From f4cdf7ca9a1fdcca413157df19753f388a5a224e Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 19 Aug 2026 10:09:22 -0700 Subject: Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ... --- tools/perf/Documentation/Build.txt | 116 +++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 tools/perf/Documentation/Build.txt (limited to 'tools/perf/Documentation/Build.txt') diff --git a/tools/perf/Documentation/Build.txt b/tools/perf/Documentation/Build.txt new file mode 100644 index 000000000..57b226e7f --- /dev/null +++ b/tools/perf/Documentation/Build.txt @@ -0,0 +1,116 @@ + +1) perf build +============= +The perf build process consists of several separated building blocks, +which are linked together to form the perf binary: + - libperf library (static) + - perf builtin commands + - traceevent library (static) + - GTK ui library + +Several makefiles govern the perf build: + + - Makefile + top level Makefile working as a wrapper that calls the main + Makefile.perf with a -j option to do parallel builds. + + - Makefile.perf + main makefile that triggers build of all perf objects including + installation and documentation processing. + + - tools/build/Makefile.build + main makefile of the build framework + + - tools/build/Build.include + build framework generic definitions + + - Build makefiles + makefiles that defines build objects + +Please refer to tools/build/Documentation/Build.txt for more +information about build framework. + + +2) perf build +============= +The Makefile.perf triggers the build framework for build objects: + perf, libperf, gtk + +resulting in following objects: + $ ls *-in.o + gtk-in.o libperf-in.o perf-in.o + +Those objects are then used in final linking: + libperf-gtk.so <- gtk-in.o libperf-in.o + perf <- perf-in.o libperf-in.o + + +NOTE this description is omitting other libraries involved, only + focusing on build framework outcomes + +3) Build with ASan or UBSan +========================== + $ cd tools/perf + $ make DESTDIR=/usr + $ make DESTDIR=/usr install + +AddressSanitizer (or ASan) is a GCC feature that detects memory corruption bugs +such as buffer overflows and memory leaks. + + $ cd tools/perf + $ make DEBUG=1 EXTRA_CFLAGS='-fno-omit-frame-pointer -fsanitize=address' + $ ASAN_OPTIONS=log_path=asan.log ./perf record -a + +ASan outputs all detected issues into a log file named 'asan.log.'. + +UndefinedBehaviorSanitizer (or UBSan) is a fast undefined behavior detector +supported by GCC. UBSan detects undefined behaviors of programs at runtime. + + $ cd tools/perf + $ make DEBUG=1 EXTRA_CFLAGS='-fno-omit-frame-pointer -fsanitize=undefined' + $ UBSAN_OPTIONS=print_stacktrace=1 ./perf record -a + +If UBSan detects any problem at runtime, it outputs a “runtime error:” message. + +4) Cross compilation +==================== +As Multiarch is commonly supported in Linux distributions, we can install +libraries for multiple architectures on the same system and then cross-compile +Linux perf. For example, Aarch64 libraries and toolchains can be installed on +an x86_64 machine, allowing us to compile perf for an Aarch64 target. + +Below is the command for building the perf with dynamic linking. + + $ cd /path/to/Linux + $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -C tools/perf + +For static linking, the option `LDFLAGS="-static"` is required. + + $ make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \ + LDFLAGS="-static" -C tools/perf + +In the embedded system world, a use case is to explicitly specify the package +configuration paths for cross building: + + $ PKG_CONFIG_SYSROOT_DIR="/path/to/cross/build/sysroot" \ + PKG_CONFIG_LIBDIR="/usr/lib/:/usr/local/lib" \ + make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -C tools/perf + +In this case, the variable PKG_CONFIG_SYSROOT_DIR can be used alongside the +variable PKG_CONFIG_LIBDIR or PKG_CONFIG_PATH to prepend the sysroot path to +the library paths for cross compilation. + +5) Build with Clang +=================== +By default, the makefile uses GCC as compiler. With specifying environment +variables HOSTCC, CC and CXX, it allows to build perf with Clang. + +Using Clang for a native build: + + $ HOSTCC=clang CC=clang CXX=clang++ make -C tools/perf + +Specifying ARCH and CROSS_COMPILE for cross compilation: + + $ HOSTCC=clang CC=clang CXX=clang++ \ + ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- \ + make -C tools/perf -- cgit v1.3.1