Fix sys_time() to get subtick correction from the new xtim

This is a Scott Wood patch against 2.6.3. He's shy, so I'm volunteering to represent him in public :-). The Change number and BUG number are TimeSys internal references.

Change 22531 by scott@scott-50 on 2004/01/22 15:30:22

Use gettimeofday() rather than xtime.tv_sec in sys_time(), since sys_stime() uses settimeofday() and thus subtracts the subtick correction from the new xtime.

Fixes BUG05331 Command line LTP test stime01 fails.

stime() used settimeofday(), but time() did not use
gettimeofday(). Since
settimeofday() subtracts out the current intra-tick correction,
and nsec
was 0 (since stime() only allows seconds), this resulted in xtime
being
slightly earlier than the time that was set. If time() had used
gettimeofday(),
the correction would have been applied, and everything would be fine. However, instead time just reads the current xtime.tv_sec, so if
time() is
called immediately after stime(), you'll usually get a value one
second earlier.

diff -puN kernel/arch/ia64/ia32/sys_ia32.c~fix-all-time-sys_time kernel/arch/ia64/ia32/sys_ia32.c
@@ -1678,10 +1678,11 @@ asmlinkage long

sys32_time (int *tloc)

{
       int i;

+ struct timeval tv;
+
+ do_gettimeofday(&tv);
+ i = tv.tv_sec;

- /* SMP: This is fairly trivial. We grab CURRENT_TIME and
- stuff it to user space. No side effects */

-       i = get_seconds();
       if (tloc) {
               if (put_user(i, tloc))
                       i = -EFAULT;

diff -puN -L kernel/arch/ia64/ia32/sys_ia32.c-orig /dev/null /dev/null

diff -puN kernel/arch/parisc/kernel/sys_parisc32.c~fix-all-time-sys_time kernel/arch/parisc/kernel/sys_parisc32.c
@@ -388,14 +388,16 @@ static inline long get_ts32(struct times
 

asmlinkage long sys32_time(compat_time_t *tloc)
{
- time_t now = get_seconds();
- compat_time_t now32 = now;
+ struct timeval tv;

- if (tloc)
- if (put_user(now32, tloc))
- now32 = -EFAULT;
+ do_gettimeofday(&tv);
+ compat_time_t now32 = tv.tv_sec;

- return now32;
+ if (tloc)
+ if (put_user(now32, tloc))
+ now32 = -EFAULT;
+
+ return now32;
}

asmlinkage int
diff -puN -L kernel/arch/parisc/kernel/sys_parisc32.c-orig /dev/null /dev/null

diff -puN kernel/arch/x86_64/ia32/sys_ia32.c~fix-all-time-sys_time kernel/arch/x86_64/ia32/sys_ia32.c
@@ -833,10 +833,11 @@ sys32_writev(int fd, struct compat_iovec

asmlinkage long sys32_time(int * tloc)

{
       int i;

+ struct timeval tv;
+
+ do_gettimeofday(&tv);
+ i = tv.tv_sec;

- /* SMP: This is fairly trivial. We grab CURRENT_TIME and
- stuff it to user space. No side effects */

-       i = get_seconds();
       if (tloc) {
               if (put_user(i,tloc))
                       i = -EFAULT;

diff -puN -L kernel/arch/x86_64/ia32/sys_ia32.c-orig /dev/null /dev/null

diff -puN kernel/kernel/time.c~fix-all-time-sys_time kernel/kernel/time.c
@@ -51,10 +51,11 @@ EXPORT_SYMBOL(sys_tz);

asmlinkage long sys_time(int * tloc)

{
       int i;

+ struct timeval tv;
+
+ do_gettimeofday(&tv);
+ i = tv.tv_sec;

- /* SMP: This is fairly trivial. We grab CURRENT_TIME and
- stuff it to user space. No side effects */

-       i = get_seconds();
       if (tloc) {
               if (put_user(i,tloc))
                       i = -EFAULT;

diff -puN -L kernel/kernel/time.c-orig /dev/null /dev/null

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