Hi Maciej,
On 9/12/2023 10:59 PM, Maciej Wieczór-Retman wrote:
On 2023-09-12 at 09:00:28 -0700, Reinette Chatre wrote:
Hi Maciej,
On 9/11/2023 11:32 PM, Maciej Wieczór-Retman wrote:
On 2023-09-11 at 09:59:06 -0700, Reinette Chatre wrote:
Hi Maciej, When I build the tests with this applied I encounter the following:
resctrlfs.c: In function ‘write_schemata’: resctrlfs.c:475:14: warning: implicit declaration of function ‘open’; did you mean ‘popen’? [-Wimplicit-function-declaration] 475 | fd = open(controlgroup, O_WRONLY); | ^~~~ | popen resctrlfs.c:475:33: error: ‘O_WRONLY’ undeclared (first use in this function) 475 | fd = open(controlgroup, O_WRONLY); | ^~~~~~~~ resctrlfs.c:475:33: note: each undeclared identifier is reported only once for each function it appears in
Hmm, that's odd. How do you build the tests?
I applied this series on top of kselftest repo's "next" branch.
I use a separate build directory and first ran "make headers". After that, $ make O=<build dir> -C tools/testing/selftests/resctrl
I do the same, just without the build directory, but that shouldn't matter here I guess.
I use "make -C tools/testing/selftests/resctrl" while in the root kernel source directory. I tried to get the same error you experienced by compiling some dummy test program with "open" and "O_WRONLY". From the experiment I found that the "resctrl.h" header provides the declarations that are causing your errors.
From what I can tell resctrl.h does not include fcntl.h that provides what is needed.
I found out you can run "gcc -M <file>" and it will recursively tell you what headers are including other headers.
Using this I found that "resctrl.h" includes <sys/mount.h> which in turn includes <fcntl.h> out of /usr/include/sys directory. Is that also the case on your system?
No. The test system I used is running glibc 2.35 and it seems that including fcntl.h was added to sys/mount.h in 2.36. See glibc commit 78a408ee7ba0 ("linux: Add open_tree")
Generally we should avoid indirect inclusions and here I think certainly so since it cannot be guaranteed that fcntl.h would be available via sys/mount.h.
Reinette