diff options
| -rw-r--r-- | drivers/staging/lustre/lustre/include/lustre_mdc.h | 37 | ||||
| -rw-r--r-- | drivers/staging/lustre/lustre/include/obd.h | 41 | ||||
| -rw-r--r-- | drivers/staging/lustre/lustre/llite/llite_lib.c | 3 |
3 files changed, 67 insertions, 14 deletions
diff --git a/drivers/staging/lustre/lustre/include/lustre_mdc.h b/drivers/staging/lustre/lustre/include/lustre_mdc.h index 9549fb498747..8fc2d3f2dfd6 100644 --- a/drivers/staging/lustre/lustre/include/lustre_mdc.h +++ b/drivers/staging/lustre/lustre/include/lustre_mdc.h @@ -156,26 +156,41 @@ static inline void mdc_put_rpc_lock(struct mdc_rpc_lock *lck, mutex_unlock(&lck->rpcl_mutex); } -/* Update the maximum observed easize and cookiesize. The default easize - * and cookiesize is initialized to the minimum value but allowed to grow - * up to a single page in size if required to handle the common case. +/** + * Update the maximum possible easize and cookiesize. + * + * The values are learned from ptlrpc replies sent by the MDT. The + * default easize and cookiesize is initialized to the minimum value but + * allowed to grow up to a single page in size if required to handle the + * common case. + * + * \see client_obd::cl_default_mds_easize and + * client_obd::cl_default_mds_cookiesize + * + * \param[in] exp export for MDC device + * \param[in] body body of ptlrpc reply from MDT + * */ static inline void mdc_update_max_ea_from_body(struct obd_export *exp, struct mdt_body *body) { if (body->mbo_valid & OBD_MD_FLMODEASIZE) { struct client_obd *cli = &exp->exp_obd->u.cli; + u32 def_cookiesize, def_easize; - if (cli->cl_max_mds_easize < body->mbo_max_mdsize) { + if (cli->cl_max_mds_easize < body->mbo_max_mdsize) cli->cl_max_mds_easize = body->mbo_max_mdsize; - cli->cl_default_mds_easize = - min_t(__u32, body->mbo_max_mdsize, PAGE_SIZE); - } - if (cli->cl_max_mds_cookiesize < body->mbo_max_cookiesize) { + + def_easize = min_t(__u32, body->mbo_max_mdsize, + OBD_MAX_DEFAULT_EA_SIZE); + cli->cl_default_mds_easize = def_easize; + + if (cli->cl_max_mds_cookiesize < body->mbo_max_cookiesize) cli->cl_max_mds_cookiesize = body->mbo_max_cookiesize; - cli->cl_default_mds_cookiesize = - min_t(__u32, body->mbo_max_cookiesize, PAGE_SIZE); - } + + def_cookiesize = min_t(__u32, body->mbo_max_cookiesize, + OBD_MAX_DEFAULT_COOKIE_SIZE); + cli->cl_default_mds_cookiesize = def_cookiesize; } } diff --git a/drivers/staging/lustre/lustre/include/obd.h b/drivers/staging/lustre/lustre/include/obd.h index ef1153492272..f6fc4dd05bd6 100644 --- a/drivers/staging/lustre/lustre/include/obd.h +++ b/drivers/staging/lustre/lustre/include/obd.h @@ -196,6 +196,16 @@ enum obd_cl_sem_lock_class { OBD_CLI_SEM_MDCOSC, }; +/* + * Limit reply buffer size for striping data to one x86_64 page. This + * value is chosen to fit the striping data for common use cases while + * staying well below the limit at which the buffer must be backed by + * vmalloc(). Excessive use of vmalloc() may cause spinlock contention + * on the MDS. + */ +#define OBD_MAX_DEFAULT_EA_SIZE 4096 +#define OBD_MAX_DEFAULT_COOKIE_SIZE 4096 + struct mdc_rpc_lock; struct obd_import; struct client_obd { @@ -203,12 +213,39 @@ struct client_obd { struct obd_uuid cl_target_uuid; struct obd_import *cl_import; /* ptlrpc connection state */ size_t cl_conn_count; - /* max_mds_easize is purely a performance thing so we don't have to - * call obd_size_diskmd() all the time. + /* + * Cache maximum and default values for easize and cookiesize. This is + * strictly a performance optimization to minimize calls to + * obd_size_diskmd(). The default values are used to calculate the + * initial size of a request buffer. The ptlrpc layer will resize the + * buffer as needed to accommodate a larger reply from the + * server. The default values should be small enough to avoid wasted + * memory and excessive use of vmalloc(), yet large enough to avoid + * reallocating the buffer in the common use case. + */ + /* + * Default EA size for striping attributes. It is initialized at + * mount-time based on the default stripe width of the filesystem, + * then it tracks the largest observed EA size advertised by + * the MDT, up to a maximum value of OBD_MAX_DEFAULT_EA_SIZE. */ u32 cl_default_mds_easize; + /* Maximum possible EA size computed at mount-time based on + * the number of OSTs in the filesystem. May be increased at + * run-time if a larger observed size is advertised by the MDT. + */ u32 cl_max_mds_easize; + /* Default cookie size for llog cookies (see struct llog_cookie). It is + * initialized to zero at mount-time, then it tracks the largest + * observed cookie size advertised by the MDT, up to a maximum value of + * OBD_MAX_DEFAULT_COOKIE_SIZE. Note that llog_cookies are not + * used by clients communicating with MDS versions 2.4.0 and later. + */ u32 cl_default_mds_cookiesize; + /* Maximum possible cookie size computed at mount-time based on + * the number of OSTs in the filesystem. May be increased at + * run-time if a larger observed size is advertised by the MDT. + */ u32 cl_max_mds_cookiesize; enum lustre_sec_part cl_sp_me; diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c index ab004093ed4e..6bb41b09172e 100644 --- a/drivers/staging/lustre/lustre/llite/llite_lib.c +++ b/drivers/staging/lustre/lustre/llite/llite_lib.c @@ -619,7 +619,8 @@ int ll_get_default_mdsize(struct ll_sb_info *sbi, int *lmmsize) */ int ll_set_default_mdsize(struct ll_sb_info *sbi, int lmmsize) { - if (lmmsize < sizeof(struct lov_mds_md) || lmmsize > PAGE_SIZE) + if (lmmsize < sizeof(struct lov_mds_md) || + lmmsize > OBD_MAX_DEFAULT_EA_SIZE) return -EINVAL; return obd_set_info_async(NULL, sbi->ll_md_exp, |