Fix cpuset sched_relax_domain_level control file

Due to a merge conflict, the sched_relax_domain_level control file was marked
as being handled by cpuset_read/write_u64, but the code to handle it was
actually in cpuset_common_file_read/write.

Since the value being written/read is in fact a signed integer, it should be
treated as such; this patch adds cpuset_read/write_s64 functions, and uses
them to handle the sched_relax_domain_level file.

With this patch, the sched_relax_domain_level can be read and written, and the
correct contents seen/updated.

Signed-off-by: Paul Menage <menage@google.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 8da627d..86ea9e3 100644 (file)
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1031,11 +1031,9 @@ int current_cpuset_is_being_rebound(void)
        return task_cs(current) == cpuset_being_rebound;
 }
 
-static int update_relax_domain_level(struct cpuset *cs, char *buf)
+static int update_relax_domain_level(struct cpuset *cs, s64 val)
 {
-       int val = simple_strtol(buf, NULL, 10);
-
-       if (val < 0)
+       if ((int)val < 0)
                val = -1;
 
        if (val != cs->relax_domain_level) {
@@ -1280,9 +1278,6 @@ static ssize_t cpuset_common_file_write(struct cgroup *cont,
        case FILE_MEMLIST:
                retval = update_nodemask(cs, buffer);
                break;
-       case FILE_SCHED_RELAX_DOMAIN_LEVEL:
-               retval = update_relax_domain_level(cs, buffer);
-               break;
        default:
                retval = -EINVAL;
                goto out2;
@@ -1348,6 +1343,30 @@ static int cpuset_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val)
        return retval;
 }
 
+static int cpuset_write_s64(struct cgroup *cgrp, struct cftype *cft, s64 val)
+{
+       int retval = 0;
+       struct cpuset *cs = cgroup_cs(cgrp);
+       cpuset_filetype_t type = cft->private;
+
+       cgroup_lock();
+
+       if (cgroup_is_removed(cgrp)) {
+               cgroup_unlock();
+               return -ENODEV;
+       }
+       switch (type) {
+       case FILE_SCHED_RELAX_DOMAIN_LEVEL:
+               retval = update_relax_domain_level(cs, val);
+               break;
+       default:
+               retval = -EINVAL;
+               break;
+       }
+       cgroup_unlock();
+       return retval;
+}
+
 /*
  * These ascii lists should be read in a single call, by using a user
  * buffer large enough to hold the entire map.  If read in smaller
@@ -1406,9 +1425,6 @@ static ssize_t cpuset_common_file_read(struct cgroup *cont,
        case FILE_MEMLIST:
                s += cpuset_sprintf_memlist(s, cs);
                break;
-       case FILE_SCHED_RELAX_DOMAIN_LEVEL:
-               s += sprintf(s, "%d", cs->relax_domain_level);
-               break;
        default:
                retval = -EINVAL;
                goto out;
@@ -1449,6 +1465,18 @@ static u64 cpuset_read_u64(struct cgroup *cont, struct cftype *cft)
        }
 }
 
+static s64 cpuset_read_s64(struct cgroup *cont, struct cftype *cft)
+{
+       struct cpuset *cs = cgroup_cs(cont);
+       cpuset_filetype_t type = cft->private;
+       switch (type) {
+       case FILE_SCHED_RELAX_DOMAIN_LEVEL:
+               return cs->relax_domain_level;
+       default:
+               BUG();
+       }
+}
+
 
 /*
  * for the common functions, 'private' gives the type of file
@@ -1499,8 +1527,8 @@ static struct cftype files[] = {
 
        {
                .name = "sched_relax_domain_level",
-               .read_u64 = cpuset_read_u64,
-               .write_u64 = cpuset_write_u64,
+               .read_s64 = cpuset_read_s64,
+               .write_s64 = cpuset_write_s64,
                .private = FILE_SCHED_RELAX_DOMAIN_LEVEL,
        },