Currently, while there is a way to find total amount of used/free
space in an fbarray, there is no way to find biggest contiguous
chunk. Add such API, as well as unit tests to test this API.
Signed-off-by: Anatoly Burakov <anatoly.bura...@intel.com>
---
lib/librte_eal/common/eal_common_fbarray.c | 109 ++++++++++++++
lib/librte_eal/common/include/rte_fbarray.h | 70 +++++++++
lib/librte_eal/rte_eal_version.map | 4 +
test/test/test_fbarray.c | 159 ++++++++++++++++++++
4 files changed, 342 insertions(+)
diff --git a/lib/librte_eal/common/eal_common_fbarray.c
b/lib/librte_eal/common/eal_common_fbarray.c
index ea0735cb8..5665282cd 100644
--- a/lib/librte_eal/common/eal_common_fbarray.c
+++ b/lib/librte_eal/common/eal_common_fbarray.c
@@ -1162,6 +1162,115 @@ fbarray_find_contig(struct rte_fbarray *arr, unsigned
int start, bool next,
return ret;
}
+static int
+fbarray_find_biggest(struct rte_fbarray *arr, unsigned int start, bool used,
+ bool rev)
+{
+ int cur_idx, next_idx, cur_len, biggest_idx, biggest_len;
+ /* don't stack if conditions, use function pointers instead */
+ int (*find_func)(struct rte_fbarray *, unsigned int);
+ int (*find_contig_func)(struct rte_fbarray *, unsigned int);
+
+ if (arr == NULL || start >= arr->len) {
+ rte_errno = EINVAL;
+ return -1;
+ }
+ /* the other API calls already do their fair share of cheap checks, so
+ * no need to do them here.
+ */
+
+ /* the API's called are thread-safe, but something may still happen
+ * inbetween the API calls, so lock the fbarray. all other API's are
+ * read-locking the fbarray, so read lock here is OK.
+ */
+ rte_rwlock_read_lock(&arr->rwlock);
+
+ /* pick out appropriate functions */
+ if (used) {
+ if (rev) {
+ find_func = rte_fbarray_find_prev_used;
+ find_contig_func = rte_fbarray_find_rev_contig_used;
+ } else {
+ find_func = rte_fbarray_find_next_used;
+ find_contig_func = rte_fbarray_find_contig_used;
+ }
+ } else {
+ if (rev) {
+ find_func = rte_fbarray_find_prev_free;
+ find_contig_func = rte_fbarray_find_rev_contig_free;
+ } else {
+ find_func = rte_fbarray_find_next_free;
+ find_contig_func = rte_fbarray_find_contig_free;
+ }
+ }
+
+ cur_idx = start;
+ biggest_idx = -1; /* default is error */
+ biggest_len = 0;
+ for (;;) {
+ cur_idx = find_func(arr, cur_idx);
+
+ /* block found, check its length */
+ if (cur_idx >= 0) {
+ cur_len = find_contig_func(arr, cur_idx);
+ /* decide where we go next */
+ next_idx = rev ? cur_idx - cur_len : cur_idx + cur_len;
+ /* move current index to start of chunk */
+ cur_idx = rev ? next_idx + 1 : cur_idx;
+
+ if (cur_len > biggest_len) {
+ biggest_idx = cur_idx;
+ biggest_len = cur_len;
+ }
+ cur_idx = next_idx;
+ /* in reverse mode, next_idx may be -1 if chunk started
+ * at array beginning. this means there's no more work
+ * to do.
+ */
+ if (cur_idx < 0)
+ break;
+ } else {
+ /* nothing more to find, stop. however, a failed API
+ * call has set rte_errno, which we want to ignore, as
+ * reaching the end of fbarray is not an error.
+ */
+ rte_errno = 0;
+ break;
+ }
+ }
+ /* if we didn't find anything at all, set rte_errno */
+ if (biggest_idx < 0)
+ rte_errno = used ? ENOENT : ENOSPC;
+
+ rte_rwlock_read_unlock(&arr->rwlock);
+ return biggest_idx;
+}
+
+int __rte_experimental
+rte_fbarray_find_biggest_free(struct rte_fbarray *arr, unsigned int start)
+{
+ return fbarray_find_biggest(arr, start, false, false);
+}
+
+int __rte_experimental
+rte_fbarray_find_biggest_used(struct rte_fbarray *arr, unsigned int start)
+{
+ return fbarray_find_biggest(arr, start, true, false);
+}
+
+int __rte_experimental
+rte_fbarray_find_rev_biggest_free(struct rte_fbarray *arr, unsigned int start)
+{
+ return fbarray_find_biggest(arr, start, false, true);
+}
+
+int __rte_experimental
+rte_fbarray_find_rev_biggest_used(struct rte_fbarray *arr, unsigned int start)
+{
+ return fbarray_find_biggest(arr, start, true, true);
+}
+
+
int __rte_experimental
rte_fbarray_find_contig_free(struct rte_fbarray *arr, unsigned int start)
{
diff --git a/lib/librte_eal/common/include/rte_fbarray.h
b/lib/librte_eal/common/include/rte_fbarray.h
index 5d8805515..33841ca9a 100644
--- a/lib/librte_eal/common/include/rte_fbarray.h
+++ b/lib/librte_eal/common/include/rte_fbarray.h
@@ -451,6 +451,76 @@ int __rte_experimental
rte_fbarray_find_rev_contig_used(struct rte_fbarray *arr, unsigned int start);
+/**
+ * Find index of biggest chunk of free elements, starting at specified index.
+ *
+ * @param arr
+ * Valid pointer to allocated and correctly set up ``rte_fbarray`` structure.
+ *
+ * @param start
+ * Element index to start search from.
+ *
+ * @return
+ * - non-negative integer on success.
+ * - -1 on failure, with ``rte_errno`` indicating reason for failure.
+ */
+int __rte_experimental
+rte_fbarray_find_biggest_free(struct rte_fbarray *arr, unsigned int start);
+
+
+/**
+ * Find index of biggest chunk of used elements, starting at specified index.
+ *
+ * @param arr
+ * Valid pointer to allocated and correctly set up ``rte_fbarray`` structure.
+ *
+ * @param start
+ * Element index to start search from.
+ *
+ * @return
+ * - non-negative integer on success.
+ * - -1 on failure, with ``rte_errno`` indicating reason for failure.
+ */
+int __rte_experimental
+rte_fbarray_find_biggest_used(struct rte_fbarray *arr, unsigned int start);
+
+
+/**
+ * Find index of biggest chunk of free elements before a specified index (like
+ * ``rte_fbarray_find_biggest_free``, but going in reverse).
+ *
+ * @param arr
+ * Valid pointer to allocated and correctly set up ``rte_fbarray`` structure.
+ *
+ * @param start
+ * Element index to start search from.
+ *
+ * @return
+ * - non-negative integer on success.
+ * - -1 on failure, with ``rte_errno`` indicating reason for failure.
+ */
+int __rte_experimental
+rte_fbarray_find_rev_biggest_free(struct rte_fbarray *arr, unsigned int start);
+
+
+/**
+ * Find index of biggest chunk of used elements before a specified index (like
+ * ``rte_fbarray_find_biggest_used``, but going in reverse).
+ *
+ * @param arr
+ * Valid pointer to allocated and correctly set up ``rte_fbarray`` structure.
+ *
+ * @param start
+ * Element index to start search from.
+ *
+ * @return
+ * - non-negative integer on success.
+ * - -1 on failure, with ``rte_errno`` indicating reason for failure.
+ */
+int __rte_experimental
+rte_fbarray_find_rev_biggest_used(struct rte_fbarray *arr, unsigned int start);
+
+
/**
* Dump ``rte_fbarray`` metadata.
*
diff --git a/lib/librte_eal/rte_eal_version.map
b/lib/librte_eal/rte_eal_version.map
index eb5f7b9cb..d78deaa8a 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -305,6 +305,8 @@ EXPERIMENTAL {
rte_fbarray_detach;
rte_fbarray_dump_metadata;
rte_fbarray_find_idx;
+ rte_fbarray_find_biggest_free;
+ rte_fbarray_find_biggest_used;
rte_fbarray_find_next_free;
rte_fbarray_find_next_used;
rte_fbarray_find_next_n_free;
@@ -315,6 +317,8 @@ EXPERIMENTAL {
rte_fbarray_find_prev_n_used;
rte_fbarray_find_contig_free;
rte_fbarray_find_contig_used;
+ rte_fbarray_find_rev_biggest_free;
+ rte_fbarray_find_rev_biggest_used;
rte_fbarray_find_rev_contig_free;
rte_fbarray_find_rev_contig_used;
rte_fbarray_get;
diff --git a/test/test/test_fbarray.c b/test/test/test_fbarray.c
index 8c44e2c7e..d2b041887 100644
--- a/test/test/test_fbarray.c
+++ b/test/test/test_fbarray.c
@@ -97,6 +97,8 @@ static int empty_msk_test_setup(void)
{
/* do not fill anything in */
reset_array();
+ param.start = -1;
+ param.end = -1;
return 0;
}
@@ -456,6 +458,157 @@ static int test_basic(void)
return TEST_SUCCESS;
}
+static int test_biggest(struct rte_fbarray *arr, int first, int last)
+{
+ int lo_free_space_first, lo_free_space_last, lo_free_space_len;
+ int hi_free_space_first, hi_free_space_last, hi_free_space_len;
+ int max_free_space_first, max_free_space_last, max_free_space_len;
+ int len = last - first + 1;
+
+ /* first and last must either be both -1, or both not -1 */
+ TEST_ASSERT((first == -1) == (last == -1),
+ "Invalid arguments provided\n");
+
+ /* figure out what we expect from the low chunk of free space */
+ if (first == -1) {
+ /* special case: if there are no occupied elements at all,
+ * consider both free spaces to consume the entire array.
+ */
+ lo_free_space_first = 0;
+ lo_free_space_last = arr->len - 1;
+ lo_free_space_len = arr->len;
+ /* if there's no used space, length should be invalid */
+ len = -1;
+ } else if (first == 0) {
+ /* if occupied items start at 0, there's no free space */
+ lo_free_space_first = -1;
+ lo_free_space_last = -1;
+ lo_free_space_len = 0;
+ } else {
+ lo_free_space_first = 0;
+ lo_free_space_last = first - 1;
+ lo_free_space_len = lo_free_space_last -
+ lo_free_space_first + 1;
+ }
+
+ /* figure out what we expect from the high chunk of free space */
+ if (last == -1) {
+ /* special case: if there are no occupied elements at all,
+ * consider both free spaces to consume the entire array.
+ */
+ hi_free_space_first = 0;
+ hi_free_space_last = arr->len - 1;
+ hi_free_space_len = arr->len;
+ /* if there's no used space, length should be invalid */
+ len = -1;
+ } else if (last == ((int)arr->len - 1)) {
+ /* if occupied items end at array len, there's no free space */
+ hi_free_space_first = -1;
+ hi_free_space_last = -1;
+ hi_free_space_len = 0;
+ } else {
+ hi_free_space_first = last + 1;
+ hi_free_space_last = arr->len - 1;
+ hi_free_space_len = hi_free_space_last -
+ hi_free_space_first + 1;
+ }
+
+ /* find which one will be biggest */
+ if (lo_free_space_len > hi_free_space_len) {
+ max_free_space_first = lo_free_space_first;
+ max_free_space_last = lo_free_space_last;
+ max_free_space_len = lo_free_space_len;
+ } else {
+ /* if they are equal, we'll just use the high chunk */
+ max_free_space_first = hi_free_space_first;
+ max_free_space_last = hi_free_space_last;
+ max_free_space_len = hi_free_space_len;
+ }
+
+ /* check used regions - these should produce identical results */
+ TEST_ASSERT_EQUAL(rte_fbarray_find_biggest_used(arr, 0), first,
+ "Used space index is wrong\n");
+ TEST_ASSERT_EQUAL(rte_fbarray_find_rev_biggest_used(arr, arr->len - 1),
+ first,
+ "Used space index is wrong\n");
+ /* len may be -1, but function will return error anyway */
+ TEST_ASSERT_EQUAL(rte_fbarray_find_contig_used(arr, first), len,
+ "Used space length is wrong\n");
+
+ /* check if biggest free region is the one we expect to find. It can be
+ * -1 if there's no free space - we've made sure we use one or the
+ * other, even if both are invalid.
+ */
+ TEST_ASSERT_EQUAL(rte_fbarray_find_biggest_free(arr, 0),
+ max_free_space_first,
+ "Biggest free space index is wrong\n");
+ TEST_ASSERT_EQUAL(rte_fbarray_find_rev_biggest_free(arr, arr->len - 1),
+ max_free_space_first,
+ "Biggest free space index is wrong\n");
+
+ /* if biggest region exists, check its length */
+ if (max_free_space_first != -1) {
+ TEST_ASSERT_EQUAL(rte_fbarray_find_contig_free(arr,
+ max_free_space_first),
+ max_free_space_len,
+ "Biggest free space length is wrong\n");
+ TEST_ASSERT_EQUAL(rte_fbarray_find_rev_contig_free(arr,
+ max_free_space_last),
+ max_free_space_len,
+ "Biggest free space length is wrong\n");
+ }
+
+ /* find if we see what we expect to see in the low region. if there is
+ * no free space, the function should still match expected value, as
+ * we've set it to -1. we're scanning backwards to avoid accidentally
+ * hitting the high free space region. if there is no occupied space,
+ * there's nothing to do.
+ */
+ if (last != -1) {
+ TEST_ASSERT_EQUAL(rte_fbarray_find_rev_biggest_free(arr, last),
+ lo_free_space_first,
+ "Low free space index is wrong\n");
+ }
+
+ if (lo_free_space_first != -1) {
+ /* if low free region exists, check its length */
+ TEST_ASSERT_EQUAL(rte_fbarray_find_contig_free(arr,
+ lo_free_space_first),
+ lo_free_space_len,
+ "Low free space length is wrong\n");
+ TEST_ASSERT_EQUAL(rte_fbarray_find_rev_contig_free(arr,
+ lo_free_space_last),
+ lo_free_space_len,
+ "Low free space length is wrong\n");
+ }
+
+ /* find if we see what we expect to see in the high region. if there is
+ * no free space, the function should still match expected value, as
+ * we've set it to -1. we're scanning forwards to avoid accidentally
+ * hitting the low free space region. if there is no occupied space,
+ * there's nothing to do.
+ */
+ if (first != -1) {
+ TEST_ASSERT_EQUAL(rte_fbarray_find_biggest_free(arr, first),
+ hi_free_space_first,
+ "High free space index is wrong\n");
+ }
+
+ /* if high free region exists, check its length */
+ if (hi_free_space_first != -1) {
+ TEST_ASSERT_EQUAL(rte_fbarray_find_contig_free(arr,
+ hi_free_space_first),
+ hi_free_space_len,
+ "High free space length is wrong\n");
+ TEST_ASSERT_EQUAL(rte_fbarray_find_rev_contig_free(arr,
+ hi_free_space_last),
+ hi_free_space_len,
+ "High free space length is wrong\n");
+ }
+
+ return 0;
+}
+
static int ensure_correct(struct rte_fbarray *arr, int first, int last,
bool used)
{
@@ -537,6 +690,9 @@ static int test_find(void)
if (ensure_correct(¶m.arr, param.end + 1, FBARRAY_TEST_LEN - 1,
false))
return TEST_FAILED;
+ /* test if find_biggest API's work correctly */
+ if (test_biggest(¶m.arr, param.start, param.end))
+ return TEST_FAILED;
return TEST_SUCCESS;
}
@@ -546,6 +702,9 @@ static int test_empty(void)
/* ensure space is free */
if (ensure_correct(¶m.arr, 0, FBARRAY_TEST_LEN - 1, false))
return TEST_FAILED;
+ /* test if find_biggest API's work correctly */
+ if (test_biggest(¶m.arr, param.start, param.end))
+ return TEST_FAILED;
return TEST_SUCCESS;
}
--
2.17.1
