lib, kernel: use single evaluation min/max/clamp

fabiobaltieri · fabiobaltieri · commit 35203b133d3c · 2025-10-21T17:17:22.000+01:00
Replace all in-function instances of MIN/MAX/CLAMP with the single
evaluation version min/max/clamp.

There's probably no race conditions in these files, but the single
evaluation ones save a couple of instructions each so they should save
few code bytes and potentially perform better, so they should be
preferred in general.

Signed-off-by: Fabio Baltieri &lt;fabiobaltieri@google.com&gt;
diff --git a/kernel/init.c b/kernel/init.c
@@ -515,7 +515,7 @@ void __weak z_early_rand_get(uint8_t *buf, size_t length)
 		state = state + k_cycle_get_32();
 		state = state * 2862933555777941757ULL + 3037000493ULL;
 		val = (uint32_t)(state >> 32);
-		rc = MIN(length, sizeof(val));
+		rc = min(length, sizeof(val));
 		arch_early_memcpy((void *)buf, &val, rc);
 
 		length -= rc;
diff --git a/kernel/mem_slab.c b/kernel/mem_slab.c
@@ -237,7 +237,7 @@ int k_mem_slab_alloc(struct k_mem_slab *slab, void **mem, k_timeout_t timeout)
 			 "slab corruption detected");
 
 #ifdef CONFIG_MEM_SLAB_TRACE_MAX_UTILIZATION
-		slab->info.max_used = MAX(slab->info.num_used,
+		slab->info.max_used = max(slab->info.num_used,
 					  slab->info.max_used);
 #endif /* CONFIG_MEM_SLAB_TRACE_MAX_UTILIZATION */
 
diff --git a/kernel/mmu.c b/kernel/mmu.c
@@ -274,8 +274,8 @@ static void virt_region_free(void *vaddr, size_t size)
 	     (vaddr_u8 < Z_VIRT_REGION_END_ADDR)) ||
 	    (((vaddr_u8 + size - 1) >= Z_VIRT_REGION_START_ADDR) &&
 	     ((vaddr_u8 + size - 1) < Z_VIRT_REGION_END_ADDR))) {
-		uint8_t *adjusted_start = MAX(vaddr_u8, Z_VIRT_REGION_START_ADDR);
-		uint8_t *adjusted_end = MIN(vaddr_u8 + size,
+		uint8_t *adjusted_start = max(vaddr_u8, Z_VIRT_REGION_START_ADDR);
+		uint8_t *adjusted_end = min(vaddr_u8 + size,
 					    Z_VIRT_REGION_END_ADDR);
 		size_t adjusted_sz = adjusted_end - adjusted_start;
 
@@ -930,8 +930,8 @@ void k_mem_map_phys_bare(uint8_t **virt_ptr, uintptr_t phys, size_t size, uint32
 		    IN_RANGE(aligned_phys + aligned_size - 1,
 			      (uintptr_t)K_MEM_VIRT_RAM_START,
 			      (uintptr_t)(K_MEM_VIRT_RAM_END - 1))) {
-			uint8_t *adjusted_start = MAX(dest_addr, K_MEM_VIRT_RAM_START);
-			uint8_t *adjusted_end = MIN(dest_addr + aligned_size,
+			uint8_t *adjusted_start = max(dest_addr, K_MEM_VIRT_RAM_START);
+			uint8_t *adjusted_end = min(dest_addr + aligned_size,
 						    K_MEM_VIRT_RAM_END);
 			size_t adjusted_sz = adjusted_end - adjusted_start;
 
diff --git a/kernel/pipe.c b/kernel/pipe.c
@@ -113,7 +113,7 @@ static size_t copy_to_pending_readers(struct k_pipe *pipe, bool *need_resched,
 			}
 
 			reader_buf = reader->base.swap_data;
-			copy_size = MIN(len - written,
+			copy_size = min(len - written,
 					reader_buf->len - reader_buf->used);
 			memcpy(&reader_buf->data[reader_buf->used],
 			       &data[written], copy_size);
diff --git a/kernel/sched.c b/kernel/sched.c
@@ -1005,7 +1005,7 @@ void z_impl_k_thread_absolute_deadline_set(k_tid_t tid, int deadline)
 void z_impl_k_thread_deadline_set(k_tid_t tid, int deadline)
 {
 
-	deadline = CLAMP(deadline, 0, INT_MAX);
+	deadline = clamp(deadline, 0, INT_MAX);
 
 	int32_t newdl = k_cycle_get_32() + deadline;
 
@@ -1139,7 +1139,7 @@ int32_t z_impl_k_sleep(k_timeout_t timeout)
 
 	/* k_sleep() still returns 32 bit milliseconds for compatibility */
 	int64_t ms = K_TIMEOUT_EQ(timeout, K_FOREVER) ? K_TICKS_FOREVER :
-		CLAMP(k_ticks_to_ms_ceil64(ticks), 0, INT_MAX);
+		clamp(k_ticks_to_ms_ceil64(ticks), 0, INT_MAX);
 
 	SYS_PORT_TRACING_FUNC_EXIT(k_thread, sleep, timeout, ms);
 	return (int32_t) ms;
diff --git a/kernel/thread.c b/kernel/thread.c
@@ -217,7 +217,7 @@ static size_t copy_bytes(char *dest, size_t dest_size, const char *src, size_t s
 {
 	size_t  bytes_to_copy;
 
-	bytes_to_copy = MIN(dest_size, src_size);
+	bytes_to_copy = min(dest_size, src_size);
 	memcpy(dest, src, bytes_to_copy);
 
 	return bytes_to_copy;
diff --git a/kernel/timeout.c b/kernel/timeout.c
@@ -90,7 +90,7 @@ static int32_t next_timeout(int32_t ticks_elapsed)
 	    ((int64_t)(to->dticks - ticks_elapsed) > (int64_t)INT_MAX)) {
 		ret = SYS_CLOCK_MAX_WAIT;
 	} else {
-		ret = MAX(0, to->dticks - ticks_elapsed);
+		ret = max(0, to->dticks - ticks_elapsed);
 	}
 
 	return ret;
@@ -124,7 +124,7 @@ k_ticks_t z_add_timeout(struct _timeout *to, _timeout_func_t fn, k_timeout_t tim
 		} else {
 			k_ticks_t dticks = Z_TICK_ABS(timeout.ticks) - curr_tick;
 
-			to->dticks = MAX(1, dticks);
+			to->dticks = max(1, dticks);
 			ticks = timeout.ticks;
 		}
 
@@ -322,7 +322,7 @@ k_timepoint_t sys_timepoint_calc(k_timeout_t timeout)
 		k_ticks_t dt = timeout.ticks;
 
 		if (Z_IS_TIMEOUT_RELATIVE(timeout)) {
-			timepoint.tick = sys_clock_tick_get() + MAX(1, dt);
+			timepoint.tick = sys_clock_tick_get() + max(1, dt);
 		} else {
 			timepoint.tick = Z_TICK_ABS(dt);
 		}
diff --git a/kernel/timer.c b/kernel/timer.c
@@ -57,7 +57,7 @@ void z_timer_expiration_handler(struct _timeout *t)
 		k_timeout_t next = timer->period;
 
 		/* see note about z_add_timeout() in z_impl_k_timer_start() */
-		next.ticks = MAX(next.ticks - 1, 0);
+		next.ticks = max(next.ticks - 1, 0);
 
 #ifdef CONFIG_TIMEOUT_64BIT
 		/* Exploit the fact that uptime during a kernel
@@ -171,7 +171,7 @@ void z_impl_k_timer_start(struct k_timer *timer, k_timeout_t duration,
 		 * is consistent for both 32-bit k_ticks_t which are unsigned
 		 * and 64-bit k_ticks_t which are signed.
 		 */
-		duration.ticks = MAX(1, duration.ticks);
+		duration.ticks = max(1, duration.ticks);
 		duration.ticks = duration.ticks - 1;
 	}
 
diff --git a/lib/heap/heap.c b/lib/heap/heap.c
@@ -17,7 +17,7 @@
 static inline void increase_allocated_bytes(struct z_heap *h, size_t num_bytes)
 {
 	h->allocated_bytes += num_bytes;
-	h->max_allocated_bytes = MAX(h->max_allocated_bytes, h->allocated_bytes);
+	h->max_allocated_bytes = max(h->max_allocated_bytes, h->allocated_bytes);
 }
 #endif
 
@@ -321,7 +321,7 @@ void *sys_heap_aligned_alloc(struct sys_heap *heap, size_t align, size_t bytes)
 	rew = align & -align;
 	if (align != rew) {
 		align -= rew;
-		gap = MIN(rew, chunk_header_bytes(h));
+		gap = min(rew, chunk_header_bytes(h));
 	} else {
 		if (align <= chunk_header_bytes(h)) {
 			return sys_heap_alloc(heap, bytes);
@@ -482,7 +482,7 @@ void *sys_heap_realloc(struct sys_heap *heap, void *ptr, size_t bytes)
 	if (ptr2 != NULL) {
 		size_t prev_size = sys_heap_usable_size(heap, ptr);
 
-		memcpy(ptr2, ptr, MIN(prev_size, bytes));
+		memcpy(ptr2, ptr, min(prev_size, bytes));
 		sys_heap_free(heap, ptr);
 	}
 	return ptr2;
@@ -516,7 +516,7 @@ void *sys_heap_aligned_realloc(struct sys_heap *heap, void *ptr,
 	if (ptr2 != NULL) {
 		size_t prev_size = sys_heap_usable_size(heap, ptr);
 
-		memcpy(ptr2, ptr, MIN(prev_size, bytes));
+		memcpy(ptr2, ptr, min(prev_size, bytes));
 		sys_heap_free(heap, ptr);
 	}
 	return ptr2;
diff --git a/lib/heap/heap.h b/lib/heap/heap.h
@@ -245,7 +245,7 @@ static ALWAYS_INLINE chunksz_t bytes_to_chunksz(struct z_heap *h, size_t bytes,
 	size_t oddments = ((bytes % CHUNK_UNIT) + (extra % CHUNK_UNIT) +
 			   chunk_header_bytes(h) + CHUNK_UNIT - 1U) / CHUNK_UNIT;
 
-	return (chunksz_t)MIN(chunks + oddments, h->end_chunk);
+	return (chunksz_t)min(chunks + oddments, h->end_chunk);
 }
 
 static inline chunksz_t min_chunk_size(struct z_heap *h)
diff --git a/lib/heap/heap_info.c b/lib/heap/heap_info.c
@@ -32,7 +32,7 @@ static void heap_print_info(struct z_heap *h, bool dump_chunks)
 
 			do {
 				count++;
-				largest = MAX(largest, chunk_size(h, curr));
+				largest = max(largest, chunk_size(h, curr));
 				curr = next_free_chunk(h, curr);
 			} while (curr != first);
 		}
diff --git a/lib/heap/multi_heap.c b/lib/heap/multi_heap.c
@@ -120,7 +120,7 @@ void *sys_multi_heap_aligned_realloc(struct sys_multi_heap *mheap, void *cfg,
 	/* Otherwise, allocate a new block and copy the data */
 	new_ptr = sys_multi_heap_aligned_alloc(mheap, cfg, align, bytes);
 	if (new_ptr != NULL) {
-		memcpy(new_ptr, ptr, MIN(old_size, bytes));
+		memcpy(new_ptr, ptr, min(old_size, bytes));
 		sys_multi_heap_free(mheap, ptr);
 	}
 
diff --git a/lib/libc/newlib/libc-hooks.c b/lib/libc/newlib/libc-hooks.c
@@ -121,7 +121,7 @@ static int malloc_prepare(void)
 
 #ifdef USE_MALLOC_PREPARE
 #ifdef CONFIG_MMU
-	max_heap_size = MIN(CONFIG_NEWLIB_LIBC_MAX_MAPPED_REGION_SIZE,
+	max_heap_size = min(CONFIG_NEWLIB_LIBC_MAX_MAPPED_REGION_SIZE,
 			    k_mem_free_get());
 
 	if (max_heap_size != 0) {
diff --git a/lib/net_buf/buf.c b/lib/net_buf/buf.c
@@ -354,7 +354,7 @@ struct net_buf *net_buf_alloc_len(struct net_buf_pool *pool, size_t size,
 #if defined(CONFIG_NET_BUF_POOL_USAGE)
 	atomic_dec(&pool->avail_count);
 	__ASSERT_NO_MSG(atomic_get(&pool->avail_count) >= 0);
-	pool->max_used = MAX(pool->max_used,
+	pool->max_used = max(pool->max_used,
 			     pool->buf_count - atomic_get(&pool->avail_count));
 #endif
 	return buf;
@@ -630,7 +630,7 @@ size_t net_buf_linearize(void *dst, size_t dst_len, const struct net_buf *src,
 	size_t to_copy;
 	size_t copied;
 
-	len = MIN(len, dst_len);
+	len = min(len, dst_len);
 
 	frag = src;
 
@@ -643,7 +643,7 @@ size_t net_buf_linearize(void *dst, size_t dst_len, const struct net_buf *src,
 	/* traverse the fragment chain until len bytes are copied */
 	copied = 0;
 	while (frag && len > 0) {
-		to_copy = MIN(len, frag->len - offset);
+		to_copy = min(len, frag->len - offset);
 		memcpy((uint8_t *)dst + copied, frag->data + offset, to_copy);
 
 		copied += to_copy;
@@ -673,7 +673,7 @@ size_t net_buf_append_bytes(struct net_buf *buf, size_t len,
 	size_t max_size;
 
 	do {
-		uint16_t count = MIN(len, net_buf_tailroom(frag));
+		uint16_t count = min(len, net_buf_tailroom(frag));
 
 		net_buf_add_mem(frag, value8, count);
 		len -= count;
@@ -695,7 +695,7 @@ size_t net_buf_append_bytes(struct net_buf *buf, size_t len,
 			pool = net_buf_pool_get(buf->pool_id);
 			max_size = pool->alloc->max_alloc_size;
 			frag = net_buf_alloc_len(pool,
-						 max_size ? MIN(len, max_size) : len,
+						 max_size ? min(len, max_size) : len,
 						 timeout);
 		}
 
@@ -729,7 +729,7 @@ size_t net_buf_data_match(const struct net_buf *buf, size_t offset, const void *
 
 	while (buf && len > 0) {
 		bptr = buf->data + offset;
-		to_compare = MIN(len, buf->len - offset);
+		to_compare = min(len, buf->len - offset);
 
 		for (size_t i = 0; i < to_compare; ++i) {
 			if (dptr[compared] != bptr[i]) {
diff --git a/lib/os/mpsc_pbuf.c b/lib/os/mpsc_pbuf.c
@@ -112,7 +112,7 @@ static inline void max_utilization_update(struct mpsc_pbuf_buffer *buffer)
 		return;
 	}
 
-	buffer->max_usage = MAX(buffer->max_usage, get_usage(buffer));
+	buffer->max_usage = max(buffer->max_usage, get_usage(buffer));
 }
 
 static inline bool is_valid(union mpsc_pbuf_generic *item)
diff --git a/lib/os/spsc_pbuf.c b/lib/os/spsc_pbuf.c
@@ -192,7 +192,7 @@ int spsc_pbuf_alloc(struct spsc_pbuf *pb, uint16_t len, char **buf)
 		free_space = rd_idx - wr_idx - FREE_SPACE_DISTANCE;
 	}
 
-	len = MIN(len, MAX(free_space - (int32_t)LEN_SZ, 0));
+	len = min(len, max(free_space - (int32_t)LEN_SZ, 0));
 	*buf = &data_loc[wr_idx + LEN_SZ];
 
 	return len;
diff --git a/lib/posix/options/file_system_r.c b/lib/posix/options/file_system_r.c
@@ -39,7 +39,7 @@ int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result)
 		return -rc;
 	}
 
-	strncpy(entry->d_name, de.name, MIN(sizeof(entry->d_name), sizeof(de.name)));
+	strncpy(entry->d_name, de.name, min(sizeof(entry->d_name), sizeof(de.name)));
 	entry->d_name[sizeof(entry->d_name) - 1] = '\0';
 
 	if (entry->d_name[0] == '\0') {
diff --git a/lib/posix/options/shm.c b/lib/posix/options/shm.c
@@ -211,7 +211,7 @@ static ssize_t shm_rw(struct shm_obj *shm, void *buf, size_t size, bool is_write
 	if (offset >= shm->size) {
 		size = 0;
 	} else {
-		size = MIN(size, shm->size - offset);
+		size = min(size, shm->size - offset);
 	}
 
 	if (size > 0) {
diff --git a/lib/posix/options/timespec_to_timeout.c b/lib/posix/options/timespec_to_timeout.c
@@ -21,5 +21,5 @@ uint32_t timespec_to_timeoutms(int clock_id, const struct timespec *abstime)
 		return 0;
 	}
 
-	return CLAMP(tp_diff(abstime, &curtime) / NSEC_PER_MSEC, 0, UINT32_MAX);
+	return clamp(tp_diff(abstime, &curtime) / NSEC_PER_MSEC, 0, UINT32_MAX);
 }
diff --git a/lib/utils/ring_buffer.c b/lib/utils/ring_buffer.c
@@ -20,7 +20,7 @@ uint32_t ring_buf_area_claim(struct ring_buf *buf, struct ring_buf_index *ring,
 		head_offset -= buf->size;
 	}
 	wrap_size = buf->size - head_offset;
-	size = MIN(size, wrap_size);
+	size = min(size, wrap_size);
 
 	*data = &buf->buffer[head_offset];
 	ring->head += size;
diff --git a/lib/utils/winstream.c b/lib/utils/winstream.c
@@ -55,7 +55,7 @@ void sys_winstream_write(struct sys_winstream *ws,
 	/* Make room in the buffer by advancing start first (note same
 	 * len-1 from above)
 	 */
-	len = MIN(len, ws->len);
+	len = min(len, ws->len);
 	if (seq != 0) {
 		uint32_t avail = (ws->len - 1) - idx_sub(ws, end, start);
 
@@ -71,7 +71,7 @@ void sys_winstream_write(struct sys_winstream *ws,
 		data += len0 - len;
 	}
 
-	suffix = MIN(len, ws->len - end);
+	suffix = min(len, ws->len - end);
 	MEMCPY(&ws->data[end], data, suffix);
 	if (len > suffix) {
 		MEMCPY(&ws->data[0], data + suffix, len - suffix);
@@ -109,8 +109,8 @@ uint32_t sys_winstream_read(struct sys_winstream *ws,
 
 		/* Copy data */
 		copy = idx_sub(ws, ws->end, behind);
-		len = MIN(buflen, behind);
-		suffix = MIN(len, ws->len - copy);
+		len = min(buflen, behind);
+		suffix = min(len, ws->len - copy);
 		MEMCPY(buf, &ws->data[copy], suffix);
 		if (len > suffix) {
 			MEMCPY(buf + suffix, &ws->data[0], len - suffix);

Original file line number	Diff line number	Diff line change
`@@ -113,7 +113,7 @@ static size_t copy_to_pending_readers(struct k_pipe pipe, bool need_resched,`
`113`	`113`	`}`
`114`	`114`
`115`	`115`	`reader_buf = reader->base.swap_data;`
`116`		`- copy_size = MIN(len - written,`
	`116`	`+ copy_size = min(len - written,`
`117`	`117`	`reader_buf->len - reader_buf->used);`
`118`	`118`	`memcpy(&reader_buf->data[reader_buf->used],`
`119`	`119`	`&data[written], copy_size);`
Original file line number	Diff line number	Diff line change
`@@ -217,7 +217,7 @@ static size_t copy_bytes(char dest, size_t dest_size, const char src, size_t s`
`217`	`217`	`{`
`218`	`218`	`size_t bytes_to_copy;`
`219`	`219`
`220`		`- bytes_to_copy = MIN(dest_size, src_size);`
	`220`	`+ bytes_to_copy = min(dest_size, src_size);`
`221`	`221`	`memcpy(dest, src, bytes_to_copy);`
`222`	`222`
`223`	`223`	`return bytes_to_copy;`
Original file line number	Diff line number	Diff line change
`@@ -245,7 +245,7 @@ static ALWAYS_INLINE chunksz_t bytes_to_chunksz(struct z_heap *h, size_t bytes,`
`245`	`245`	`size_t oddments = ((bytes % CHUNK_UNIT) + (extra % CHUNK_UNIT) +`
`246`	`246`	`chunk_header_bytes(h) + CHUNK_UNIT - 1U) / CHUNK_UNIT;`
`247`	`247`
`248`		`- return (chunksz_t)MIN(chunks + oddments, h->end_chunk);`
	`248`	`+ return (chunksz_t)min(chunks + oddments, h->end_chunk);`
`249`	`249`	`}`
`250`	`250`
`251`	`251`	`static inline chunksz_t min_chunk_size(struct z_heap *h)`