From 42d984025be94d7fdb80f1554436df66dd2acb16 Mon Sep 17 00:00:00 2001
From: Leonard Foerster <foersleo@amazon.com>
Date: Thu, 27 Jul 2023 07:10:10 +0000
Subject: [PATCH 1/3] tools/diff-kernel-config: Fix usage text to reflect
 reality

In commit
  43234d3cc4 - tools/diff-kernel-config: Adjust script to work on variants
we switched from specifying kernel versions to specifying variants. The
kernel versions are then parsed from the variant definition which has
advantages. Properly represent that in the usage message.

Signed-off-by: Leonard Foerster <foersleo@amazon.com>
---
 tools/diff-kernel-config | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/diff-kernel-config b/tools/diff-kernel-config
index 350b978a431..06ce0de9445 100755
--- a/tools/diff-kernel-config
+++ b/tools/diff-kernel-config
@@ -31,7 +31,7 @@ bail() {
 
 usage() {
     cat <<EOF
-Usage: $0 -b GITREV_BEFORE -a GITREV_AFTER -o OUTPUT_DIR [-k KERNEL_VERSION] [-h]
+Usage: $0 -b GITREV_BEFORE -a GITREV_AFTER -o OUTPUT_DIR [-v VARIANT] [-h]
 Compare kernel configurations before and after a series of commits.
 
     -a, --after         new Git revision to compare from

From dfac598fd5be03b26b337ee5415123c61f1ca4cf Mon Sep 17 00:00:00 2001
From: Leonard Foerster <foersleo@amazon.com>
Date: Thu, 27 Jul 2023 07:17:01 +0000
Subject: [PATCH 2/3] tools/diff-kernel-config: Add release number to full
 kernel version

When saving the full kernel version for later reference in the kernel
mapping we may come across situations where we update to a newer version
of our base kernel srpm from Amazon Linux which added only added patches
from Amazon Linux but stayed at the same upstream base version. The
before and after would be indistinguishable when only comparing the
version. Add the release number to disambiguate in that situation.

Signed-off-by: Leonard Foerster <foersleo@amazon.com>
---
 tools/diff-kernel-config | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/diff-kernel-config b/tools/diff-kernel-config
index 06ce0de9445..3f5f28476f3 100755
--- a/tools/diff-kernel-config
+++ b/tools/diff-kernel-config
@@ -206,7 +206,7 @@ for state in after before; do
                     ;;
             esac
 
-            kver_full=$(rpm --query --queryformat '%{VERSION}' "${kernel_rpm}")
+            kver_full=$(rpm --query --queryformat '%{VERSION}-%{RELEASE}' "${kernel_rpm}")
 
             #
             # Extract kernel config

From d7c90b231047be2469a2164df5f663731262d4fb Mon Sep 17 00:00:00 2001
From: Leonard Foerster <foersleo@amazon.com>
Date: Tue, 20 Jun 2023 08:27:24 +0000
Subject: [PATCH 3/3] tools/diff-kernel-config: Add resume functionality

Sometimes, the script may fail for a specific variant after we already
have spent time successfully building other variants. In order to not
let that time go to waste, enable resuming of previous runs of the
script. Be aware that the invocation has to be the same as the original
invocation, plus the resume flag.

Signed-off-by: Leonard Foerster <foersleo@amazon.com>
---
 tools/diff-kernel-config | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/tools/diff-kernel-config b/tools/diff-kernel-config
index 3f5f28476f3..c433c63db74 100755
--- a/tools/diff-kernel-config
+++ b/tools/diff-kernel-config
@@ -31,7 +31,7 @@ bail() {
 
 usage() {
     cat <<EOF
-Usage: $0 -b GITREV_BEFORE -a GITREV_AFTER -o OUTPUT_DIR [-v VARIANT] [-h]
+Usage: $0 -b GITREV_BEFORE -a GITREV_AFTER -o OUTPUT_DIR [-v VARIANT] [-r] [-h]
 Compare kernel configurations before and after a series of commits.
 
     -a, --after         new Git revision to compare from
@@ -40,6 +40,8 @@ Compare kernel configurations before and after a series of commits.
                         be given multiple times (optional, defaults to this list:
                         'aws-k8s-1.23', 'metal-k8s-1.23', 'aws-dev', 'metal-dev')
     -o, --output-dir    path to the output directory; must not exist yet
+    -r, --resume        resume work on a previous invocation; check which parts
+                        already exist in OUTPUT_DIR and skip builds accordingly
     -h, --help          show this help text
 
 Example invocation:
@@ -84,6 +86,8 @@ while [[ $# -gt 0 ]]; do
             shift; variants+=( "$1" ) ;;
         -o|--output-dir)
             shift; output_dir=$1 ;;
+        -r|--resume)
+            shift; resume=1 ;;
         -h|--help)
             usage; exit 0 ;;
         *)
@@ -102,7 +106,7 @@ done
 readonly variants
 
 [[ -n ${output_dir} ]] || usage_error 'require -o|--output-dir'
-[[ -e ${output_dir} ]] && bail "Output directory '${output_dir}' exists already, not touching it"
+[[ -e ${output_dir} && ! -v resume ]] && bail "Output directory '${output_dir}' exists already, not touching it"
 readonly output_dir
 
 # Validate and resolve the given before and after Git revisions. Resolving
@@ -163,6 +167,12 @@ for state in after before; do
         kernel_versions+=( "${kver}" )
 
         for arch in "${arches[@]}"; do
+            config_path=${output_dir}/config-${arch}-${variant}-${state}
+
+            if [[ -v resume && -e ${config_path} ]]; then
+                echo "${config_path} already exists, skipping"
+                continue
+            fi
 
             debug_id="state=${state} arch=${arch} variant=${variant} kernel=${kver}"
 
@@ -212,7 +222,6 @@ for state in after before; do
             # Extract kernel config
             #
 
-            config_path=${output_dir}/config-${arch}-${variant}-${state}
             rpm2cpio "${kernel_rpm}" \
                 | cpio --quiet --extract --to-stdout ./boot/config >"${config_path}"
             [[ -s "${config_path}" ]] || bail "Failed to extract config for ${debug_id}"