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-rw-r--r--debian/patches/ext2fs-optimize-bcache0003-ext2fs-keep-list-of-reusable-disk-cache-entries.patch187
1 files changed, 0 insertions, 187 deletions
diff --git a/debian/patches/ext2fs-optimize-bcache0003-ext2fs-keep-list-of-reusable-disk-cache-entries.patch b/debian/patches/ext2fs-optimize-bcache0003-ext2fs-keep-list-of-reusable-disk-cache-entries.patch
deleted file mode 100644
index 2ee46c07..00000000
--- a/debian/patches/ext2fs-optimize-bcache0003-ext2fs-keep-list-of-reusable-disk-cache-entries.patch
+++ /dev/null
@@ -1,187 +0,0 @@
-From e68df91a9fbeba5ee6ec311a996f74132de1d34c Mon Sep 17 00:00:00 2001
-From: Justus Winter <4winter@informatik.uni-hamburg.de>
-Date: Sun, 22 Nov 2015 20:19:52 +0100
-Subject: [PATCH hurd 3/3] ext2fs: keep list of reusable disk cache entries
-
-This avoids a linear scan through the cache.
-
-* ext2fs/ext2fs.h (struct disk_cache_info): New field 'next'.
-* ext2fs/pager.c (disk_cache_hint): Drop.
-(disk_cache_info_free, disk_cache_info_free_lock): New variables.
-(disk_cache_info_free_pop, disk_cache_info_free_push): New functions.
-(disk_cache_init): Adjust slightly.
-(disk_cache_block_ref): Use new functions.
-(disk_cache_block_deref): Likewise.
----
- ext2fs/ext2fs.h | 1 +
- ext2fs/pager.c | 83 ++++++++++++++++++++++++++++++++++++---------------------
- 2 files changed, 53 insertions(+), 31 deletions(-)
-
-diff --git a/ext2fs/ext2fs.h b/ext2fs/ext2fs.h
-index 0b6b79e..b839819 100644
---- a/ext2fs/ext2fs.h
-+++ b/ext2fs/ext2fs.h
-@@ -254,6 +254,7 @@ struct disk_cache_info
- block_t block;
- uint16_t flags;
- uint16_t ref_count;
-+ struct disk_cache_info *next; /* List of reusable entries. */
- #ifdef DEBUG_DISK_CACHE
- block_t last_read, last_read_xor;
- #endif
-diff --git a/ext2fs/pager.c b/ext2fs/pager.c
-index f28bcab..47c5f94 100644
---- a/ext2fs/pager.c
-+++ b/ext2fs/pager.c
-@@ -840,13 +840,50 @@ int disk_cache_blocks;
- hurd_ihash_t disk_cache_bptr;
- /* Cached blocks' info. */
- struct disk_cache_info *disk_cache_info;
--/* Hint index for which cache block to reuse next. */
--int disk_cache_hint;
- /* Lock for these structures. */
- pthread_mutex_t disk_cache_lock;
- /* Fired when a re-association is done. */
- pthread_cond_t disk_cache_reassociation;
-
-+/* Linked list of potentially unused blocks. */
-+static struct disk_cache_info *disk_cache_info_free;
-+static pthread_mutex_t disk_cache_info_free_lock;
-+
-+/* Get a reusable entry. Must be called with disk_cache_lock
-+ held. */
-+static struct disk_cache_info *
-+disk_cache_info_free_pop (void)
-+{
-+ struct disk_cache_info *p;
-+
-+ do
-+ {
-+ pthread_mutex_lock (&disk_cache_info_free_lock);
-+ p = disk_cache_info_free;
-+ if (p)
-+ {
-+ disk_cache_info_free = p->next;
-+ p->next = NULL;
-+ }
-+ pthread_mutex_unlock (&disk_cache_info_free_lock);
-+ }
-+ while (p && (p->flags & DC_DONT_REUSE || p->ref_count > 0));
-+ return p;
-+}
-+
-+/* Add P to the list of potentially re-usable entries. */
-+static void
-+disk_cache_info_free_push (struct disk_cache_info *p)
-+{
-+ pthread_mutex_lock (&disk_cache_info_free_lock);
-+ if (! p->next)
-+ {
-+ p->next = disk_cache_info_free;
-+ disk_cache_info_free = p;
-+ }
-+ pthread_mutex_unlock (&disk_cache_info_free_lock);
-+}
-+
- /* Finish mapping initialization. */
- static void
- disk_cache_init (void)
-@@ -857,6 +894,7 @@ disk_cache_init (void)
-
- pthread_mutex_init (&disk_cache_lock, NULL);
- pthread_cond_init (&disk_cache_reassociation, NULL);
-+ pthread_mutex_init (&disk_cache_info_free_lock, NULL);
-
- /* Allocate space for block num -> in-memory pointer mapping. */
- if (hurd_ihash_create (&disk_cache_bptr, HURD_IHASH_NO_LOCP))
-@@ -867,19 +905,22 @@ disk_cache_init (void)
- if (!disk_cache_info)
- ext2_panic ("Cannot allocate space for disk cache info");
-
-- /* Initialize disk_cache_info. */
-- for (int i = 0; i < disk_cache_blocks; i++)
-+ /* Initialize disk_cache_info. Start with the last entry so that
-+ the first ends up at the front of the free list. This keeps the
-+ assertions at the end of this function happy. */
-+ for (int i = disk_cache_blocks; i >= 0; i--)
- {
- disk_cache_info[i].block = DC_NO_BLOCK;
- disk_cache_info[i].flags = 0;
- disk_cache_info[i].ref_count = 0;
-+ disk_cache_info[i].next = NULL;
-+ disk_cache_info_free_push (&disk_cache_info[i]);
- #ifdef DEBUG_DISK_CACHE
- disk_cache_info[i].last_read = DC_NO_BLOCK;
- disk_cache_info[i].last_read_xor
- = DC_NO_BLOCK ^ DISK_CACHE_LAST_READ_XOR;
- #endif
- }
-- disk_cache_hint = 0;
-
- /* Map the superblock and the block group descriptors. */
- block_t fixed_first = boffs_block (SBLOCK_OFFS);
-@@ -958,6 +999,7 @@ disk_cache_return_unused (void)
- void *
- disk_cache_block_ref (block_t block)
- {
-+ struct disk_cache_info *info;
- int index;
- void *bptr;
- hurd_ihash_locp_t slot;
-@@ -1005,34 +1047,10 @@ retry_ref:
- }
-
- /* Search for a block that is not in core and is not referenced. */
-- index = disk_cache_hint;
-- while ((disk_cache_info[index].flags & DC_DONT_REUSE)
-- || (disk_cache_info[index].ref_count))
-- {
-- ext2_debug ("reject %u -> %d (ref_count = %hu, flags = %#hx)",
-- disk_cache_info[index].block, index,
-- disk_cache_info[index].ref_count,
-- disk_cache_info[index].flags);
--
-- /* Just move to next block. */
-- index++;
-- if (index >= disk_cache_blocks)
-- index -= disk_cache_blocks;
--
-- /* If we return to where we started, than there is no suitable
-- block. */
-- if (index == disk_cache_hint)
-- break;
-- }
--
-- /* The next place in the disk cache becomes the current hint. */
-- disk_cache_hint = index + 1;
-- if (disk_cache_hint >= disk_cache_blocks)
-- disk_cache_hint -= disk_cache_blocks;
-+ info = disk_cache_info_free_pop ();
-
- /* Is suitable place found? */
-- if ((disk_cache_info[index].flags & DC_DONT_REUSE)
-- || disk_cache_info[index].ref_count)
-+ if (info == NULL)
- /* No place is found. Try to release some blocks and try
- again. */
- {
-@@ -1046,6 +1064,7 @@ retry_ref:
- }
-
- /* Suitable place is found. */
-+ index = info - disk_cache_info;
-
- /* Calculate pointer to data. */
- bptr = (char *)disk_cache + (index << log2_block_size);
-@@ -1177,6 +1196,8 @@ disk_cache_block_deref (void *ptr)
- assert (! (disk_cache_info[index].flags & DC_UNTOUCHED));
- assert (disk_cache_info[index].ref_count >= 1);
- disk_cache_info[index].ref_count--;
-+ if (disk_cache_info[index].ref_count == 0)
-+ disk_cache_info_free_push (&disk_cache_info[index]);
- pthread_mutex_unlock (&disk_cache_lock);
- }
-
---
-2.1.4
-
generated by cgit v1.2.3 (git 2.46.0) at 2025-04-26 13:27:48 +0000