fuse: fix race in llseek

[safe/jmp/linux-2.6] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 09ca69b..e2f7f5a 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -1657,42 +1657,6 @@ void aggregate_group_weight(struct task_group *tg, struct sched_domain *sd)
 }
 
 /*
- * Redistribute tg->shares amongst all tg->cfs_rq[]s.
- */
-static void __aggregate_redistribute_shares(struct task_group *tg)
-{
-       int i, max_cpu = smp_processor_id();
-       unsigned long rq_weight = 0;
-       unsigned long shares, max_shares = 0, shares_rem = tg->shares;
-
-       for_each_possible_cpu(i)
-               rq_weight += tg->cfs_rq[i]->load.weight;
-
-       for_each_possible_cpu(i) {
-               /*
-                * divide shares proportional to the rq_weights.
-                */
-               shares = tg->shares * tg->cfs_rq[i]->load.weight;
-               shares /= rq_weight + 1;
-
-               tg->cfs_rq[i]->shares = shares;
-
-               if (shares > max_shares) {
-                       max_shares = shares;
-                       max_cpu = i;
-               }
-               shares_rem -= shares;
-       }
-
-       /*
-        * Ensure it all adds up to tg->shares; we can loose a few
-        * due to rounding down when computing the per-cpu shares.
-        */
-       if (shares_rem)
-               tg->cfs_rq[max_cpu]->shares += shares_rem;
-}
-
-/*
  * Compute the weight of this group on the given cpus.
  */
 static
@@ -1701,18 +1665,11 @@ void aggregate_group_shares(struct task_group *tg, struct sched_domain *sd)
        unsigned long shares = 0;
        int i;
 
-again:
        for_each_cpu_mask(i, sd->span)
                shares += tg->cfs_rq[i]->shares;
 
-       /*
-        * When the span doesn't have any shares assigned, but does have
-        * tasks to run do a machine wide rebalance (should be rare).
-        */
-       if (unlikely(!shares && aggregate(tg, sd)->rq_weight)) {
-               __aggregate_redistribute_shares(tg);
-               goto again;
-       }
+       if ((!shares && aggregate(tg, sd)->rq_weight) || shares > tg->shares)
+               shares = tg->shares;
 
        aggregate(tg, sd)->shares = shares;
 }
@@ -7991,11 +7948,6 @@ void __init sched_init_smp(void)
 #else
 void __init sched_init_smp(void)
 {
-#if defined(CONFIG_NUMA)
-       sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
-                                                               GFP_KERNEL);
-       BUG_ON(sched_group_nodes_bycpu == NULL);
-#endif
        sched_init_granularity();
 }
 #endif /* CONFIG_SMP */
@@ -9105,13 +9057,13 @@ cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
 }
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
-static int cpu_shares_write_uint(struct cgroup *cgrp, struct cftype *cftype,
+static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype,
                                u64 shareval)
 {
        return sched_group_set_shares(cgroup_tg(cgrp), shareval);
 }
 
-static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft)
+static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
 {
        struct task_group *tg = cgroup_tg(cgrp);
 
@@ -9121,48 +9073,14 @@ static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft)
 
 #ifdef CONFIG_RT_GROUP_SCHED
 static ssize_t cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
-                               struct file *file,
-                               const char __user *userbuf,
-                               size_t nbytes, loff_t *unused_ppos)
+                               s64 val)
 {
-       char buffer[64];
-       int retval = 0;
-       s64 val;
-       char *end;
-
-       if (!nbytes)
-               return -EINVAL;
-       if (nbytes >= sizeof(buffer))
-               return -E2BIG;
-       if (copy_from_user(buffer, userbuf, nbytes))
-               return -EFAULT;
-
-       buffer[nbytes] = 0;     /* nul-terminate */
-
-       /* strip newline if necessary */
-       if (nbytes && (buffer[nbytes-1] == '\n'))
-               buffer[nbytes-1] = 0;
-       val = simple_strtoll(buffer, &end, 0);
-       if (*end)
-               return -EINVAL;
-
-       /* Pass to subsystem */
-       retval = sched_group_set_rt_runtime(cgroup_tg(cgrp), val);
-       if (!retval)
-               retval = nbytes;
-       return retval;
+       return sched_group_set_rt_runtime(cgroup_tg(cgrp), val);
 }
 
-static ssize_t cpu_rt_runtime_read(struct cgroup *cgrp, struct cftype *cft,
-                                  struct file *file,
-                                  char __user *buf, size_t nbytes,
-                                  loff_t *ppos)
+static s64 cpu_rt_runtime_read(struct cgroup *cgrp, struct cftype *cft)
 {
-       char tmp[64];
-       long val = sched_group_rt_runtime(cgroup_tg(cgrp));
-       int len = sprintf(tmp, "%ld\n", val);
-
-       return simple_read_from_buffer(buf, nbytes, ppos, tmp, len);
+       return sched_group_rt_runtime(cgroup_tg(cgrp));
 }
 
 static int cpu_rt_period_write_uint(struct cgroup *cgrp, struct cftype *cftype,
@@ -9181,20 +9099,20 @@ static struct cftype cpu_files[] = {
 #ifdef CONFIG_FAIR_GROUP_SCHED
        {
                .name = "shares",
-               .read_uint = cpu_shares_read_uint,
-               .write_uint = cpu_shares_write_uint,
+               .read_u64 = cpu_shares_read_u64,
+               .write_u64 = cpu_shares_write_u64,
        },
 #endif
 #ifdef CONFIG_RT_GROUP_SCHED
        {
                .name = "rt_runtime_us",
-               .read = cpu_rt_runtime_read,
-               .write = cpu_rt_runtime_write,
+               .read_s64 = cpu_rt_runtime_read,
+               .write_s64 = cpu_rt_runtime_write,
        },
        {
                .name = "rt_period_us",
-               .read_uint = cpu_rt_period_read_uint,
-               .write_uint = cpu_rt_period_write_uint,
+               .read_u64 = cpu_rt_period_read_uint,
+               .write_u64 = cpu_rt_period_write_uint,
        },
 #endif
 };
@@ -9325,8 +9243,8 @@ out:
 static struct cftype files[] = {
        {
                .name = "usage",
-               .read_uint = cpuusage_read,
-               .write_uint = cpuusage_write,
+               .read_u64 = cpuusage_read,
+               .write_u64 = cpuusage_write,
        },
 };