| Message ID | 4C581C26.5080007@austin.ibm.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Tue, 03 Aug 2010 08:39:50 -0500 Nathan Fontenot <nfont@austin.ibm.com> wrote: > Add a new mutex for use in adding and removing of memory blocks. This > is needed to avoid any race conditions in which the same memory block could > be added and removed at the same time. > > Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> But a nitpick (see below) > --- > drivers/base/memory.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > Index: linux-2.6/drivers/base/memory.c > =================================================================== > --- linux-2.6.orig/drivers/base/memory.c 2010-08-02 13:35:00.000000000 -0500 > +++ linux-2.6/drivers/base/memory.c 2010-08-02 13:45:34.000000000 -0500 > @@ -27,6 +27,8 @@ > #include <asm/atomic.h> > #include <asm/uaccess.h> > > +static struct mutex mem_sysfs_mutex; > + For static symbol of mutex, we usually do static DEFINE_MUTEX(mem_sysfs_mutex); Then, extra calls of mutex_init() is not required.
On 08/04/2010 11:53 PM, KAMEZAWA Hiroyuki wrote: > On Tue, 03 Aug 2010 08:39:50 -0500 > Nathan Fontenot <nfont@austin.ibm.com> wrote: > >> Add a new mutex for use in adding and removing of memory blocks. This >> is needed to avoid any race conditions in which the same memory block could >> be added and removed at the same time. >> >> Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> > > Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> > > But a nitpick (see below) > >> --- >> drivers/base/memory.c | 9 +++++++++ >> 1 file changed, 9 insertions(+) >> >> Index: linux-2.6/drivers/base/memory.c >> =================================================================== >> --- linux-2.6.orig/drivers/base/memory.c 2010-08-02 13:35:00.000000000 -0500 >> +++ linux-2.6/drivers/base/memory.c 2010-08-02 13:45:34.000000000 -0500 >> @@ -27,6 +27,8 @@ >> #include <asm/atomic.h> >> #include <asm/uaccess.h> >> >> +static struct mutex mem_sysfs_mutex; >> + > > For static symbol of mutex, we usually do > static DEFINE_MUTEX(mem_sysfs_mutex); > > Then, extra calls of mutex_init() is not required. > ok, fixed in the next version of the patches. -Nathan
Index: linux-2.6/drivers/base/memory.c =================================================================== --- linux-2.6.orig/drivers/base/memory.c 2010-08-02 13:35:00.000000000 -0500 +++ linux-2.6/drivers/base/memory.c 2010-08-02 13:45:34.000000000 -0500 @@ -27,6 +27,8 @@ #include <asm/atomic.h> #include <asm/uaccess.h> +static struct mutex mem_sysfs_mutex; + #define MEMORY_CLASS_NAME "memory" static struct sysdev_class memory_sysdev_class = { @@ -485,6 +487,8 @@ static int add_memory_block(int nid, str if (!mem) return -ENOMEM; + mutex_lock(&mem_sysfs_mutex); + mem->start_phys_index = __section_nr(section); mem->state = state; atomic_inc(&mem->section_count); @@ -508,6 +512,7 @@ static int add_memory_block(int nid, str ret = register_mem_sect_under_node(mem, nid); } + mutex_unlock(&mem_sysfs_mutex); return ret; } @@ -516,6 +521,7 @@ int remove_memory_block(unsigned long no { struct memory_block *mem; + mutex_lock(&mem_sysfs_mutex); mem = find_memory_block(section); if (atomic_dec_and_test(&mem->section_count)) { @@ -528,6 +534,7 @@ int remove_memory_block(unsigned long no unregister_memory(mem, section); } + mutex_unlock(&mem_sysfs_mutex); return 0; } @@ -562,6 +569,8 @@ int __init memory_dev_init(void) if (ret) goto out; + mutex_init(&mem_sysfs_mutex); + /* * Create entries for memory sections that were found * during boot and have been initialized
Add a new mutex for use in adding and removing of memory blocks. This is needed to avoid any race conditions in which the same memory block could be added and removed at the same time. Signed-off-by: Nathan Fontenot <nfont@austin.ibm.com> --- drivers/base/memory.c | 9 +++++++++ 1 file changed, 9 insertions(+)