Currently, in the case when we search for a bit set after a particular
value, the bitmap has to be scanned from the beginning and
rte_bitmap_scan() has to be called multiple times until we hit the value.
Add a new __rte_bitmap_scan_init_at() function to initialize scan state at
the given position, this will allow getting the next bit set after some
value within one rte_bitmap_scan() call.
Signed-off-by: Volodymyr Fialko <vfia...@marvell.com>
---
app/test/test_bitmap.c | 23 +++++++++++++++++++++++
lib/eal/include/rte_bitmap.h | 22 ++++++++++++++++++++++
2 files changed, 45 insertions(+)
diff --git a/app/test/test_bitmap.c b/app/test/test_bitmap.c
index e9c61590ae..69ff7262f3 100644
--- a/app/test/test_bitmap.c
+++ b/app/test/test_bitmap.c
@@ -71,6 +71,29 @@ test_bitmap_scan_operations(struct rte_bitmap *bmp)
return TEST_FAILED;
}
+ /* Scan reset with count check. */
+ __rte_bitmap_scan_init_at(bmp, pos + RTE_BITMAP_SLAB_BIT_SIZE);
+ if (!rte_bitmap_scan(bmp, &pos, &out_slab)) {
+ printf("Failed to get slab from bitmap.\n");
+ return TEST_FAILED;
+ }
+
+ if (slab2_magic != out_slab) {
+ printf("Scan init at operation failed.\n");
+ return TEST_FAILED;
+ }
+
+ __rte_bitmap_scan_init_at(bmp, pos + 2 * RTE_BITMAP_SLAB_BIT_SIZE);
+ if (!rte_bitmap_scan(bmp, &pos, &out_slab)) {
+ printf("Failed to get slab from bitmap.\n");
+ return TEST_FAILED;
+ }
+
+ if (slab1_magic != out_slab) {
+ printf("Scan init at operation failed.\n");
+ return TEST_FAILED;
+ }
+
/* Test scan when a cline is half full */
rte_bitmap_reset(bmp);
for (i = 0; i < MAX_BITS; i++)
diff --git a/lib/eal/include/rte_bitmap.h b/lib/eal/include/rte_bitmap.h
index 27ee3d18a4..54a986aa8f 100644
--- a/lib/eal/include/rte_bitmap.h
+++ b/lib/eal/include/rte_bitmap.h
@@ -137,6 +137,28 @@ __rte_bitmap_scan_init(struct rte_bitmap *bmp)
bmp->go2 = 0;
}
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Bitmap initialize internal scan pointers at the given position for the scan
function.
+ * @see rte_bitmap_scan()
+ *
+ * @param bmp
+ * Handle to bitmap instance
+ * @param pos
+ * Bit position to start scan
+ */
+__rte_experimental
+static inline void
+__rte_bitmap_scan_init_at(struct rte_bitmap *bmp, uint32_t pos)
+{
+ bmp->index1 = pos >> (RTE_BITMAP_SLAB_BIT_SIZE_LOG2 +
RTE_BITMAP_CL_BIT_SIZE_LOG2);
+ bmp->offset1 = (pos >> RTE_BITMAP_CL_BIT_SIZE_LOG2) &
RTE_BITMAP_SLAB_BIT_MASK;
+ bmp->index2 = pos >> RTE_BITMAP_SLAB_BIT_SIZE_LOG2;
+ bmp->go2 = 1;
+}
+
/**
* Bitmap memory footprint calculation
*
--
2.34.1
