From 9f24ca00d1e6af761f628e70d50c572b86df999e Mon Sep 17 00:00:00 2001
From: Andrea Mazzoleni <amadvance@gmail.com>
Date: Sat, 3 Oct 2026 17:28:26 +0200
Subject: [PATCH] Use atomic operations instead of mutex for memory allocation
 counter

---
 cmdline/memory.c  | 49 +++++++++++++++++++++++++++++++----------------
 cmdline/memory.h  |  5 +++++
 cmdline/state.c   |  3 ++-
 cmdline/support.c | 17 ----------------
 cmdline/support.h |  6 ------
 5 files changed, 40 insertions(+), 40 deletions(-)

diff --git a/cmdline/memory.c b/cmdline/memory.c
index 5a005fff..f2c395a3 100644
--- a/cmdline/memory.c
+++ b/cmdline/memory.c
@@ -14,28 +14,45 @@
  */
 static size_t mcounter;
 
+#if HAVE_THREAD
+static int memory_is_single_thread;
+
+void memory_single_thread(int single_thread)
+{
+	memory_is_single_thread = single_thread;
+}
+
+static inline void malloc_counter_inc(size_t inc)
+{
+	if (tommy_likely(memory_is_single_thread))
+		mcounter += inc;
+	else
+		__atomic_fetch_add(&mcounter, inc, __ATOMIC_RELAXED);
+}
+
 size_t malloc_counter_get(void)
 {
-	size_t ret;
-
-	lock_memory();
-
-	ret = mcounter;
-
-	unlock_memory();
-
-	return ret;
+	if (tommy_likely(memory_is_single_thread))
+		return mcounter;
+	return __atomic_load_n(&mcounter, __ATOMIC_RELAXED);
 }
-
-static void malloc_counter_inc(size_t inc)
+#else
+void memory_single_thread(int single_thread)
 {
-	lock_memory();
-
-	mcounter += inc;
-
-	unlock_memory();
+	(void)single_thread;
 }
 
+static inline void malloc_counter_inc(size_t inc)
+{
+	mcounter += inc;
+}
+
+size_t malloc_counter_get(void)
+{
+	return mcounter;
+}
+#endif
+
 /* LCOV_EXCL_START */
 static ssize_t malloc_print(int f, const char* str)
 {
diff --git a/cmdline/memory.h b/cmdline/memory.h
index 76950e67..0d05f376 100644
--- a/cmdline/memory.h
+++ b/cmdline/memory.h
@@ -12,6 +12,11 @@
  */
 size_t malloc_counter_get(void);
 
+/**
+ * Enable or disable single-thread mode for memory counters.
+ */
+void memory_single_thread(int single_thread);
+
 /**
  * Safe malloc.
  * If no memory is available, it aborts.
diff --git a/cmdline/state.c b/cmdline/state.c
index 9f504e21..c9c83ff0 100644
--- a/cmdline/state.c
+++ b/cmdline/state.c
@@ -2477,6 +2477,8 @@ static int state_read_block_run(STREAM* f, struct snapraid_file* file, block_off
  */
 static void fs_single_thread(struct snapraid_state* state, int single_thread)
 {
+	memory_single_thread(single_thread);
+
 #if HAVE_THREAD
 	for (tommy_node* i = state->disklist; i != 0; i = i->next) {
 		struct snapraid_disk* disk = i->data;
@@ -2484,7 +2486,6 @@ static void fs_single_thread(struct snapraid_state* state, int single_thread)
 	}
 #else
 	(void)state;
-	(void)single_thread;
 #endif
 }
 
diff --git a/cmdline/support.c b/cmdline/support.c
index ae01598c..bbb91d7d 100644
--- a/cmdline/support.c
+++ b/cmdline/support.c
@@ -52,7 +52,6 @@ char* esc_buf(void)
  */
 #if HAVE_THREAD
 static thread_mutex_t msg_lock;
-static thread_mutex_t memory_lock;
 static thread_mutex_t random_lock;
 #endif
 
@@ -70,20 +69,6 @@ void unlock_msg(void)
 #endif
 }
 
-void lock_memory(void)
-{
-#if HAVE_THREAD
-	thread_mutex_lock(&memory_lock);
-#endif
-}
-
-void unlock_memory(void)
-{
-#if HAVE_THREAD
-	thread_mutex_unlock(&memory_lock);
-#endif
-}
-
 void lock_random(void)
 {
 #if HAVE_THREAD
@@ -103,7 +88,6 @@ void lock_init(void)
 #if HAVE_THREAD
 	/* initialize the locks as first operation as log_fatal depends on them */
 	thread_mutex_init(&msg_lock);
-	thread_mutex_init(&memory_lock);
 	thread_mutex_init(&random_lock);
 	thread_key_create(&esc_key, esc_pool_free);
 #endif
@@ -119,7 +103,6 @@ void lock_done(void)
 	}
 	thread_key_delete(esc_key);
 	thread_mutex_destroy(&msg_lock);
-	thread_mutex_destroy(&memory_lock);
 	thread_mutex_destroy(&random_lock);
 #endif
 }
diff --git a/cmdline/support.h b/cmdline/support.h
index 995901f8..34f945b0 100644
--- a/cmdline/support.h
+++ b/cmdline/support.h
@@ -36,12 +36,6 @@ void lock_done(void);
 void lock_msg(void);
 void unlock_msg(void);
 
-/**
- * Lock used for memory counter.
- */
-void lock_memory(void);
-void unlock_memory(void);
-
 /****************************************************************************/
 /* random */