[PATCH v4 08/17] mm/slab_common: kmalloc_node: pass large requests to page allocator

Hyeonggon Yoo
2022-08-17T10:19:34Z

Now that kmalloc_large_node() is in common code, pass large requests
to page allocator in kmalloc_node() using kmalloc_large_node().

One problem is that currently there is no tracepoint in
kmalloc_large_node(). Instead of simply putting tracepoint in it,
use kmalloc_large_node{,_notrace} depending on its caller to show
useful address for both inlined kmalloc_node() and
__kmalloc_node_track_caller() when large objects are allocated.

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
---
include/linux/slab.h | 26 +++++++++++++++++++-------
mm/slab.h | 2 ++
mm/slab_common.c | 11 ++++++++++-
mm/slub.c | 2 +-
4 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/include/linux/slab.h b/include/linux/slab.h
index 082499306098..fd2e129fc813 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -571,23 +571,35 @@ static __always_inline __alloc_size(1) void *kmalloc(size_t size, gfp_t flags)
return __kmalloc(size, flags);
}

+#ifndef CONFIG_SLOB
static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node)
{
-#ifndef CONFIG_SLOB
- if (__builtin_constant_p(size) &&
- size <= KMALLOC_MAX_CACHE_SIZE) {
- unsigned int i = kmalloc_index(size);
+ if (__builtin_constant_p(size)) {
+ unsigned int index;

- if (!i)
+ if (size > KMALLOC_MAX_CACHE_SIZE)
+ return kmalloc_large_node(size, flags, node);
+
+ index = kmalloc_index(size);
+
+ if (!index)
return ZERO_SIZE_PTR;

return kmem_cache_alloc_node_trace(
- kmalloc_caches[kmalloc_type(flags)][i],
+ kmalloc_caches[kmalloc_type(flags)][index],
flags, node, size);
}
-#endif
return __kmalloc_node(size, flags, node);
}
+#else
+static __always_inline __alloc_size(1) void *kmalloc_node(size_t size, gfp_t flags, int node)
+{
+ if (__builtin_constant_p(size) && size > KMALLOC_MAX_CACHE_SIZE)
+ return kmalloc_large_node(size, flags, node);
+
+ return __kmalloc_node(size, flags, node);
+}
+#endif

/**
* kmalloc_array - allocate memory for an array.
diff --git a/mm/slab.h b/mm/slab.h
index 4ec82bec15ec..40322bcf07be 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -273,6 +273,8 @@ void create_kmalloc_caches(slab_flags_t);

/* Find the kmalloc slab corresponding for a certain size */
struct kmem_cache *kmalloc_slab(size_t, gfp_t);
+
+void *kmalloc_large_node_notrace(size_t size, gfp_t flags, int node);
#endif

gfp_t kmalloc_fix_flags(gfp_t flags);
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 1b9101f9cb21..7a0942d54424 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -928,7 +928,7 @@ void *kmalloc_large(size_t size, gfp_t flags)
}
EXPORT_SYMBOL(kmalloc_large);

-void *kmalloc_large_node(size_t size, gfp_t flags, int node)
+void *kmalloc_large_node_notrace(size_t size, gfp_t flags, int node)
{
struct page *page;
void *ptr = NULL;
@@ -948,6 +948,15 @@ void *kmalloc_large_node(size_t size, gfp_t flags, int node)

return ptr;
}
+
+void *kmalloc_large_node(size_t size, gfp_t flags, int node)
+{
+ void *ret = kmalloc_large_node_notrace(size, flags, node);
+
+ trace_kmalloc_node(_RET_IP_, ret, NULL, size,
+ PAGE_SIZE << get_order(size), flags, node);
+ return ret;
+}
EXPORT_SYMBOL(kmalloc_large_node);

#ifdef CONFIG_SLAB_FREELIST_RANDOM
diff --git a/mm/slub.c b/mm/slub.c
index 5e7819ade2c4..165fe87af204 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4401,7 +4401,7 @@ void *__do_kmalloc_node(size_t size, gfp_t flags, int node, unsigned long caller
void *ret;

if (unlikely(size > KMALLOC_MAX_CACHE_SIZE)) {
- ret = kmalloc_large_node(size, flags, node);
+ ret = kmalloc_large_node_notrace(size, flags, node);

trace_kmalloc_node(caller, ret, NULL,
size, PAGE_SIZE << get_order(size),
--
2.32.0