CORTX-33537: disable alternative pvers by default

We want the I/O to be done in the base pool version in the
degraded mode. Later, when we introduce the side pool versions,
we will do the degraded I/O in them and use them for fasters
SNS-recovery, which will try to recover only the objects which
have the side pool versions instead of traversing all objects
in the cluster.

Closes Seagate#1958.

Signed-off-by: Andriy Tkachuk <andriy.tkachuk@seagate.com>

conf/pvers.c

@@ -145,13 +145,17 @@ static int conf_pver_find_locked(const struct m0_conf_pool *pool,
 			M0_LOG(M0_INFO, "Skipping "FID_F, FID_P(pver_to_skip));
 			continue;
 		}
+#ifdef ENABLE_ALT_PVERS
 		if (!m0_conf_pver_is_clean(pver))
 			continue;
+#endif
 		if (pver->pv_kind == M0_CONF_PVER_ACTUAL) {
 			*out = pver;
 			return M0_RC(0);
 		}
+#ifdef ENABLE_ALT_PVERS
 		return M0_RC(conf_pver_formulate(pver, out));
+#endif
 	} m0_tl_endfor;
 	return M0_ERR_INFO(-ENOENT, "No suitable pver is found at pool "FID_F,
 			   FID_P(&pool->pl_obj.co_id));
@@ -278,6 +282,7 @@ static int conf_pver_formulaic_base(const struct m0_conf_pver *fpver,
 	return M0_RC(0);
 }
 
+#ifdef ENABLE_ALT_PVERS
 M0_INTERNAL bool m0_conf_pver_is_clean(const struct m0_conf_pver *pver)
 {
 	struct m0_conf_pver *base = NULL;
@@ -302,6 +307,7 @@ M0_INTERNAL bool m0_conf_pver_is_clean(const struct m0_conf_pver *pver)
 	return M0_RC(m0_forall(i, M0_CONF_PVER_HEIGHT,
 			       recd[i] == allowance[i]));
 }
+#endif
 
 enum { CONF_PVER_FID_MASK = 0x003fffffffffffffULL };
 

conf/pvers.h

@@ -182,13 +182,15 @@ m0_conf_pver_formulaic_from_virtual(const struct m0_conf_pver *virtual,
 				    const struct m0_conf_root *root,
 				    const struct m0_conf_pver **out);
 
+#ifdef ENABLE_ALT_PVERS
 /**
  * Returns true iff pver consists of online elements only or can be
  * used to generate such a pver.
  *
  * @pre  pver is not virtual
  */
 M0_INTERNAL bool m0_conf_pver_is_clean(const struct m0_conf_pver *pver);
+#endif
 
 /**
  * Returns m0_conf_pver fid.

configure.ac

@@ -200,6 +200,7 @@ AH_TEMPLATE([M0_TRACE_HIGHEST_ALLOWED_LEVEL],[Highest trace level that is allowe
 AH_TEMPLATE([M0_DEFAULT_NETWORK],     [Default network transport type.])
 AH_TEMPLATE([M0_LUSTRE_VERSION],      [Autodetected Lustre version represented as integer])
 AH_TEMPLATE([ENABLE_USER_MODE_ONLY],  [Enabling user mode shall avoid kernel deps])
+AH_TEMPLATE([ENABLE_ALT_PVERS],       [Enable alternative pool versions.])
 AH_TEMPLATE([HAVE_JOURNAL_ABORT],     [Have journal_abort() function])
 AH_TEMPLATE([HAVE_FILE_READV],        [Have fops->readv function])
 AH_TEMPLATE([HAVE_FILE_AIO_READ],     [Have fops->aio_read function])
@@ -544,7 +545,13 @@ AC_ARG_WITH([user-mode-only],
 AS_IF([test "x$with_user_mode_only" = xyes],
       [AC_DEFINE([ENABLE_USER_MODE_ONLY])])
 
-
+# alternative-pvers {{{3
+AC_ARG_ENABLE([alternative_pvers],
+        AS_HELP_STRING([--enable-alternative-pvers], [enable alternative pvers]),
+        [], [enable_alternative_pvers=no]
+)
+AS_IF([test x$enable_alternative_pvers = xyes],
+      AC_DEFINE([ENABLE_ALT_PVERS], 1))
 
 # linux {{{3
 AC_ARG_WITH([linux],