From dd322d94a9449915e511b07a5bd0c342e5f72b63 Mon Sep 17 00:00:00 2001
From: Rich Megginson <rmeggins@redhat.com>
Date: Tue, 25 Jun 2013 19:48:17 -0600
Subject: [PATCH 77/99] Ticket #47409 - allow setting db deadlock rejection
policy
https://fedorahosted.org/389/ticket/47409
Reviewed by: nhosoi (Thanks!)
Branch: 389-ds-base-1.2.11
Fix Description: Add the db config attribute nsslapd-db-deadlock-policy. This
takes values from 1-9. The values correspond to the deadlock detector modes
in db.h. These are the valid values to pass to the DBENV->lock_detect
method for the atype parameter. The default value is 9 (DB_LOCK_YOUNGEST) -
select the youngest locker and reject it. A value of 0 (DB_LOCK_NORUN) means
to disable deadlock detection and rejection - not recommended except for
testing purposes. Attempting to use other values will cause an error.
Platforms tested: RHEL6 x86_64
Flag Day: no
Doc impact: yes - document new config parameter
(cherry picked from commit d62cd9b69c8a4a852e7bea0345285dc8c3e1e547)
(cherry picked from commit 42a3ef2644d31355da4d82e1f11b2b2eada554a7)
(cherry picked from commit f7548908d4749db429f17e23c01624475c121def)
---
ldap/servers/slapd/back-ldbm/dblayer.c | 19 +++++++++++-----
ldap/servers/slapd/back-ldbm/dblayer.h | 1 +
ldap/servers/slapd/back-ldbm/ldbm_config.c | 35 ++++++++++++++++++++++++++++++
ldap/servers/slapd/back-ldbm/ldbm_config.h | 2 ++
ldap/servers/slapd/slapi-plugin.h | 3 +++
5 files changed, 54 insertions(+), 6 deletions(-)
diff --git a/ldap/servers/slapd/back-ldbm/dblayer.c b/ldap/servers/slapd/back-ldbm/dblayer.c
index 2fd2110..85e4a18 100644
--- a/ldap/servers/slapd/back-ldbm/dblayer.c
+++ b/ldap/servers/slapd/back-ldbm/dblayer.c
@@ -4206,6 +4206,7 @@ static int deadlock_threadmain(void *param)
dblayer_private *priv = NULL;
struct ldbminfo *li = NULL;
PRIntervalTime interval; /*NSPR timeout stuffy*/
+ u_int32_t flags = 0;
PR_ASSERT(NULL != param);
li = (struct ldbminfo*)param;
@@ -4220,13 +4221,19 @@ static int deadlock_threadmain(void *param)
{
if (priv->dblayer_enable_transactions)
{
- if (dblayer_db_uses_locking(priv->dblayer_env->dblayer_DB_ENV)) {
- int aborted;
- if ((rval = LOCK_DETECT(priv->dblayer_env->dblayer_DB_ENV,
- 0, DB_LOCK_YOUNGEST, &aborted)) != 0) {
+ DB_ENV *db_env = priv->dblayer_env->dblayer_DB_ENV;
+ u_int32_t deadlock_policy = priv->dblayer_deadlock_policy;
+
+ if (dblayer_db_uses_locking(db_env) && (deadlock_policy > DB_LOCK_NORUN)) {
+ int rejected = 0;
+
+ if ((rval = LOCK_DETECT(db_env, 0, deadlock_policy, &rejected)) != 0) {
LDAPDebug(LDAP_DEBUG_ANY,
- "Serious Error---Failed in deadlock detect (aborted at 0x%x), err=%d (%s)\n",
- aborted, rval, dblayer_strerror(rval));
+ "Serious Error---Failed in deadlock detect (aborted at 0x%x), err=%d (%s)\n",
+ rejected, rval, dblayer_strerror(rval));
+ } else if (rejected) {
+ LDAPDebug1Arg(LDAP_DEBUG_TRACE, "deadlock_threadmain: found and rejected %d lock requests\n", rejected);
+
}
}
}
diff --git a/ldap/servers/slapd/back-ldbm/dblayer.h b/ldap/servers/slapd/back-ldbm/dblayer.h
index ab9a85d..7f3200c 100644
--- a/ldap/servers/slapd/back-ldbm/dblayer.h
+++ b/ldap/servers/slapd/back-ldbm/dblayer.h
@@ -178,6 +178,7 @@ struct dblayer_private
PRCondVar *thread_count_cv; /* condition variable for housekeeping thread shutdown */
int dblayer_lockdown; /* use DB_LOCKDOWN */
int dblayer_lock_config;
+ u_int32_t dblayer_deadlock_policy; /* i.e. the atype to DB_ENV->lock_detect in deadlock_threadmain */
};
#if 1000*DB_VERSION_MAJOR + 100*DB_VERSION_MINOR >= 4300
diff --git a/ldap/servers/slapd/back-ldbm/ldbm_config.c b/ldap/servers/slapd/back-ldbm/ldbm_config.c
index eeae22b..44ccf78 100644
--- a/ldap/servers/slapd/back-ldbm/ldbm_config.c
+++ b/ldap/servers/slapd/back-ldbm/ldbm_config.c
@@ -1326,6 +1326,40 @@ static int ldbm_config_db_tx_max_set(
return retval;
}
+static void *ldbm_config_db_deadlock_policy_get(void *arg)
+{
+ struct ldbminfo *li = (struct ldbminfo *) arg;
+
+ return (void *) ((uintptr_t)li->li_dblayer_private->dblayer_deadlock_policy);
+}
+
+static int ldbm_config_db_deadlock_policy_set(void *arg, void *value, char *errorbuf, int phase, int apply)
+{
+ struct ldbminfo *li = (struct ldbminfo *) arg;
+ int retval = LDAP_SUCCESS;
+ u_int32_t val = (u_int32_t) ((uintptr_t)value);
+
+ if ((val < DB_LOCK_NORUN) || (val > DB_LOCK_YOUNGEST)) {
+ PR_snprintf(errorbuf, SLAPI_DSE_RETURNTEXT_SIZE,
+ "Error: Invalid value for %s (%d). Must be between %d and %d inclusive",
+ CONFIG_DB_DEADLOCK_POLICY, val, DB_LOCK_DEFAULT, DB_LOCK_YOUNGEST);
+ LDAPDebug1Arg(LDAP_DEBUG_ANY, "%s\n", errorbuf);
+ return LDAP_UNWILLING_TO_PERFORM;
+ }
+ if (val == DB_LOCK_NORUN) {
+ PR_snprintf(errorbuf, SLAPI_DSE_RETURNTEXT_SIZE,
+ "Warning: Setting value for %s to (%d) will disable deadlock detection",
+ CONFIG_DB_DEADLOCK_POLICY, val);
+ LDAPDebug1Arg(LDAP_DEBUG_ANY, "%s\n", errorbuf);
+ }
+
+ if (apply) {
+ li->li_dblayer_private->dblayer_deadlock_policy = val;
+ }
+
+ return retval;
+}
+
/*------------------------------------------------------------------------
* Configuration array for ldbm and dblayer variables
@@ -1385,6 +1419,7 @@ static config_info ldbm_config[] = {
{CONFIG_PAGEDLOOKTHROUGHLIMIT, CONFIG_TYPE_INT, "0", &ldbm_config_pagedlookthroughlimit_get, &ldbm_config_pagedlookthroughlimit_set, CONFIG_FLAG_ALWAYS_SHOW|CONFIG_FLAG_ALLOW_RUNNING_CHANGE},
{CONFIG_PAGEDIDLISTSCANLIMIT, CONFIG_TYPE_INT, "0", &ldbm_config_pagedallidsthreshold_get, &ldbm_config_pagedallidsthreshold_set, CONFIG_FLAG_ALWAYS_SHOW|CONFIG_FLAG_ALLOW_RUNNING_CHANGE},
{CONFIG_RANGELOOKTHROUGHLIMIT, CONFIG_TYPE_INT, "5000", &ldbm_config_rangelookthroughlimit_get, &ldbm_config_rangelookthroughlimit_set, CONFIG_FLAG_ALWAYS_SHOW|CONFIG_FLAG_ALLOW_RUNNING_CHANGE},
+ {CONFIG_DB_DEADLOCK_POLICY, CONFIG_TYPE_INT, STRINGIFYDEFINE(DB_LOCK_YOUNGEST), &ldbm_config_db_deadlock_policy_get, &ldbm_config_db_deadlock_policy_set, CONFIG_FLAG_ALWAYS_SHOW|CONFIG_FLAG_ALLOW_RUNNING_CHANGE},
{NULL, 0, NULL, NULL, NULL, 0}
};
diff --git a/ldap/servers/slapd/back-ldbm/ldbm_config.h b/ldap/servers/slapd/back-ldbm/ldbm_config.h
index 33eb078..553d387 100644
--- a/ldap/servers/slapd/back-ldbm/ldbm_config.h
+++ b/ldap/servers/slapd/back-ldbm/ldbm_config.h
@@ -159,6 +159,8 @@ struct config_info {
#define CONFIG_USE_LEGACY_ERRORCODE "nsslapd-do-not-use-vlv-error"
+#define CONFIG_DB_DEADLOCK_POLICY "nsslapd-db-deadlock-policy"
+
#define CONFIG_LDBM_DN "cn=config,cn=ldbm database,cn=plugins,cn=config"
#define LDBM_INSTANCE_CONFIG_DONT_WRITE 1
diff --git a/ldap/servers/slapd/slapi-plugin.h b/ldap/servers/slapd/slapi-plugin.h
index 0f69c0a..5b3e1ab 100644
--- a/ldap/servers/slapd/slapi-plugin.h
+++ b/ldap/servers/slapd/slapi-plugin.h
@@ -107,6 +107,9 @@ NSPR_API(PRUint32) PR_fprintf(struct PRFileDesc* fd, const char *fmt, ...)
#define BERLEN_T "u"
#endif
+#define DEFINETOSTR(xxx) #xxx
+#define STRINGIFYDEFINE(xxx) DEFINETOSTR(xxx)
+
/* Common check on berval before accessing the contents. */
/* bv is a struct berval *bv */
#define BV_HAS_DATA(bv) ((bv != NULL) && (bv->bv_len > 0) && (bv->bv_val != NULL))
--
1.8.1.4