Thread (165 messages) 165 messages, 13 authors, 2021-02-22

Re: [dpdk-dev] [PATCH v3 0/4] add checking of header includes

From: Bruce Richardson <hidden>
Date: 2021-01-26 14:39:36

On Tue, Jan 26, 2021 at 02:24:02PM +0000, Bruce Richardson wrote:
On Tue, Jan 26, 2021 at 03:04:25PM +0100, David Marchand wrote:
quoted
On Tue, Jan 26, 2021 at 12:15 PM Bruce Richardson
[off-list ref] wrote:
quoted
On Mon, Jan 25, 2021 at 04:51:19PM +0100, David Marchand wrote:
quoted
On Mon, Jan 25, 2021 at 3:11 PM Bruce Richardson
[off-list ref] wrote:
quoted
As a general principle, each header file should include any other
headers it needs to provide data type definitions or macros. For
example, any header using the uintX_t types in structures or function
prototypes should include "stdint.h" to provide those type definitions.

In practice, while many, but not all, headers in DPDK did include all
necessary headers, it was never actually checked that each header could
be included in a C file and compiled without having any compiler errors
about missing definitions.  The script "check-includes.sh" could be used
for this job, but it was not called out in the documentation, so many
contributors may not have been aware of it's existance. It also was
difficult to run from a source-code directory, as the script did not
automatically allow finding of headers from one DPDK library directory
to another [this was probably based on running it on a build created by
the "make" build system, where all headers were in a single directory].
To attempt to have a build-system integrated replacement, this patchset
adds a "chkincs" app in the buildtools directory to verify this on an
ongoing basis.

This chkincs app does nothing when run, and is not installed as part of
a DPDK "ninja install", it's for build-time checking only. Its source
code consists of one C file per public DPDK header, where that C file
contains nothing except an include for that header.  Therefore, if any
header is added to the lib folder which fails to compile when included
alone, the build of chkincs will fail with a suitable error message.
Since this compile checking is not needed on most builds of DPDK, the
building of chkincs is disabled by default, but can be enabled by the
"test_includes" meson option. To catch errors with patch submissions,
the final patch of this series enables it for a single build in
test-meson-builds script.

Future work could involve doing similar checks on headers for C++
compatibility, which was something done by the check-includes.sh script
but which is missing here..

V3:
* Shrunk patchset as most header fixes already applied
* Moved chkincs from "apps" to the "buildtools" directory, which is a
  better location for something not for installation for end-user use.
* Added patch to drop check-includes script.

V2:
* Add maintainers file entry for new app
* Drop patch for c11 ring header
* Use build variable "headers_no_chkincs" for tracking exceptions

Bruce Richardson (4):
  eal: add missing include to mcslock
  build: separate out headers for include checking
  buildtools/chkincs: add app to verify header includes
  devtools: remove check-includes script

 MAINTAINERS                                  |   5 +-
 buildtools/chkincs/gen_c_file_for_header.py  |  12 +
 buildtools/chkincs/main.c                    |   4 +
 buildtools/chkincs/meson.build               |  40 +++
 devtools/check-includes.sh                   | 259 -------------------
 devtools/test-meson-builds.sh                |   2 +-
 doc/guides/contributing/coding_style.rst     |  12 +
 lib/librte_eal/include/generic/rte_mcslock.h |   1 +
 lib/librte_eal/include/meson.build           |   2 +-
 lib/librte_eal/x86/include/meson.build       |  14 +-
 lib/librte_ethdev/meson.build                |   4 +-
 lib/librte_hash/meson.build                  |   4 +-
 lib/librte_ipsec/meson.build                 |   3 +-
 lib/librte_lpm/meson.build                   |   2 +-
 lib/librte_regexdev/meson.build              |   2 +-
 lib/librte_ring/meson.build                  |   4 +-
 lib/librte_stack/meson.build                 |   4 +-
 lib/librte_table/meson.build                 |   7 +-
 lib/meson.build                              |   3 +
 meson.build                                  |   6 +
 meson_options.txt                            |   2 +
 21 files changed, 112 insertions(+), 280 deletions(-)
 create mode 100755 buildtools/chkincs/gen_c_file_for_header.py
 create mode 100644 buildtools/chkincs/main.c
 create mode 100644 buildtools/chkincs/meson.build
 delete mode 100755 devtools/check-includes.sh
- clang is not happy when enabling the check:
$ meson configure $HOME/builds/build-clang-static -Dcheck_includes=true
$ devtools/test-meson-builds.sh
...
[362/464] Compiling C object
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_vdev.c.o
FAILED: buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_vdev.c.o
clang -Ibuildtools/chkincs/chkincs.p -Ibuildtools/chkincs
-I../../dpdk/buildtools/chkincs -Idrivers/bus/pci
-I../../dpdk/drivers/bus/pci -Idrivers/bus/vdev
-I../../dpdk/drivers/bus/vdev -I. -I../../dpdk -Iconfig
-I../../dpdk/config -Ilib/librte_eal/include
-I../../dpdk/lib/librte_eal/include -Ilib/librte_eal/linux/include
-I../../dpdk/lib/librte_eal/linux/include -Ilib/librte_eal/x86/include
-I../../dpdk/lib/librte_eal/x86/include -Ilib/librte_kvargs
-I../../dpdk/lib/librte_kvargs -Ilib/librte_metrics
-I../../dpdk/lib/librte_metrics -Ilib/librte_telemetry
-I../../dpdk/lib/librte_telemetry -Ilib/librte_eal/common
-I../../dpdk/lib/librte_eal/common -Ilib/librte_eal
-I../../dpdk/lib/librte_eal -Ilib/librte_ring
-I../../dpdk/lib/librte_ring -Ilib/librte_rcu
-I../../dpdk/lib/librte_rcu -Ilib/librte_mempool
-I../../dpdk/lib/librte_mempool -Ilib/librte_mbuf
-I../../dpdk/lib/librte_mbuf -Ilib/librte_net
-I../../dpdk/lib/librte_net -Ilib/librte_meter
-I../../dpdk/lib/librte_meter -Ilib/librte_ethdev
-I../../dpdk/lib/librte_ethdev -Ilib/librte_pci
-I../../dpdk/lib/librte_pci -Ilib/librte_cmdline
-I../../dpdk/lib/librte_cmdline -Ilib/librte_hash
-I../../dpdk/lib/librte_hash -Ilib/librte_timer
-I../../dpdk/lib/librte_timer -Ilib/librte_acl
-I../../dpdk/lib/librte_acl -Ilib/librte_bbdev
-I../../dpdk/lib/librte_bbdev -Ilib/librte_bitratestats
-I../../dpdk/lib/librte_bitratestats -Ilib/librte_cfgfile
-I../../dpdk/lib/librte_cfgfile -Ilib/librte_compressdev
-I../../dpdk/lib/librte_compressdev -Ilib/librte_cryptodev
-I../../dpdk/lib/librte_cryptodev -Ilib/librte_distributor
-I../../dpdk/lib/librte_distributor -Ilib/librte_efd
-I../../dpdk/lib/librte_efd -Ilib/librte_eventdev
-I../../dpdk/lib/librte_eventdev -Ilib/librte_gro
-I../../dpdk/lib/librte_gro -Ilib/librte_gso
-I../../dpdk/lib/librte_gso -Ilib/librte_ip_frag
-I../../dpdk/lib/librte_ip_frag -Ilib/librte_jobstats
-I../../dpdk/lib/librte_jobstats -Ilib/librte_kni
-I../../dpdk/lib/librte_kni -Ilib/librte_latencystats
-I../../dpdk/lib/librte_latencystats -Ilib/librte_lpm
-I../../dpdk/lib/librte_lpm -Ilib/librte_member
-I../../dpdk/lib/librte_member -Ilib/librte_power
-I../../dpdk/lib/librte_power -Ilib/librte_pdump
-I../../dpdk/lib/librte_pdump -Ilib/librte_rawdev
-I../../dpdk/lib/librte_rawdev -Ilib/librte_regexdev
-I../../dpdk/lib/librte_regexdev -Ilib/librte_rib
-I../../dpdk/lib/librte_rib -Ilib/librte_reorder
-I../../dpdk/lib/librte_reorder -Ilib/librte_sched
-I../../dpdk/lib/librte_sched -Ilib/librte_security
-I../../dpdk/lib/librte_security -Ilib/librte_stack
-I../../dpdk/lib/librte_stack -Ilib/librte_vhost
-I../../dpdk/lib/librte_vhost -Ilib/librte_ipsec
-I../../dpdk/lib/librte_ipsec -Ilib/librte_fib
-I../../dpdk/lib/librte_fib -Ilib/librte_port
-I../../dpdk/lib/librte_port -Ilib/librte_table
-I../../dpdk/lib/librte_table -Ilib/librte_pipeline
-I../../dpdk/lib/librte_pipeline -Ilib/librte_flow_classify
-I../../dpdk/lib/librte_flow_classify -Ilib/librte_bpf
-I../../dpdk/lib/librte_bpf -Ilib/librte_graph
-I../../dpdk/lib/librte_graph -Ilib/librte_node
-I../../dpdk/lib/librte_node
-I/home/dmarchan/intel-ipsec-mb/install/include -Xclang
-fcolor-diagnostics -pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch
-Werror -O2 -g -include rte_config.h -Wextra -Wcast-qual -Wdeprecated
-Wformat -Wformat-nonliteral -Wformat-security -Wmissing-declarations
-Wmissing-prototypes -Wnested-externs -Wold-style-definition
-Wpointer-arith -Wsign-compare -Wstrict-prototypes -Wundef
-Wwrite-strings -Wno-address-of-packed-member
-Wno-missing-field-initializers -D_GNU_SOURCE -march=native
-Wno-unused-function -DALLOW_EXPERIMENTAL_API -MD -MQ
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_vdev.c.o -MF
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_vdev.c.o.d -o
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_vdev.c.o -c
buildtools/chkincs/chkincs.p/rte_ethdev_vdev.c
In file included from buildtools/chkincs/chkincs.p/rte_ethdev_vdev.c:1:
In file included from
/home/dmarchan/dpdk/lib/librte_ethdev/rte_ethdev_vdev.h:12:
../../dpdk/lib/librte_ethdev/rte_ethdev_driver.h:964:1: error: unknown
attribute 'error' ignored [-Werror,-Wunknown-attributes]
__rte_internal
^
../../dpdk/lib/librte_eal/include/rte_compat.h:25:16: note: expanded
from macro '__rte_internal'
__attribute__((error("Symbol is not public ABI"), \
               ^
This looks to be a real issue with our header file - clang does not have an
"error" attribute. The closest equivalent I can see is "diagnose_if".
Indeed, it does trigger a build error, so it works as expected ;-).


On the header check itself, even if we find a way to properly tag
those symbols with the macro in rte_compat.h, the next issue is that
clang complains about such marked symbols without the
ALLOW_INTERNAL_API build flag.

FAILED: buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_pci.c.o
clang -Ibuildtools/chkincs/chkincs.p -Ibuildtools/chkincs
-I../../dpdk/buildtools/chkincs -Idrivers/bus/pci
-I../../dpdk/drivers/bus/pci -Idrivers/bus/vdev
-I../../dpdk/drivers/bus/vdev -I. -I../../dpdk -Iconfig
-I../../dpdk/config -Ilib/librte_eal/include
-I../../dpdk/lib/librte_eal/include -Ilib/librte_eal/linux/include
-I../../dpdk/lib/librte_eal/linux/include -Ilib/librte_eal/x86/include
-I../../dpdk/lib/librte_eal/x86/include -Ilib/librte_kvargs
-I../../dpdk/lib/librte_kvargs -Ilib/librte_metrics
-I../../dpdk/lib/librte_metrics -Ilib/librte_telemetry
-I../../dpdk/lib/librte_telemetry -Ilib/librte_eal/common
-I../../dpdk/lib/librte_eal/common -Ilib/librte_eal
-I../../dpdk/lib/librte_eal -Ilib/librte_ring
-I../../dpdk/lib/librte_ring -Ilib/librte_rcu
-I../../dpdk/lib/librte_rcu -Ilib/librte_mempool
-I../../dpdk/lib/librte_mempool -Ilib/librte_mbuf
-I../../dpdk/lib/librte_mbuf -Ilib/librte_net
-I../../dpdk/lib/librte_net -Ilib/librte_meter
-I../../dpdk/lib/librte_meter -Ilib/librte_ethdev
-I../../dpdk/lib/librte_ethdev -Ilib/librte_pci
-I../../dpdk/lib/librte_pci -Ilib/librte_cmdline
-I../../dpdk/lib/librte_cmdline -Ilib/librte_hash
-I../../dpdk/lib/librte_hash -Ilib/librte_timer
-I../../dpdk/lib/librte_timer -Ilib/librte_acl
-I../../dpdk/lib/librte_acl -Ilib/librte_bbdev
-I../../dpdk/lib/librte_bbdev -Ilib/librte_bitratestats
-I../../dpdk/lib/librte_bitratestats -Ilib/librte_cfgfile
-I../../dpdk/lib/librte_cfgfile -Ilib/librte_compressdev
-I../../dpdk/lib/librte_compressdev -Ilib/librte_cryptodev
-I../../dpdk/lib/librte_cryptodev -Ilib/librte_distributor
-I../../dpdk/lib/librte_distributor -Ilib/librte_efd
-I../../dpdk/lib/librte_efd -Ilib/librte_eventdev
-I../../dpdk/lib/librte_eventdev -Ilib/librte_gro
-I../../dpdk/lib/librte_gro -Ilib/librte_gso
-I../../dpdk/lib/librte_gso -Ilib/librte_ip_frag
-I../../dpdk/lib/librte_ip_frag -Ilib/librte_jobstats
-I../../dpdk/lib/librte_jobstats -Ilib/librte_kni
-I../../dpdk/lib/librte_kni -Ilib/librte_latencystats
-I../../dpdk/lib/librte_latencystats -Ilib/librte_lpm
-I../../dpdk/lib/librte_lpm -Ilib/librte_member
-I../../dpdk/lib/librte_member -Ilib/librte_power
-I../../dpdk/lib/librte_power -Ilib/librte_pdump
-I../../dpdk/lib/librte_pdump -Ilib/librte_rawdev
-I../../dpdk/lib/librte_rawdev -Ilib/librte_regexdev
-I../../dpdk/lib/librte_regexdev -Ilib/librte_rib
-I../../dpdk/lib/librte_rib -Ilib/librte_reorder
-I../../dpdk/lib/librte_reorder -Ilib/librte_sched
-I../../dpdk/lib/librte_sched -Ilib/librte_security
-I../../dpdk/lib/librte_security -Ilib/librte_stack
-I../../dpdk/lib/librte_stack -Ilib/librte_vhost
-I../../dpdk/lib/librte_vhost -Ilib/librte_ipsec
-I../../dpdk/lib/librte_ipsec -Ilib/librte_fib
-I../../dpdk/lib/librte_fib -Ilib/librte_port
-I../../dpdk/lib/librte_port -Ilib/librte_table
-I../../dpdk/lib/librte_table -Ilib/librte_pipeline
-I../../dpdk/lib/librte_pipeline -Ilib/librte_flow_classify
-I../../dpdk/lib/librte_flow_classify -Ilib/librte_bpf
-I../../dpdk/lib/librte_bpf -Ilib/librte_graph
-I../../dpdk/lib/librte_graph -Ilib/librte_node
-I../../dpdk/lib/librte_node
-I/home/dmarchan/intel-ipsec-mb/install/include -Xclang
-fcolor-diagnostics -pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch
-Werror -O2 -g -include rte_config.h -Wextra -Wcast-qual -Wdeprecated
-Wformat -Wformat-nonliteral -Wformat-security -Wmissing-declarations
-Wmissing-prototypes -Wnested-externs -Wold-style-definition
-Wpointer-arith -Wsign-compare -Wstrict-prototypes -Wundef
-Wwrite-strings -Wno-address-of-packed-member
-Wno-missing-field-initializers -D_GNU_SOURCE -march=native
-Wno-unused-function -DALLOW_EXPERIMENTAL_API -MD -MQ
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_pci.c.o -MF
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_pci.c.o.d -o
buildtools/chkincs/chkincs.p/meson-generated_rte_ethdev_pci.c.o -c
buildtools/chkincs/chkincs.p/rte_ethdev_pci.c
In file included from buildtools/chkincs/chkincs.p/rte_ethdev_pci.c:1:
/home/dmarchan/dpdk/lib/librte_ethdev/rte_ethdev_pci.h:86:13: error:
Symbol is not public ABI
                eth_dev = rte_eth_dev_allocate(name);
                          ^
../../dpdk/lib/librte_ethdev/rte_ethdev_driver.h:1003:1: note: from
'diagnose_if' attribute on 'rte_eth_dev_allocate':
__rte_internal
^~~~~~~~~~~~~~
../../dpdk/lib/librte_eal/include/rte_compat.h:30:16: note: expanded
from macro '__rte_internal'
__attribute__((diagnose_if(1, "Symbol is not public ABI", "error"), \
               ^           ~
[...]


gcc seems more lenient about this.


quoted
Therefore, I'd suggest we need to change compat.h to be something like:

  #if !defined ALLOW_INTERNAL_API && __has_attribute(error) /* For GCC */

  #define __rte_internal \
  __attribute__((error("Symbol is not public ABI"), \
  section(".text.internal")))

  #elif !defined ALLOW_INTERNAL_API && __has_attribute(diagnose_if) /* For clang */

  #define __rte_internal \
  __attribute__((diagnose_if(1, "Symbol is not public ABI", "error"), \
  section(".text.internal")))

  #else

  #define __rte_internal \
  __attribute__((section(".text.internal")))

  #endif

Any thoughts or suggestions for better alternatives here?
I'd rather leave a build error on an unknown attribute than silence
this check (which happens in your snippet, where it falls back to the
#else part).

Did you consider the deprecated() like for the experimental tag?
I've added the ALLOW_INTERNAL_API define to the build of these headers in
v4.
+Ferruh, Thomas

Removing the ALLOW_INTERNAL_API is probably a good idea, but it does indeed
throw up the errors with clang - but not gcc, which is strange. The
offending headers seem to be (initially):

* rte_ethdev_vdev.h
* rte_ethdev_pci.h

Are these public header files, or should they skip header checking - and
installation - as internal-only?

/Bruce
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help