diff options
| author | Dave Hansen <haveblue@us.ibm.com> | 2005-10-29 18:16:52 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-10-29 21:40:44 -0700 |
| commit | 208d54e5513c0c02d85af0990901354c74364d5c (patch) | |
| tree | 83922f1d4a83f19bffcbff299044f421bd7e9c73 /arch/ia64/mm/discontig.c | |
| parent | c6a57e19e464db118dc4ab9cfe9e9748c6d630a0 (diff) | |
| download | linux-208d54e5513c0c02d85af0990901354c74364d5c.tar.gz | |
[PATCH] memory hotplug locking: node_size_lock
pgdat->node_size_lock is basically only neeeded in one place in the normal
code: show_mem(), which is the arch-specific sysrq-m printing function.
Strictly speaking, the architectures not doing memory hotplug do no need this
locking in show_mem(). However, they are all included for completeness. This
should also make any future consolidation of all of the implementations a
little more straightforward.
This lock is also held in the sparsemem code during a memory removal, as
sections are invalidated. This is the place there pfn_valid() is made false
for a memory area that's being removed. The lock is only required when doing
pfn_valid() operations on memory which the user does not already have a
reference on the page, such as in show_mem().
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/ia64/mm/discontig.c')
| -rw-r--r-- | arch/ia64/mm/discontig.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index a3788fb84809a..a88cdb7232f8e 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -555,9 +555,13 @@ void show_mem(void) show_free_areas(); printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); for_each_pgdat(pgdat) { - unsigned long present = pgdat->node_present_pages; + unsigned long present; + unsigned long flags; int shared = 0, cached = 0, reserved = 0; + printk("Node ID: %d\n", pgdat->node_id); + pgdat_resize_lock(pgdat, &flags); + present = pgdat->node_present_pages; for(i = 0; i < pgdat->node_spanned_pages; i++) { struct page *page; if (pfn_valid(pgdat->node_start_pfn + i)) @@ -571,6 +575,7 @@ void show_mem(void) else if (page_count(page)) shared += page_count(page)-1; } + pgdat_resize_unlock(pgdat, &flags); total_present += present; total_reserved += reserved; total_cached += cached; |