kernel_headers: Fix headers not detected in incremental builds

Currently the Soong logic doesn't kick in if a change updates
headers but doesn't update gen_headers_arm*.bp files for
incremental builds. Fix the issue by making inputs to the
kernel_headers.py script as variables instead of a list.

Change-Id: I9737f6d655848458bfda70b8c6f4d9aa896a98fc
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
[bharad@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Naitik Bharadiya <bharad@codeaurora.org>
[schikk@codeaurora.org: resolve trivial merge conflicts]
Signed-off-by: Swetha Chikkaboraiah <schikk@codeaurora.org>

1 files changed, 36 insertions, 24 deletions

diff --git a/kernel_headers.py b/kernel_headers.py
index 1dacc4d974a3..d36ca87d8cb4 100644
--- a/kernel_headers.py
+++ b/kernel_headers.py
@@ -597,7 +597,7 @@ def gen_blueprints(
   arch_prefix = os.path.join('arch', header_arch, generic_prefix)
   generic_src = os.path.join(generic_prefix, rel_glob)
   arch_src = os.path.join(arch_prefix, rel_glob)
-  techpack_src = 'techpack/*'
+  techpack_src = os.path.join('techpack/*',generic_prefix, '*',rel_glob)
 
   # Excluded sources, architecture specific.
   exclude_srcs = []
@@ -645,7 +645,27 @@ def gen_blueprints(
     f.write('// ***** DO NOT EDIT *****\n')
     f.write('// This file is generated by %s\n' % kernel_headers_py)
     f.write('\n')
-    f.write('gen_headers_%s = [\n' % header_arch)
+    f.write('gen_headers_srcs_%s = [\n' % header_arch)
+    f.write('    "%s",\n' % rel_arch_asm_kbuild)
+    f.write('    "%s",\n' % rel_asm_generic_kbuild)
+    f.write('    "%s",\n' % makefile)
+
+    if header_arch == "arm":
+      f.write('    "%s",\n' % arm_syscall_tbl)
+
+    f.write('    "%s",\n' % generic_src)
+    f.write('    "%s",\n' % arch_src)
+    f.write(']\n')
+    f.write('\n')
+
+    if exclude_srcs:
+      f.write('gen_headers_exclude_srcs_%s = [\n' % header_arch)
+      for h in exclude_srcs:
+        f.write('    "%s",\n' % os.path.join(generic_prefix, h))
+      f.write(']\n')
+      f.write('\n')
+
+    f.write('gen_headers_out_%s = [\n' % header_arch)
 
     if generated_list:
       f.write('\n')
@@ -700,7 +720,10 @@ def gen_blueprints(
     f.write('    // checked later to ensure that it matches the checked-\n')
     f.write('    // in version (this file).\n')
     f.write('    name: "%s",\n' % gen_blueprints_module_name)
-    f.write('    srcs: ["%s", "%s", "%s"],\n' % (rel_arch_asm_kbuild, rel_asm_generic_kbuild, arch_src))
+    f.write('    srcs: gen_headers_srcs_%s,\n' % header_arch)
+    if exclude_srcs:
+      f.write('    exclude_srcs: gen_headers_exclude_srcs_%s,\n' % header_arch)
+
     f.write('    tool_files: ["kernel_headers.py"],\n')
     f.write('    cmd: "python3 $(location kernel_headers.py) " +\n')
     f.write('        kernel_headers_verbose +\n')
@@ -709,7 +732,8 @@ def gen_blueprints(
     f.write('        "--arch_asm_kbuild $(location %s) " +\n' % rel_arch_asm_kbuild)
     f.write('        "--arch_include_uapi $(locations %s) " +\n' % arch_src)
     f.write('        "--asm_generic_kbuild $(location %s) " +\n' % rel_asm_generic_kbuild)
-    f.write('        "blueprints",\n')
+    f.write('        "blueprints " +\n')
+    f.write('        "# $(in)",\n')
     f.write('    out: ["gen_headers_%s.bp"],\n' % header_arch)
     f.write('}\n')
     f.write('\n')
@@ -724,25 +748,13 @@ def gen_blueprints(
       f.write('        "%s",\n' % arm_syscall_tool)
 
     f.write('    ],\n')
-    f.write('    srcs: [\n')
-    f.write('        "%s",\n' % rel_arch_asm_kbuild)
-    f.write('        "%s",\n' % rel_asm_generic_kbuild)
+    f.write('    srcs: gen_headers_srcs_%s +[\n' % header_arch)
     f.write('        "%s",\n' % old_gen_headers_bp)
     f.write('        ":%s",\n' % gen_blueprints_module_name)
-    f.write('        "%s",\n' % makefile)
-
-    if header_arch == "arm":
-      f.write('        "%s",\n' % arm_syscall_tbl)
-
-    f.write('        "%s",\n' % generic_src)
-    f.write('        "%s",\n' % arch_src)
     f.write('    ],\n')
 
     if exclude_srcs:
-      f.write('    exclude_srcs: [\n')
-      for h in exclude_srcs:
-        f.write('        "%s",\n' % os.path.join(generic_prefix, h))
-      f.write('    ],\n')
+      f.write('    exclude_srcs: gen_headers_exclude_srcs_%s,\n' % header_arch)
 
     f.write('    cmd: "python3 $(location %s) " +\n' % kernel_headers_py)
     f.write('        kernel_headers_verbose +\n')
@@ -762,14 +774,14 @@ def gen_blueprints(
 
     f.write('        "--headers_install $(location %s) " +\n' % headers_install_sh)
     f.write('        "--include_uapi $(locations %s)",\n' % generic_src)
-    f.write('    out: ["linux/version.h"] + gen_headers_%s,\n' % header_arch)
+    f.write('    out: ["linux/version.h"] + gen_headers_out_%s,\n' % header_arch)
     f.write('}\n')
 
     return 0
 
 def parse_bp_for_headers(file_name, headers):
   parsing_headers = False
-  pattern = re.compile("gen_headers_[a-zA-Z0-9]+\s*=\s*\[\s*")
+  pattern = re.compile("gen_headers_out_[a-zA-Z0-9]+\s*=\s*\[\s*")
   with open(file_name, 'r') as f:
     for line in f:
       line = line.strip()
@@ -1033,13 +1045,13 @@ def main():
   if args.verbose:
     print('module_dir [%s]' % module_dir)
 
-  # Get list of techpack uapi headers to be exported from techpack/* directories.
-  techpack_uapi = extract_techpack_uapi_headers(args.verbose, module_dir)
+  techpack_include_uapi = []
+
 
   if args.mode == 'blueprints':
     return gen_blueprints(
         args.verbose, args.header_arch, args.gen_dir, args.arch_asm_kbuild,
-        args.asm_generic_kbuild, module_dir, rel_arch_asm_kbuild, rel_asm_generic_kbuild, args.arch_include_uapi, techpack_uapi)
+        args.asm_generic_kbuild, module_dir, rel_arch_asm_kbuild, rel_asm_generic_kbuild, args.arch_include_uapi, techpack_include_uapi)
 
   if args.mode == 'headers':
     if args.verbose:
@@ -1054,7 +1066,7 @@ def main():
         args.verbose, args.header_arch, args.gen_dir, args.arch_asm_kbuild,
         args.asm_generic_kbuild, module_dir, args.old_gen_headers_bp, args.new_gen_headers_bp,
         args.version_makefile, args.arch_syscall_tool, args.arch_syscall_tbl,
-        args.headers_install, args.include_uapi, args.arch_include_uapi, techpack_uapi)
+        args.headers_install, args.include_uapi, args.arch_include_uapi, techpack_include_uapi)
 
   print('error: unknown mode: %s' % args.mode)
   return 1