[PATCH 18/21] bcachefs: bch_acct_compression

[Kent Overstreet]

This adds per-compression-type accounting of compressed and uncompressed
size as well as number of extents - meaning we can now see compression
ratio (without walking the whole filesystem).

Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
---
 fs/bcachefs/buckets.c                | 45 ++++++++++++++++++++++++----
 fs/bcachefs/disk_accounting.c        |  4 +++
 fs/bcachefs/disk_accounting_format.h |  8 ++++-
 3 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/fs/bcachefs/buckets.c b/fs/bcachefs/buckets.c
index 506bb580bff4..6078b67e51cf 100644
--- a/fs/bcachefs/buckets.c
+++ b/fs/bcachefs/buckets.c
@@ -503,6 +503,7 @@ static int __trigger_extent(struct btree_trans *trans,
 		: BCH_DATA_user;
 	s64 dirty_sectors = 0;
 	int ret = 0;
+	u64 compression_acct[3] = { 1, 0, 0 };
 
 	struct disk_accounting_key acc = {
 		.type			= BCH_DISK_ACCOUNTING_replicas,
@@ -511,6 +512,10 @@ static int __trigger_extent(struct btree_trans *trans,
 		.replicas.nr_required	= 1,
 	};
 
+	struct disk_accounting_key compression_key = {
+		.type			= BCH_DISK_ACCOUNTING_compression,
+	};
+
 	bkey_for_each_ptr_decode(k.k, ptrs, p, entry) {
 		s64 disk_sectors;
 		ret = bch2_trigger_pointer(trans, btree_id, level, k, p, &disk_sectors, flags);
@@ -519,12 +524,13 @@ static int __trigger_extent(struct btree_trans *trans,
 
 		bool stale = ret > 0;
 
+		if (p.ptr.cached && stale)
+			continue;
+
 		if (p.ptr.cached) {
-			if (!stale) {
-				ret = bch2_mod_dev_cached_sectors(trans, p.ptr.dev, disk_sectors, gc);
-				if (ret)
-					return ret;
-			}
+			ret = bch2_mod_dev_cached_sectors(trans, p.ptr.dev, disk_sectors, gc);
+			if (ret)
+				return ret;
 		} else if (!p.has_ec) {
 			dirty_sectors	       += disk_sectors;
 			acc.replicas.devs[acc.replicas.nr_devs++] = p.ptr.dev;
@@ -540,6 +546,26 @@ static int __trigger_extent(struct btree_trans *trans,
 			 */
 			acc.replicas.nr_required = 0;
 		}
+
+		if (compression_key.compression.type &&
+		    compression_key.compression.type != p.crc.compression_type) {
+			if (flags & BTREE_TRIGGER_OVERWRITE)
+				bch2_u64s_neg(compression_acct, 3);
+
+			ret = bch2_disk_accounting_mod(trans, &compression_key, compression_acct, 2, gc);
+			if (ret)
+				return ret;
+
+			compression_acct[0] = 1;
+			compression_acct[1] = 0;
+			compression_acct[2] = 0;
+		}
+
+		compression_key.compression.type = p.crc.compression_type;
+		if (p.crc.compression_type) {
+			compression_acct[1] += p.crc.uncompressed_size;
+			compression_acct[2] += p.crc.compressed_size;
+		}
 	}
 
 	if (acc.replicas.nr_devs) {
@@ -548,6 +574,15 @@ static int __trigger_extent(struct btree_trans *trans,
 			return ret;
 	}
 
+	if (compression_key.compression.type) {
+		if (flags & BTREE_TRIGGER_OVERWRITE)
+			bch2_u64s_neg(compression_acct, 3);
+
+		ret = bch2_disk_accounting_mod(trans, &compression_key, compression_acct, 3, gc);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 
diff --git a/fs/bcachefs/disk_accounting.c b/fs/bcachefs/disk_accounting.c
index 8d7b6ab66e71..dc020d651d0a 100644
--- a/fs/bcachefs/disk_accounting.c
+++ b/fs/bcachefs/disk_accounting.c
@@ -5,6 +5,7 @@
 #include "btree_update.h"
 #include "btree_write_buffer.h"
 #include "buckets.h"
+#include "compress.h"
 #include "disk_accounting.h"
 #include "error.h"
 #include "journal_io.h"
@@ -91,6 +92,9 @@ void bch2_accounting_key_to_text(struct printbuf *out, struct disk_accounting_ke
 	case BCH_DISK_ACCOUNTING_dev_stripe_buckets:
 		prt_printf(out, "dev=%u", k->dev_stripe_buckets.dev);
 		break;
+	case BCH_DISK_ACCOUNTING_compression:
+		bch2_prt_compression_type(out, k->compression.type);
+		break;
 	}
 }
 
diff --git a/fs/bcachefs/disk_accounting_format.h b/fs/bcachefs/disk_accounting_format.h
index e06a42f0d578..75bfc9bce79f 100644
--- a/fs/bcachefs/disk_accounting_format.h
+++ b/fs/bcachefs/disk_accounting_format.h
@@ -95,7 +95,8 @@ static inline bool data_type_is_hidden(enum bch_data_type type)
 	x(persistent_reserved,	1)		\
 	x(replicas,		2)		\
 	x(dev_data_type,	3)		\
-	x(dev_stripe_buckets,	4)
+	x(dev_stripe_buckets,	4)		\
+	x(compression,		5)
 
 enum disk_accounting_type {
 #define x(f, nr)	BCH_DISK_ACCOUNTING_##f	= nr,
@@ -120,6 +121,10 @@ struct bch_dev_stripe_buckets {
 	__u8			dev;
 };
 
+struct bch_acct_compression {
+	__u8			type;
+};
+
 struct disk_accounting_key {
 	union {
 	struct {
@@ -130,6 +135,7 @@ struct disk_accounting_key {
 		struct bch_replicas_entry_v1	replicas;
 		struct bch_dev_data_type	dev_data_type;
 		struct bch_dev_stripe_buckets	dev_stripe_buckets;
+		struct bch_acct_compression	compression;
 		};
 	};
 		struct bpos			_pad;
-- 
2.43.0