[slubllv4 16/16] slub: update statistics for cmpxchg handling

Christoph Lameter
2011-05-06T18:07:08Z

[-- Attachment #1: statfixes --]
[-- Type: text/plain, Size: 9712 bytes --]

Update the statistics handling and the slabinfo tool to include the new
statistics in the reports it generates.

Signed-off-by: Christoph Lameter <cl@linux.com>

---
include/linux/slub_def.h | 2 +
mm/slub.c | 12 ++++++++-
tools/slub/slabinfo.c | 57 ++++++++++++++++++++++++++++++++---------------
3 files changed, 51 insertions(+), 20 deletions(-)

Index: linux-2.6/include/linux/slub_def.h
===================================================================
--- linux-2.6.orig/include/linux/slub_def.h 2011-05-06 12:54:31.000000000 -0500
+++ linux-2.6/include/linux/slub_def.h 2011-05-06 12:57:25.000000000 -0500
@@ -24,6 +24,7 @@ enum stat_item {
ALLOC_FROM_PARTIAL, /* Cpu slab acquired from partial list */
ALLOC_SLAB, /* Cpu slab acquired from page allocator */
ALLOC_REFILL, /* Refill cpu slab from slab freelist */
+ ALLOC_NODE_MISMATCH, /* Switching cpu slab */
FREE_SLAB, /* Slab freed to the page allocator */
CPUSLAB_FLUSH, /* Abandoning of the cpu slab */
DEACTIVATE_FULL, /* Cpu slab was full when deactivated */
@@ -31,6 +32,7 @@ enum stat_item {
DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */
DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */
DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
+ DEACTIVATE_BYPASS, /* Implicit deactivation */
ORDER_FALLBACK, /* Number of times fallback was necessary */
CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */
Index: linux-2.6/mm/slub.c
===================================================================
--- linux-2.6.orig/mm/slub.c 2011-05-06 12:57:10.000000000 -0500
+++ linux-2.6/mm/slub.c 2011-05-06 12:57:25.000000000 -0500
@@ -1774,6 +1774,7 @@ redo:
spin_unlock(&n->list_lock);

if (m == M_FREE) {
+ stat(s, DEACTIVATE_EMPTY);
discard_slab(s, page);
stat(s, FREE_SLAB);
}
@@ -1929,12 +1930,12 @@ static void *__slab_alloc(struct kmem_ca
goto new_slab;

if (unlikely(!node_match(c, node))) {
+ stat(s, ALLOC_NODE_MISMATCH);
deactivate_slab(s, c);
goto new_slab;
}

- stat(s, ALLOC_REFILL);
-
+ stat(s, ALLOC_SLOWPATH);
{
struct page new;
unsigned long counters;
@@ -1966,9 +1967,12 @@ static void *__slab_alloc(struct kmem_ca

if (unlikely(!object)) {
c->page = NULL;
+ stat(s, DEACTIVATE_BYPASS);
goto new_slab;
}

+ stat(s, ALLOC_REFILL);
+
load_freelist:
VM_BUG_ON(!page->frozen);
c->freelist = get_freepointer(s, object);
@@ -4671,6 +4675,7 @@ STAT_ATTR(FREE_REMOVE_PARTIAL, free_remo
STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial);
STAT_ATTR(ALLOC_SLAB, alloc_slab);
STAT_ATTR(ALLOC_REFILL, alloc_refill);
+STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch);
STAT_ATTR(FREE_SLAB, free_slab);
STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush);
STAT_ATTR(DEACTIVATE_FULL, deactivate_full);
@@ -4678,6 +4683,7 @@ STAT_ATTR(DEACTIVATE_EMPTY, deactivate_e
STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head);
STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail);
STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees);
+STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass);
STAT_ATTR(ORDER_FALLBACK, order_fallback);
STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail);
STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail);
@@ -4730,6 +4736,7 @@ static struct attribute *slab_attrs[] =
&alloc_from_partial_attr.attr,
&alloc_slab_attr.attr,
&alloc_refill_attr.attr,
+ &alloc_node_mismatch_attr.attr,
&free_slab_attr.attr,
&cpuslab_flush_attr.attr,
&deactivate_full_attr.attr,
@@ -4737,6 +4744,7 @@ static struct attribute *slab_attrs[] =
&deactivate_to_head_attr.attr,
&deactivate_to_tail_attr.attr,
&deactivate_remote_frees_attr.attr,
+ &deactivate_bypass_attr.attr,
&order_fallback_attr.attr,
&cmpxchg_double_fail_attr.attr,
&cmpxchg_double_cpu_fail_attr.attr,
Index: linux-2.6/tools/slub/slabinfo.c
===================================================================
--- linux-2.6.orig/tools/slub/slabinfo.c 2011-05-06 12:41:41.000000000 -0500
+++ linux-2.6/tools/slub/slabinfo.c 2011-05-06 12:57:25.000000000 -0500
@@ -2,8 +2,9 @@
* Slabinfo: Tool to get reports about slabs
*
* (C) 2007 sgi, Christoph Lameter
+ * (C) 2011 Linux Foundation, Christoph Lameter
*
- * Compile by:
+ * Compile with:
*
* gcc -o slabinfo slabinfo.c
*/
@@ -39,6 +40,8 @@ struct slabinfo {
unsigned long cpuslab_flush, deactivate_full, deactivate_empty;
unsigned long deactivate_to_head, deactivate_to_tail;
unsigned long deactivate_remote_frees, order_fallback;
+ unsigned long cmpxchg_double_cpu_fail, cmpxchg_double_fail;
+ unsigned long alloc_node_mismatch, deactivate_bypass;
int numa[MAX_NODES];
int numa_partial[MAX_NODES];
} slabinfo[MAX_SLABS];
@@ -99,7 +102,7 @@ static void fatal(const char *x, ...)

static void usage(void)
{
- printf("slabinfo 5/7/2007. (c) 2007 sgi.\n\n"
+ printf("slabinfo 4/15/2011. (c) 2007 sgi/(c) 2011 Linux Foundation.\n\n"
"slabinfo [-ahnpvtsz] [-d debugopts] [slab-regexp]\n"
"-a|--aliases Show aliases\n"
"-A|--activity Most active slabs first\n"
@@ -293,7 +296,7 @@ int line = 0;
static void first_line(void)
{
if (show_activity)
- printf("Name Objects Alloc Free %%Fast Fallb O\n");
+ printf("Name Objects Alloc Free %%Fast Fallb O CmpX UL\n");
else
printf("Name Objects Objsize Space "
"Slabs/Part/Cpu O/S O %%Fr %%Ef Flg\n");
@@ -379,14 +382,14 @@ static void show_tracking(struct slabinf
printf("\n%s: Kernel object allocation\n", s->name);
printf("-----------------------------------------------------------------------\n");
if (read_slab_obj(s, "alloc_calls"))
- printf(buffer);
+ printf("%s", buffer);
else
printf("No Data\n");

printf("\n%s: Kernel object freeing\n", s->name);
printf("------------------------------------------------------------------------\n");
if (read_slab_obj(s, "free_calls"))
- printf(buffer);
+ printf("%s", buffer);
else
printf("No Data\n");

@@ -400,7 +403,7 @@ static void ops(struct slabinfo *s)
if (read_slab_obj(s, "ops")) {
printf("\n%s: kmem_cache operations\n", s->name);
printf("--------------------------------------------\n");
- printf(buffer);
+ printf("%s", buffer);
} else
printf("\n%s has no kmem_cache operations\n", s->name);
}
@@ -462,19 +465,32 @@ static void slab_stats(struct slabinfo *
if (s->cpuslab_flush)
printf("Flushes %8lu\n", s->cpuslab_flush);

- if (s->alloc_refill)
- printf("Refill %8lu\n", s->alloc_refill);
-
total = s->deactivate_full + s->deactivate_empty +
- s->deactivate_to_head + s->deactivate_to_tail;
+ s->deactivate_to_head + s->deactivate_to_tail + s->deactivate_bypass;

- if (total)
- printf("Deactivate Full=%lu(%lu%%) Empty=%lu(%lu%%) "
- "ToHead=%lu(%lu%%) ToTail=%lu(%lu%%)\n",
- s->deactivate_full, (s->deactivate_full * 100) / total,
- s->deactivate_empty, (s->deactivate_empty * 100) / total,
- s->deactivate_to_head, (s->deactivate_to_head * 100) / total,
+ if (total) {
+ printf("\nSlab Deactivation Ocurrences %%\n");
+ printf("-------------------------------------------------\n");
+ printf("Slab full %7lu %3lu%%\n",
+ s->deactivate_full, (s->deactivate_full * 100) / total);
+ printf("Slab empty %7lu %3lu%%\n",
+ s->deactivate_empty, (s->deactivate_empty * 100) / total);
+ printf("Moved to head of partial list %7lu %3lu%%\n",
+ s->deactivate_to_head, (s->deactivate_to_head * 100) / total);
+ printf("Moved to tail of partial list %7lu %3lu%%\n",
s->deactivate_to_tail, (s->deactivate_to_tail * 100) / total);
+ printf("Deactivation bypass %7lu %3lu%%\n",
+ s->deactivate_bypass, (s->deactivate_bypass * 100) / total);
+ printf("Refilled from foreign frees %7lu %3lu%%\n",
+ s->alloc_refill, (s->alloc_refill * 100) / total);
+ printf("Node mismatch %7lu %3lu%%\n",
+ s->alloc_node_mismatch, (s->alloc_node_mismatch * 100) / total);
+ }
+
+ if (s->cmpxchg_double_fail || s->cmpxchg_double_cpu_fail)
+ printf("\nCmpxchg_double Looping\n------------------------\n");
+ printf("Locked Cmpxchg Double redos %lu\nUnlocked Cmpxchg Double redos %lu\n",
+ s->cmpxchg_double_fail, s->cmpxchg_double_cpu_fail);
}

static void report(struct slabinfo *s)
@@ -573,12 +589,13 @@ static void slabcache(struct slabinfo *s
total_alloc = s->alloc_fastpath + s->alloc_slowpath;
total_free = s->free_fastpath + s->free_slowpath;

- printf("%-21s %8ld %10ld %10ld %3ld %3ld %5ld %1d\n",
+ printf("%-21s %8ld %10ld %10ld %3ld %3ld %5ld %1d %4ld %4ld\n",
s->name, s->objects,
total_alloc, total_free,
total_alloc ? (s->alloc_fastpath * 100 / total_alloc) : 0,
total_free ? (s->free_fastpath * 100 / total_free) : 0,
- s->order_fallback, s->order);
+ s->order_fallback, s->order, s->cmpxchg_double_fail,
+ s->cmpxchg_double_cpu_fail);
}
else
printf("%-21s %8ld %7d %8s %14s %4d %1d %3ld %3ld %s\n",
@@ -1190,6 +1207,10 @@ static void read_slab_dir(void)
slab->deactivate_to_tail = get_obj("deactivate_to_tail");
slab->deactivate_remote_frees = get_obj("deactivate_remote_frees");
slab->order_fallback = get_obj("order_fallback");
+ slab->cmpxchg_double_cpu_fail = get_obj("cmpxchg_double_cpu_fail");
+ slab->cmpxchg_double_fail = get_obj("cmpxchg_double_fail");
+ slab->alloc_node_mismatch = get_obj("alloc_node_mismatch");
+ slab->deactivate_bypass = get_obj("deactivate_bypass");
chdir("..");
if (slab->name[0] == ':')
alias_targets++;