From 102a0743326a03cd1a1202ceda21e175b7d3575c Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:20:52 +0000
Subject: [PATCH] add new system file
---
kernel/mm/percpu-internal.h | 72 +++++++++++++++++++++++++++++++++---
1 files changed, 66 insertions(+), 6 deletions(-)
diff --git a/kernel/mm/percpu-internal.h b/kernel/mm/percpu-internal.h
index b1739dc..095d7ea 100644
--- a/kernel/mm/percpu-internal.h
+++ b/kernel/mm/percpu-internal.h
@@ -6,11 +6,39 @@
#include <linux/percpu.h>
/*
+ * There are two chunk types: root and memcg-aware.
+ * Chunks of each type have separate slots list.
+ *
+ * Memcg-aware chunks have an attached vector of obj_cgroup pointers, which is
+ * used to store memcg membership data of a percpu object. Obj_cgroups are
+ * ref-counted pointers to a memory cgroup with an ability to switch dynamically
+ * to the parent memory cgroup. This allows to reclaim a deleted memory cgroup
+ * without reclaiming of all outstanding objects, which hold a reference at it.
+ */
+enum pcpu_chunk_type {
+ PCPU_CHUNK_ROOT,
+#ifdef CONFIG_MEMCG_KMEM
+ PCPU_CHUNK_MEMCG,
+#endif
+ PCPU_NR_CHUNK_TYPES,
+ PCPU_FAIL_ALLOC = PCPU_NR_CHUNK_TYPES
+};
+
+/*
* pcpu_block_md is the metadata block struct.
* Each chunk's bitmap is split into a number of full blocks.
* All units are in terms of bits.
+ *
+ * The scan hint is the largest known contiguous area before the contig hint.
+ * It is not necessarily the actual largest contig hint though. There is an
+ * invariant that the scan_hint_start > contig_hint_start iff
+ * scan_hint == contig_hint. This is necessary because when scanning forward,
+ * we don't know if a new contig hint would be better than the current one.
*/
struct pcpu_block_md {
+ int scan_hint; /* scan hint for block */
+ int scan_hint_start; /* block relative starting
+ position of the scan hint */
int contig_hint; /* contig hint for block */
int contig_hint_start; /* block relative starting
position of the contig hint */
@@ -19,6 +47,7 @@
int right_free; /* size of free space along
the right side of the block */
int first_free; /* block position of first free */
+ int nr_bits; /* total bits responsible for */
};
struct pcpu_chunk {
@@ -29,9 +58,7 @@
struct list_head list; /* linked to pcpu_slot lists */
int free_bytes; /* free bytes in the chunk */
- int contig_bits; /* max contiguous size hint */
- int contig_bits_start; /* contig_bits starting
- offset */
+ struct pcpu_block_md chunk_md;
void *base_addr; /* base address of this chunk */
unsigned long *alloc_map; /* allocation map */
@@ -39,7 +66,6 @@
struct pcpu_block_md *md_blocks; /* metadata blocks */
void *data; /* chunk data */
- int first_bit; /* no free below this */
bool immutable; /* no [de]population allowed */
int start_offset; /* the overlap with the previous
region to have a page aligned
@@ -47,6 +73,9 @@
int end_offset; /* additional area required to
have the region end page
aligned */
+#ifdef CONFIG_MEMCG_KMEM
+ struct obj_cgroup **obj_cgroups; /* vector of object cgroups */
+#endif
int nr_pages; /* # of pages served by this chunk */
int nr_populated; /* # of populated pages */
@@ -56,9 +85,9 @@
extern spinlock_t pcpu_lock;
-extern struct list_head *pcpu_slot;
+extern struct list_head *pcpu_chunk_lists;
extern int pcpu_nr_slots;
-extern int pcpu_nr_empty_pop_pages;
+extern int pcpu_nr_empty_pop_pages[];
extern struct pcpu_chunk *pcpu_first_chunk;
extern struct pcpu_chunk *pcpu_reserved_chunk;
@@ -99,6 +128,37 @@
return pcpu_nr_pages_to_map_bits(chunk->nr_pages);
}
+#ifdef CONFIG_MEMCG_KMEM
+static inline enum pcpu_chunk_type pcpu_chunk_type(struct pcpu_chunk *chunk)
+{
+ if (chunk->obj_cgroups)
+ return PCPU_CHUNK_MEMCG;
+ return PCPU_CHUNK_ROOT;
+}
+
+static inline bool pcpu_is_memcg_chunk(enum pcpu_chunk_type chunk_type)
+{
+ return chunk_type == PCPU_CHUNK_MEMCG;
+}
+
+#else
+static inline enum pcpu_chunk_type pcpu_chunk_type(struct pcpu_chunk *chunk)
+{
+ return PCPU_CHUNK_ROOT;
+}
+
+static inline bool pcpu_is_memcg_chunk(enum pcpu_chunk_type chunk_type)
+{
+ return false;
+}
+#endif
+
+static inline struct list_head *pcpu_chunk_list(enum pcpu_chunk_type chunk_type)
+{
+ return &pcpu_chunk_lists[pcpu_nr_slots *
+ pcpu_is_memcg_chunk(chunk_type)];
+}
+
#ifdef CONFIG_PERCPU_STATS
#include <linux/spinlock.h>
--
Gitblit v1.6.2