linux/tools
Arnaldo Carvalho de Melo 6276594115 perf llvm: Fix script used to obtain kernel make directives to work with new kbuild
Before this patch:

  # ./perf test 39 41
  39: LLVM search and compile                               :
  39.1: Basic BPF llvm compile                              : Ok
  39.2: kbuild searching                                    : FAILED!
  39.3: Compile source for BPF prologue generation          : Skip
  39.4: Compile source for BPF relocation                   : Skip
  41: BPF filter                                            :
  41.1: Basic BPF filtering                                 : Ok
  41.2: BPF pinning                                         : Ok
  41.3: BPF prologue generation                             : FAILED!
  41.4: BPF relocation checker                              : Skip
  #

Using 'perf test -v' for these tests shows that it is not finding
uapi/linux/fs.h, which ends up being because we don't setup the right header
path. Fix it.

After this patch:

  # perf test 39 41
  39: LLVM search and compile                               :
  39.1: Basic BPF llvm compile                              : Ok
  39.2: kbuild searching                                    : Ok
  39.3: Compile source for BPF prologue generation          : Ok
  39.4: Compile source for BPF relocation                   : Ok
  41: BPF filter                                            :
  41.1: Basic BPF filtering                                 : Ok
  41.2: BPF pinning                                         : Ok
  41.3: BPF prologue generation                             : Ok
  41.4: BPF relocation checker                              : Ok
  #

Longer description:

In llvm-utils.c we use some techniques to obtain the kbuild make
directives and that recently stopped working as now 'ar' gets called and
expects to find the dummy.o used to echo these variables:

  $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS)

Add the $(CC) line to satisfy that, making sure this works with all
kernels, i.e. preserving the temp directory and files in it used for
this technique we can see that it works everywhere:

  # make -s -C /lib/modules/5.4.18-100.fc30.x86_64/build M=/tmp/tmp.qgaFHgxjZ4/ clean
  # ls -la /tmp/tmp.qgaFHgxjZ4/
  total 4
  drwx------.  2 root root   80 Feb 14 09:42 .
  drwxrwxrwt. 47 root root 1200 Feb 14 09:42 ..
  -rw-r--r--.  1 root root    0 Feb 13 17:14 dummy.c
  -rw-r--r--.  1 root root  121 Feb 13 17:14 Makefile
  #
  # cat /tmp/tmp.qgaFHgxjZ4/Makefile
  obj-y := dummy.o
  $(obj)/%.o: $(src)/%.c
          @echo -n "$(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS)"
          $(CC) -c -o $@ $<
  #

Then build with an old kernel Makefile:

  # make -s -C /lib/modules/5.4.18-100.fc30.x86_64/build M=/tmp/tmp.qgaFHgxjZ4/ dummy.o
  -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/9/include -I./arch/x86/include -I./arch/x86/include/generated  -I./include -I./arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/kconfig.h
  #
  # ls -la /tmp/tmp.qgaFHgxjZ4/
  total 8
  drwx------.  2 root root  100 Feb 14 09:43 .
  drwxrwxrwt. 47 root root 1200 Feb 14 09:43 ..
  -rw-r--r--.  1 root root    0 Feb 13 17:14 dummy.c
  -rw-r--r--.  1 root root  936 Feb 14 09:43 dummy.o
  -rw-r--r--.  1 root root  121 Feb 13 17:14 Makefile
  #

And a new one:

  # make -s -C /lib/modules/5.4.18-100.fc30.x86_64/build M=/tmp/tmp.qgaFHgxjZ4/ clean
  # ls -la /tmp/tmp.qgaFHgxjZ4/
  total 4
  drwx------.  2 root root   80 Feb 14 09:43 .
  drwxrwxrwt. 47 root root 1200 Feb 14 09:43 ..
  -rw-r--r--.  1 root root    0 Feb 13 17:14 dummy.c
  -rw-r--r--.  1 root root  121 Feb 13 17:14 Makefile
  # make -s -C /lib/modules/5.6.0-rc1+/build M=/tmp/tmp.qgaFHgxjZ4/ dummy.o
   -nostdinc -isystem /usr/lib/gcc/x86_64-redhat-linux/9/include -I/home/acme/git/linux/arch/x86/include -I./arch/x86/include/generated -I/home/acme/git/linux/include -I./include -I/home/acme/git/linux/arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I/home/acme/git/linux/include/uapi -I./include/generated/uapi -include /home/acme/git/linux/include/linux/kconfig.h
  #
  # ls -la /tmp/tmp.qgaFHgxjZ4/
  total 16
  drwx------.  2 root root  160 Feb 14 09:44 .
  drwxrwxrwt. 47 root root 1200 Feb 14 09:44 ..
  -rw-r--r--.  1 root root  158 Feb 14 09:44 built-in.a
  -rw-r--r--.  1 root root  149 Feb 14 09:44 .built-in.a.cmd
  -rw-r--r--.  1 root root    0 Feb 13 17:14 dummy.c
  -rw-r--r--.  1 root root  936 Feb 14 09:44 dummy.o
  -rw-r--r--.  1 root root  121 Feb 13 17:14 Makefile
  -rw-r--r--.  1 root root    0 Feb 14 09:44 modules.order
  #

Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: https://www.spinics.net/lists/linux-perf-users/msg10600.html
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-02-14 10:06:00 -03:00
..
accounting
arch tools headers kvm: Sync kvm headers with the kernel sources 2020-02-12 12:41:20 -03:00
bootconfig tools/bootconfig: Show the number of bootconfig nodes 2020-02-05 17:17:05 -05:00
bpf bpftool: Don't crash on missing xlated program instructions 2020-02-07 22:29:45 +01:00
build perf/ui/gtk: Fix gtk2 build 2020-01-14 12:40:33 -03:00
cgroup iocost: Fix iocost_monitor.py due to helper type mismatch 2020-01-17 11:54:35 -08:00
debugging
firewire
firmware
gpio tools: gpio: Correctly add make dependencies for gpio_utils 2019-11-13 13:46:04 +01:00
hv Tools: hv: Reopen the devices if read() or write() returns errors 2020-01-26 22:10:10 -05:00
iio tools: iio: Correctly add make dependency for iio_utils 2019-11-10 17:11:06 +00:00
include tools headers kvm: Sync linux/kvm.h with the kernel sources 2020-02-12 12:45:24 -03:00
io_uring
kvm/kvm_stat tools/kvm_stat: Fix kvm_exit filter name 2020-01-23 09:51:06 +01:00
laptop
leds
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-01-28 16:02:33 -08:00
memory-model tools/memory-model/Documentation: Add plain accesses and data races to explanation.txt 2019-10-05 11:59:44 -07:00
nfsd
objtool objtool: Fix ARCH=x86_64 build error 2020-01-22 07:54:57 +01:00
pci tools: PCI: Fix fd leakage 2019-10-29 12:04:18 +00:00
pcmcia
perf perf llvm: Fix script used to obtain kernel make directives to work with new kbuild 2020-02-14 10:06:00 -03:00
power More power manadement updates for 5.6-rc1 2020-01-31 14:36:35 -08:00
scripts
spi
testing Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-02-08 17:15:08 -08:00
thermal/tmon
time
usb usbip: Fix unsafe unaligned pointer usage 2020-01-09 16:44:26 +01:00
virtio tools/virtio: xen stub 2019-10-13 09:38:27 -04:00
vm tools/vm/slabinfo: fix sanity checks enabling 2020-01-31 10:30:38 -08:00
wmi
Makefile tools: bootconfig: Add bootconfig command 2020-01-13 13:19:39 -05:00