The regs_query_register_offset() helper function converts register name like "%r0" to an offset of a register in user_pt_regs It is required by the BPF prologue generator.
The user_pt_regs structure was recently added to "asm/ptrace.h". Hence, update tools/perf/check-headers.sh to keep the header file in sync with kernel changes.
Suggested-by: Thomas Richter tmricht@linux.vnet.ibm.com Signed-off-by: Hendrik Brueckner brueckner@linux.vnet.ibm.com Reviewed-and-tested-by: Thomas Richter tmricht@linux.vnet.ibm.com Cc: Arnaldo Carvalho de Melo acme@kernel.org Cc: Jiri Olsa jolsa@redhat.com Cc: Heiko Carstens heiko.carstens@de.ibm.com --- tools/perf/arch/s390/Makefile | 1 + tools/perf/arch/s390/util/dwarf-regs.c | 32 +++++++++++++++++++++++++++++--- tools/perf/check-headers.sh | 1 + 3 files changed, 31 insertions(+), 3 deletions(-)
diff --git a/tools/perf/arch/s390/Makefile b/tools/perf/arch/s390/Makefile index 21322e0..09ba923 100644 --- a/tools/perf/arch/s390/Makefile +++ b/tools/perf/arch/s390/Makefile @@ -2,3 +2,4 @@ ifndef NO_DWARF PERF_HAVE_DWARF_REGS := 1 endif HAVE_KVM_STAT_SUPPORT := 1 +PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1 diff --git a/tools/perf/arch/s390/util/dwarf-regs.c b/tools/perf/arch/s390/util/dwarf-regs.c index f47576c..a8ace5c 100644 --- a/tools/perf/arch/s390/util/dwarf-regs.c +++ b/tools/perf/arch/s390/util/dwarf-regs.c @@ -2,17 +2,43 @@ /* * Mapping of DWARF debug register numbers into register names. * - * Copyright IBM Corp. 2010 - * Author(s): Heiko Carstens heiko.carstens@de.ibm.com, + * Copyright IBM Corp. 2010, 2017 + * Author(s): Heiko Carstens heiko.carstens@de.ibm.com, + * Hendrik Brueckner brueckner@linux.vnet.ibm.com * */
+#include <errno.h> #include <stddef.h> -#include <dwarf-regs.h> +#include <stdlib.h> #include <linux/kernel.h> +#include <asm/ptrace.h> +#include <string.h> +#include <dwarf-regs.h> #include "dwarf-regs-table.h"
const char *get_arch_regstr(unsigned int n) { return (n >= ARRAY_SIZE(s390_dwarf_regs)) ? NULL : s390_dwarf_regs[n]; } + +/* + * Convert the register name into an offset to struct pt_regs (kernel). + * This is required by the BPF prologue generator. The BPF + * program is called in the BPF overflow handler in the perf + * core. + */ +int regs_query_register_offset(const char *name) +{ + unsigned long gpr; + + if (!name || strncmp(name, "%r", 2)) + return -EINVAL; + + errno = 0; + gpr = strtoul(name + 2, NULL, 10); + if (errno || gpr >= 16) + return -EINVAL; + + return offsetof(user_pt_regs, gprs) + 8 * gpr; +} diff --git a/tools/perf/check-headers.sh b/tools/perf/check-headers.sh index 77406d2..6db9d80 100755 --- a/tools/perf/check-headers.sh +++ b/tools/perf/check-headers.sh @@ -30,6 +30,7 @@ arch/x86/include/uapi/asm/vmx.h arch/powerpc/include/uapi/asm/kvm.h arch/s390/include/uapi/asm/kvm.h arch/s390/include/uapi/asm/kvm_perf.h +arch/s390/include/uapi/asm/ptrace.h arch/s390/include/uapi/asm/sie.h arch/arm/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h