signals: check_kill_permission: remove tasklist_lock
[safe/jmp/linux-2.6] / kernel / cpuset.c
index b557127..8da627d 100644 (file)
@@ -127,6 +127,7 @@ struct cpuset_hotplug_scanner {
 typedef enum {
        CS_CPU_EXCLUSIVE,
        CS_MEM_EXCLUSIVE,
+       CS_MEM_HARDWALL,
        CS_MEMORY_MIGRATE,
        CS_SCHED_LOAD_BALANCE,
        CS_SPREAD_PAGE,
@@ -144,6 +145,11 @@ static inline int is_mem_exclusive(const struct cpuset *cs)
        return test_bit(CS_MEM_EXCLUSIVE, &cs->flags);
 }
 
+static inline int is_mem_hardwall(const struct cpuset *cs)
+{
+       return test_bit(CS_MEM_HARDWALL, &cs->flags);
+}
+
 static inline int is_sched_load_balance(const struct cpuset *cs)
 {
        return test_bit(CS_SCHED_LOAD_BALANCE, &cs->flags);
@@ -1042,12 +1048,9 @@ static int update_relax_domain_level(struct cpuset *cs, char *buf)
 
 /*
  * update_flag - read a 0 or a 1 in a file and update associated flag
- * bit:        the bit to update (CS_CPU_EXCLUSIVE, CS_MEM_EXCLUSIVE,
- *                             CS_SCHED_LOAD_BALANCE,
- *                             CS_NOTIFY_ON_RELEASE, CS_MEMORY_MIGRATE,
- *                             CS_SPREAD_PAGE, CS_SPREAD_SLAB)
- * cs: the cpuset to update
- * buf:        the buffer where we read the 0 or 1
+ * bit:                the bit to update (see cpuset_flagbits_t)
+ * cs:         the cpuset to update
+ * turning_on:         whether the flag is being set or cleared
  *
  * Call with cgroup_mutex held.
  */
@@ -1228,6 +1231,7 @@ typedef enum {
        FILE_MEMLIST,
        FILE_CPU_EXCLUSIVE,
        FILE_MEM_EXCLUSIVE,
+       FILE_MEM_HARDWALL,
        FILE_SCHED_LOAD_BALANCE,
        FILE_SCHED_RELAX_DOMAIN_LEVEL,
        FILE_MEMORY_PRESSURE_ENABLED,
@@ -1313,6 +1317,9 @@ static int cpuset_write_u64(struct cgroup *cgrp, struct cftype *cft, u64 val)
        case FILE_MEM_EXCLUSIVE:
                retval = update_flag(CS_MEM_EXCLUSIVE, cs, val);
                break;
+       case FILE_MEM_HARDWALL:
+               retval = update_flag(CS_MEM_HARDWALL, cs, val);
+               break;
        case FILE_SCHED_LOAD_BALANCE:
                retval = update_flag(CS_SCHED_LOAD_BALANCE, cs, val);
                break;
@@ -1423,6 +1430,8 @@ static u64 cpuset_read_u64(struct cgroup *cont, struct cftype *cft)
                return is_cpu_exclusive(cs);
        case FILE_MEM_EXCLUSIVE:
                return is_mem_exclusive(cs);
+       case FILE_MEM_HARDWALL:
+               return is_mem_hardwall(cs);
        case FILE_SCHED_LOAD_BALANCE:
                return is_sched_load_balance(cs);
        case FILE_MEMORY_MIGRATE:
@@ -1445,53 +1454,83 @@ static u64 cpuset_read_u64(struct cgroup *cont, struct cftype *cft)
  * for the common functions, 'private' gives the type of file
  */
 
-static struct cftype cft_cpus = {
-       .name = "cpus",
-       .read = cpuset_common_file_read,
-       .write = cpuset_common_file_write,
-       .private = FILE_CPULIST,
-};
-
-static struct cftype cft_mems = {
-       .name = "mems",
-       .read = cpuset_common_file_read,
-       .write = cpuset_common_file_write,
-       .private = FILE_MEMLIST,
-};
-
-static struct cftype cft_cpu_exclusive = {
-       .name = "cpu_exclusive",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_CPU_EXCLUSIVE,
-};
-
-static struct cftype cft_mem_exclusive = {
-       .name = "mem_exclusive",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_MEM_EXCLUSIVE,
-};
-
-static struct cftype cft_sched_load_balance = {
-       .name = "sched_load_balance",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_SCHED_LOAD_BALANCE,
-};
-
-static struct cftype cft_sched_relax_domain_level = {
-       .name = "sched_relax_domain_level",
-       .read = cpuset_common_file_read,
-       .write = cpuset_common_file_write,
-       .private = FILE_SCHED_RELAX_DOMAIN_LEVEL,
-};
-
-static struct cftype cft_memory_migrate = {
-       .name = "memory_migrate",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_MEMORY_MIGRATE,
+static struct cftype files[] = {
+       {
+               .name = "cpus",
+               .read = cpuset_common_file_read,
+               .write = cpuset_common_file_write,
+               .private = FILE_CPULIST,
+       },
+
+       {
+               .name = "mems",
+               .read = cpuset_common_file_read,
+               .write = cpuset_common_file_write,
+               .private = FILE_MEMLIST,
+       },
+
+       {
+               .name = "cpu_exclusive",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_CPU_EXCLUSIVE,
+       },
+
+       {
+               .name = "mem_exclusive",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_MEM_EXCLUSIVE,
+       },
+
+       {
+               .name = "mem_hardwall",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_MEM_HARDWALL,
+       },
+
+       {
+               .name = "sched_load_balance",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_SCHED_LOAD_BALANCE,
+       },
+
+       {
+               .name = "sched_relax_domain_level",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_SCHED_RELAX_DOMAIN_LEVEL,
+       },
+
+       {
+               .name = "memory_migrate",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_MEMORY_MIGRATE,
+       },
+
+       {
+               .name = "memory_pressure",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_MEMORY_PRESSURE,
+       },
+
+       {
+               .name = "memory_spread_page",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_SPREAD_PAGE,
+       },
+
+       {
+               .name = "memory_spread_slab",
+               .read_u64 = cpuset_read_u64,
+               .write_u64 = cpuset_write_u64,
+               .private = FILE_SPREAD_SLAB,
+       },
 };
 
 static struct cftype cft_memory_pressure_enabled = {
@@ -1501,57 +1540,18 @@ static struct cftype cft_memory_pressure_enabled = {
        .private = FILE_MEMORY_PRESSURE_ENABLED,
 };
 
-static struct cftype cft_memory_pressure = {
-       .name = "memory_pressure",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_MEMORY_PRESSURE,
-};
-
-static struct cftype cft_spread_page = {
-       .name = "memory_spread_page",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_SPREAD_PAGE,
-};
-
-static struct cftype cft_spread_slab = {
-       .name = "memory_spread_slab",
-       .read_u64 = cpuset_read_u64,
-       .write_u64 = cpuset_write_u64,
-       .private = FILE_SPREAD_SLAB,
-};
-
 static int cpuset_populate(struct cgroup_subsys *ss, struct cgroup *cont)
 {
        int err;
 
-       if ((err = cgroup_add_file(cont, ss, &cft_cpus)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_mems)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_cpu_exclusive)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_mem_exclusive)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_memory_migrate)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_sched_load_balance)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss,
-                                       &cft_sched_relax_domain_level)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_memory_pressure)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_spread_page)) < 0)
-               return err;
-       if ((err = cgroup_add_file(cont, ss, &cft_spread_slab)) < 0)
+       err = cgroup_add_files(cont, ss, files, ARRAY_SIZE(files));
+       if (err)
                return err;
        /* memory_pressure_enabled is in root cpuset only */
-       if (err == 0 && !cont->parent)
+       if (!cont->parent)
                err = cgroup_add_file(cont, ss,
-                                        &cft_memory_pressure_enabled);
-       return 0;
+                                     &cft_memory_pressure_enabled);
+       return err;
 }
 
 /*
@@ -1979,14 +1979,14 @@ int cpuset_nodemask_valid_mems_allowed(nodemask_t *nodemask)
 }
 
 /*
- * nearest_exclusive_ancestor() - Returns the nearest mem_exclusive
- * ancestor to the specified cpuset.  Call holding callback_mutex.
- * If no ancestor is mem_exclusive (an unusual configuration), then
- * returns the root cpuset.
+ * nearest_hardwall_ancestor() - Returns the nearest mem_exclusive or
+ * mem_hardwall ancestor to the specified cpuset.  Call holding
+ * callback_mutex.  If no ancestor is mem_exclusive or mem_hardwall
+ * (an unusual configuration), then returns the root cpuset.
  */
-static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
+static const struct cpuset *nearest_hardwall_ancestor(const struct cpuset *cs)
 {
-       while (!is_mem_exclusive(cs) && cs->parent)
+       while (!(is_mem_exclusive(cs) || is_mem_hardwall(cs)) && cs->parent)
                cs = cs->parent;
        return cs;
 }
@@ -2000,7 +2000,7 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
  * __GFP_THISNODE is set, yes, we can always allocate.  If zone
  * z's node is in our tasks mems_allowed, yes.  If it's not a
  * __GFP_HARDWALL request and this zone's nodes is in the nearest
- * mem_exclusive cpuset ancestor to this tasks cpuset, yes.
+ * hardwalled cpuset ancestor to this tasks cpuset, yes.
  * If the task has been OOM killed and has access to memory reserves
  * as specified by the TIF_MEMDIE flag, yes.
  * Otherwise, no.
@@ -2023,7 +2023,7 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
  * and do not allow allocations outside the current tasks cpuset
  * unless the task has been OOM killed as is marked TIF_MEMDIE.
  * GFP_KERNEL allocations are not so marked, so can escape to the
- * nearest enclosing mem_exclusive ancestor cpuset.
+ * nearest enclosing hardwalled ancestor cpuset.
  *
  * Scanning up parent cpusets requires callback_mutex.  The
  * __alloc_pages() routine only calls here with __GFP_HARDWALL bit
@@ -2046,7 +2046,7 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
  *     in_interrupt - any node ok (current task context irrelevant)
  *     GFP_ATOMIC   - any node ok
  *     TIF_MEMDIE   - any node ok
- *     GFP_KERNEL   - any node in enclosing mem_exclusive cpuset ok
+ *     GFP_KERNEL   - any node in enclosing hardwalled cpuset ok
  *     GFP_USER     - only nodes in current tasks mems allowed ok.
  *
  * Rule:
@@ -2083,7 +2083,7 @@ int __cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
        mutex_lock(&callback_mutex);
 
        task_lock(current);
-       cs = nearest_exclusive_ancestor(task_cs(current));
+       cs = nearest_hardwall_ancestor(task_cs(current));
        task_unlock(current);
 
        allowed = node_isset(node, cs->mems_allowed);