From patchwork Mon Sep 14 18:19:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [meta-arm] arm/scp-firmware: fix build race From: Ross Burton X-Patchwork-Id: 176504 Message-Id: <20200914181903.499094-1-ross.burton@arm.com> To: meta-arm@lists.yoctoproject.org Date: Mon, 14 Sep 2020 19:19:03 +0100 Backport a patch to fix a race in parallel builds. Change-Id: I4b33b819f2da302369ca77429f25d5c15672c5f3 Signed-off-by: Ross Burton --- ..._code-atomically-rewrite-the-generat.patch | 69 +++++++++++++++++++ .../scp-firmware/scp-firmware_2.6.0.bb | 3 +- 2 files changed, 71 insertions(+), 1 deletion(-) create mode 100644 meta-arm/recipes-bsp/scp-firmware/files/0001-tools-gen_module_code-atomically-rewrite-the-generat.patch diff --git a/meta-arm/recipes-bsp/scp-firmware/files/0001-tools-gen_module_code-atomically-rewrite-the-generat.patch b/meta-arm/recipes-bsp/scp-firmware/files/0001-tools-gen_module_code-atomically-rewrite-the-generat.patch new file mode 100644 index 0000000..05bb025 --- /dev/null +++ b/meta-arm/recipes-bsp/scp-firmware/files/0001-tools-gen_module_code-atomically-rewrite-the-generat.patch @@ -0,0 +1,69 @@ +Upstream-Status: Backport +Signed-off-by: Ross Burton + +From 34e1c04534607f5605255f39fb46e26261fc9c4e Mon Sep 17 00:00:00 2001 +From: Ross Burton +Date: Tue, 8 Sep 2020 11:49:08 +0100 +Subject: [PATCH] tools/gen_module_code: atomically rewrite the generated files + +The gen_module rule in rules.mk is marked as .PHONY, so make will +execute it whenever it is mentioned. This results in gen_module_code +being executed 64 times for a Juno build. + +However in heavily parallel builds there's a good chance that +gen_module_code is writing a file whilst the compiler is reading it +because make also doesn't know what files are generated by +gen_module_code. + +The correct fix is to adjust the Makefiles so that the dependencies are +correct but this isn't trivial, so band-aid the problem by atomically +writing the generated files. + +Change-Id: I82d44f9ea6537a91002e1f80de8861d208571630 +Signed-off-by: Ross Burton +--- + tools/gen_module_code.py | 19 ++++++++++++++----- + 1 file changed, 14 insertions(+), 5 deletions(-) + +diff --git a/tools/gen_module_code.py b/tools/gen_module_code.py +index 7b395384..ee099b71 100755 +--- a/tools/gen_module_code.py ++++ b/tools/gen_module_code.py +@@ -17,6 +17,7 @@ + import argparse + import os + import sys ++import tempfile + + DEFAULT_PATH = 'build/' + +@@ -53,13 +54,21 @@ TEMPLATE_C = "/* This file was auto generated using {} */\n" \ + + def generate_file(path, filename, content): + full_filename = os.path.join(path, filename) +- with open(full_filename, 'a+') as f: +- f.seek(0) +- if f.read() != content: ++ ++ try: ++ with open(full_filename) as f: ++ rewrite = f.read() != content ++ except FileNotFoundError: ++ rewrite = True ++ ++ if rewrite: ++ with tempfile.NamedTemporaryFile(prefix="gen-module-code", ++ dir=path, ++ delete=False, ++ mode="wt") as f: + print("[GEN] {}...".format(full_filename)) +- f.seek(0) +- f.truncate() + f.write(content) ++ os.replace(f.name, full_filename) + + + def generate_header(path, modules): +-- +2.28.0 + diff --git a/meta-arm/recipes-bsp/scp-firmware/scp-firmware_2.6.0.bb b/meta-arm/recipes-bsp/scp-firmware/scp-firmware_2.6.0.bb index 4de0912..f9510e4 100644 --- a/meta-arm/recipes-bsp/scp-firmware/scp-firmware_2.6.0.bb +++ b/meta-arm/recipes-bsp/scp-firmware/scp-firmware_2.6.0.bb @@ -6,7 +6,8 @@ LICENSE = "BSD-3-Clause & Apache-2.0" LIC_FILES_CHKSUM = "file://license.md;beginline=5;md5=9db9e3d2fb8d9300a6c3d15101b19731 \ file://cmsis/LICENSE.txt;md5=e3fc50a88d0a364313df4b21ef20c29e" -SRC_URI = "gitsm://github.com/ARM-software/SCP-firmware.git;protocol=https" +SRC_URI = "gitsm://github.com/ARM-software/SCP-firmware.git;protocol=https \ + file://0001-tools-gen_module_code-atomically-rewrite-the-generat.patch" SRCREV = "db19910aca6d1032eb0329e5fbb70a92b997f6f2" PROVIDES += "virtual/control-processor-firmware"