Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

cpu hotplug: intel_cacheinfo: fix cpu hotplug error handling

Browse source 
- Fix resource leakage in error case within detect_cache_attributes()

- Don't register hotcpu notifier when cache_add_dev() returns error

- Introduce cache_dev_map cpumask to track whether cache interface for
  CPU is successfully added by cache_add_dev() or not.

  cache_add_dev() may fail with out of memory error. In order to
  avoid cache_remove_dev() with that uninitialized cache interface when
  CPU_DEAD event is delivered we need to have the cache_dev_map cpumask.

  (We cannot change cache_add_dev() from CPU_ONLINE event handler
  to CPU_UP_PREPARE event handler. Because cache_add_dev() needs
  to do cpuid and store the results with its CPU online.)

[nix.or.die@googlemail.com: fix a section mismatch warning]
Cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andi Kleen <ak@suse.de>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Gabriel Craciunescu <nix.or.die@googlemail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Akinobu Mita 2007-10-18 03:05:16 -07:00 committed by Linus Torvalds
parent d435d862ba
commit ef1d7151d2
1 changed files with 45 additions and 21 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

66
arch/x86/kernel/cpu/intel_cacheinfo.c
View file

@ -499,6 +499,11 @@ static void __cpuinit cache_remove_shared_cpu_map(unsigned int cpu, int index) {
static void free_cache_attributes(unsigned int cpu)
{
int i;
for (i = 0; i < num_cache_leaves; i++)
cache_remove_shared_cpu_map(cpu, i);
kfree(cpuid4_info[cpu]);
cpuid4_info[cpu] = NULL;
}
@ -506,8 +511,8 @@ static void free_cache_attributes(unsigned int cpu)
static int __cpuinit detect_cache_attributes(unsigned int cpu)
{
struct _cpuid4_info *this_leaf;
unsigned long j;
int retval;
unsigned long j;
int retval;
cpumask_t oldmask;
if (num_cache_leaves == 0)
@ -524,19 +529,26 @@ static int __cpuinit detect_cache_attributes(unsigned int cpu)
goto out;
/* Do cpuid and store the results */
retval = 0;
for (j = 0; j < num_cache_leaves; j++) {
this_leaf = CPUID4_INFO_IDX(cpu, j);
retval = cpuid4_cache_lookup(j, this_leaf);
if (unlikely(retval < 0))
if (unlikely(retval < 0)) {
int i;
for (i = 0; i < j; i++)
cache_remove_shared_cpu_map(cpu, i);
break;
}
cache_shared_cpu_map_setup(cpu, j);
}
set_cpus_allowed(current, oldmask);
out:
if (retval)
free_cache_attributes(cpu);
if (retval) {
kfree(cpuid4_info[cpu]);
cpuid4_info[cpu] = NULL;
}
return retval;
}
@ -669,7 +681,7 @@ static struct kobj_type ktype_percpu_entry = {
.sysfs_ops = &sysfs_ops,
};
static void cpuid4_cache_sysfs_exit(unsigned int cpu)
static void __cpuinit cpuid4_cache_sysfs_exit(unsigned int cpu)
{
kfree(cache_kobject[cpu]);
kfree(index_kobject[cpu]);
@ -680,13 +692,14 @@ static void cpuid4_cache_sysfs_exit(unsigned int cpu)
static int __cpuinit cpuid4_cache_sysfs_init(unsigned int cpu)
{
int err;
if (num_cache_leaves == 0)
return -ENOENT;
detect_cache_attributes(cpu);
if (cpuid4_info[cpu] == NULL)
return -ENOENT;
err = detect_cache_attributes(cpu);
if (err)
return err;
/* Allocate all required memory */
cache_kobject[cpu] = kzalloc(sizeof(struct kobject), GFP_KERNEL);
@ -705,13 +718,15 @@ static int __cpuinit cpuid4_cache_sysfs_init(unsigned int cpu)
return -ENOMEM;
}
static cpumask_t cache_dev_map = CPU_MASK_NONE;
/* Add/Remove cache interface for CPU device */
static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
{
unsigned int cpu = sys_dev->id;
unsigned long i, j;
struct _index_kobject *this_object;
int retval = 0;
int retval;
retval = cpuid4_cache_sysfs_init(cpu);
if (unlikely(retval < 0))
@ -721,6 +736,10 @@ static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
kobject_set_name(cache_kobject[cpu], "%s", "cache");
cache_kobject[cpu]->ktype = &ktype_percpu_entry;
retval = kobject_register(cache_kobject[cpu]);
if (retval < 0) {
cpuid4_cache_sysfs_exit(cpu);
return retval;
}
for (i = 0; i < num_cache_leaves; i++) {
this_object = INDEX_KOBJECT_PTR(cpu,i);
@ -740,6 +759,9 @@ static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
break;
}
}
if (!retval)
cpu_set(cpu, cache_dev_map);
return retval;
}
@ -750,13 +772,14 @@ static void __cpuinit cache_remove_dev(struct sys_device * sys_dev)
if (cpuid4_info[cpu] == NULL)
return;
for (i = 0; i < num_cache_leaves; i++) {
cache_remove_shared_cpu_map(cpu, i);
if (!cpu_isset(cpu, cache_dev_map))
return;
cpu_clear(cpu, cache_dev_map);
for (i = 0; i < num_cache_leaves; i++)
kobject_unregister(&(INDEX_KOBJECT_PTR(cpu,i)->kobj));
}
kobject_unregister(cache_kobject[cpu]);
cpuid4_cache_sysfs_exit(cpu);
return;
}
static int __cpuinit cacheinfo_cpu_callback(struct notifier_block *nfb,
@ -781,7 +804,7 @@ static int __cpuinit cacheinfo_cpu_callback(struct notifier_block *nfb,
static struct notifier_block __cpuinitdata cacheinfo_cpu_notifier =
{
.notifier_call = cacheinfo_cpu_callback,
.notifier_call = cacheinfo_cpu_callback,
};
static int __cpuinit cache_sysfs_init(void)
@ -791,14 +814,15 @@ static int __cpuinit cache_sysfs_init(void)
if (num_cache_leaves == 0)
return 0;
register_hotcpu_notifier(&cacheinfo_cpu_notifier);
for_each_online_cpu(i) {
struct sys_device *sys_dev = get_cpu_sysdev((unsigned int)i);
int err;
struct sys_device *sys_dev = get_cpu_sysdev(i);
cache_add_dev(sys_dev);
err = cache_add_dev(sys_dev);
if (err)
return err;
}
register_hotcpu_notifier(&cacheinfo_cpu_notifier);
return 0;
}