Lanzhiguan Huang via llvm-dev
2021-Mar-05 07:31 UTC
[llvm-dev] How to generate the perfscript file for llvm-profgen
Hi, I'm really interested in the new CSSPGO tool, can anyone give me some more detailed instructions about how to generate the perfscript file it needs, I tried to first use "perf record -e xxx -b ..." to generate a perf.data file and then use "perf script" to dump all the text into a perfscript file, but it seems to be different from the perfscript under the llvm/test/tools/llvm-profgen/Inputs directory. Lanzhiguan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20210305/951bba36/attachment-0001.html>
Wenlei He via llvm-dev
2021-Mar-05 21:47 UTC
[llvm-dev] How to generate the perfscript file for llvm-profgen
Thanks for trying it out! To get context-sensitive profile, you will need to collect perf data with both LBR and stack sample enabled. We use something like this: perf record -g --call-graph fp -e br_inst_retired.near_taken:uppp -c 16009 -b -o <perf_data_output> <command_to_profile> Here’s the perf script command to extract both LBR and stack sample: perf script -F ip,brstack -i <perf_data_output> --show-mmap-event &> <perf_script_output> Let us know how it works. Thanks, Wenlei From: llvm-dev <llvm-dev-bounces at lists.llvm.org> on behalf of Lanzhiguan Huang via llvm-dev <llvm-dev at lists.llvm.org> Date: Thursday, March 4, 2021 at 11:32 PM To: LLVM Developers Mailing List <llvm-dev at lists.llvm.org> Subject: [llvm-dev] How to generate the perfscript file for llvm-profgen Hi, I'm really interested in the new CSSPGO tool, can anyone give me some more detailed instructions about how to generate the perfscript file it needs, I tried to first use "perf record -e xxx -b ..." to generate a perf.data file and then use "perf script" to dump all the text into a perfscript file, but it seems to be different from the perfscript under the llvm/test/tools/llvm-profgen/Inputs directory. Lanzhiguan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20210305/ba5fd71c/attachment.html>