Use swap()

[GustavoARSilva]

If you send a proper patch for this CC me: Gustavo A. R. Silva <[email protected]>

linux-next-20220104$ time make coccicheck -j 128 COCCI=scripts/coccinelle/misc/swap.cocci MODE=patch 2>&1 | tee swap.patch

some examples:

diff -u -p a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c
--- a/kernel/locking/test-ww_mutex.c
+++ b/kernel/locking/test-ww_mutex.c
@@ -400,11 +400,8 @@ static int *get_random_order(int count)

        for (n = count - 1; n > 1; n--) {
                r = get_random_int() % (n + 1);
-               if (r != n) {
-                       tmp = order[n];
-                       order[n] = order[r];
-                       order[r] = tmp;
-               }
+               if (r != n)
+                       swap(order[n], order[r]);
        }

        return order;
diff -u -p a/drivers/net/ethernet/sfc/efx_channels.c b/drivers/net/ethernet/sfc/efx_channels.c
--- a/drivers/net/ethernet/sfc/efx_channels.c
+++ b/drivers/net/ethernet/sfc/efx_channels.c
@@ -819,11 +819,8 @@ int efx_realloc_channels(struct efx_nic
        old_txq_entries = efx->txq_entries;
        efx->rxq_entries = rxq_entries;
        efx->txq_entries = txq_entries;
-       for (i = 0; i < efx->n_channels; i++) {
-               channel = efx->channel[i];
-               efx->channel[i] = other_channel[i];
-               other_channel[i] = channel;
-       }
+       for (i = 0; i < efx->n_channels; i++)
+               swap(efx->channel[i], other_channel[i]);

        /* Restart buffer table allocation */
        efx->next_buffer_table = next_buffer_table;
@@ -865,11 +862,8 @@ rollback:
        /* Swap back */
        efx->rxq_entries = old_rxq_entries;
        efx->txq_entries = old_txq_entries;
-       for (i = 0; i < efx->n_channels; i++) {
-               channel = efx->channel[i];
-               efx->channel[i] = other_channel[i];
-               other_channel[i] = channel;
-       }
+       for (i = 0; i < efx->n_channels; i++)
+               swap(efx->channel[i], other_channel[i]);
        goto out;
 }

diff -u -p a/fs/ntfs3/lib/lzx_decompress.c b/fs/ntfs3/lib/lzx_decompress.c
--- a/fs/ntfs3/lib/lzx_decompress.c
+++ b/fs/ntfs3/lib/lzx_decompress.c
@@ -511,9 +511,7 @@ static int lzx_decompress_block(const st
                         * quirk allows all 3 recent offsets to be handled by
                         * the same code.  (For R0, the swap is a no-op.)
                         */
-                       match_offset = recent_offsets[offset_slot];
-                       recent_offsets[offset_slot] = recent_offsets[0];
-                       recent_offsets[0] = match_offset;
+                       swap(recent_offsets[offset_slot], recent_offsets[0]);
                } else {
                        /* Explicit offset  */

diff -u -p a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -196,7 +196,6 @@ static struct orc_entry *cur_orc_table =
 static void orc_sort_swap(void *_a, void *_b, int size)
 {
        struct orc_entry *orc_a, *orc_b;
-       struct orc_entry orc_tmp;
        int *a = _a, *b = _b, tmp;
        int delta = _b - _a;

@@ -208,9 +207,7 @@ static void orc_sort_swap(void *_a, void
        /* Swap the corresponding .orc_unwind entries: */
        orc_a = cur_orc_table + (a - cur_orc_ip_table);
        orc_b = cur_orc_table + (b - cur_orc_ip_table);
-       orc_tmp = *orc_a;
-       *orc_a = *orc_b;
-       *orc_b = orc_tmp;
+       swap(*orc_a, *orc_b);
 }

 static int orc_sort_cmp(const void *_a, const void *_b)
diff -u -p a/tools/testing/radix-tree/main.c b/tools/testing/radix-tree/main.c
--- a/tools/testing/radix-tree/main.c
+++ b/tools/testing/radix-tree/main.c
@@ -163,11 +163,8 @@ void copy_tag_check(void)
 //     printf("generating radix tree indices...\n");
        start = rand();
        end = rand();
-       if (start > end && (rand() % 10)) {
-               cur = start;
-               start = end;
-               end = cur;
-       }
+       if (start > end && (rand() % 10))
+               swap(start, end);
        /* Specifically create items around the start and the end of the range
         * with high probability to check for off by one errors */
        cur = rand();