aliasing
+FREEPAGE_CFLAGS = -DFREEPAGE_WHEN
+DEV_CFLAGS = -Wall -Werror
+## to compile all with witness
+#DEV_CFLAGS = -Wall -Werror -DBUDDY_WITNESS  -DBUDDY_WITNESS_BACKTRACE
+
+# Modules
+
+vmod_LTLIBRARIES = \
+	libvmod_slash.la
+
+# buddy libs
+
+buddy_sources = \
+	buddy_witness.h \
+	slashmap.h \
+	buddy.h \
+	buddy_util.h \
+	buddy.c \
+	bitsof.h \
+	bitf.h \
+	tbl/mmap_flags.h \
+	foreign/vmb.h
+
+noinst_LTLIBRARIES = \
+	libbuddy.la \
+	libbuddywhen.la \
+	libbuddywitness.la
+
+libbuddy_la_CFLAGS = $(AM_CFLAGS) $(DEV_CFLAGS)
+libbuddywhen_la_CFLAGS = $(libbuddy_la_CFLAGS) $(FREEPAGE_CFLAGS)
+libbuddywitness_la_CFLAGS = $(libbuddy_la_CFLAGS) -DBUDDY_WITNESS
+
+libbuddy_la_SOURCES = $(buddy_sources)
+libbuddywhen_la_SOURCES = $(libbuddy_la_SOURCES)
+libbuddywitness_la_SOURCES = $(libbuddy_la_SOURCES)
+
+# vmod
+
+# freepage is only used for buddy_storage, not for fellow_storage
+noinst_LTLIBRARIES += \
+	libbuddy_storage.la
+
+libbuddy_storage_la_CFLAGS = \
+    $(AM_CFLAGS) $(FREEPAGE_CFLAGS) $(VARNISHSRC_CFLAGS) $(DEV_CFLAGS)
+libbuddy_storage_la_SOURCES = \
+	buddy_storage.c \
+	tbl/buddy_tunables.h \
+	buddy_tune.h \
+	buddy_tune.c
+
+libvmod_slash_la_CFLAGS = $(AM_CFLAGS) $(VARNISHSRC_CFLAGS) $(DEV_CFLAGS)
+libvmod_slash_la_LDFLAGS = $(VMOD_LDFLAGS)
+libvmod_slash_la_SOURCES = \
+	vmod_slash.c \
+	vmod_slash_loadmasters.c \
+	fellow_storage.c \
+	fellow_storage_deref.h \
+	fellow_cache_storage.h \
+	fellow_stash.h \
+	fellow_log_storage.h
+libvmod_slash_la_LIBADD = \
+	libbuddy_storage.la \
+	libbuddywhen.la \
+	libfellow.la
+
+# XXX revisit
+# linked to libfellow.la:
+#	libbuddy.la
+
+nodist_libvmod_slash_la_SOURCES = \
+	vcc_slash_if.c \
+	vcc_slash_if.h
+
+vmod_slash.c: vcc_slash_if.h
+
+@BUILD_VMOD_SLASH@
+
+# Utilities
+
+bin_PROGRAMS = \
+	slashmap \
+	buddy_test \
+	buddy_test_when
+
+slashmap_LDFLAGS = $(VARNISHAPI_LIBS) @CURSES_LIBS@
+slashmap_CFLAGS = $(AM_CFLAGS) @CURSES_CFLAGS@ $(DEV_CFLAGS)
+slashmap_SOURCES = \
+	slashmap.c \
+	slashmap_options.h \
+	slashmap.h \
+	pow2_units.c \
+	pow2_units.h \
+	bitsof.h \
+	bitf.h \
+	foreign/vcurses.h
+
+buddy_test_LDFLAGS = $(VARNISHAPI_LIBS)
+buddy_test_CFLAGS = \
+	$(AM_CFLAGS) -DDEBUG -DTEST_DRIVER $(DEV_CFLAGS)
+buddy_test_SOURCES = \
+	$(buddy_sources)
+
+buddy_test_witness_LDFLAGS = $(VARNISHAPI_LIBS)
+buddy_test_witness_CFLAGS = \
+	$(AM_CFLAGS) -DDEBUG -DTEST_DRIVER -DBUDDY_WITNESS $(DEV_CFLAGS)
+buddy_test_witness_SOURCES = \
+	$(buddy_sources)
+
+buddy_test_when_LDFLAGS = $(VARNISHAPI_LIBS)
+buddy_test_when_CFLAGS = \
+	$(AM_CFLAGS) -DDEBUG -DTEST_DRIVER $(FREEPAGE_CFLAGS) $(DEV_CFLAGS)
+buddy_test_when_SOURCES = \
+	$(buddy_sources)
+
+noinst_PROGRAMS = \
+	buddy_test \
+	buddy_test_witness \
+	buddy_test_when
+
+# Test suite
+
+AM_TESTS_ENVIRONMENT = \
+	PATH="$(abs_builddir):$(VARNISH_TEST_PATH):$(PATH)" \
+	LD_LIBRARY_PATH="$(VARNISH_LIBRARY_PATH)"
+TEST_EXTENSIONS = .vtc
+VTC_LOG_COMPILER = varnishtest -l -v -b 10m
+AM_VTC_LOG_FLAGS = \
+	-D libvmod_slash="$(abs_builddir)/.libs/libvmod_slash.so" \
+	-p vcl_path="$(abs_top_srcdir)/vcl:$(VARNISHAPI_VCLDIR)" \
+	-p vmod_path="$(abs_builddir)/.libs:$(vmoddir):$(VARNISHAPI_VMODDIR)"
+
+TESTS = \
+	buddy_test \
+	buddy_test_witness \
+	buddy_test_when \
+	vtc/buddy_vcl.vtc \
+	vtc/buddy_global.vtc \
+	vtc/buddy_edgecases.vtc \
+	vtc/buddy_c00062.vtc \
+	vtc/buddy_c00075.vtc \
+	vtc/buddy_c00097.vtc \
+	vtc/buddy_t02005.vtc \
+	vtc/fellow_vcl.vtc \
+	vtc/fellow_global.vtc \
+	vtc/fellow_global_shared.vtc \
+	vtc/fellow_coverage.vtc \
+	vtc/fellow_t02005.vtc \
+	vtc/vut_slashmap.vtc \
+	vtc/loadmasters.vtc
+
+fellow_state_tables = \
+	tbl/fco_states.h \
+	tbl/fcs_states.h \
+	tbl/fco_transition.h \
+	tbl/fcs_transition.h
+
+fellow_sources = \
+	pow2_units.c \
+	pow2_units.h \
+	buddy.h \
+	buddy_util.h \
+	compiler.h \
+	$(fellow_state_tables) \
+	fellow_debug.h \
+	fellow_io_backend.h \
+	fellow_io.h \
+	fellow_log.c \
+	fellow_log.h \
+	fellow_log_iter_out.h \
+	fellow_log_dle_chg.h \
+	fellow_regionlist.h \
+	fellow_sha256.h \
+	fellow_sha256.c \
+	fellow_cache.h \
+	fellow_cache.c \
+	tbl/fellow_tunables.h \
+	tbl/dle.h \
+	fellow_tune.h \
+	fellow_tune.c \
+	fellow_hash.c \
+	fellow_hash.h \
+	fellow_hashes.h \
+	fellow_diag.h \
+	fellow_errhandling.h \
+	fellow_task.h \
+	fellow_testenv.h \
+	fellow_testenv.c \
+	include/foreign/vend.h \
+	include/foreign/ban.h
+
+noinst_LTLIBRARIES += \
+	libfellow.la \
+	libfellowwitness.la
+
+libfellow_libadd = \
+	$(VARNISHSRC)/lib/libvarnish/libvarnish.la $(XXHASH_LIBS)
+
+io_ioctl_sources = \
+	fellow_io_ioctl.c \
+	fellow_io_ioctl.h
+
+fellow_sources += $(io_ioctl_sources)
+
+if HAVE_URING
+fellow_sources += fellow_io_uring.c
+libfellow_libadd += -luring
+else
+if HAVE_ASYNCH
+fellow_sources += fellow_io_aio.c
+else
+fellow_sources += fellow_io_threads.c
+endif
+endif
+
+libfellow_la_CFLAGS = $(AM_CFLAGS) $(DEV_CFLAGS) $(XXHASH_CFLAGS)
+libfellowwitness_la_CFLAGS = $(libfellow_la_CFLAGS) \
+	-DBUDDY_WITNESS -DDEBUG
+
+libfellow_la_SOURCES = $(fellow_sources)
+libfellowwitness_la_SOURCES = $(libfellow_la_SOURCES)
+
+libfellow_la_LIBADD = $(libfellow_libadd) libbuddy.la
+libfellowwitness_la_LIBADD = $(libfellow_libadd) libbuddywitness.la
+
+############################################################
+## log_dbg: output the log contents
+
+fellow_log_dbg_CFLAGS = $(AM_CFLAGS) $(DEV_CFLAGS) $(XXHASH_CFLAGS) \
+	-DDEBUG -DFDBGL=2
+fellow_log_dbg_LDADD = $(libfellow_libadd) libbuddy.la
+
+# fellow sources without the following:
+#	fellow_cache.h \
+#	fellow_cache.c \
+	pow2_units.c \
+	pow2_units.h \
+#
+
+fellow_log_dbg_SOURCES = fellow_log_dbg.c \
+	buddy.h \
+	buddy_util.h \
+	$(fellow_state_tables) \
+	fellow_debug.h \
+	fellow_io_backend.h \
+	fellow_io.h \
+	fellow_log.c \
+	fellow_log.h \
+	fellow_log_iter_out.h \
+	fellow_log_dle_chg.h \
+	fellow_regionlist.h \
+	fellow_sha256.h \
+	fellow_sha256.c \
+	tbl/fellow_tunables.h \
+	tbl/dle.h \
+	fellow_tune.h \
+	fellow_tune.c \
+	fellow_hash.c \
+	fellow_hash.h \
+	fellow_hashes.h \
+	fellow_diag.h \
+	fellow_errhandling.h \
+	fellow_task.h \
+	fellow_testenv.h \
+	fellow_testenv.c \
+	include/foreign/vend.h
+
+fellow_log_dbg_SOURCES += $(io_ioctl_sources)
+
+# XXX duplication
+if HAVE_URING
+fellow_log_dbg_SOURCES += fellow_io_uring.c
+fellow_log_dbg_LDADD += -luring
+else
+if HAVE_ASYNCH
+fellow_log_dbg_SOURCES += fellow_io_aio.c
+else
+fellow_log_dbg_SOURCES += fellow_io_threads.c
+endif
+endif
+
+############################################################
+## test programs
+
+fellow_log_test_ndebug_LDADD = libfellow.la
+fellow_log_test_ndebug_CFLAGS = $(AM_CFLAGS) $(DEV_CFLAGS) $(XXHASH_CFLAGS) -DTEST_DRIVER
+fellow_log_test_ndebug_SOURCES = fellow_log_test.c
+
+fellow_log_test_LDFLAGS = $(fellow_log_test_ndebug_LDFLAGS)
+fellow_log_test_LDADD = libfellowwitness.la
+fellow_log_test_CFLAGS = $(fellow_log_test_ndebug_CFLAGS) \
+	-DDEBUG -DBUDDY_WITNESS
+fellow_log_test_SOURCES = $(fellow_log_test_ndebug_SOURCES)
+
+# XXX EXTRA .c FILE
+fellow_cache_test_LDFLAGS = $(fellow_log_test_ndebug_LDFLAGS)
+fellow_cache_test_LDADD = libfellowwitness.la
+fellow_cache_test_CFLAGS = $(fellow_log_test_ndebug_CFLAGS) \
+	-DDEBUG -DBUDDY_WITNESS
+fellow_cache_test_SOURCES = fellow_cache.c
+
+noinst_PROGRAMS += \
+	fellow_log_dbg \
+	fellow_log_test_ndebug \
+	fellow_log_test \
+	fellow_cache_test
+
+TESTS += \
+	fellow_log_test_ndebug \
+	fellow_log_test \
+	fellow_cache_test
+
+# Code coverage
+
+gcov: clean
+	$(AM_V_at)$(MAKE) $(AM_MAKEFLAGS) CC=gcc \
+		CFLAGS="${AM_CFLAGS} --coverage -fno-inline -g -O0" check
+
+# Set QUIET=-q for non-verbose builds, otherwise set to empty.
+QUIET_0 = -q
+QUIET_ = $(QUIET_@AM_DEFAULT_V@)
+QUIET = $(QUIET_@AM_V@)
+
+coverage/lcov.info: gcov
+if HAVE_LCOV
+	$(AM_V_at)@mkdir $(builddir)/coverage
+	$(AM_V_GEN) $(LCOV) $(QUIET) -c -d . -o  $(builddir)/coverage/lcov.info
+else
+	@echo "================================================="
+	@echo "You need lcov installed to generate coverage data"
+	@echo "================================================="
+	@false
+endif
+
+coverage: coverage/lcov.info
+if HAVE_GENHTML
+	$(AM_V_GEN) $(GENHTML) $(QUIET) $(builddir)/coverage/lcov.info \
+		-o  $(builddir)/coverage
+else
+	@echo "======================================================="
+	@echo "You need genhtml installed to generate coverage reports"
+	@echo "======================================================="
+	@false
+endif
+
+CLEANFILES = \
+	$(builddir)/*.gcda \
+	$(builddir)/*.gcno
+
+clean-local:
+	@rm -rf $(builddir)/coverage
+
+# VSC
+
+.vsc.c:
+	$(VSCTOOL) -c $<
+
+.vsc.h:
+	$(VSCTOOL) -h $<
+
+.vsc.rst:
+	$(VSCTOOL) -r $< >$@.tmp
+	@cat $@.tmp >$@
+	@rm -f $@.tmp
+
+EXTRA_DIST = \
+	VSC_buddy.vsc \
+	VSC_fellow.vsc
+
+VSC_SOURCES = \
+	VSC_buddy.c \
+	VSC_buddy.h \
+	VSC_fellow.c \
+	VSC_fellow.h
+
+VSC_RST = \
+	VSC_buddy.rst \
+	VSC_fellow.rst
+
+slash-counters.7: $(VSC_RST)
+
+nodist_libvmod_slash_la_SOURCES += $(VSC_SOURCES)
+
+buddy_storage.c: VSC_buddy.h
+
+fellow_storage.c: VSC_fellow.h
+
+# DOT
+
+fcs_states.dot: $(fellow_state_tables)
+
+# cat instead of mv: graphviz does not update for new file
+.doth.dot:
+	@rm -f $@.h
+	@ln $< $@.h || cp $< $@.h
+	$(AM_V_GEN) ( \
+	  $(CPP) -I$(srcdir) $@.h | sed '/^#/ d; s:\\n *:\
+:g') >$@.tmp
+	@rm -f $@.h
+	@cat $@.tmp >$@
+	@rm -f $@.tmp
+
+
+# Documentation
+
+dist_doc_DATA = \
+	vmod_slash.vcc
+
+dist_man_MANS = \
+	vmod_slash.3 \
+	slashmap.1 \
+	slash-counters.7
+
+@GENERATE_SLASHMAP_DOCS@
+
+.rst.1:
+	$(AM_V_GEN) $(RST2MAN) $< $@
+
+.rst.7:
+	$(AM_V_GEN) $(RST2MAN) $< $@
+
+.PHONY: flint
+
+# XXX slashmap should be flexelinted when time, for now it does not matter
+# XXX TODO flexelint fellow_io_*
+flint:
+	flexelint $(VARNISHSRC_CFLAGS) -I .. flint.lnt \
+		`ls *.c | grep -vE 'fellow_io_aio|fellow_io_threads|fellow_log_test.c|slashmap.c'`

src/VSC_buddy.vsc

+..
+	SPDX-License-Identifier: LGPL-2.1-only
+	Copyright 2023 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+	Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+	This library is free software; you can redistribute it and/or
+	modify it under the terms of the GNU Lesser General Public License
+	as published by the Free Software Foundation; either version 2.1 of
+	the License, or (at your option) any later version.
+ *
+	This library is distributed in the hope that it will be useful, but
+	WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+	Lesser General Public License for more details.
+ *
+	You should have received a copy of the GNU Lesser General Public
+	License along with this library; if not, write to the Free Software
+	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+	02110-1301 USA Also add information on how to contact you by
+	electronic and paper mail.
+
+.. varnish_vsc_begin::	buddy
+	:oneliner:	buddy Stevedore Counters (SLASH/ stevedores)
+	:order:		70
+
+.. varnish_vsc:: c_req
+	:type:	counter
+	:level:	info
+	:oneliner:	Allocator requests
+
+	Number of times the storage has been asked to provide a storage segment.
+
+.. varnish_vsc:: c_fail
+	:type:	counter
+	:level:	info
+	:oneliner:	Allocator failures
+
+	Number of times the storage has failed to provide a storage segment.
+
+.. varnish_vsc:: c_bytes
+	:type:	counter
+	:level:	info
+	:format: bytes
+	:oneliner:	Bytes allocated
+
+	Number of total bytes allocated by this storage.
+
+.. varnish_vsc:: c_freed
+	:type:	counter
+	:level:	info
+	:format: bytes
+	:oneliner:	Bytes freed
+
+	Number of total bytes returned to this storage.
+
+.. varnish_vsc:: g_alloc
+	:type:	gauge
+	:level:	info
+	:oneliner:	Allocations outstanding
+
+	Number of storage allocations outstanding.
+
+.. varnish_vsc:: g_bytes
+	:type:	gauge
+	:level:	info
+	:format: bytes
+	:oneliner:	Bytes outstanding
+
+	Number of bytes allocated from the storage.
+
+	Note: This number is only approximate
+
+.. varnish_vsc:: g_space
+	:type:	gauge
+	:level:	info
+	:format: bytes
+	:oneliner:	Bytes available
+
+	Number of bytes left in the storage.
+
+	Note: This number is only approximate
+
+.. varnish_vsc_end::	buddy

src/VSC_fellow.vsc

+..
+	SPDX-License-Identifier: LGPL-2.1-only
+	Copyright 2023 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+	Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+	This library is free software; you can redistribute it and/or
+	modify it under the terms of the GNU Lesser General Public License
+	as published by the Free Software Foundation; either version 2.1 of
+	the License, or (at your option) any later version.
+ *
+	This library is distributed in the hope that it will be useful, but
+	WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+	Lesser General Public License for more details.
+ *
+	You should have received a copy of the GNU Lesser General Public
+	License along with this library; if not, write to the Free Software
+	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+	02110-1301 USA Also add information on how to contact you by
+	electronic and paper mail.
+
+.. varnish_vsc_begin::	fellow
+	:oneliner:	fellow Stevedore Counters (SLASH/ stevedores)
+	:order:		70
+
+.. varnish_vsc:: c_allocobj
+	:type:	counter
+	:level:	info
+	:oneliner:	Requests to allocate an object
+
+	Number of times the storage has been asked to create an object
+
+.. varnish_vsc:: c_allocobj_fail
+	:type:	counter
+	:level:	info
+	:oneliner:	Object creation failures
+
+	Number of times the storage failed to create an object
+
+.. varnish_vsc:: c_dsk_obj_get_present
+	:type:	counter
+	:level:	info
+	:oneliner:	Access to a disk object which was already present
+
+	Number of times a memory pointer was already present for a disk object
+
+.. varnish_vsc:: c_dsk_obj_get_fail
+	:type:	counter
+	:level:	info
+	:oneliner:	Access to a disk object failed
+
+	Number of times access to a disk object failed
+
+.. varnish_vsc:: c_dsk_obj_get
+	:type:	counter
+	:level:	info
+	:oneliner:	Access to a disk object
+
+	Number of times a disk object (vampireobject) was read and turned
+	into a memory object (object)
+
+.. varnish_vsc:: c_dsk_obj_get_coalesce
+	:type:	counter
+	:level:	info
+	:oneliner:	Access to a disk object when already in progress
+
+	Number of times a disk object (vampireobject) was accessed and
+	a get operation was already in progress
+
+.. varnish_vsc:: c_mem_obj_free
+	:type:	counter
+	:level:	info
+	:oneliner:	Memory object free operations
+
+	Number of times a memory object was freed
+
+.. varnish_vsc:: c_dsk_obj_free_thin
+	:type:	counter
+	:level:	info
+	:oneliner:	Disk object free operations with thin deletion
+
+	Number of times a disk object was freed by logging a thin deletion
+	request to be executed with the next log rewrite.
+
+.. varnish_vsc:: c_dsk_obj_free_get
+	:type:	counter
+	:level:	info
+	:oneliner:	Disk object free operations with disk read
+
+	Number of times a disk object was freed by reading the object.
+	Each operation also adds one to one of the c_dsk_obj_get_*
+	counters.
+
+.. varnish_vsc:: c_mem_obj_mutate
+	:type:	counter
+	:level:	info
+	:oneliner:	Memory object evictions
+
+	Number of times an object was evicted from memory and turned
+	into a disk object (vampireobject). The term mutate was chosen
+	in favor of "vampirization" or similar.
+
+.. varnish_vsc:: g_mem_bytes
+	:type:	gauge
+	:level:	info
+	:format: bytes
+	:oneliner:	Memory Bytes outstanding
+
+	Number of bytes allocated from memory
+
+	Note: This number is only approximate
+
+.. varnish_vsc:: g_mem_space
+	:type:	gauge
+	:level:	info
+	:format: bytes
+	:oneliner:	Memory Bytes available
+
+	Number of bytes left in memory
+
+	Note: This number is only approximate
+
+.. varnish_vsc:: g_dsk_bytes
+	:type:	gauge
+	:level:	info
+	:format: bytes
+	:oneliner:	Disk Bytes outstanding
+
+	Number of bytes allocated from disk
+
+	Note: This number is only approximate
+
+.. varnish_vsc:: g_dsk_space
+	:type:	gauge
+	:level:	info
+	:format: bytes
+	:oneliner:	Disk Bytes available
+
+	Number of bytes left in disk
+
+	Note: This number is only approximate
+
+.. varnish_vsc_end::	fellow

src/bitf.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+#include <stdint.h>
+#include <unistd.h>
+#include <string.h>
+#include <assert.h>
+
+#include "bitsof.h"
+
+/*
+ * bitf_index() / (struct bitf).idxoff:
+ *
+ * We accelerate lookup in large bitfields with an index which has a bit set IFF
+ * a word is non-zero
+ *
+ * As each index is recursively indexed also, we effectively reduce lookup time
+ * to log(size), equaling that of a btree without the memory overhead
+ *
+ * idxoff is relative to the address of the bitfield itself to support
+ * relocation
+ */
+
+struct bitf {
+	unsigned	magic;
+#define BITF_MAGIC	0x91ebd5ff
+	size_t		nbits;
+	size_t		nset;	// count of set bits
+	size_t		idxoff; // distance to next index or 0 if none
+	void		*extra;
+	bitf_word_t	bits[];
+};
+
+#define wsz sizeof(bitf_word_t)
+#define wbits (wsz * 8)
+#define index_thr (wbits * 8)
+#define bitf_words(bits) ((((bits + 7) / 8) + wsz - 1) / wsz)
+#define bitf_sz1(bits) (sizeof(struct bitf) + bitf_words(bits) * wsz)
+
+static inline size_t
+bitf_sz(size_t bits)
+{
+	size_t sz;
+
+	sz = bitf_sz1(bits);
+	while (bits > index_thr) {
+		bits /= wbits;
+		bits++;
+		sz += bitf_sz1(bits);
+	}
+	return (sz);
+}
+
+// pointer to word from bits
+#define bitf_word(bitf, bit)						\
+	(assert((bitf)->magic == BITF_MAGIC),				\
+	 assert((bit) < (bitf)->nbits),					\
+	 &(bitf)->bits[bit / wbits])
+
+// set bit in word
+#define bitf_bit(bit) ((bitf_word_t)1 << (bit % wbits))
+
+static inline struct bitf *
+bitf_init(void *p, size_t bits, size_t space)
+{
+	struct bitf *bitf;
+	size_t sz = bitf_sz1(bits);
+	char *pp;
+
+	assert(space >= sz);
+
+	memset(p, 0, sz);
+	bitf = p;
+	bitf->magic = BITF_MAGIC;
+	bitf->nbits = bits;
+
+	if (bits > index_thr) {
+		bits /= wbits;
+		bits++;
+		pp = p;
+		pp += sz;
+		space -= sz;
+		bitf->idxoff = sz;
+		p = bitf_init(pp, bits, space);
+		assert(p);
+	}
+
+	return (bitf);
+}
+
+static inline struct bitf *
+bitf_indexl(struct bitf *bitf)
+{
+	assert(bitf->idxoff);
+	//lint --e(826)
+	return ((struct bitf *)((char *)bitf + bitf->idxoff));
+}
+
+static inline const struct bitf *
+bitf_indexr(const struct bitf *bitf)
+{
+	assert(bitf->idxoff);
+	//lint --e(826)
+	return ((const struct bitf *)((const char *)bitf + bitf->idxoff));
+}
+
+// return if bit was set (1: was zero, 0: was already one)
+static inline unsigned
+bitf_set(struct bitf *bitf, size_t bit)
+{
+	bitf_word_t *w = bitf_word(bitf, bit);
+	const bitf_word_t b = bitf_bit(bit);
+	unsigned c, o;
+
+	if (bitf->idxoff && !*w) {
+		c = bitf_set(bitf_indexl(bitf), bit / wbits);
+		assert(c);
+	}
+
+	o = !(*w & b);
+	*w |= b;
+	bitf->nset += o;
+	return (o);
+}
+
+// number of bits set
+static inline size_t
+bitf_nset(const struct bitf *bitf)
+{
+	CHECK_OBJ_NOTNULL(bitf, BITF_MAGIC);
+	return (bitf->nset);
+}
+
+// number of bit set
+static inline size_t
+bitf_nbits(const struct bitf *bitf)
+{
+	CHECK_OBJ_NOTNULL(bitf, BITF_MAGIC);
+	return (bitf->nbits);
+}
+
+// return if bit was cleared (1: was one, 0: was already zero)
+static inline unsigned
+bitf_clr(struct bitf *bitf, size_t bit)
+{
+	bitf_word_t *w = bitf_word(bitf, bit);
+	const bitf_word_t b = bitf_bit(bit);
+	unsigned c, o;
+
+	o = !!(*w & b);
+	*w &= ~b;
+	bitf->nset -= o;
+
+	if (bitf->idxoff && !*w && o) {
+		c = bitf_clr(bitf_indexl(bitf), bit / wbits);
+		assert(c);
+	}
+
+	return (o);
+}
+
+static inline int
+bitf_get(const struct bitf *bitf, size_t bit)
+{
+	const bitf_word_t *w = bitf_word(bitf, bit);
+
+	return !!(*w & bitf_bit(bit));
+}
+
+/* return bit number PLUS ONE or 0 if none set */
+static inline size_t
+bitf_ffs(const struct bitf *bitf)
+{
+	const bitf_word_t *w = bitf->bits;
+	const size_t l = bitf_words(bitf->nbits);
+	size_t u = 0;
+	int t;
+
+	if (bitf->idxoff) {
+		u = bitf_ffs(bitf_indexr(bitf));
+		if (u == 0)
+			return (0);
+		u--;
+	}
+
+	for (w += u; u < l; u++, w++) {
+		if (*w == 0)
+			continue;
+		t = ffsszt(*w);
+		assert(t > 0);
+		return (u * wbits + (unsigned)t);
+	}
+
+	return (0);
+}
+
+/* return bit number PLUS ONE or 0 if none set
+ * at or after a start bit position
+ *
+ * should work approximately correct for dirty/unlocked/concurrent
+ * reads
+ */
+
+static inline size_t
+bitf_ffs_from(const struct bitf *bitf, size_t start)
+{
+	const size_t l = bitf_words(bitf->nbits);
+	size_t s, u, b;
+	int t;
+	const bitf_word_t *w = bitf->bits;
+	bitf_word_t ww;
+
+	s = start / wbits;
+	b = start % wbits;
+
+	if (bitf->idxoff) {
+		u = bitf_ffs_from(bitf_indexr(bitf), s);
+		if (u == 0)
+			return (0);
+		u--;
+		if (u > s) {
+			s = u;
+			b = 0;
+		} else
+			assert(u == s);
+	}
+
+	for (u = s, w += u; u < l; u++, w++) {
+		ww = *w;
+		if (ww == 0)
+			continue;
+		t = ffsszt(ww);
+		// DIRTY assert(t > 0);
+
+		if (u != s || (t > 0 && (unsigned)t > b))
+			return (u * wbits + (unsigned)t);
+
+		/* in our word, the first set bit is before the start
+		 * we clear all bits bits before the start and check
+		 * if another one is set
+		 */
+		AN(b);
+		ww &= ~(((bitf_word_t)1 << b) - 1);
+		t = ffsszt(ww);
+		if (t > 0)
+			return (u * wbits + (unsigned)t);
+	}
+
+	return (0);
+}
+
+/*
+ * unless *cache is reset to SIZE_MAX, must be called with increasing start
+ * values only
+ */
+static inline size_t
+bitf_ffs_from_cached(const struct bitf *bitf, size_t *cache, size_t start)
+{
+	size_t b;
+
+	AN(cache);
+	b = *cache;
+	if (b == 0 || (b > start && b < SIZE_MAX))
+		return (b);
+	b = bitf_ffs_from(bitf, start);
+	*cache = b;
+	return (b);
+}

src/bitsof.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+#ifndef BITSOF_H
+#define BITSOF_H
+// XXX autoconf to check for builtin, else use ffsl ffsll
+#if SIZE_MAX == 0xffffffffffffffff
+#define clzszt(v) __builtin_clzll(v)
+#define ffsszt(v) __builtin_ffsll(v)
+typedef unsigned long long bitf_word_t;
+#elif SIZE_MAX == 0xffffffff
+#define clzszt(v) __builtin_clzl(v)
+#define ffsszt(v) __builtin_ffsl(v)
+typedef unsigned long bitf_word_t;
+#else
+#error unsupported size_t
+#endif
+
+#define bitsof(v) (sizeof(v) * 8 - (unsigned)clzszt(v))
+#endif

src/buddy_storage.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022,2023 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+struct stevedore *
+sbu_new(const char *id, size_t *sz, size_t *min);
+void sbu_fini(struct stevedore **);
+struct stvbu_tune;
+void
+sbu_tune_get(const struct stevedore *stv, struct stvbu_tune *tune);
+const char *
+sbu_tune_apply(const struct stevedore *stv, const struct stvbu_tune *tuna);
+int sbu_is(VCL_STEVEDORE);
+void sbu_as_transient(struct stevedore *);

src/buddy_tune.c

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2023 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+#include "config.h"
+
+#include <assert.h>
+#include <string.h>
+#include <limits.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "miniobj.h"
+
+#include "buddy_tune.h"
+#include "buddy_util.h"
+
+/* initialize with sane defaults */
+const char *
+stvbu_tune_init(struct stvbu_tune *tune, size_t sz)
+{
+	INIT_OBJ(tune, STVBU_TUNE_MAGIC);
+
+//lint -e773,
+#define TUNE(t, n, d, min, max)			\
+	tune->n = (d)
+#include "tbl/buddy_tunables.h"
+//lint +e773,
+	tune->sz = sz;
+	return (stvbu_tune_check(tune));
+}
+
+// XXX VSL for warnigs
+
+const char *
+stvbu_tune_check(struct stvbu_tune *tune)
+{
+	unsigned l;
+	size_t sz;
+
+	l = log2down(tune->sz) - 4;
+	if (tune->chunk_exponent > l) {
+		fprintf(stderr,"buddy: chunk_exponent limited to %u "
+		    "(less than 1/16 of memory size)\n", l);
+
+		tune->reserve_chunks <<= (tune->chunk_exponent - l);
+		tune->chunk_exponent = l;
+	}
+
+	sz = tune->sz >> (tune->chunk_exponent - 1);
+	assert(sz <= UINT_MAX);
+	l = (unsigned)sz;
+	if (tune->reserve_chunks > l) {
+		fprintf(stderr,"buddy: reserve_chunks limited to %u "
+		    "(less than 1/8 of memory size)\n", l);
+		tune->reserve_chunks = l;
+	}
+
+//lint --e{685,568} misc const comparisons
+#define TUNE(t, n, d, min, max)						\
+	if (tune->n < (min))						\
+		return ("Value of " #n " is too small, minimum is " #min); \
+	if (tune->n > (max))						\
+		return ("Value of " #n " is too big, maximum is " #max); \
+
+#include "tbl/buddy_tunables.h"
+	return (NULL);
+}

src/buddy_tune.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2023 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+struct stvbu_tune {
+	unsigned		magic;
+#define STVBU_TUNE_MAGIC	0x65755427
+
+#define TUNE(t, n, d, min, max)			\
+	t	n
+#include "tbl/buddy_tunables.h"
+
+	size_t			sz;
+};
+
+const char *
+stvbu_tune_init(struct stvbu_tune *tune, size_t sz);
+const char *
+stvbu_tune_check(struct stvbu_tune *tune);

src/buddy_util.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+#include "bitsof.h"
+
+/*
+ * min is the number of bits of the minimum allocation
+ */
+static inline size_t
+rup_min(size_t size, unsigned minbits)
+{
+	size_t min;
+
+	min = (size_t)1 << minbits;
+	min--;
+	size += min;
+	size &= ~min;
+	return (size);
+}
+static inline size_t
+rdown_min(size_t size, unsigned minbits)
+{
+	size_t min;
+
+	min = (size_t)1 << minbits;
+	min--;
+	return (size & ~min);
+}
+
+/* next log 2 of sz */
+static inline unsigned
+log2up(size_t sz)
+{
+
+	sz--;
+	sz = bitsof(sz);
+	assert(sz > 0);
+	assert(sz <= UINT_MAX);
+	return ((unsigned) sz);
+}
+
+/* prev log 2 of sz */
+static inline unsigned
+log2down(size_t sz)
+{
+
+	sz = bitsof(sz) - 1;
+	assert(sz <= UINT_MAX);
+	return ((unsigned) sz);
+}

src/compiler.h

+// from linux
+#define likely(x)      __builtin_expect(!!(x), 1)
+//#define unlikely(x)    __builtin_expect(!!(x), 0)

src/debug.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+#ifdef DEBUG
+#include <stdio.h>
+#define _DBG(f, x, ...) fprintf(stderr, "dbg %s " x "\n", __func__, __VA_ARGS__)
+#define DBG(x, ...) _DBG(__func__, x,__VA_ARGS__)
+#else
+#define DBG(x, ...) (void)0
+#endif

src/fcs_states.doth

+/* -*- c -*- */
+
+#define FCS(x) FCS_ ## x
+#define FCO(x) FCO_ ## x
+#define FCOSD(x, s, c, lru, fdb, mem, dsk)		\
+x ## _ ## s
+//x ## _ ## s [label=#x + "_" + #s + "\l" + c]\n
+
+digraph fco_fcs_state {
+subgraph xcluster_fco {
+#include "tbl/fco_states.h"
+#define FCOT(f, t, c)	\
+FCO_ ## f -> FCO_ ## t
+//FCO_ ## f -> FCO_ ## t [label=c]
+#include "tbl/fco_transition.h"
+}
+subgraph xcluster_fcs {
+#include "tbl/fcs_states.h"
+#define FCST(f, t, c)	\
+FCS_ ## f -> FCS_ ## t
+//FCS_ ## f -> FCS_ ## t [label=c]
+#include "tbl/fcs_transition.h"
+}
+}

src/fellow_cache_storage.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022,2023 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+void fellow_cache_obj_evict_mutate(struct fellow_cache *fc,
+    struct fellow_cache_obj *fco);
+
+void stvfe_oc_log_removed(struct objcore *oc);
+void stvfe_oc_log_submitted(struct objcore *oc);
+void stvfe_oc_dle_obj(struct objcore *oc, struct fellow_dle *e);
+
+int stvfe_mutate(struct worker *wrk, struct objcore *oc);
+void stvfe_sumstat(struct worker *wrk); // wraps Pool_Sumstat(wrk);

src/fellow_diag.h

+/*-
+ * SPDX-License-Identifier: LGPL-2.1-only
+ * Copyright 2022 UPLEX Nils Goroll Systemoptimierung. All rights reserved.
+ * Author: Nils Goroll <nils.goroll@uplex.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA Also add information on how to contact you by
+ * electronic and paper mail.
+ */
+
+// v_printfike
+#if __GNUC_PREREQ__(2, 95) || defined(__INTEL_COMPILER)
+#  define fe_printflike_(f,a) __attribute__((format(printf, f, a)))
+#else
+#  define fe_printflike_(f,a)
+#endif
+
+typedef void fellow_diag_f(const char *fmt, ...) fe_printflike_(1, 2);