This changes the select and pselect system calls to use the
new schedule_timeout_hr function. Since many applications
use the select function instead of nanosleep, this provides
a higher resolution sleep to them.

BUG: the same needs to be done for the compat syscalls, the
current patch breaks building on 64 bit machines.

Signed-off-by: Arnd Bergmann <[EMAIL PROTECTED]>

Index: linux-cg/fs/select.c
===================================================================
--- linux-cg.orig/fs/select.c
+++ linux-cg/fs/select.c
@@ -189,7 +189,7 @@ get_max:
 #define POLLOUT_SET (POLLWRBAND | POLLWRNORM | POLLOUT | POLLERR)
 #define POLLEX_SET (POLLPRI)
 
-int do_select(int n, fd_set_bits *fds, s64 *timeout)
+int do_select(int n, fd_set_bits *fds, ktime_t *timeout)
 {
        struct poll_wqueues table;
        poll_table *wait;
@@ -205,12 +205,11 @@ int do_select(int n, fd_set_bits *fds, s
 
        poll_initwait(&table);
        wait = &table.pt;
-       if (!*timeout)
+       if (timeout && !timeout->tv64)
                wait = NULL;
        retval = 0;
        for (;;) {
                unsigned long *rinp, *routp, *rexp, *inp, *outp, *exp;
-               long __timeout;
 
                set_current_state(TASK_INTERRUPTIBLE);
 
@@ -266,27 +265,19 @@ int do_select(int n, fd_set_bits *fds, s
                                *rexp = res_ex;
                }
                wait = NULL;
-               if (retval || !*timeout || signal_pending(current))
+               if (retval || (timeout && !timeout->tv64)
+                   || signal_pending(current))
                        break;
                if(table.error) {
                        retval = table.error;
                        break;
                }
 
-               if (*timeout < 0) {
+               if (!timeout || timeout->tv64 < 0)
                        /* Wait indefinitely */
-                       __timeout = MAX_SCHEDULE_TIMEOUT;
-               } else if (unlikely(*timeout >= (s64)MAX_SCHEDULE_TIMEOUT - 1)) 
{
-                       /* Wait for longer than MAX_SCHEDULE_TIMEOUT. Do it in 
a loop */
-                       __timeout = MAX_SCHEDULE_TIMEOUT - 1;
-                       *timeout -= __timeout;
-               } else {
-                       __timeout = *timeout;
-                       *timeout = 0;
-               }
-               __timeout = schedule_timeout(__timeout);
-               if (*timeout >= 0)
-                       *timeout += __timeout;
+                       schedule();
+               else
+                       *timeout = schedule_timeout_hr(*timeout);
        }
        __set_current_state(TASK_RUNNING);
 
@@ -307,7 +298,7 @@ int do_select(int n, fd_set_bits *fds, s
        ((unsigned long) (MAX_SCHEDULE_TIMEOUT / HZ)-1)
 
 static int core_sys_select(int n, fd_set __user *inp, fd_set __user *outp,
-                          fd_set __user *exp, s64 *timeout)
+                          fd_set __user *exp, ktime_t *timeout)
 {
        fd_set_bits fds;
        void *bits;
@@ -384,7 +375,7 @@ out_nofds:
 asmlinkage long sys_select(int n, fd_set __user *inp, fd_set __user *outp,
                        fd_set __user *exp, struct timeval __user *tvp)
 {
-       s64 timeout = -1;
+       ktime_t timeout, *timeoutp = NULL;
        struct timeval tv;
        int ret;
 
@@ -395,24 +386,20 @@ asmlinkage long sys_select(int n, fd_set
                if (tv.tv_sec < 0 || tv.tv_usec < 0)
                        return -EINVAL;
 
+               timeout = timeval_to_ktime(tv);
                /* Cast to u64 to make GCC stop complaining */
-               if ((u64)tv.tv_sec >= (u64)MAX_INT64_SECONDS)
-                       timeout = -1;   /* infinite */
-               else {
-                       timeout = ROUND_UP(tv.tv_usec, USEC_PER_SEC/HZ);
-                       timeout += tv.tv_sec * HZ;
-               }
+               if ((u64)tv.tv_sec < (u64)MAX_INT64_SECONDS)
+                       timeoutp = &timeout;
        }
 
-       ret = core_sys_select(n, inp, outp, exp, &timeout);
+       ret = core_sys_select(n, inp, outp, exp, timeoutp);
 
        if (tvp) {
                struct timeval rtv;
 
                if (current->personality & STICKY_TIMEOUTS)
                        goto sticky;
-               rtv.tv_usec = jiffies_to_usecs(do_div((*(u64*)&timeout), HZ));
-               rtv.tv_sec = timeout;
+               rtv = ktime_to_timeval(timeout);
                if (timeval_compare(&rtv, &tv) >= 0)
                        rtv = tv;
                if (copy_to_user(tvp, &rtv, sizeof(rtv))) {
@@ -438,7 +425,7 @@ asmlinkage long sys_pselect7(int n, fd_s
                fd_set __user *exp, struct timespec __user *tsp,
                const sigset_t __user *sigmask, size_t sigsetsize)
 {
-       s64 timeout = MAX_SCHEDULE_TIMEOUT;
+       ktime_t timeout, *timeoutp = NULL;
        sigset_t ksigmask, sigsaved;
        struct timespec ts;
        int ret;
@@ -450,13 +437,11 @@ asmlinkage long sys_pselect7(int n, fd_s
                if (ts.tv_sec < 0 || ts.tv_nsec < 0)
                        return -EINVAL;
 
+               timeout = timespec_to_ktime(ts);
+
                /* Cast to u64 to make GCC stop complaining */
-               if ((u64)ts.tv_sec >= (u64)MAX_INT64_SECONDS)
-                       timeout = -1;   /* infinite */
-               else {
-                       timeout = ROUND_UP(ts.tv_nsec, NSEC_PER_SEC/HZ);
-                       timeout += ts.tv_sec * HZ;
-               }
+               if ((u64)ts.tv_sec < (u64)MAX_INT64_SECONDS)
+                       timeoutp = &timeout;
        }
 
        if (sigmask) {
@@ -470,16 +455,15 @@ asmlinkage long sys_pselect7(int n, fd_s
                sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved);
        }
 
-       ret = core_sys_select(n, inp, outp, exp, &timeout);
+       ret = core_sys_select(n, inp, outp, exp, timeoutp);
 
        if (tsp) {
                struct timespec rts;
 
                if (current->personality & STICKY_TIMEOUTS)
                        goto sticky;
-               rts.tv_nsec = jiffies_to_usecs(do_div((*(u64*)&timeout), HZ)) *
-                                               1000;
-               rts.tv_sec = timeout;
+
+               rts = ktime_to_timespec(timeout);
                if (timespec_compare(&rts, &ts) >= 0)
                        rts = ts;
                if (copy_to_user(tsp, &rts, sizeof(rts))) {
Index: linux-cg/include/linux/poll.h
===================================================================
--- linux-cg.orig/include/linux/poll.h
+++ linux-cg/include/linux/poll.h
@@ -112,7 +112,7 @@ void zero_fd_set(unsigned long nr, unsig
 
 #define MAX_INT64_SECONDS (((s64)(~((u64)0)>>1)/HZ)-1)
 
-extern int do_select(int n, fd_set_bits *fds, s64 *timeout);
+extern int do_select(int n, fd_set_bits *fds, ktime_t *timeout);
 extern int do_sys_poll(struct pollfd __user * ufds, unsigned int nfds,
                       s64 *timeout);
 

--

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