https://github.com/torvalds/linux
Tip revision: 4fe89d07dcc2804c8b562f6c7896a45643d34b2f authored by Linus Torvalds on 02 October 2022, 21:09:07 UTC
Linux 6.0
Linux 6.0
Tip revision: 4fe89d0
gen-atomic-instrumented.sh
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
ATOMICDIR=$(dirname $0)
. ${ATOMICDIR}/atomic-tbl.sh
#gen_param_check(meta, arg)
gen_param_check()
{
local meta="$1"; shift
local arg="$1"; shift
local type="${arg%%:*}"
local name="$(gen_param_name "${arg}")"
local rw="write"
case "${type#c}" in
i) return;;
esac
if [ ${type#c} != ${type} ]; then
# We don't write to constant parameters.
rw="read"
elif [ "${meta}" != "s" ]; then
# An atomic RMW: if this parameter is not a constant, and this atomic is
# not just a 's'tore, this parameter is both read from and written to.
rw="read_write"
fi
printf "\tinstrument_atomic_${rw}(${name}, sizeof(*${name}));\n"
}
#gen_params_checks(meta, arg...)
gen_params_checks()
{
local meta="$1"; shift
local order="$1"; shift
if [ "${order}" = "_release" ]; then
printf "\tkcsan_release();\n"
elif [ -z "${order}" ] && ! meta_in "$meta" "slv"; then
# RMW with return value is fully ordered
printf "\tkcsan_mb();\n"
fi
while [ "$#" -gt 0 ]; do
gen_param_check "$meta" "$1"
shift;
done
}
#gen_proto_order_variant(meta, pfx, name, sfx, order, atomic, int, arg...)
gen_proto_order_variant()
{
local meta="$1"; shift
local pfx="$1"; shift
local name="$1"; shift
local sfx="$1"; shift
local order="$1"; shift
local atomic="$1"; shift
local int="$1"; shift
local atomicname="${atomic}_${pfx}${name}${sfx}${order}"
local ret="$(gen_ret_type "${meta}" "${int}")"
local params="$(gen_params "${int}" "${atomic}" "$@")"
local checks="$(gen_params_checks "${meta}" "${order}" "$@")"
local args="$(gen_args "$@")"
local retstmt="$(gen_ret_stmt "${meta}")"
cat <<EOF
static __always_inline ${ret}
${atomicname}(${params})
{
${checks}
${retstmt}arch_${atomicname}(${args});
}
EOF
printf "\n"
}
gen_xchg()
{
local xchg="$1"; shift
local order="$1"; shift
local mult="$1"; shift
kcsan_barrier=""
if [ "${xchg%_local}" = "${xchg}" ]; then
case "$order" in
_release) kcsan_barrier="kcsan_release()" ;;
"") kcsan_barrier="kcsan_mb()" ;;
esac
fi
if [ "${xchg%${xchg#try_cmpxchg}}" = "try_cmpxchg" ] ; then
cat <<EOF
#define ${xchg}${order}(ptr, oldp, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
typeof(oldp) __ai_oldp = (oldp); \\
EOF
[ -n "$kcsan_barrier" ] && printf "\t${kcsan_barrier}; \\\\\n"
cat <<EOF
instrument_atomic_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
instrument_atomic_write(__ai_oldp, ${mult}sizeof(*__ai_oldp)); \\
arch_${xchg}${order}(__ai_ptr, __ai_oldp, __VA_ARGS__); \\
})
EOF
else
cat <<EOF
#define ${xchg}${order}(ptr, ...) \\
({ \\
typeof(ptr) __ai_ptr = (ptr); \\
EOF
[ -n "$kcsan_barrier" ] && printf "\t${kcsan_barrier}; \\\\\n"
cat <<EOF
instrument_atomic_write(__ai_ptr, ${mult}sizeof(*__ai_ptr)); \\
arch_${xchg}${order}(__ai_ptr, __VA_ARGS__); \\
})
EOF
fi
}
cat << EOF
// SPDX-License-Identifier: GPL-2.0
// Generated by $0
// DO NOT MODIFY THIS FILE DIRECTLY
/*
* This file provides wrappers with KASAN instrumentation for atomic operations.
* To use this functionality an arch's atomic.h file needs to define all
* atomic operations with arch_ prefix (e.g. arch_atomic_read()) and include
* this file at the end. This file provides atomic_read() that forwards to
* arch_atomic_read() for actual atomic operation.
* Note: if an arch atomic operation is implemented by means of other atomic
* operations (e.g. atomic_read()/atomic_cmpxchg() loop), then it needs to use
* arch_ variants (i.e. arch_atomic_read()/arch_atomic_cmpxchg()) to avoid
* double instrumentation.
*/
#ifndef _LINUX_ATOMIC_INSTRUMENTED_H
#define _LINUX_ATOMIC_INSTRUMENTED_H
#include <linux/build_bug.h>
#include <linux/compiler.h>
#include <linux/instrumented.h>
EOF
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic" "int" ${args}
done
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic64" "s64" ${args}
done
grep '^[a-z]' "$1" | while read name meta args; do
gen_proto "${meta}" "${name}" "atomic_long" "long" ${args}
done
for xchg in "xchg" "cmpxchg" "cmpxchg64" "try_cmpxchg" "try_cmpxchg64"; do
for order in "" "_acquire" "_release" "_relaxed"; do
gen_xchg "${xchg}" "${order}" ""
printf "\n"
done
done
for xchg in "cmpxchg_local" "cmpxchg64_local" "sync_cmpxchg"; do
gen_xchg "${xchg}" "" ""
printf "\n"
done
gen_xchg "cmpxchg_double" "" "2 * "
printf "\n\n"
gen_xchg "cmpxchg_double_local" "" "2 * "
cat <<EOF
#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */
EOF