Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 285 insertions, 0 deletions

diff --git a/mm/percpu-internal.h b/mm/percpu-internal.h
new file mode 100644
index 000000000..095d7eaa0
--- /dev/null
+++ b/mm/percpu-internal.h
@@ -0,0 +1,285 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _MM_PERCPU_INTERNAL_H
+#define _MM_PERCPU_INTERNAL_H
+
+#include <linux/types.h>
+#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 */
+	int                     left_free;      /* size of free space along
+						   the left side of the block */
+	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 {
+#ifdef CONFIG_PERCPU_STATS
+	int			nr_alloc;	/* # of allocations */
+	size_t			max_alloc_size; /* largest allocation size */
+#endif
+
+	struct list_head	list;		/* linked to pcpu_slot lists */
+	int			free_bytes;	/* free bytes in the chunk */
+	struct pcpu_block_md	chunk_md;
+	void			*base_addr;	/* base address of this chunk */
+
+	unsigned long		*alloc_map;	/* allocation map */
+	unsigned long		*bound_map;	/* boundary map */
+	struct pcpu_block_md	*md_blocks;	/* metadata blocks */
+
+	void			*data;		/* chunk data */
+	bool			immutable;	/* no [de]population allowed */
+	int			start_offset;	/* the overlap with the previous
+						   region to have a page aligned
+						   base_addr */
+	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 */
+	int                     nr_empty_pop_pages; /* # of empty populated pages */
+	unsigned long		populated[];	/* populated bitmap */
+};
+
+extern spinlock_t pcpu_lock;
+
+extern struct list_head *pcpu_chunk_lists;
+extern int pcpu_nr_slots;
+extern int pcpu_nr_empty_pop_pages[];
+
+extern struct pcpu_chunk *pcpu_first_chunk;
+extern struct pcpu_chunk *pcpu_reserved_chunk;
+
+/**
+ * pcpu_chunk_nr_blocks - converts nr_pages to # of md_blocks
+ * @chunk: chunk of interest
+ *
+ * This conversion is from the number of physical pages that the chunk
+ * serves to the number of bitmap blocks used.
+ */
+static inline int pcpu_chunk_nr_blocks(struct pcpu_chunk *chunk)
+{
+	return chunk->nr_pages * PAGE_SIZE / PCPU_BITMAP_BLOCK_SIZE;
+}
+
+/**
+ * pcpu_nr_pages_to_map_bits - converts the pages to size of bitmap
+ * @pages: number of physical pages
+ *
+ * This conversion is from physical pages to the number of bits
+ * required in the bitmap.
+ */
+static inline int pcpu_nr_pages_to_map_bits(int pages)
+{
+	return pages * PAGE_SIZE / PCPU_MIN_ALLOC_SIZE;
+}
+
+/**
+ * pcpu_chunk_map_bits - helper to convert nr_pages to size of bitmap
+ * @chunk: chunk of interest
+ *
+ * This conversion is from the number of physical pages that the chunk
+ * serves to the number of bits in the bitmap.
+ */
+static inline int pcpu_chunk_map_bits(struct pcpu_chunk *chunk)
+{
+	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>
+
+struct percpu_stats {
+	u64 nr_alloc;		/* lifetime # of allocations */
+	u64 nr_dealloc;		/* lifetime # of deallocations */
+	u64 nr_cur_alloc;	/* current # of allocations */
+	u64 nr_max_alloc;	/* max # of live allocations */
+	u32 nr_chunks;		/* current # of live chunks */
+	u32 nr_max_chunks;	/* max # of live chunks */
+	size_t min_alloc_size;	/* min allocaiton size */
+	size_t max_alloc_size;	/* max allocation size */
+};
+
+extern struct percpu_stats pcpu_stats;
+extern struct pcpu_alloc_info pcpu_stats_ai;
+
+/*
+ * For debug purposes. We don't care about the flexible array.
+ */
+static inline void pcpu_stats_save_ai(const struct pcpu_alloc_info *ai)
+{
+	memcpy(&pcpu_stats_ai, ai, sizeof(struct pcpu_alloc_info));
+
+	/* initialize min_alloc_size to unit_size */
+	pcpu_stats.min_alloc_size = pcpu_stats_ai.unit_size;
+}
+
+/*
+ * pcpu_stats_area_alloc - increment area allocation stats
+ * @chunk: the location of the area being allocated
+ * @size: size of area to allocate in bytes
+ *
+ * CONTEXT:
+ * pcpu_lock.
+ */
+static inline void pcpu_stats_area_alloc(struct pcpu_chunk *chunk, size_t size)
+{
+	lockdep_assert_held(&pcpu_lock);
+
+	pcpu_stats.nr_alloc++;
+	pcpu_stats.nr_cur_alloc++;
+	pcpu_stats.nr_max_alloc =
+		max(pcpu_stats.nr_max_alloc, pcpu_stats.nr_cur_alloc);
+	pcpu_stats.min_alloc_size =
+		min(pcpu_stats.min_alloc_size, size);
+	pcpu_stats.max_alloc_size =
+		max(pcpu_stats.max_alloc_size, size);
+
+	chunk->nr_alloc++;
+	chunk->max_alloc_size = max(chunk->max_alloc_size, size);
+}
+
+/*
+ * pcpu_stats_area_dealloc - decrement allocation stats
+ * @chunk: the location of the area being deallocated
+ *
+ * CONTEXT:
+ * pcpu_lock.
+ */
+static inline void pcpu_stats_area_dealloc(struct pcpu_chunk *chunk)
+{
+	lockdep_assert_held(&pcpu_lock);
+
+	pcpu_stats.nr_dealloc++;
+	pcpu_stats.nr_cur_alloc--;
+
+	chunk->nr_alloc--;
+}
+
+/*
+ * pcpu_stats_chunk_alloc - increment chunk stats
+ */
+static inline void pcpu_stats_chunk_alloc(void)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&pcpu_lock, flags);
+
+	pcpu_stats.nr_chunks++;
+	pcpu_stats.nr_max_chunks =
+		max(pcpu_stats.nr_max_chunks, pcpu_stats.nr_chunks);
+
+	spin_unlock_irqrestore(&pcpu_lock, flags);
+}
+
+/*
+ * pcpu_stats_chunk_dealloc - decrement chunk stats
+ */
+static inline void pcpu_stats_chunk_dealloc(void)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&pcpu_lock, flags);
+
+	pcpu_stats.nr_chunks--;
+
+	spin_unlock_irqrestore(&pcpu_lock, flags);
+}
+
+#else
+
+static inline void pcpu_stats_save_ai(const struct pcpu_alloc_info *ai)
+{
+}
+
+static inline void pcpu_stats_area_alloc(struct pcpu_chunk *chunk, size_t size)
+{
+}
+
+static inline void pcpu_stats_area_dealloc(struct pcpu_chunk *chunk)
+{
+}
+
+static inline void pcpu_stats_chunk_alloc(void)
+{
+}
+
+static inline void pcpu_stats_chunk_dealloc(void)
+{
+}
+
+#endif /* !CONFIG_PERCPU_STATS */
+
+#endif