[Openmp-dev] Segmentation fault libomptarget.so
Joel E. Denny via Openmp-dev
openmp-dev at lists.llvm.org
Wed Feb 13 14:13:40 PST 2019
Hi Talita,
What does ldd show for your executable? Is it linked to the libomp.so
you built? Or is it linked to something like libomp.so.5 in a system
directory?
Joel
On Wed, Feb 13, 2019 at 5:09 PM Talita Perciano via Openmp-dev
<openmp-dev at lists.llvm.org> wrote:
>
> Hi Kelvin,
>
> I see... in my case I used the clang 7 I compiled to build the openmp runtime. OS info:
>
> Ubuntu
> VERSION="16.04.5 LTS (Xenial Xerus)"
> Kernel: 4.4.0-141-generic
>
> I could try rebuilding the openmp runtime with gcc instead. Which gcc version did you use?
>
> Thanks,
> Talita
>
> On Wed, Feb 13, 2019 at 2:02 PM Kelvin Li <kli at ca.ibm.com> wrote:
>>
>> I tried it with the 7.0 source as your described in the attachment. I did not encounter the problem. The only difference in my openmp runtime build is to use gcc on the system instead of clang. Which version of clang did you use to build openmp runtime? Which OS is the build on?
>>
>> I assume that you updated the example program based on Alexey's suggestion and still get the seg fault.
>>
>> Kelvin
>>
>>
>>
>>
>> From: Talita Perciano via Openmp-dev <openmp-dev at lists.llvm.org>
>> To: Alexey Bataev <a.bataev at outlook.com>
>> Cc: Openmp-dev <openmp-dev-bounces at lists.llvm.org>, "openmp-dev at lists.llvm.org" <openmp-dev at lists.llvm.org>
>> Date: 2019/02/13 04:53 PM
>> Subject: Re: [Openmp-dev] Segmentation fault libomptarget.so
>> Sent by: "Openmp-dev" <openmp-dev-bounces at lists.llvm.org>
>> ________________________________
>>
>>
>>
>> No worries! Thanks so much!
>>
>> Talita
>>
>> On Wed, Feb 13, 2019 at 1:51 PM Alexey Bataev <a.bataev at outlook.com> wrote:
>> Hi Talita, had no time today, will look at it tomorrow, sorry.
>>
>> Best regards,
>> Alexey Bataev
>>
>> 13 февр. 2019 г., в 16:50, Talita Perciano <TPerciano at lbl.gov> написал(а):
>>
>> Hi,
>>
>> Did any of you guys have the chance to take a look at this?
>>
>> Thanks!
>> Talita
>>
>> On Tue, Feb 12, 2019 at 2:18 PM Talita Perciano <TPerciano at lbl.gov> wrote:
>> Hi,
>>
>> I'm attaching the cmake logs for both llvm and openmp.
>>
>> Thanks,
>> Talita
>>
>> On Tue, Feb 12, 2019 at 2:00 PM Alexey Bataev <a.bataev at outlook.com> wrote:
>> Yes, seems to me something wrong either with the compiler, or the way it is used. Need the compilation line, logs, error report.
>>
>> Best regards,
>> Alexey Bataev
>>
>> 12 февр. 2019 г., в 16:58, Gheorghe-Teod Bercea <Gheorghe-Teod.Bercea at ibm.com> написал(а):
>>
>> This fixed it for me:
>>
>> #pragma omp target map(tofrom: y[:n]) map(to:x[:n])
>> #pragma omp parallel for
>> for (int i = 0; i < n; i++)
>> y[i] += a * x[i];
>>
>> --Doru
>>
>>
>>
>>
>> From: Talita Perciano via Openmp-dev <openmp-dev at lists.llvm.org>
>> To: Alexey Bataev <a.bataev at outlook.com>
>> Cc: "openmp-dev at lists.llvm.org" <openmp-dev at lists.llvm.org>
>> Date: 02/12/2019 04:45 PM
>> Subject: Re: [Openmp-dev] Segmentation fault libomptarget.so
>> Sent by: "Openmp-dev" <openmp-dev-bounces at lists.llvm.org>
>> ________________________________
>>
>>
>>
>> Tried all the above... still segfault on my end. BTW, I don't know if that's relevant but I'm using cuda 9.2.
>>
>> On Tue, Feb 12, 2019 at 1:42 PM Alexey Bataev <a.bataev at outlook.com> wrote:
>> Tried your example with my correction,
>>
>> $./a.out 1000
>> Here
>>
>> min = 0.000047, max = 0.999994, avg = 0.504811
>>
>> $
>>
>> -------------
>> Best regards,
>> Alexey Bataev
>> 12.02.2019 16:38, Talita Perciano пишет:
>> Thanks for your quick response Alexey. I've just tried what you suggested and I'm still getting the same error.
>>
>> Best,
>> Talita
>>
>> On Tue, Feb 12, 2019 at 1:36 PM Alexey Bataev <a.bataev at outlook.com> wrote:
>> Try to modify target pragma this way
>>
>> #pragma omp target map(from: x[:n]) map(tofrom:y[:n])
>>
>> -------------
>> Best regards,
>> Alexey Bataev
>> 12.02.2019 16:33, Talita Perciano via Openmp-dev пишет:
>> Hi,
>>
>> I'm trying openmp offloading to gpu and I'm getting a segfault when trying to run a test code. I followed the instructions explained herehttps://www.hahnjo.de/blog/2018/10/08/clang-7.0-openmp-offloading-nvidia.html.
>>
>> Here is the piece of code I'm trying to run:
>>
>> #include <malloc.h>
>> #include <stdio.h>
>> #include <stdlib.h>
>>
>> int main(int argc, char* argv[])
>> {
>> if (argc != 2)
>> {
>> printf("Usage: %s \n", argv[0]);
>> return 0;
>> }
>>
>> int n = atoi(argv[1]);
>>
>> double* x = (double*)malloc(sizeof(double) * n);
>> double* y = (double*)malloc(sizeof(double) * n);
>>
>> double idrandmax = 1.0 / RAND_MAX;
>> double a = idrandmax * rand();
>> for (int i = 0; i < n; i++)
>> {
>> x[i] = idrandmax * rand();
>> y[i] = idrandmax * rand();
>> }
>> printf("Here\n\n");
>> #pragma omp target
>> #pragma omp parallel for
>> {
>> for (int i = 0; i < n; i++)
>> y[i] += a * x[i];
>> }
>>
>> double avg = 0.0, min = y[0], max = y[0];
>> for (int i = 0; i < n; i++)
>> {
>> avg += y[i];
>> if (y[i] > max) max = y[i];
>> if (y[i] < min) min = y[i];
>> }
>>
>> printf("min = %f, max = %f, avg = %f\n", min, max, avg / n);
>>
>> free(x);
>> free(y);
>>
>> return 0;
>> }
>>
>> I'm compiling the code like this: clang -fopenmp -fopenmp-targets=nvptx64 -O2 example.c
>> When I run I get a Segmentation fault immediately.
>>
>> Any thoughts?
>>
>> Thanks!
>> Talita
>>
>>
>> _______________________________________________
>> Openmp-dev mailing list
>> Openmp-dev at lists.llvm.org
>> https://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev
>>
>>
>>
>> --
>> Dr. Talita Perciano
>> Research Scientist - CRD, Lawrence Berkeley National Laboratory
>> Data Analytics & Visualization Group
>> Center for Advanced Mathematics for Energy Research Applications
>> One Cyclotron Road
>> Berkeley, CA 94720
>> 059-3034B M/S 59R3103
>> Work: (510) 486-5060
>> tperciano at lbl.gov
>> http://tperciano.wixsite.com/home
>>
>>
>> --
>> Dr. Talita Perciano
>> Research Scientist - CRD, Lawrence Berkeley National Laboratory
>> Data Analytics & Visualization Group
>> Center for Advanced Mathematics for Energy Research Applications
>> One Cyclotron Road
>> Berkeley, CA 94720
>> 059-3034B M/S 59R3103
>> Work: (510) 486-5060
>> tperciano at lbl.gov
>> http://tperciano.wixsite.com/home_______________________________________________
>> Openmp-dev mailing list
>> Openmp-dev at lists.llvm.org
>> https://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev
>>
>>
>>
>>
>> --
>> Dr. Talita Perciano
>> Research Scientist - CRD, Lawrence Berkeley National Laboratory
>> Data Analytics & Visualization Group
>> Center for Advanced Mathematics for Energy Research Applications
>> One Cyclotron Road
>> Berkeley, CA 94720
>> 059-3034B M/S 59R3103
>> Work: (510) 486-5060
>> tperciano at lbl.gov
>> http://tperciano.wixsite.com/home
>>
>>
>>
>> --
>> Dr. Talita Perciano
>> Research Scientist - CRD, Lawrence Berkeley National Laboratory
>> Data Analytics & Visualization Group
>> Center for Advanced Mathematics for Energy Research Applications
>> One Cyclotron Road
>> Berkeley, CA 94720
>> 059-3034B M/S 59R3103
>> Work: (510) 486-5060
>> tperciano at lbl.gov
>> http://tperciano.wixsite.com/home_______________________________________________
>> Openmp-dev mailing list
>> Openmp-dev at lists.llvm.org
>> https://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev
>>
>>
>>
>
>
> --
> Dr. Talita Perciano
> Research Scientist - CRD, Lawrence Berkeley National Laboratory
> Data Analytics & Visualization Group
> Center for Advanced Mathematics for Energy Research Applications
> One Cyclotron Road
> Berkeley, CA 94720
> 059-3034B M/S 59R3103
> Work: (510) 486-5060
> tperciano at lbl.gov
> http://tperciano.wixsite.com/home
> _______________________________________________
> Openmp-dev mailing list
> Openmp-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/openmp-dev
More information about the Openmp-dev
mailing list