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Functions are not displayed in Hotspot analysis

Ma_Wenqi
Beginner
379 Views
I am a newer to vtune . Currently,I try to do the Hotspot analysis for the x264 source code using the vtune for linux.Howerver, after the analysis has done ,the hot functions are not displayed ,as discribled in the fig1.



but when i test the sampling codes ,it works well ,as discribled bellow.



furthermore , i have also succeeded in finding the hot functions of x264 code by using vtune for windows with the vs2010,so i think my code is ok. Now i want to know why the functions cannot be displayed using the vtune for linux?
ps.
i use gcc -g -O2 as the gcc option and sometimes there is a warning "Symbol file is not found. The call stack passing through the module [vdso] may be incorrect"
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Vladimir_T_Intel
Moderator
379 Views
Hi,
Would you please update the images in your post - it's not visible.
Which version/build of VTune you were using?
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Ma_Wenqi
Beginner
379 Views
Thank you for noticing me .
The version is vtune for linux 2011 .
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Ma_Wenqi
Beginner
379 Views
Thanks for these who help me.I have sloved this problem.
The answer is simple,just because the symbol information is deleted when compiled.
In the configure file ,the -s option was used which makes the symbol information was deleted.

CFLAGS= -Wshadow -O2 -ffast-math -Wall -I. -march=i686 -mfpmath=sse -msse -std=gnu99 -s -fno-tree-vectorize
LDFLAGS= -lm -lpthread -s

so just delete the -s option ,there will be symbol information adding to the binarary execute file.And then we will see the hot functions.
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Vladimir_T_Intel
Moderator
379 Views
Right.
-s linker option removes all symbol table and relocation information from the executable.
Thank you.
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