Signed-off-by: Waldemar Kozaczuk <jwkozac...@gmail.com>
---
 .../lib/libzfs/common/libzfs_import.c         | 48 +++++++++++++++++--
 1 file changed, 43 insertions(+), 5 deletions(-)

diff --git a/bsd/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c 
b/bsd/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
index 1f8fe36f..908d4b4d 100644
--- a/bsd/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
+++ b/bsd/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
@@ -1127,6 +1127,7 @@ zpool_clear_label(int fd)
  * poolname or guid (but not both) are provided by the caller when trying
  * to import a specific pool.
  */
+#define MAX_MOUNTED_DEVS 64
 static nvlist_t *
 zpool_find_import_impl(libzfs_handle_t *hdl, importargs_t *iarg)
 {
@@ -1146,6 +1147,8 @@ zpool_find_import_impl(libzfs_handle_t *hdl, importargs_t 
*iarg)
        avl_tree_t slice_cache;
        rdsk_node_t *slice;
        void *cookie;
+       char *excluded_dev_names[MAX_MOUNTED_DEVS];
+       int excluded_dev_count = 0;
 
        if (dirs == 0) {
                dirs = 1;
@@ -1229,6 +1232,28 @@ zpool_find_import_impl(libzfs_handle_t *hdl, 
importargs_t *iarg)
                }
 #endif
 
+#ifdef __OSV__
+               // Iterate over all mounts and identify the devices we wanted 
to exlude
+               FILE *ent = fopen("/etc/fstab", "r");
+               if (ent) {
+                       struct mnttab m;
+                       while (getmntent(ent, &m) == 0) {
+                               if (strcmp("none", m.mnt_special) == 0) {
+                                       continue;
+                               }
+                               char *dev_name = 
excluded_dev_names[excluded_dev_count++] = strdup(m.mnt_special + 5);
+                               // If the device has a '.' in it it means it 
corresponds to a disk partion
+                               // and in this case we should skip the parent 
disk as well as it will make
+                               // the pool discovery slow. For example for 
'vblk0.1' exclude 'vblk0' as well but
+                               // not 'vblk0.2'
+                               char *dot_pos = strchr(dev_name, '.');
+                               if (dot_pos) {
+                                       
excluded_dev_names[excluded_dev_count++] = strndup(dev_name, dot_pos - 
dev_name);
+                               }
+                       }
+                       fclose(ent);
+               }
+#endif
                /*
                 * This is not MT-safe, but we have no MT consumers of libzfs
                 */
@@ -1238,12 +1263,20 @@ zpool_find_import_impl(libzfs_handle_t *hdl, 
importargs_t *iarg)
                            (name[1] == 0 || (name[1] == '.' && name[2] == 0)))
                                continue;
 #ifdef __OSV__
-                       /* In OSv, mount_zfs_roofs() always mounts /dev/vblk0.1
-                        * before calling zpool import, so this device is
-                        * already mounted, and trying to do it again while
-                        * it is already mounted is surprisingly slow.
+                       /* Trying to call zpool import on a device that we
+                        * have already mounted ZFS root pool from before,
+                        * is surprisingly slow. So let us try to avoid it
+                        * by filtering it out using a list of mounted devices
+                        * identified before in excluded_dev_names.
                         */
-                       if (!strcmp(name, "vblk0.1"))
+                       bool skip_entry = false;
+                       for (int i = 0; i < excluded_dev_count; i++) {
+                               if (!strcmp(name, excluded_dev_names[i])) {
+                                       skip_entry = true;
+                                       break;
+                               }
+                       }
+                       if (skip_entry)
                                continue;
 #endif
 
@@ -1255,6 +1288,11 @@ zpool_find_import_impl(libzfs_handle_t *hdl, 
importargs_t *iarg)
                        slice->rn_nozpool = B_FALSE;
                        avl_add(&slice_cache, slice);
                }
+#ifdef __OSV__
+               while (excluded_dev_count) {
+                       free(excluded_dev_names[--excluded_dev_count]);
+               }
+#endif
 
 #ifndef __OSV__
 skipdir:
-- 
2.35.1

-- 
You received this message because you are subscribed to the Google Groups "OSv 
Development" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to osv-dev+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/osv-dev/20220717053624.96106-1-jwkozaczuk%40gmail.com.

Reply via email to