Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754873Ab2JETmO (ORCPT ); Fri, 5 Oct 2012 15:42:14 -0400 Received: from mail-ob0-f174.google.com ([209.85.214.174]:54966 "EHLO mail-ob0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750936Ab2JETmJ (ORCPT ); Fri, 5 Oct 2012 15:42:09 -0400 MIME-Version: 1.0 In-Reply-To: <506E4571.4090608@jp.fujitsu.com> References: <506E43E0.70507@jp.fujitsu.com> <506E4571.4090608@jp.fujitsu.com> From: KOSAKI Motohiro Date: Fri, 5 Oct 2012 15:36:52 -0400 X-Google-Sender-Auth: hB3ePeGUCFEAA9yoXs1wLJwMXUE Message-ID: Subject: Re: [PATCH 2/10] memory-hotplug : remove /sys/firmware/memmap/X sysfs To: Yasuaki Ishimatsu Cc: x86@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-ia64@vger.kernel.org, cmetcalf@tilera.com, sparclinux@vger.kernel.org, rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org, wency@cn.fujitsu.com Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8750 Lines: 268 On Thu, Oct 4, 2012 at 10:26 PM, Yasuaki Ishimatsu wrote: > When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type} > sysfs files are created. But there is no code to remove these files. The patch > implements the function to remove them. > > Note : The code does not free firmware_map_entry since there is no way to free > memory which is allocated by bootmem. You have to explain why this is ok. I guess the unfreed firmware_map_entry is reused at next online memory and don't make memory leak, right? > > CC: David Rientjes > CC: Jiang Liu > CC: Len Brown > CC: Christoph Lameter > Cc: Minchan Kim > CC: Andrew Morton > CC: KOSAKI Motohiro > Signed-off-by: Wen Congyang > Signed-off-by: Yasuaki Ishimatsu > > --- > drivers/firmware/memmap.c | 98 ++++++++++++++++++++++++++++++++++++++++++- > include/linux/firmware-map.h | 6 ++ > mm/memory_hotplug.c | 7 ++- > 3 files changed, 108 insertions(+), 3 deletions(-) > > Index: linux-3.6/drivers/firmware/memmap.c > =================================================================== > --- linux-3.6.orig/drivers/firmware/memmap.c 2012-10-04 18:27:05.195500420 +0900 > +++ linux-3.6/drivers/firmware/memmap.c 2012-10-04 18:27:18.901514330 +0900 > @@ -21,6 +21,7 @@ > #include > #include > #include > +#include > > /* > * Data types ------------------------------------------------------------------ > @@ -41,6 +42,7 @@ struct firmware_map_entry { > const char *type; /* type of the memory range */ > struct list_head list; /* entry for the linked list */ > struct kobject kobj; /* kobject for each entry */ > + unsigned int bootmem:1; /* allocated from bootmem */ Use bool. > }; > > /* > @@ -79,7 +81,26 @@ static const struct sysfs_ops memmap_att > .show = memmap_attr_show, > }; > > + > +static inline struct firmware_map_entry * > +to_memmap_entry(struct kobject *kobj) > +{ > + return container_of(kobj, struct firmware_map_entry, kobj); > +} > + > +static void release_firmware_map_entry(struct kobject *kobj) > +{ > + struct firmware_map_entry *entry = to_memmap_entry(kobj); > + > + if (entry->bootmem) > + /* There is no way to free memory allocated from bootmem */ > + return; > + > + kfree(entry); > +} > + > static struct kobj_type memmap_ktype = { > + .release = release_firmware_map_entry, > .sysfs_ops = &memmap_attr_ops, > .default_attrs = def_attrs, > }; > @@ -94,6 +115,7 @@ static struct kobj_type memmap_ktype = { > * in firmware initialisation code in one single thread of execution. > */ > static LIST_HEAD(map_entries); > +static DEFINE_SPINLOCK(map_entries_lock); > > /** > * firmware_map_add_entry() - Does the real work to add a firmware memmap entry. > @@ -118,11 +140,25 @@ static int firmware_map_add_entry(u64 st > INIT_LIST_HEAD(&entry->list); > kobject_init(&entry->kobj, &memmap_ktype); > > + spin_lock(&map_entries_lock); > list_add_tail(&entry->list, &map_entries); > + spin_unlock(&map_entries_lock); > > return 0; > } > > +/** > + * firmware_map_remove_entry() - Does the real work to remove a firmware > + * memmap entry. > + * @entry: removed entry. > + **/ > +static inline void firmware_map_remove_entry(struct firmware_map_entry *entry) Don't use inline in *.c file. gcc is wise than you. > +{ > + spin_lock(&map_entries_lock); > + list_del(&entry->list); > + spin_unlock(&map_entries_lock); > +} > + > /* > * Add memmap entry on sysfs > */ > @@ -144,6 +180,35 @@ static int add_sysfs_fw_map_entry(struct > return 0; > } > > +/* > + * Remove memmap entry on sysfs > + */ > +static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry) > +{ > + kobject_put(&entry->kobj); > +} > + > +/* > + * Search memmap entry > + */ > + > +static struct firmware_map_entry * __meminit > +firmware_map_find_entry(u64 start, u64 end, const char *type) > +{ > + struct firmware_map_entry *entry; > + > + spin_lock(&map_entries_lock); > + list_for_each_entry(entry, &map_entries, list) > + if ((entry->start == start) && (entry->end == end) && > + (!strcmp(entry->type, type))) { > + spin_unlock(&map_entries_lock); > + return entry; > + } > + > + spin_unlock(&map_entries_lock); > + return NULL; > +} > + > /** > * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do > * memory hotplug. > @@ -193,9 +258,36 @@ int __init firmware_map_add_early(u64 st > if (WARN_ON(!entry)) > return -ENOMEM; > > + entry->bootmem = 1; > return firmware_map_add_entry(start, end, type, entry); > } > > +/** > + * firmware_map_remove() - remove a firmware mapping entry > + * @start: Start of the memory range. > + * @end: End of the memory range. > + * @type: Type of the memory range. > + * > + * removes a firmware mapping entry. > + * > + * Returns 0 on success, or -EINVAL if no entry. > + **/ > +int __meminit firmware_map_remove(u64 start, u64 end, const char *type) Remove type argument if this is always passed "System RAM". > +{ > + struct firmware_map_entry *entry; > + > + entry = firmware_map_find_entry(start, end - 1, type); > + if (!entry) > + return -EINVAL; > + > + firmware_map_remove_entry(entry); > + > + /* remove the memmap entry */ > + remove_sysfs_fw_map_entry(entry); > + > + return 0; > +} > + > /* > * Sysfs functions ------------------------------------------------------------- > */ > @@ -217,8 +309,10 @@ static ssize_t type_show(struct firmware > return snprintf(buf, PAGE_SIZE, "%s\n", entry->type); > } > > -#define to_memmap_attr(_attr) container_of(_attr, struct memmap_attribute, attr) > -#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) > +static inline struct memmap_attribute *to_memmap_attr(struct attribute *attr) > +{ > + return container_of(attr, struct memmap_attribute, attr); > +} > > static ssize_t memmap_attr_show(struct kobject *kobj, > struct attribute *attr, char *buf) > Index: linux-3.6/include/linux/firmware-map.h > =================================================================== > --- linux-3.6.orig/include/linux/firmware-map.h 2012-10-04 18:27:05.197500422 +0900 > +++ linux-3.6/include/linux/firmware-map.h 2012-10-04 18:27:18.904514333 +0900 > @@ -25,6 +25,7 @@ > > int firmware_map_add_early(u64 start, u64 end, const char *type); > int firmware_map_add_hotplug(u64 start, u64 end, const char *type); > +int firmware_map_remove(u64 start, u64 end, const char *type); > > #else /* CONFIG_FIRMWARE_MEMMAP */ > > @@ -38,6 +39,11 @@ static inline int firmware_map_add_hotpl > return 0; > } > > +static inline int firmware_map_remove(u64 start, u64 end, const char *type) > +{ > + return 0; > +} > + > #endif /* CONFIG_FIRMWARE_MEMMAP */ > > #endif /* _LINUX_FIRMWARE_MAP_H */ > Index: linux-3.6/mm/memory_hotplug.c > =================================================================== > --- linux-3.6.orig/mm/memory_hotplug.c 2012-10-04 18:27:03.000000000 +0900 > +++ linux-3.6/mm/memory_hotplug.c 2012-10-04 18:28:42.851599524 +0900 > @@ -1043,7 +1043,7 @@ int offline_memory(u64 start, u64 size) > return 0; > } > > -int remove_memory(int nid, u64 start, u64 size) > +int __ref remove_memory(int nid, u64 start, u64 size) > { > int ret = 0; > lock_memory_hotplug(); > @@ -1056,8 +1056,13 @@ int remove_memory(int nid, u64 start, u6 > "because the memmory range is online\n", > start, start + size); > ret = -EAGAIN; > + goto out; > } > > + /* remove memmap entry */ > + firmware_map_remove(start, start + size, "System RAM"); > + > +out: > unlock_memory_hotplug(); > return ret; > } Other than that, looks ok to me. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/