From ad479287b4e637ac098e5ebd5dabfa2826e27d4c Mon Sep 17 00:00:00 2001 From: Prakash Surya Date: Wed, 27 Apr 2016 18:21:06 -0400 Subject: [PATCH] staging: lustre: osc: Use SOFT_SYNC to urge server commit This change adds a BRW page flag, OBD_BRW_SOFT_SYNC. This flag is intended to urge a server to commit a client's unstable pages to stable storage. A client will add this flag to any BRW requests while it is in a state where it has "many" unstable pages pinned in its cache. The server, upon receiving a page with this flag set, *should* begin an async commit. The idea being that, with the proactive async commit, the client's pinned unstable pages will transition into a stable state faster than they would have otherwise. Although, the server side portion of this agreement is still unimplemented, so the OBD_BRW_SOFT_SYNC flag will currently fall on deaf ears. Signed-off-by: Prakash Surya Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2139 Reviewed-on: http://review.whamcloud.com/4375 Reviewed-by: Jinshan Xiong Reviewed-by: Oleg Drokin Signed-off-by: James Simmons Signed-off-by: Greg Kroah-Hartman --- .../lustre/lustre/include/lustre/lustre_idl.h | 5 ++++ drivers/staging/lustre/lustre/osc/osc_cache.c | 3 ++ .../staging/lustre/lustre/osc/osc_internal.h | 1 + drivers/staging/lustre/lustre/osc/osc_page.c | 29 +++++++++++++++++++ .../staging/lustre/lustre/osc/osc_request.c | 3 +- .../staging/lustre/lustre/ptlrpc/wiretest.c | 6 ++++ 6 files changed, 46 insertions(+), 1 deletion(-) diff --git a/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h b/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h index c3565bf0e1fb..26819ee969a5 100644 --- a/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h +++ b/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h @@ -1734,6 +1734,11 @@ void lustre_swab_obd_statfs(struct obd_statfs *os); #define OBD_BRW_MEMALLOC 0x800 /* Client runs in the "kswapd" context */ #define OBD_BRW_OVER_USRQUOTA 0x1000 /* Running out of user quota */ #define OBD_BRW_OVER_GRPQUOTA 0x2000 /* Running out of group quota */ +#define OBD_BRW_SOFT_SYNC 0x4000 /* This flag notifies the server + * that the client is running low on + * space for unstable pages; asking + * it to sync quickly + */ #define OBD_OBJECT_EOF 0xffffffffffffffffULL diff --git a/drivers/staging/lustre/lustre/osc/osc_cache.c b/drivers/staging/lustre/lustre/osc/osc_cache.c index 7d1c2c511458..5a14bea961b4 100644 --- a/drivers/staging/lustre/lustre/osc/osc_cache.c +++ b/drivers/staging/lustre/lustre/osc/osc_cache.c @@ -2437,6 +2437,9 @@ int osc_queue_async_io(const struct lu_env *env, struct cl_io *io, return rc; } + if (osc_over_unstable_soft_limit(cli)) + brw_flags |= OBD_BRW_SOFT_SYNC; + oap->oap_cmd = cmd; oap->oap_page_off = ops->ops_from; oap->oap_count = ops->ops_to - ops->ops_from; diff --git a/drivers/staging/lustre/lustre/osc/osc_internal.h b/drivers/staging/lustre/lustre/osc/osc_internal.h index 39e6138b6479..7fad8278150f 100644 --- a/drivers/staging/lustre/lustre/osc/osc_internal.h +++ b/drivers/staging/lustre/lustre/osc/osc_internal.h @@ -202,6 +202,7 @@ int osc_quotacheck(struct obd_device *unused, struct obd_export *exp, int osc_quota_poll_check(struct obd_export *exp, struct if_quotacheck *qchk); void osc_inc_unstable_pages(struct ptlrpc_request *req); void osc_dec_unstable_pages(struct ptlrpc_request *req); +int osc_over_unstable_soft_limit(struct client_obd *cli); struct ldlm_lock *osc_dlmlock_at_pgoff(const struct lu_env *env, struct osc_object *obj, pgoff_t index, diff --git a/drivers/staging/lustre/lustre/osc/osc_page.c b/drivers/staging/lustre/lustre/osc/osc_page.c index 5ec550855f2e..c29c2eabe39c 100644 --- a/drivers/staging/lustre/lustre/osc/osc_page.c +++ b/drivers/staging/lustre/lustre/osc/osc_page.c @@ -346,6 +346,32 @@ int osc_page_init(const struct lu_env *env, struct cl_object *obj, return result; } +int osc_over_unstable_soft_limit(struct client_obd *cli) +{ + long obd_upages, obd_dpages, osc_upages; + + /* Can't check cli->cl_unstable_count, therefore, no soft limit */ + if (!cli) + return 0; + + obd_upages = atomic_read(&obd_unstable_pages); + obd_dpages = atomic_read(&obd_dirty_pages); + + osc_upages = atomic_read(&cli->cl_unstable_count); + + /* + * obd_max_dirty_pages is the max number of (dirty + unstable) + * pages allowed at any given time. To simulate an unstable page + * only limit, we subtract the current number of dirty pages + * from this max. This difference is roughly the amount of pages + * currently available for unstable pages. Thus, the soft limit + * is half of that difference. Check osc_upages to ensure we don't + * set SOFT_SYNC for OSCs without any outstanding unstable pages. + */ + return osc_upages && + obd_upages >= (obd_max_dirty_pages - obd_dpages) / 2; +} + /** * Helper function called by osc_io_submit() for every page in an immediate * transfer (i.e., transferred synchronously). @@ -369,6 +395,9 @@ void osc_page_submit(const struct lu_env *env, struct osc_page *opg, oap->oap_count = opg->ops_to - opg->ops_from; oap->oap_brw_flags = brw_flags | OBD_BRW_SYNC; + if (osc_over_unstable_soft_limit(oap->oap_cli)) + oap->oap_brw_flags |= OBD_BRW_SOFT_SYNC; + if (!client_is_remote(osc_export(obj)) && capable(CFS_CAP_SYS_RESOURCE)) { oap->oap_brw_flags |= OBD_BRW_NOQUOTA; diff --git a/drivers/staging/lustre/lustre/osc/osc_request.c b/drivers/staging/lustre/lustre/osc/osc_request.c index e8a80eb8f3fc..df06f4f103e4 100644 --- a/drivers/staging/lustre/lustre/osc/osc_request.c +++ b/drivers/staging/lustre/lustre/osc/osc_request.c @@ -1147,7 +1147,8 @@ static inline int can_merge_pages(struct brw_page *p1, struct brw_page *p2) { if (p1->flag != p2->flag) { unsigned mask = ~(OBD_BRW_FROM_GRANT | OBD_BRW_NOCACHE | - OBD_BRW_SYNC | OBD_BRW_ASYNC|OBD_BRW_NOQUOTA); + OBD_BRW_SYNC | OBD_BRW_ASYNC | + OBD_BRW_NOQUOTA | OBD_BRW_SOFT_SYNC); /* warn if we try to combine flags that we don't know to be * safe to combine diff --git a/drivers/staging/lustre/lustre/ptlrpc/wiretest.c b/drivers/staging/lustre/lustre/ptlrpc/wiretest.c index 3ffd2d91f274..87555e494826 100644 --- a/drivers/staging/lustre/lustre/ptlrpc/wiretest.c +++ b/drivers/staging/lustre/lustre/ptlrpc/wiretest.c @@ -1639,6 +1639,12 @@ void lustre_assert_wire_constants(void) OBD_BRW_ASYNC); LASSERTF(OBD_BRW_MEMALLOC == 0x800, "found 0x%.8x\n", OBD_BRW_MEMALLOC); + LASSERTF(OBD_BRW_OVER_USRQUOTA == 0x1000, "found 0x%.8x\n", + OBD_BRW_OVER_USRQUOTA); + LASSERTF(OBD_BRW_OVER_GRPQUOTA == 0x2000, "found 0x%.8x\n", + OBD_BRW_OVER_GRPQUOTA); + LASSERTF(OBD_BRW_SOFT_SYNC == 0x4000, "found 0x%.8x\n", + OBD_BRW_SOFT_SYNC); /* Checks for struct ost_body */ LASSERTF((int)sizeof(struct ost_body) == 208, "found %lld\n", -- 2.39.5