---Problem Description--- Valgrind is incorrectly modeling the PowerPC timebase register as 32-bit. Should be 64-bit. ---uname output--- Linux c650f07p23 4.11.0-42.el7a.ppc64le #1 SMP Mon Oct 9 12:00:22 EDT 2017 ppc64le ppc64le ppc64le GNU/Linux Machine Type = 8335-GTC ---Debugger--- A debugger is not configured ---Steps to Reproduce--- Compile the following example using "gcc -o tb tb.c" and execute. Without Valgrind, program will display timebase as 64-bit values. With Valgrind, timebase will be limited to 32-bit values and the 2nd timebase printf may appear to be lesser than the first timebase printf. #include <stdio.h> #include <sys/platform/ppc.h> int main(int argc, char** argv) { uint64_t tb = __ppc_get_timebase(); printf("timebase = %lx\n", tb); sleep(15); tb = __ppc_get_timebase(); printf("timebase = %lx\n", tb); return 0; } Contact Information = Tom Gooding / tgooding@us.ibm.com Userspace tool common name: valgrind The userspace tool has the following bit modes: 64-bit Userspace rpm: valgrind-3.12.0-9.el7_4.ppc64le Userspace tool obtained from project website: na *Additional Instructions for Tom Gooding / tgooding@us.ibm.com: -Attach ltrace and strace of userspace application. [reply] [-] Internal Only Comment 1 Thomas M. Gooding 2017-10-30 22:48:33 CDT output: bash-4.2$ ./tb timebase = 3be626e90262 timebase = 3be7f0ad4167 bash-4.2$ valgrind ./tb ==89099== Memcheck, a memory error detector ==89099== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al. ==89099== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info ==89099== Command: ./tb ==89099== timebase = 8ab00ec0 timebase = 552cacc9 ==89099== ==89099== HEAP SUMMARY: ==89099== in use at exit: 0 bytes in 0 blocks ==89099== total heap usage: 0 allocs, 0 frees, 0 bytes allocated ==89099== ==89099== All heap blocks were freed -- no leaks are possible ==89099== ==89099== For counts of detected and suppressed errors, rerun with: -v ==89099== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0) Issue reported by Thomas M. Gooding
Created attachment 108657 [details] Fix for reading the time base register
Patch committed. commit 6a55b1e82ccda3f0d663d2cc89eb543ae2d096bf Author: Carl Love <carll@us.ibm.com> Date: Tue Oct 31 13:45:28 2017 -0500 Fix access to time base register to return 64-bits.