xref: /aosp_15_r20/external/libbpf/scripts/sync-kernel.sh (revision f7c14bbac8cf49633f2740db462ea43457973ec4)
1#!/bin/bash
2
3usage () {
4	echo "USAGE: ./sync-kernel.sh <libbpf-repo> <kernel-repo> <bpf-branch>"
5	echo ""
6	echo "Set BPF_NEXT_BASELINE to override bpf-next tree commit, otherwise read from <libbpf-repo>/CHECKPOINT-COMMIT."
7	echo "Set BPF_BASELINE to override bpf tree commit, otherwise read from <libbpf-repo>/BPF-CHECKPOINT-COMMIT."
8	echo "Set MANUAL_MODE to 1 to manually control every cherry-picked commits."
9	exit 1
10}
11
12set -eu
13
14LIBBPF_REPO=${1-""}
15LINUX_REPO=${2-""}
16BPF_BRANCH=${3-""}
17BASELINE_COMMIT=${BPF_NEXT_BASELINE:-$(cat ${LIBBPF_REPO}/CHECKPOINT-COMMIT)}
18BPF_BASELINE_COMMIT=${BPF_BASELINE:-$(cat ${LIBBPF_REPO}/BPF-CHECKPOINT-COMMIT)}
19
20if [ -z "${LIBBPF_REPO}" ] || [ -z "${LINUX_REPO}" ]; then
21	echo "Error: libbpf or linux repos are not specified"
22	usage
23fi
24if [ -z "${BPF_BRANCH}" ]; then
25	echo "Error: linux's bpf tree branch is not specified"
26	usage
27fi
28if [ -z "${BASELINE_COMMIT}" ] || [ -z "${BPF_BASELINE_COMMIT}" ]; then
29	echo "Error: bpf or bpf-next baseline commits are not provided"
30	usage
31fi
32
33SUFFIX=$(date --utc +%Y-%m-%dT%H-%M-%S.%3NZ)
34WORKDIR=$(pwd)
35TMP_DIR=$(mktemp -d)
36
37trap "cd ${WORKDIR}; exit" INT TERM EXIT
38
39declare -A PATH_MAP
40PATH_MAP=(									\
41	[tools/lib/bpf]=src							\
42	[tools/include/uapi/linux/bpf_common.h]=include/uapi/linux/bpf_common.h	\
43	[tools/include/uapi/linux/bpf.h]=include/uapi/linux/bpf.h		\
44	[tools/include/uapi/linux/btf.h]=include/uapi/linux/btf.h		\
45	[tools/include/uapi/linux/fcntl.h]=include/uapi/linux/fcntl.h		\
46	[tools/include/uapi/linux/openat2.h]=include/uapi/linux/openat2.h	\
47	[tools/include/uapi/linux/if_link.h]=include/uapi/linux/if_link.h	\
48	[tools/include/uapi/linux/if_xdp.h]=include/uapi/linux/if_xdp.h		\
49	[tools/include/uapi/linux/netdev.h]=include/uapi/linux/netdev.h		\
50	[tools/include/uapi/linux/netlink.h]=include/uapi/linux/netlink.h	\
51	[tools/include/uapi/linux/pkt_cls.h]=include/uapi/linux/pkt_cls.h	\
52	[tools/include/uapi/linux/pkt_sched.h]=include/uapi/linux/pkt_sched.h	\
53	[include/uapi/linux/perf_event.h]=include/uapi/linux/perf_event.h	\
54	[Documentation/bpf/libbpf]=docs						\
55)
56
57LIBBPF_PATHS=("${!PATH_MAP[@]}" ":^tools/lib/bpf/Makefile" ":^tools/lib/bpf/Build" ":^tools/lib/bpf/.gitignore" ":^tools/include/tools/libc_compat.h")
58LIBBPF_VIEW_PATHS=("${PATH_MAP[@]}")
59LIBBPF_VIEW_EXCLUDE_REGEX='^src/(Makefile|Build|test_libbpf\.c|bpf_helper_defs\.h|\.gitignore)$|^docs/(\.gitignore|api\.rst|conf\.py)$|^docs/sphinx/.*'
60LINUX_VIEW_EXCLUDE_REGEX='^include/tools/libc_compat.h$'
61
62LIBBPF_TREE_FILTER="mkdir -p __libbpf/include/uapi/linux __libbpf/include/tools && "$'\\\n'
63for p in "${!PATH_MAP[@]}"; do
64	LIBBPF_TREE_FILTER+="git mv -kf ${p} __libbpf/${PATH_MAP[${p}]} && "$'\\\n'
65done
66LIBBPF_TREE_FILTER+="git rm --ignore-unmatch -f __libbpf/src/{Makefile,Build,test_libbpf.c,.gitignore} >/dev/null"
67
68cd_to()
69{
70	cd ${WORKDIR} && cd "$1"
71}
72
73# Output brief single-line commit description
74# $1 - commit ref
75commit_desc()
76{
77	git log -n1 --pretty='%h ("%s")' $1
78}
79
80# Create commit single-line signature, which consists of:
81# - full commit subject
82# - author date in ISO8601 format
83# - full commit body with newlines replaced with vertical bars (|)
84# - shortstat appended at the end
85# The idea is that this single-line signature is good enough to make final
86# decision about whether two commits are the same, across different repos.
87# $1 - commit ref
88# $2 - paths filter
89commit_signature()
90{
91	local ref=$1
92	shift
93	git show --pretty='("%s")|%aI|%b' --shortstat $ref -- "${@-.}" | tr '\n' '|'
94}
95
96# Cherry-pick commits touching libbpf-related files
97# $1 - baseline_tag
98# $2 - tip_tag
99cherry_pick_commits()
100{
101	local manual_mode=${MANUAL_MODE:-0}
102	local baseline_tag=$1
103	local tip_tag=$2
104	local new_commits
105	local signature
106	local should_skip
107	local synced_cnt
108	local manual_check
109	local libbpf_conflict_cnt
110	local desc
111
112	new_commits=$(git rev-list --no-merges --topo-order --reverse ${baseline_tag}..${tip_tag} -- "${LIBBPF_PATHS[@]}")
113	for new_commit in ${new_commits}; do
114		desc="$(commit_desc ${new_commit})"
115		signature="$(commit_signature ${new_commit} "${LIBBPF_PATHS[@]}")"
116		synced_cnt=$(grep -F "${signature}" ${TMP_DIR}/libbpf_commits.txt | wc -l)
117		manual_check=0
118		if ((${synced_cnt} > 0)); then
119			# commit with the same subject is already in libbpf, but it's
120			# not 100% the same commit, so check with user
121			echo "Commit '${desc}' is synced into libbpf as:"
122			grep -F "${signature}" ${TMP_DIR}/libbpf_commits.txt | \
123				cut -d'|' -f1 | sed -e 's/^/- /'
124			if ((${manual_mode} != 1 && ${synced_cnt} == 1)); then
125				echo "Skipping '${desc}' due to unique match..."
126				continue
127			fi
128			if ((${synced_cnt} > 1)); then
129				echo "'${desc} matches multiple commits, please, double-check!"
130				manual_check=1
131			fi
132		fi
133		if ((${manual_mode} == 1 || ${manual_check} == 1)); then
134			read -p "Do you want to skip '${desc}'? [y/N]: " should_skip
135			case "${should_skip}" in
136				"y" | "Y")
137					echo "Skipping '${desc}'..."
138					continue
139					;;
140			esac
141		fi
142		# commit hasn't been synced into libbpf yet
143		echo "Picking '${desc}'..."
144		if ! git cherry-pick ${new_commit} &>/dev/null; then
145			echo "Warning! Cherry-picking '${desc} failed, checking if it's non-libbpf files causing problems..."
146			libbpf_conflict_cnt=$(git diff --name-only --diff-filter=U -- "${LIBBPF_PATHS[@]}" | wc -l)
147			conflict_cnt=$(git diff --name-only | wc -l)
148			prompt_resolution=1
149
150			if ((${libbpf_conflict_cnt} == 0)); then
151				echo "Looks like only non-libbpf files have conflicts, ignoring..."
152				if ((${conflict_cnt} == 0)); then
153					echo "Empty cherry-pick, skipping it..."
154					git cherry-pick --abort
155					continue
156				fi
157
158				git add .
159				# GIT_EDITOR=true to avoid editor popping up to edit commit message
160				if ! GIT_EDITOR=true git cherry-pick --continue &>/dev/null; then
161					echo "Error! That still failed! Please resolve manually."
162				else
163					echo "Success! All cherry-pick conflicts were resolved for '${desc}'!"
164					prompt_resolution=0
165				fi
166			fi
167
168			if ((${prompt_resolution} == 1)); then
169				read -p "Error! Cherry-picking '${desc}' failed, please fix manually and press <return> to proceed..."
170			fi
171		fi
172		# Append signature of just cherry-picked commit to avoid
173		# potentially cherry-picking the same commit twice later when
174		# processing bpf tree commits. At this point we don't know yet
175		# the final commit sha in libbpf repo, so we record Linux SHA
176		# instead as LINUX_<sha>.
177		echo LINUX_$(git log --pretty='%h' -n1) "${signature}" >> ${TMP_DIR}/libbpf_commits.txt
178	done
179}
180
181cleanup()
182{
183	echo "Cleaning up..."
184	rm -r ${TMP_DIR}
185	cd_to ${LINUX_REPO}
186	git checkout ${TIP_SYM_REF}
187	git branch -D ${BASELINE_TAG} ${TIP_TAG} ${BPF_BASELINE_TAG} ${BPF_TIP_TAG} \
188		      ${SQUASH_BASE_TAG} ${SQUASH_TIP_TAG} ${VIEW_TAG} || true
189
190	cd_to .
191	echo "DONE."
192}
193
194
195cd_to ${LIBBPF_REPO}
196GITHUB_ABS_DIR=$(pwd)
197echo "Dumping existing libbpf commit signatures..."
198for h in $(git log --pretty='%h' -n500); do
199	echo $h "$(commit_signature $h)" >> ${TMP_DIR}/libbpf_commits.txt
200done
201
202# Use current kernel repo HEAD as a source of patches
203cd_to ${LINUX_REPO}
204LINUX_ABS_DIR=$(pwd)
205TIP_SYM_REF=$(git symbolic-ref -q --short HEAD || git rev-parse HEAD)
206TIP_COMMIT=$(git rev-parse HEAD)
207BPF_TIP_COMMIT=$(git rev-parse ${BPF_BRANCH})
208BASELINE_TAG=libbpf-baseline-${SUFFIX}
209TIP_TAG=libbpf-tip-${SUFFIX}
210BPF_BASELINE_TAG=libbpf-bpf-baseline-${SUFFIX}
211BPF_TIP_TAG=libbpf-bpf-tip-${SUFFIX}
212VIEW_TAG=libbpf-view-${SUFFIX}
213LIBBPF_SYNC_TAG=libbpf-sync-${SUFFIX}
214
215# Squash state of kernel repo at baseline into single commit
216SQUASH_BASE_TAG=libbpf-squash-base-${SUFFIX}
217SQUASH_TIP_TAG=libbpf-squash-tip-${SUFFIX}
218SQUASH_COMMIT=$(git commit-tree ${BASELINE_COMMIT}^{tree} -m "BASELINE SQUASH ${BASELINE_COMMIT}")
219
220echo "WORKDIR:          ${WORKDIR}"
221echo "LINUX REPO:       ${LINUX_REPO}"
222echo "LIBBPF REPO:      ${LIBBPF_REPO}"
223echo "TEMP DIR:         ${TMP_DIR}"
224echo "SUFFIX:           ${SUFFIX}"
225echo "BASE COMMIT:      '$(commit_desc ${BASELINE_COMMIT})'"
226echo "TIP COMMIT:       '$(commit_desc ${TIP_COMMIT})'"
227echo "BPF BASE COMMIT:  '$(commit_desc ${BPF_BASELINE_COMMIT})'"
228echo "BPF TIP COMMIT:   '$(commit_desc ${BPF_TIP_COMMIT})'"
229echo "SQUASH COMMIT:    ${SQUASH_COMMIT}"
230echo "BASELINE TAG:     ${BASELINE_TAG}"
231echo "TIP TAG:          ${TIP_TAG}"
232echo "BPF BASELINE TAG: ${BPF_BASELINE_TAG}"
233echo "BPF TIP TAG:      ${BPF_TIP_TAG}"
234echo "SQUASH BASE TAG:  ${SQUASH_BASE_TAG}"
235echo "SQUASH TIP TAG:   ${SQUASH_TIP_TAG}"
236echo "VIEW TAG:         ${VIEW_TAG}"
237echo "LIBBPF SYNC TAG:  ${LIBBPF_SYNC_TAG}"
238echo "PATCHES:          ${TMP_DIR}/patches"
239
240git branch ${BASELINE_TAG} ${BASELINE_COMMIT}
241git branch ${TIP_TAG} ${TIP_COMMIT}
242git branch ${BPF_BASELINE_TAG} ${BPF_BASELINE_COMMIT}
243git branch ${BPF_TIP_TAG} ${BPF_TIP_COMMIT}
244git branch ${SQUASH_BASE_TAG} ${SQUASH_COMMIT}
245git checkout -b ${SQUASH_TIP_TAG} ${SQUASH_COMMIT}
246
247# Cherry-pick new commits onto squashed baseline commit
248cherry_pick_commits ${BASELINE_TAG} ${TIP_TAG}
249cherry_pick_commits ${BPF_BASELINE_TAG} ${BPF_TIP_TAG}
250
251# Move all libbpf files into __libbpf directory.
252FILTER_BRANCH_SQUELCH_WARNING=1 git filter-branch --prune-empty -f --tree-filter "${LIBBPF_TREE_FILTER}" ${SQUASH_TIP_TAG} ${SQUASH_BASE_TAG}
253# Make __libbpf a new root directory
254FILTER_BRANCH_SQUELCH_WARNING=1 git filter-branch --prune-empty -f --subdirectory-filter __libbpf ${SQUASH_TIP_TAG} ${SQUASH_BASE_TAG}
255
256# If there are no new commits with  libbpf-related changes, bail out
257COMMIT_CNT=$(git rev-list --count ${SQUASH_BASE_TAG}..${SQUASH_TIP_TAG})
258if ((${COMMIT_CNT} <= 0)); then
259    echo "No new changes to apply, we are done!"
260    cleanup
261    exit 2
262fi
263
264# Exclude baseline commit and generate nice cover letter with summary
265git format-patch --no-signature ${SQUASH_BASE_TAG}..${SQUASH_TIP_TAG} --cover-letter -o ${TMP_DIR}/patches
266
267# Now is time to re-apply libbpf-related linux patches to libbpf repo
268cd_to ${LIBBPF_REPO}
269git checkout -b ${LIBBPF_SYNC_TAG}
270
271for patch in $(ls -1 ${TMP_DIR}/patches | tail -n +2); do
272	if ! git am -3 --committer-date-is-author-date "${TMP_DIR}/patches/${patch}"; then
273		if ! patch -p1 --merge < "${TMP_DIR}/patches/${patch}"; then
274			read -p "Applying ${TMP_DIR}/patches/${patch} failed, please resolve manually and press <return> to proceed..."
275		fi
276		git am --continue
277	fi
278done
279
280# Generate bpf_helper_defs.h and commit, if anything changed
281# restore Linux tip to use bpf_doc.py
282cd_to ${LINUX_REPO}
283git checkout ${TIP_TAG}
284# re-generate bpf_helper_defs.h
285cd_to ${LIBBPF_REPO}
286"${LINUX_ABS_DIR}/scripts/bpf_doc.py" --header					      \
287	--file include/uapi/linux/bpf.h > src/bpf_helper_defs.h
288# if anything changed, commit it
289helpers_changes=$(git status --porcelain src/bpf_helper_defs.h | wc -l)
290if ((${helpers_changes} == 1)); then
291	git add src/bpf_helper_defs.h
292	git commit -s -m "sync: auto-generate latest BPF helpers
293
294Latest changes to BPF helper definitions.
295" -- src/bpf_helper_defs.h
296fi
297
298# Use generated cover-letter as a template for "sync commit" with
299# baseline and checkpoint commits from kernel repo (and leave summary
300# from cover letter intact, of course)
301echo ${TIP_COMMIT} > CHECKPOINT-COMMIT &&					      \
302echo ${BPF_TIP_COMMIT} > BPF-CHECKPOINT-COMMIT &&				      \
303git add CHECKPOINT-COMMIT &&							      \
304git add BPF-CHECKPOINT-COMMIT &&						      \
305awk '/\*\*\* BLURB HERE \*\*\*/ {p=1} p' ${TMP_DIR}/patches/0000-cover-letter.patch | \
306sed "s/\*\*\* BLURB HERE \*\*\*/\
307sync: latest libbpf changes from kernel\n\
308\n\
309Syncing latest libbpf commits from kernel repository.\n\
310Baseline bpf-next commit:   ${BASELINE_COMMIT}\n\
311Checkpoint bpf-next commit: ${TIP_COMMIT}\n\
312Baseline bpf commit:        ${BPF_BASELINE_COMMIT}\n\
313Checkpoint bpf commit:      ${BPF_TIP_COMMIT}/" |				      \
314git commit -s --file=-
315
316echo "SUCCESS! ${COMMIT_CNT} commits synced."
317
318echo "Verifying Linux's and Github's libbpf state"
319
320cd_to ${LINUX_REPO}
321git checkout -b ${VIEW_TAG} ${TIP_COMMIT}
322FILTER_BRANCH_SQUELCH_WARNING=1 git filter-branch -f --tree-filter "${LIBBPF_TREE_FILTER}" ${VIEW_TAG}^..${VIEW_TAG}
323FILTER_BRANCH_SQUELCH_WARNING=1 git filter-branch -f --subdirectory-filter __libbpf ${VIEW_TAG}^..${VIEW_TAG}
324git ls-files -- "${LIBBPF_VIEW_PATHS[@]}" | grep -v -E "${LINUX_VIEW_EXCLUDE_REGEX}" > ${TMP_DIR}/linux-view.ls
325
326cd_to ${LIBBPF_REPO}
327git ls-files -- "${LIBBPF_VIEW_PATHS[@]}" | grep -v -E "${LIBBPF_VIEW_EXCLUDE_REGEX}" > ${TMP_DIR}/github-view.ls
328
329echo "Comparing list of files..."
330diff -u ${TMP_DIR}/linux-view.ls ${TMP_DIR}/github-view.ls
331echo "Comparing file contents..."
332CONSISTENT=1
333for F in $(cat ${TMP_DIR}/linux-view.ls); do
334	if ! diff -u "${LINUX_ABS_DIR}/${F}" "${GITHUB_ABS_DIR}/${F}"; then
335		echo "${LINUX_ABS_DIR}/${F} and ${GITHUB_ABS_DIR}/${F} are different!"
336		CONSISTENT=0
337	fi
338done
339if ((${CONSISTENT} == 1)); then
340	echo "Great! Content is identical!"
341else
342	ignore_inconsistency=n
343	echo "Unfortunately, there are some inconsistencies, please double check."
344	read -p "Does everything look good? [y/N]: " ignore_inconsistency
345	case "${ignore_inconsistency}" in
346		"y" | "Y")
347			echo "Ok, proceeding..."
348			;;
349		*)
350			echo "Oops, exiting with error..."
351			exit 4
352	esac
353fi
354
355cleanup
356