prov/util: Allow providers to update cache MR IOV

A provider may update the memory region that is added to accommodate for instance alignment of the region to a larger page boundary. In such cases, the MR cache info used to search the cache should use the updated region. This allows the provider to avoid walking /proc/pid/smaps if the underlying kernel component may more efficiently determine the backing page size. Signed-off-by: Steve Welch <[email protected]> Signed-off-by: Ian Ziemba <[email protected]>
pmodels · Oct 9, 2024 · df5472b · df5472b
1 parent 765cc16
commit df5472b
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Showing 2 changed files with 13 additions and 6 deletions.
diff --git a/include/ofi_mr.h b/include/ofi_mr.h
@@ -417,14 +417,15 @@ bool ofi_mr_cache_flush(struct ofi_mr_cache *cache, bool flush_lru);
  * a new ofi_mr_entry and assign it to entry.
  *
  * @param[in] cache     The cache the entry belongs to
- * @param[in] info      Information about the mr entry to search
+ * @param[in out] info  Information about the mr entry to search. Info IOV may
+ *			be updated by providers to reflect region registered by
+ *			the provider.
  * @param[out] entry    The registered entry corresponding to the
  *			region described in info.
  * @returns On success, returns 0. On failure, returns a negative error code.
  */
-int ofi_mr_cache_search(struct ofi_mr_cache *cache,
-			 const struct ofi_mr_info *info,
-			 struct ofi_mr_entry **entry);
+int ofi_mr_cache_search(struct ofi_mr_cache *cache, struct ofi_mr_info *info,
+			struct ofi_mr_entry **entry);
 
 /**
  * Given an attr (with an iov range), if the iov range is already registered,

diff --git a/prov/util/src/util_mr_cache.c b/prov/util/src/util_mr_cache.c
@@ -267,7 +267,7 @@ void ofi_mr_cache_delete(struct ofi_mr_cache *cache, struct ofi_mr_entry *entry)
  * restart the entire operation.
  */
 static int
-util_mr_cache_create(struct ofi_mr_cache *cache, const struct ofi_mr_info *info,
+util_mr_cache_create(struct ofi_mr_cache *cache, struct ofi_mr_info *info,
 		     struct ofi_mr_entry **entry)
 {
 	struct ofi_mr_entry *cur;
@@ -291,6 +291,12 @@ util_mr_cache_create(struct ofi_mr_cache *cache, const struct ofi_mr_info *info,
 	if (ret)
 		goto free;
 
+	/* Providers may have expanded the MR. Update MR info input
+	 * accordingly.
+	 */
+	assert(ofi_iov_within(&(*info).iov, &(*entry)->info.iov));
+	*info = (*entry)->info;
+
 	pthread_mutex_lock(&mm_lock);
 	cur = ofi_mr_rbt_find(&cache->tree, info);
 	if (cur) {
@@ -329,7 +335,7 @@ util_mr_cache_create(struct ofi_mr_cache *cache, const struct ofi_mr_info *info,
 	return ret;
 }
 
-int ofi_mr_cache_search(struct ofi_mr_cache *cache, const struct ofi_mr_info *info,
+int ofi_mr_cache_search(struct ofi_mr_cache *cache, struct ofi_mr_info *info,
 			struct ofi_mr_entry **entry)
 {
 	struct ofi_mem_monitor *monitor;