vppinfra: refactor interrupt code

Type: improvement
Change-Id: Ie6987736faf7d8a641762e276775da8ee0c03ea4
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 39 insertions, 59 deletions

diff --git a/src/vppinfra/interrupt.c b/src/vppinfra/interrupt.c
index df242d932b6..c9f0078c5e4 100644
--- a/src/vppinfra/interrupt.c
+++ b/src/vppinfra/interrupt.c
@@ -1,42 +1,33 @@
-
-/*
- * Copyright (c) 2020 Cisco and/or its affiliates.
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at:
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/* SPDX-License-Identifier: Apache-2.0
+ * Copyright (c) 2023 Cisco Systems, Inc.
  */
 
 #include <vppinfra/clib.h>
-#include <vppinfra/vec.h>
 #include <vppinfra/interrupt.h>
-#include <vppinfra/format.h>
 
 __clib_export void
-clib_interrupt_init (void **data, uword n_int)
+clib_interrupt_init (void **data, u32 n_int)
 {
   clib_interrupt_header_t *h;
-  uword sz = sizeof (clib_interrupt_header_t);
-  uword data_size = round_pow2 (n_int, CLIB_CACHE_LINE_BYTES * 8) / 8;
+  const u32 bits_in_cl = 8 << CLIB_LOG2_CACHE_LINE_BYTES;
+  u32 sz = sizeof (clib_interrupt_header_t);
+  u32 n_cl = round_pow2 (n_int, bits_in_cl) / bits_in_cl;
 
-  sz += 2 * data_size;
+  sz += 2 * n_cl * CLIB_CACHE_LINE_BYTES;
   h = data[0] = clib_mem_alloc_aligned (sz, CLIB_CACHE_LINE_BYTES);
   clib_memset (data[0], 0, sz);
   h->n_int = n_int;
-  h->n_uword_alloc = (data_size * 8) >> log2_uword_bits;
+  h->uwords_allocated = n_cl * bits_in_cl / uword_bits;
+  h->uwords_used = round_pow2 (n_int, uword_bits) / uword_bits;
+  h->local = (uword *) (h + 1);
+  h->remote = h->local + h->uwords_allocated;
 }
 
 __clib_export void
-clib_interrupt_resize (void **data, uword n_int)
+clib_interrupt_resize (void **data, u32 n_int)
 {
   clib_interrupt_header_t *h = data[0];
+  u32 new_n_uwords, i;
 
   if (data[0] == 0)
     {
@@ -44,48 +35,37 @@ clib_interrupt_resize (void **data, uword n_int)
       return;
     }
 
-  if (n_int < h->n_int)
+  if (n_int == h->n_int)
+    return;
+
+  new_n_uwords = round_pow2 (n_int, uword_bits) / uword_bits;
+
+  if (new_n_uwords > h->uwords_allocated)
     {
-      uword *old_bmp, *old_abp, v;
-      old_bmp = clib_interrupt_get_bitmap (data[0]);
-      old_abp = clib_interrupt_get_atomic_bitmap (data[0]);
-      for (uword i = 0; i < h->n_uword_alloc; i++)
-	{
-	  v = old_abp[i];
-	  old_abp[i] = 0;
-	  if (n_int > ((i + 1) * uword_bits))
-	    old_bmp[i] |= v;
-	  else if (n_int > (i * uword_bits))
-	    old_bmp[i] = (old_bmp[i] | v) & pow2_mask (n_int - i * uword_bits);
-	  else
-	    old_bmp[i] = 0;
-	}
+      clib_interrupt_header_t *nh;
+      clib_interrupt_init ((void **) &nh, n_int);
+      for (int i = 0; i < h->uwords_used; i++)
+	nh->local[i] = h->local[i] | h->remote[i];
+      clib_mem_free (data[0]);
+      data[0] = nh;
+      return;
     }
-  else if (n_int > h->n_uword_alloc * uword_bits)
-    {
-      void *old = data[0];
-      uword *old_bmp, *old_abp, *new_bmp;
-      uword n_uwords = round_pow2 (h->n_int, uword_bits) / uword_bits;
 
-      clib_interrupt_init (data, n_int);
-      h = data[0];
+  h->n_int = n_int;
+  h->uwords_used = new_n_uwords;
 
-      new_bmp = clib_interrupt_get_bitmap (data[0]);
-      old_bmp = clib_interrupt_get_bitmap (old);
-      old_abp = clib_interrupt_get_atomic_bitmap (old);
+  for (i = 0; i < new_n_uwords; i++)
+    h->local[i] |= h->remote[i];
 
-      for (uword i = 0; i < n_uwords; i++)
-	new_bmp[i] = old_bmp[i] | old_abp[i];
+  for (i = 0; i < h->uwords_allocated; i++)
+    h->remote[i] = 0;
 
-      clib_mem_free (old);
-    }
-  h->n_int = n_int;
+  for (i = new_n_uwords; i < h->uwords_allocated; i++)
+    h->local[i] = 0;
+
+  n_int &= pow2_mask (log2_uword_bits);
+
+  if (n_int)
+    h->local[n_int >> log2_uword_bits] &= pow2_mask (n_int);
 }
 
-/*
- * fd.io coding-style-patch-verification: ON
- *
- * Local Variables:
- * eval: (c-set-style "gnu")
- * End:
- */