[LTP] [PATCH] futex: skip futex_wake04.c if system not support huge pages

[Wanlong Gao]

On Mon, Nov 16, 2015 at 02:00:52PM +0800, Li Wang wrote:
> Hi,
> 
> On Mon, Nov 16, 2015 at 1:06 PM, Wanlong Gao <wanlong.gao@gmail.com> wrote:
> 
>     On Sun, Nov 15, 2015 at 04:41:00PM +0800, Li Wang wrote:
>     > Testcase fails on system which not support hugepages:
>     >
>     > futex_wake04    1  TBROK  :  safe_file_ops.c:155: The FILE '/proc/sys/vm/
>     nr_hugepages' ended prematurely at futex_wake04.c:74
>     > futex_wake04    2  TBROK  :  safe_file_ops.c:155: Remaining cases broken
>     >
>     > Skip the testcase cases with TCONF rather than failing with TBROK.
>     >
>     > Signed-off-by: Li Wang <liwang@redhat.com>
>     > ---
>     >  testcases/kernel/syscalls/futex/futex_wake04.c | 4 ++++
>     >  1 file changed, 4 insertions(+)
>     >
>     > diff --git a/testcases/kernel/syscalls/futex/futex_wake04.c b/testcases/
>     kernel/syscalls/futex/futex_wake04.c
>     > index dcefde8..2d6bd4c 100644
>     > --- a/testcases/kernel/syscalls/futex/futex_wake04.c
>     > +++ b/testcases/kernel/syscalls/futex/futex_wake04.c
>     > @@ -50,6 +50,7 @@
>     >
>     >  #define PATH_MEMINFO "/proc/meminfo"
>     >  #define PATH_NR_HUGEPAGES "/proc/sys/vm/nr_hugepages"
>     > +#define PATH_SYS_HUGEPAGES "/sys/kernel/mm/hugepages/"
> 
>     Why not use the original "/proc/sys/vm/nr_hugepages" to check the hugetlb
>     support but add a new one ?
> 
> 
> In my test system, there exist file "/proc/sys/vm/nr_hugepages" with normal
> permission, but reject any R/W operation.
> 
> So, if I use   if (access(PATH_NR_HUGEPAGES, F_OK) == -1),  It doesn't work.
> 
> # ll /proc/sys/vm/nr_hugepages
> -rw-r--r--. 1 root root 0 Nov 15 09:03 /proc/sys/vm/nr_hugepages
> 
> # cat /proc/sys/vm/nr_hugepages
> cat: write error: Bad address

Would you show your kernel version or investigate why this happens?
This should not exist if we disable the hugetlbfs in kernel config.

> 
> # cat /proc/meminfo
> MemTotal:        8663296 kB
> MemFree:         6637056 kB
> MemAvailable:    8151744 kB
> Buffers:            4160 kB
> Cached:          1504192 kB
> SwapCached:            0 kB
> Active:           946816 kB
> Inactive:         788480 kB
> Active(anon):     230592 kB
> Inactive(anon):     9472 kB
> Active(file):     716224 kB
> Inactive(file):   779008 kB
> Unevictable:           0 kB
> Mlocked:               0 kB
> SwapTotal:       4652992 kB
> SwapFree:        4652992 kB
> Dirty:                 0 kB
> Writeback:             0 kB
> AnonPages:        226944 kB
> Mapped:            51456 kB
> Shmem:             13120 kB
> Slab:             188032 kB
> SReclaimable:      63232 kB
> SUnreclaim:       124800 kB
> KernelStack:        2944 kB
> PageTables:         2176 kB
> NFS_Unstable:          0 kB
> Bounce:                0 kB
> WritebackTmp:          0 kB
> CommitLimit:     8984640 kB
> Committed_AS:     464064 kB
> VmallocTotal:   8589934592 kB
> VmallocUsed:       53056 kB
> VmallocChunk:   8589850624 kB
> HardwareCorrupted:     0 kB

> AnonHugePages:         0 kB

This tells that your kernel support THP.

Thanks,
Wanlong Gao

> 
> 
> --
> Regards,
> Li Wang
> Email: liwang@redhat.com