diff options
| author | Chengming Zhou <zhouchengming@bytedance.com> | 2024-02-04 03:06:02 +0000 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-02-22 10:24:54 -0800 |
| commit | 3b631bd06550040b37cd2ebb00e2374404db0360 (patch) | |
| tree | 835ea3da4b2e8ca21da8768090b88f22c2ec1eb4 | |
| parent | b49547ade38a63ff39c9fbc53fb38622cb63854a (diff) | |
mm/zswap: remove duplicate_entry debug value
cat /sys/kernel/debug/zswap/duplicate_entry
2086447
When testing, the duplicate_entry value is very high, but no warning
message in the kernel log. From the comment of duplicate_entry "Duplicate
store was encountered (rare)", it seems something goes wrong.
Actually it's incremented in the beginning of zswap_store(), which found
its zswap entry has already on the tree. And this is a normal case, since
the folio could leave zswap entry on the tree after swapin, later it's
dirtied and swapout/zswap_store again, found its original zswap entry.
So duplicate_entry should be only incremented in the real bug case, which
already have "WARN_ON(1)", it looks redundant to count bug case, so this
patch just remove it.
Link: https://lkml.kernel.org/r/20240201-b4-zswap-invalidate-entry-v2-4-99d4084260a0@bytedance.com
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/zswap.c | 9 |
1 files changed, 1 insertions, 8 deletions
diff --git a/mm/zswap.c b/mm/zswap.c index f8a4ac389118..91df925359c8 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -71,8 +71,6 @@ static u64 zswap_reject_compress_poor; static u64 zswap_reject_alloc_fail; /* Store failed because the entry metadata could not be allocated (rare) */ static u64 zswap_reject_kmemcache_fail; -/* Duplicate store was encountered (rare) */ -static u64 zswap_duplicate_entry; /* Shrinker work queue */ static struct workqueue_struct *shrink_wq; @@ -1568,10 +1566,8 @@ bool zswap_store(struct folio *folio) */ spin_lock(&tree->lock); entry = zswap_rb_search(&tree->rbroot, offset); - if (entry) { + if (entry) zswap_invalidate_entry(tree, entry); - zswap_duplicate_entry++; - } spin_unlock(&tree->lock); if (!zswap_enabled) @@ -1662,7 +1658,6 @@ insert_entry: */ while (zswap_rb_insert(&tree->rbroot, entry, &dupentry) == -EEXIST) { WARN_ON(1); - zswap_duplicate_entry++; zswap_invalidate_entry(tree, dupentry); } if (entry->length) { @@ -1823,8 +1818,6 @@ static int zswap_debugfs_init(void) zswap_debugfs_root, &zswap_reject_compress_poor); debugfs_create_u64("written_back_pages", 0444, zswap_debugfs_root, &zswap_written_back_pages); - debugfs_create_u64("duplicate_entry", 0444, - zswap_debugfs_root, &zswap_duplicate_entry); debugfs_create_u64("pool_total_size", 0444, zswap_debugfs_root, &zswap_pool_total_size); debugfs_create_atomic_t("stored_pages", 0444, |