[PATCH] tools/power turbostat: call pread64 in kernel directly

From: Liwei Song
Date: Fri Jul 17 2020 - 02:09:47 EST


with 32-bit rootfs, the offset may out of range when set it
to 0xc0010299, define it as "unsigned long long" type and
call pread64 directly in kernel.

Signed-off-by: Liwei Song <liwei.song@xxxxxxxxxxxxx>
---
tools/power/x86/turbostat/turbostat.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index 33b370865d16..4c5cdfcb5721 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -33,6 +33,7 @@
#include <sys/capability.h>
#include <errno.h>
#include <math.h>
+#include <sys/syscall.h>

char *proc_stat = "/proc/stat";
FILE *outf;
@@ -381,11 +382,11 @@ int get_msr_fd(int cpu)
return fd;
}

-int get_msr(int cpu, off_t offset, unsigned long long *msr)
+int get_msr(int cpu, unsigned long long offset, unsigned long long *msr)
{
ssize_t retval;

- retval = pread(get_msr_fd(cpu), msr, sizeof(*msr), offset);
+ retval = syscall(SYS_pread64, get_msr_fd(cpu), msr, sizeof(*msr), offset);

if (retval != sizeof *msr)
err(-1, "cpu%d: msr offset 0x%llx read failed", cpu, (unsigned long long)offset);
--
2.17.1