perf build: Fix broken feature check for libtracefs due to external lib changes

The perf build process auto-detects features and packages already installed for its build. This is done in directory tools/build/feature. This directory contains small sample programs. When they successfully compile the necessary prereqs in form of libraries and header files are present. Such a check is also done for libtracefs. And this check fails: Output before: # rm -f test-libtracefs.bin; make test-libtracefs.bin gcc -MD -Wall -Werror -o test-libtracefs.bin test-libtracefs.c \ > test-libtracefs.make.output 2>&1 -ltracefs make: *** [Makefile:211: test-libtracefs.bin] Error 1 # cat test-libtracefs.make.output In file included from test-libtracefs.c:2: /usr/include/tracefs/tracefs.h:11:10: fatal error: \ event-parse.h: No such file or directory 11 | #include <event-parse.h> | ^~~~~~~~~~~~~~~ compilation terminated. # The root cause of this compile error is commit 880885d9c22e ("libtracefs: Remove "traceevent/" from referencing libtraceevent headers") in the libtracefs project hosted here: https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/ That mentioned patch removes the traceevent/ directory name from the include statement, causing the file not to be included even when the libtraceevent-devel package is installed. This package contains the file referred to in tracefs/tracefs.h: # rpm -ql libtraceevent-devel /usr/include/traceevent /usr/include/traceevent/event-parse.h <----- here /usr/include/traceevent/event-utils.h /usr/include/traceevent/kbuffer.h /usr/include/traceevent/trace-seq.h /usr/lib64/libtraceevent.so /usr/lib64/pkgconfig/libtraceevent.pc # With this patch the compile succeeds. Output after: # rm -f test-libtracefs.bin; make test-libtracefs.bin gcc -MD -Wall -Werror -o test-libtracefs.bin test-libtracefs.c \ > test-libtracefs.make.output 2>&1 -I/usr/include/traceevent -ltracefs # Committer testing: $ make -k BUILD_BPF_SKEL=1 CORESIGHT=1 O=/tmp/build/perf-tools -C tools/perf install-bin Before: $ cat /tmp/build/perf-tools/feature/test-libtracefs.make.output In file included from test-libtracefs.c:2: /usr/include/tracefs/tracefs.h:11:10: fatal error: event-parse.h: No such file or directory 11 | #include <event-parse.h> | ^~~~~~~~~~~~~~~ compilation terminated. $ $ grep -i tracefs /tmp/build/perf-tools/FEATURE-DUMP feature-libtracefs=0 $ After: $ cat /tmp/build/perf-tools/feature/test-libtracefs.make.output $ $ grep -i tracefs /tmp/build/perf-tools/FEATURE-DUMP feature-libtracefs=1 $

TRThomas Richter committed 3 years ago