xeno-test failed due to cond_destroy error

Fangsuo Wu tiger20081015 at gmail.com
Wed May 12 04:08:09 CEST 2021


yes, to be more accurate, the issue is found in the libc file under
gcc-linaro-arm-linux-gnueabihf-4.9-2014.08_linux/arm-linux-gnueabihf/libc/usr/include/pthread.h.

The glibc is accompanied with the gcc I downloaded from
https://releases.linaro.org/archive/14.08/components/toolchain/binaries/.

2021-05-11 23:10 GMT+08:00, Jan Kiszka <jan.kiszka at siemens.com>:
> On 11.05.21 12:37, Fangsuo Wu wrote:
>> Hi, the issue seems related to the gcc compiler I
>> used(gcc-linaro-arm-linux-gnueabihf-4.9-2014.08_linux).
>
> Huh, that is... well "matured".
>
>>
>> I added some log and found the failure was from below code, line 155:
>> pthread_cond_destroy
>>     -> cobalt_cond_autoinit_type:
>> 149 static int __attribute__((cold))
>> 150 >-------cobalt_cond_autoinit_type(const pthread_cond_t *cond)
>> 151 {
>> 152 >-------static const pthread_cond_t cond_initializer =
>> 153 >------->-------PTHREAD_COND_INITIALIZER;
>> 154
>> 155 >-------return memcmp(cond, &cond_initializer,
>> sizeof(cond_initializer)) == 0 ?
>> 156 >------->-------0 : -1;   //memcmp is not Zero
>> 157 }
>>
>> I dumped the content of pthread_cond_t  cond and cond_initializer. For
>> the latter one, all bytes were 0, but for cond variable, only the
>> first 44 bytes were 0, the last 4 bytes' value changed every time.
>>
>> I found the pthread_cond_t  and PTHREAD_COND_INITIALIZER definitions
>> in the GCC I used:
>>
>> #define PTHREAD_COND_INITIALIZER { { 0, 0, 0, 0, 0, (void *) 0, 0, 0}}
>> #define __SIZEOF_PTHREAD_COND_T 48
>>
>>  89 typedef union
>>  90 {
>>  91   struct
>>  92   {
>>  93     int __lock;
>>  94     unsigned int __futex;
>>  95     __extension__ unsigned long long int __total_seq;
>>  96     __extension__ unsigned long long int __wakeup_seq;
>>  97     __extension__ unsigned long long int __woken_seq;
>>  98     void *__mutex;
>>  99     unsigned int __nwaiters;
>> 100     unsigned int __broadcast_seq;
>> 101   } __data;
>> 102   char __size[__SIZEOF_PTHREAD_COND_T];
>> 103   __extension__ long long int __align;
>> 104 } pthread_cond_t;
>> 105
>>
>> The total size of pthread_cond_t.__size is 48. But
>> PTHREAD_COND_INITIALIZER only initializes the first 44 bytes, thus the
>> last 4 bytes' value becomes unpredictable. The issue was gone after I
>> made the below change:
>>
>>  197 //#define PTHREAD_COND_INITIALIZER { { 0, 0, 0, 0, 0, (void *) 0,
>> 0, 0}}
>>  198 #define PTHREAD_COND_INITIALIZER { .__size = {0}}
>>
>
> Err, those types should rather come from glibc, not [lib]gcc.
>
> Which glibc version are you using?
>
> Jan
>
>>
>>
>> 2021-05-10 17:40 GMT+08:00, Fangsuo Wu <tiger20081015 at gmail.com>:
>>> BTW, I just wrote an application which is exactly the same with
>>> autoinit_simple_conddestroy. And it can run successfully in my board.
>>>
>>>   1 #include <stdio.h>
>>>   2 #include <pthread.h>
>>>   3 int main(void)
>>>   4 {
>>>   5 >-------pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
>>>   6 >-------if(pthread_cond_destroy(&cond) == 0)
>>>   7 >------->-------printf("suc!\n");
>>>   8 >-------else
>>>   9 >------->-------printf("err!\n");
>>>  10 }
>>>
>>> sh-4.4# ./main
>>> suc!
>>>
>>>
>>> 2021-05-10 17:28 GMT+08:00, Fangsuo Wu <tiger20081015 at gmail.com>:
>>>> Jan,
>>>> I removed the CFLAGS and LDFLAGS, with configure command:
>>>>
>>>> ./configure --build=i686-pc-linux-gnu --host=arm-linux-gnueabihf
>>>> --with-core=cobalt --enable-smp --enable-lazy-setsched
>>>> --enable-debug=symbols
>>>>
>>>> But the issue still remains. I changed the failed test case as below,
>>>> the issue still exists.
>>>>
>>>> 226 static void autoinit_simple_conddestroy(void)
>>>> 227 {
>>>> 228 >-------pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
>>>> 229 #if 0
>>>> 230 >-------pthread_cond_t cond2 = PTHREAD_COND_INITIALIZER;
>>>> 231 >-------unsigned int invalmagic = ~0x86860505; //
>>>> ~COBALT_COND_MAGIC
>>>> 232
>>>> 233 >-------memcpy((char *)&cond2 + sizeof(cond2) - sizeof(invalmagic),
>>>> 234 >------->-------&invalmagic, sizeof(invalmagic));
>>>> 235
>>>> 236 >-------smokey_trace("%s", __func__);
>>>> 237 #endif
>>>> 238 >-------check("cond_destroy", cond_destroy(&cond), 0);
>>>> 239 //>-----check("cond_destroy invalid", cond_destroy(&cond2),
>>>> -EINVAL);
>>>> 240 }
>>>>
>>>> I'll try QEMU later to see if the issue also exits in QEMU.
>>>>
>>>> BTW, I saw some below warnings in compiling, do they have any
>>>> relationship with the issue?
>>>>   /bin/bash ../../../libtool   --mode=install /usr/bin/install -c
>>>> smokey_net_server '/home/data/nfs_test//usr/xenomai/bin'
>>>> libtool: warning: '../../../lib/cobalt/libcobalt.la' has not been
>>>> installed in '/usr/xenomai/lib'
>>>> libtool: warning: '../../../lib/cobalt/libmodechk.la' has not been
>>>> installed in '/usr/xenomai/lib'
>>>>
>>>>
>>>>
>>>>
>>>> 2021-05-10 15:35 GMT+08:00, Jan Kiszka <jan.kiszka at siemens.com>:
>>>>> On 10.05.21 09:20, Fangsuo Wu wrote:
>>>>>> Jan,
>>>>>> Thanks for your reply. The environment I used is listed below. BTW, I
>>>>>> can run latency test successfully.
>>>>>>
>>>>>> 1. The revision of Xenomai: xenomai-3.1.tar.bz2
>>>>>> 2. Soc: dual ARM cortex A7
>>>>>> 3. How I built application libraries:
>>>>>>     ./configure CFLAGS="-march=armv7-a -mfpu=vfp3"
>>>>>> LDFLAGS="-march=armv7-a -mfpu=vfp3"   --build=i686-pc-linux-gnu
>>>>>> --host=arm-linux-gnueabihf --with-core=cobalt --enable-smp
>>>>>> --enable-pshared
>>>>>>    make DESTDIR=/home/data/nfs_test/ install
>>>>>> 4. The kernel I used is 4.19 so I applied
>>>>>> ipipe-core-4.19.55-arm-5.patch, and manually enabled
>>>>>> CONFIG_IPIPE_ARM_KUSER_TSC. The full config file is:
>>>>>>
>>>>>
>>>>> OK - our qemu-armhf target [1] is multicore A7 as well. Do you see the
>>>>> problem in QEMU, too? Do any of the extra CFLAGS or LDFLAGS you pass
>>>>> play a role here? We compile in CI only with "--enable-smp
>>>>> --enable-lazy-setsched --enable-debug=symbols" - maybe
>>>>> "--enable-pshared"...
>>>>>
>>>>> Jan
>>>>>
>>>>> [1] https://source.denx.de/Xenomai/xenomai-images/-/jobs/265962#L387
>>>>>
>>>>> --
>>>>> Siemens AG, T RDA IOT
>>>>> Corporate Competence Center Embedded Linux
>>>>>
>>>>
>>>
>
> --
> Siemens AG, T RDA IOT
> Corporate Competence Center Embedded Linux
>



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