[PATCH v3 2/4] mm: zswap: refactor limit checking from zswap_store()

From: Yosry Ahmed
Date: Fri Apr 12 2024 - 22:24:38 EST


Refactor limit and acceptance threshold checking outside of
zswap_store(). This code will be moved around in a following patch, so
it would be cleaner to move a function call around.

Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
---
mm/zswap.c | 32 ++++++++++++++++----------------
1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index 77b6bb2099763..7cddbca3ac62c 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -517,6 +517,21 @@ unsigned long zswap_total_pages(void)
return total;
}

+static bool zswap_check_limits(void)
+{
+ unsigned long cur_pages = zswap_total_pages();
+ unsigned long max_pages = zswap_max_pages();
+
+ if (cur_pages >= max_pages) {
+ zswap_pool_limit_hit++;
+ zswap_pool_reached_full = true;
+ } else if (zswap_pool_reached_full &&
+ cur_pages <= zswap_accept_thr_pages()) {
+ zswap_pool_reached_full = false;
+ }
+ return zswap_pool_reached_full;
+}
+
/*********************************
* param callbacks
**********************************/
@@ -1399,7 +1414,6 @@ bool zswap_store(struct folio *folio)
struct zswap_entry *entry, *old;
struct obj_cgroup *objcg = NULL;
struct mem_cgroup *memcg = NULL;
- unsigned long max_pages, cur_pages;

VM_WARN_ON_ONCE(!folio_test_locked(folio));
VM_WARN_ON_ONCE(!folio_test_swapcache(folio));
@@ -1422,22 +1436,8 @@ bool zswap_store(struct folio *folio)
mem_cgroup_put(memcg);
}

- /* Check global limits */
- cur_pages = zswap_total_pages();
- max_pages = zswap_max_pages();
-
- if (cur_pages >= max_pages) {
- zswap_pool_limit_hit++;
- zswap_pool_reached_full = true;
+ if (zswap_check_limits())
goto reject;
- }
-
- if (zswap_pool_reached_full) {
- if (cur_pages > zswap_accept_thr_pages())
- goto reject;
- else
- zswap_pool_reached_full = false;
- }

/* allocate entry */
entry = zswap_entry_cache_alloc(GFP_KERNEL, folio_nid(folio));
--
2.44.0.683.g7961c838ac-goog