sync-to-kernel.sh: Updated to sync to kernel and renamed accordingly

The scx repo is going to serve as the source of truth for sched_ext
schedulers. Reverse the sync direction and include syncing rust-user
schedulers too.

scheds/sync-to-kernel.sh

@@ -1,26 +1,47 @@
 #!/bin/bash
 
 set -e
+shopt -s globstar
 
 if [ $# -ne 1 ]; then
     echo "Usage: sync-to-kernel.sh KERNEL_TREE_TO_SYNC_TO" 1>&2
     exit 1
 fi
 
-headers="
+# We sync all schedulers under kernel-examples but only the following ones
+# under rust-user.
+rust_scheds=(scx_rusty scx_layered)
 
+headers=($(git ls-files include | grep -v include/vmlinux))
+scheds=($(git ls-files kernel-examples ${rust_scheds[@]/#/rust-user/} | grep -v meson.build))
 kernel="$1/tools/sched_ext"
-headers="$kernel/include"
-c_scheds="$kernel/*.[hc]"
-files=(include/common/* kernel-examples/*.[hc])
 
-echo "Syncing ${#files[@]} files from \"$1\""
+echo "Syncing ${#headers[@]} headers and ${#scheds[@]} scheduler source files to $kernel"
+
+srcs=("${headers[@]}" "${scheds[@]}")
+dsts=()
+
+# Header paths are the same relative to the base directories.
+for file in ${headers[@]}; do
+    dsts+=("$kernel/${file}")
+done
+
+# Sched files should drop the first directory component. ie.
+# kernel-examples/scx_simple.bpf.c should be synced to
+# $kernel/scx_simple.bpf.c.
+for file in ${scheds[@]}; do
+    dsts+=("$kernel/${file#*/}")
+done
+	    
+## debug
+#for ((i=0;i<${#srcs[@]};i++)); do
+#    echo "${srcs[i]} -> ${dsts[i]}"
+#done
 
 nr_missing=0
-for i in "${files[@]}"; do
-    base=$(basename "$i")
-    if [ ! -f "$kernel/$base" ]; then
-	echo "ERROR: $base does not exist in $kernel" 1>&2
+for dst in "${dsts[@]}"; do
+    if [ ! -f "$dst" ]; then
+	echo "ERROR: $dst does not exist" 1>&2
 	nr_missing=$((nr_missing+1))
     fi
 done
@@ -30,14 +51,32 @@ if [ $nr_missing -gt 0 ]; then
 fi
 
 nr_skipped=0
-for i in "${files[@]}"; do
-    base=$(basename "$i")
-    if cmp -s "$kernel/$base" $i; then
+for ((i=0;i<${#srcs[@]};i++)); do
+    src="${srcs[i]}"
+    dst="${dsts[i]}"
+    orig="$src"
+
+    #
+    # As scx_utils is in this repo, rust-user schedulers point directly to
+    # the source in the tree. As they break outside this tree, drop them
+    # before syncing Cargo.toml files.
+    #
+    if [[ "$src" == */Cargo.toml ]]; then
+	tmp=$(mktemp)
+	sed -r 's/^scx_utils =.*version\s*=\s*"([^"]*)".*$/scx_utils = \"\1"/' < "$src" > "$tmp"
+	src="$tmp"
+    fi
+
+    if cmp -s "$src" "$dst"; then
 	nr_skipped=$((nr_skipped+1))
 	continue
     fi
-    echo "Syncing $base"
-    cp -f "$kernel/$base" $i
+    if [[ "$orig" == */Cargo.toml ]]; then
+	echo "Syncing $orig (dropped path from scx_utils dependency)"
+    else
+	echo "Syncing $orig"
+    fi
+    cp -f "$src" "$dst"
 done
 
-echo "Skipped $nr_skipped files as they are unchanged"
+echo "Skipped $nr_skipped unchanged files"