PM: hibernate: dynamically allocate crc->unc_len/unc for configurable threads

Convert crc->unc_len and crc->unc from fixed-size arrays to dynamically
allocated arrays, sized according to the actual number of threads selected
at runtime. This removes the fixed limit imposed by CMP_THREADS.

Signed-off-by: Xueqin Luo <luoxueqin@kylinos.cn>
Link: https://patch.msgid.link/b5db63bb95729482d2649b12d3a11cb7547b7fcc.1761046167.git.luoxueqin@kylinos.cn
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 0beff7eeaabaf82e37b7613a1e00f49b36f52976..f8c13f5672ec2289875468de2143d3bf954e089c 100644 (file)
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -585,10 +585,48 @@ struct crc_data {
        wait_queue_head_t go;                     /* start crc update */
        wait_queue_head_t done;                   /* crc update done */
        u32 *crc32;                               /* points to handle's crc32 */
-       size_t *unc_len[CMP_THREADS];             /* uncompressed lengths */
-       unsigned char *unc[CMP_THREADS];          /* uncompressed data */
+       size_t **unc_len;                         /* uncompressed lengths */
+       unsigned char **unc;                      /* uncompressed data */
 };
 
+static struct crc_data *alloc_crc_data(int nr_threads)
+{
+       struct crc_data *crc;
+
+       crc = kzalloc(sizeof(*crc), GFP_KERNEL);
+       if (!crc)
+               return NULL;
+
+       crc->unc = kcalloc(nr_threads, sizeof(*crc->unc), GFP_KERNEL);
+       if (!crc->unc)
+               goto err_free_crc;
+
+       crc->unc_len = kcalloc(nr_threads, sizeof(*crc->unc_len), GFP_KERNEL);
+       if (!crc->unc_len)
+               goto err_free_unc;
+
+       return crc;
+
+err_free_unc:
+       kfree(crc->unc);
+err_free_crc:
+       kfree(crc);
+       return NULL;
+}
+
+static void free_crc_data(struct crc_data *crc)
+{
+       if (!crc)
+               return;
+
+       if (crc->thr)
+               kthread_stop(crc->thr);
+
+       kfree(crc->unc_len);
+       kfree(crc->unc);
+       kfree(crc);
+}
+
 /*
  * CRC32 update function that runs in its own thread.
  */
@@ -719,7 +757,7 @@ static int save_compressed_image(struct swap_map_handle *handle,
                goto out_clean;
        }
 
-       crc = kzalloc(sizeof(*crc), GFP_KERNEL);
+       crc = alloc_crc_data(nr_threads);
        if (!crc) {
                pr_err("Failed to allocate crc\n");
                ret = -ENOMEM;
@@ -885,11 +923,7 @@ out_finish:
 
 out_clean:
        hib_finish_batch(&hb);
-       if (crc) {
-               if (crc->thr)
-                       kthread_stop(crc->thr);
-               kfree(crc);
-       }
+       free_crc_data(crc);
        if (data) {
                for (thr = 0; thr < nr_threads; thr++) {
                        if (data[thr].thr)
@@ -1239,7 +1273,7 @@ static int load_compressed_image(struct swap_map_handle *handle,
                goto out_clean;
        }
 
-       crc = kzalloc(sizeof(*crc), GFP_KERNEL);
+       crc = alloc_crc_data(nr_threads);
        if (!crc) {
                pr_err("Failed to allocate crc\n");
                ret = -ENOMEM;
@@ -1506,11 +1540,7 @@ out_clean:
        hib_finish_batch(&hb);
        for (i = 0; i < ring_size; i++)
                free_page((unsigned long)page[i]);
-       if (crc) {
-               if (crc->thr)
-                       kthread_stop(crc->thr);
-               kfree(crc);
-       }
+       free_crc_data(crc);
        if (data) {
                for (thr = 0; thr < nr_threads; thr++) {
                        if (data[thr].thr)