git pull on ia64 linux tree

Luck, Tony
2006-08-04T18:20:02Z

Hi Linus,

I missed one patch that I meant to include in the batch yesterday.

Please pull (again) from:

git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6.git release

This will update the file shown below.

Thanks!

-Tony

arch/ia64/kernel/uncached.c | 86 +++++++++++++++++++++++++++++---------------
1 files changed, 57 insertions(+), 29 deletions(-)

Dean Nelson:
[IA64] make uncached allocator more node aware

commit eca7994f60eb6550d9e9b36d3b641a5a0e18a7c1
Author: Dean Nelson <dcn@sgi.com>
Date: Wed Jun 28 13:50:09 2006 -0500

[IA64] make uncached allocator more node aware

The uncached allocator has a function, uncached_get_new_chunk(), that needs
to be serialized on a per node basis. It also has a global variable,
allocated_granules, which should be defined on a per node basis and protected
by that serialization. Additionally, all error returns from functions called
(like ia64_pal_mc_drain()) should be handled appropriately.

Signed-off-by: Dean Nelson <dcn@sgi.com>
Acked-by: Jes Sorenson <jes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

diff --git a/arch/ia64/kernel/uncached.c b/arch/ia64/kernel/uncached.c
index 5f03b9e..4c73a67 100644
--- a/arch/ia64/kernel/uncached.c
+++ b/arch/ia64/kernel/uncached.c
@@ -32,32 +32,38 @@ #include <asm/sn/arch.h>

extern void __init efi_memmap_walk_uc(efi_freemem_callback_t, void *);

-#define MAX_UNCACHED_GRANULES 5
-static int allocated_granules;
+struct uncached_pool {
+ struct gen_pool *pool;
+ struct mutex add_chunk_mutex; /* serialize adding a converted chunk */
+ int nchunks_added; /* #of converted chunks added to pool */
+ atomic_t status; /* smp called function's return status*/
+};
+
+#define MAX_CONVERTED_CHUNKS_PER_NODE 2

-struct gen_pool *uncached_pool[MAX_NUMNODES];
+struct uncached_pool uncached_pools[MAX_NUMNODES];

static void uncached_ipi_visibility(void *data)
{
int status;
+ struct uncached_pool *uc_pool = (struct uncached_pool *)data;

status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
if ((status != PAL_VISIBILITY_OK) &&
(status != PAL_VISIBILITY_OK_REMOTE_NEEDED))
- printk(KERN_DEBUG "pal_prefetch_visibility() returns %i on "
- "CPU %i\n", status, raw_smp_processor_id());
+ atomic_inc(&uc_pool->status);
}

static void uncached_ipi_mc_drain(void *data)
{
int status;
+ struct uncached_pool *uc_pool = (struct uncached_pool *)data;

status = ia64_pal_mc_drain();
- if (status)
- printk(KERN_WARNING "ia64_pal_mc_drain() failed with %i on "
- "CPU %i\n", status, raw_smp_processor_id());
+ if (status != PAL_STATUS_SUCCESS)
+ atomic_inc(&uc_pool->status);
}

@@ -70,21 +76,34 @@ static void uncached_ipi_mc_drain(void *
* This is accomplished by first allocating a granule of cached memory pages
* and then converting them to uncached memory pages.
*/
-static int uncached_add_chunk(struct gen_pool *pool, int nid)
+static int uncached_add_chunk(struct uncached_pool *uc_pool, int nid)
{
struct page *page;
- int status, i;
+ int status, i, nchunks_added = uc_pool->nchunks_added;
unsigned long c_addr, uc_addr;

- if (allocated_granules >= MAX_UNCACHED_GRANULES)
+ if (mutex_lock_interruptible(&uc_pool->add_chunk_mutex) != 0)
+ return -1; /* interrupted by a signal */
+
+ if (uc_pool->nchunks_added > nchunks_added) {
+ /* someone added a new chunk while we were waiting */
+ mutex_unlock(&uc_pool->add_chunk_mutex);
+ return 0;
+ }
+
+ if (uc_pool->nchunks_added >= MAX_CONVERTED_CHUNKS_PER_NODE) {
+ mutex_unlock(&uc_pool->add_chunk_mutex);
return -1;
+ }

/* attempt to allocate a granule's worth of cached memory pages */

page = alloc_pages_node(nid, GFP_KERNEL | __GFP_ZERO,
IA64_GRANULE_SHIFT-PAGE_SHIFT);
- if (!page)
+ if (!page) {
+ mutex_unlock(&uc_pool->add_chunk_mutex);
return -1;
+ }

/* convert the memory pages from cached to uncached */

@@ -102,11 +121,14 @@ static int uncached_add_chunk(struct gen
flush_tlb_kernel_range(uc_addr, uc_adddr + IA64_GRANULE_SIZE);

status = ia64_pal_prefetch_visibility(PAL_VISIBILITY_PHYSICAL);
- if (!status) {
- status = smp_call_function(uncached_ipi_visibility, NULL, 0, 1);
- if (status)
+ if (status = PAL_VISIBILITY_OK_REMOTE_NEEDED) {
+ atomic_set(&uc_pool->status, 0);
+ status = smp_call_function(uncached_ipi_visibility, uc_pool,
+ 0, 1);
+ if (status || atomic_read(&uc_pool->status))
goto failed;
- }
+ } else if (status != PAL_VISIBILITY_OK)
+ goto failed;

preempt_disable();

@@ -120,20 +142,24 @@ static int uncached_add_chunk(struct gen

preempt_enable();

- ia64_pal_mc_drain();
- status = smp_call_function(uncached_ipi_mc_drain, NULL, 0, 1);
- if (status)
+ status = ia64_pal_mc_drain();
+ if (status != PAL_STATUS_SUCCESS)
+ goto failed;
+ atomic_set(&uc_pool->status, 0);
+ status = smp_call_function(uncached_ipi_mc_drain, uc_pool, 0, 1);
+ if (status || atomic_read(&uc_pool->status))
goto failed;

/*
* The chunk of memory pages has been converted to uncached so now we
* can add it to the pool.
*/
- status = gen_pool_add(pool, uc_addr, IA64_GRANULE_SIZE, nid);
+ status = gen_pool_add(uc_pool->pool, uc_addr, IA64_GRANULE_SIZE, nid);
if (status)
goto failed;

- allocated_granules++;
+ uc_pool->nchunks_added++;
+ mutex_unlock(&uc_pool->add_chunk_mutex);
return 0;

/* failed to convert or add the chunk so give it back to the kernel */
@@ -142,6 +168,7 @@ failed:
ClearPageUncached(&page[i]);

free_pages(c_addr, IA64_GRANULE_SHIFT-PAGE_SHIFT);
+ mutex_unlock(&uc_pool->add_chunk_mutex);
return -1;
}

@@ -158,7 +185,7 @@ failed:
unsigned long uncached_alloc_page(int starting_nid)
{
unsigned long uc_addr;
- struct gen_pool *pool;
+ struct uncached_pool *uc_pool;
int nid;

if (unlikely(starting_nid >= MAX_NUMNODES))
@@ -171,14 +198,14 @@ unsigned long uncached_alloc_page(int st
do {
if (!node_online(nid))
continue;
- pool = uncached_pool[nid];
- if (pool = NULL)
+ uc_pool = &uncached_pools[nid];
+ if (uc_pool->pool = NULL)
continue;
do {
- uc_addr = gen_pool_alloc(pool, PAGE_SIZE);
+ uc_addr = gen_pool_alloc(uc_pool->pool, PAGE_SIZE);
if (uc_addr != 0)
return uc_addr;
- } while (uncached_add_chunk(pool, nid) = 0);
+ } while (uncached_add_chunk(uc_pool, nid) = 0);

} while ((nid = (nid + 1) % MAX_NUMNODES) != starting_nid);

@@ -197,7 +224,7 @@ EXPORT_SYMBOL(uncached_alloc_page);
void uncached_free_page(unsigned long uc_addr)
{
int nid = paddr_to_nid(uc_addr - __IA64_UNCACHED_OFFSET);
- struct gen_pool *pool = uncached_pool[nid];
+ struct gen_pool *pool = uncached_pools[nid].pool;

if (unlikely(pool = NULL))
return;
@@ -224,7 +251,7 @@ static int __init uncached_build_memmap(
unsigned long uc_end, void *arg)
{
int nid = paddr_to_nid(uc_start - __IA64_UNCACHED_OFFSET);
- struct gen_pool *pool = uncached_pool[nid];
+ struct gen_pool *pool = uncached_pools[nid].pool;
size_t size = uc_end - uc_start;

touch_softlockup_watchdog();
@@ -242,7 +269,8 @@ static int __init uncached_init(void)
int nid;

for_each_online_node(nid) {
- uncached_pool[nid] = gen_pool_create(PAGE_SHIFT, nid);
+ uncached_pools[nid].pool = gen_pool_create(PAGE_SHIFT, nid);
+ mutex_init(&uncached_pools[nid].add_chunk_mutex);
}

efi_memmap_walk_uc(uncached_build_memmap, NULL);