-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
* GPL HEADER START
*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
/*
* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
#include "osc_cl_internal.h"
-/** \addtogroup osc
- * @{
+static void osc_lru_del(struct client_obd *cli, struct osc_page *opg, bool del);
+static void osc_lru_add(struct client_obd *cli, struct osc_page *opg);
+static int osc_lru_reserve(const struct lu_env *env, struct osc_object *obj,
+ struct osc_page *opg);
+
+/** \addtogroup osc
+ * @{
*/
-/*
+/*
* Comment out osc_page_protected because it may sleep inside the
* the client_obd_list_lock.
* client_obd_list_lock -> osc_ap_completion -> osc_completion ->
descr->cld_mode = mode;
descr->cld_start = page->cp_index;
descr->cld_end = page->cp_index;
- cfs_spin_lock(&hdr->coh_lock_guard);
+ spin_lock(&hdr->coh_lock_guard);
cfs_list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) {
/*
* Lock-less sub-lock has to be either in HELD state
break;
}
}
- cfs_spin_unlock(&hdr->coh_lock_guard);
+ spin_unlock(&hdr->coh_lock_guard);
}
return result;
}
{
struct osc_page *opg = cl2osc_page(slice);
CDEBUG(D_TRACE, "%p\n", opg);
- OBD_SLAB_FREE_PTR(opg, osc_page_kmem);
+ LASSERT(opg->ops_lock == NULL);
}
static void osc_page_transfer_get(struct osc_page *opg, const char *label)
static void osc_page_transfer_add(const struct lu_env *env,
struct osc_page *opg, enum cl_req_type crt)
{
- struct osc_object *obj;
+ struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
- LINVRNT(cl_page_is_vmlocked(env, opg->ops_cl.cpl_page));
+ /* ops_lru and ops_inflight share the same field, so take it from LRU
+ * first and then use it as inflight. */
+ osc_lru_del(osc_cli(obj), opg, false);
- obj = cl2osc(opg->ops_cl.cpl_obj);
- cfs_spin_lock(&obj->oo_seatbelt);
- cfs_list_add(&opg->ops_inflight, &obj->oo_inflight[crt]);
- opg->ops_submitter = cfs_current();
- cfs_spin_unlock(&obj->oo_seatbelt);
+ spin_lock(&obj->oo_seatbelt);
+ cfs_list_add(&opg->ops_inflight, &obj->oo_inflight[crt]);
+ opg->ops_submitter = cfs_current();
+ spin_unlock(&obj->oo_seatbelt);
}
static int osc_page_cache_add(const struct lu_env *env,
- const struct cl_page_slice *slice,
- struct cl_io *unused)
+ const struct cl_page_slice *slice,
+ struct cl_io *io)
{
- struct osc_page *opg = cl2osc_page(slice);
- struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
- int result;
- /* All cacheable IO is async-capable */
- int brw_flags = OBD_BRW_ASYNC;
- int noquota = 0;
-
- LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 0));
- ENTRY;
-
- /* Set the OBD_BRW_SRVLOCK before the page is queued. */
- brw_flags |= opg->ops_srvlock ? OBD_BRW_SRVLOCK : 0;
- if (!client_is_remote(osc_export(obj)) &&
- cfs_capable(CFS_CAP_SYS_RESOURCE)) {
- brw_flags |= OBD_BRW_NOQUOTA;
- noquota = OBD_BRW_NOQUOTA;
- }
-
- osc_page_transfer_get(opg, "transfer\0cache");
- result = osc_queue_async_io(env, osc_export(obj), NULL, obj->oo_oinfo,
- &opg->ops_oap, OBD_BRW_WRITE | noquota,
- 0, 0, brw_flags, 0);
- if (result != 0)
- osc_page_transfer_put(env, opg);
- else
- osc_page_transfer_add(env, opg, CRT_WRITE);
- RETURN(result);
+ struct osc_io *oio = osc_env_io(env);
+ struct osc_page *opg = cl2osc_page(slice);
+ int result;
+ ENTRY;
+
+ LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 0));
+
+ osc_page_transfer_get(opg, "transfer\0cache");
+ result = osc_queue_async_io(env, io, opg);
+ if (result != 0)
+ osc_page_transfer_put(env, opg);
+ else
+ osc_page_transfer_add(env, opg, CRT_WRITE);
+
+ /* for sync write, kernel will wait for this page to be flushed before
+ * osc_io_end() is called, so release it earlier.
+ * for mkwrite(), it's known there is no further pages. */
+ if (cl_io_is_sync_write(io) || cl_io_is_mkwrite(io)) {
+ if (oio->oi_active != NULL) {
+ osc_extent_release(env, oio->oi_active);
+ oio->oi_active = NULL;
+ }
+ }
+
+ RETURN(result);
}
void osc_index2policy(ldlm_policy_data_t *policy, const struct cl_object *obj,
policy->l_extent.end = cl_offset(obj, end + 1) - 1;
}
+static int osc_page_addref_lock(const struct lu_env *env,
+ struct osc_page *opg,
+ struct cl_lock *lock)
+{
+ struct osc_lock *olock;
+ int rc;
+
+ LASSERT(opg->ops_lock == NULL);
+
+ olock = osc_lock_at(lock);
+ if (cfs_atomic_inc_return(&olock->ols_pageref) <= 0) {
+ cfs_atomic_dec(&olock->ols_pageref);
+ rc = -ENODATA;
+ } else {
+ cl_lock_get(lock);
+ opg->ops_lock = lock;
+ rc = 0;
+ }
+ return rc;
+}
+
+static void osc_page_putref_lock(const struct lu_env *env,
+ struct osc_page *opg)
+{
+ struct cl_lock *lock = opg->ops_lock;
+ struct osc_lock *olock;
+
+ LASSERT(lock != NULL);
+ olock = osc_lock_at(lock);
+
+ cfs_atomic_dec(&olock->ols_pageref);
+ opg->ops_lock = NULL;
+
+ cl_lock_put(env, lock);
+}
+
static int osc_page_is_under_lock(const struct lu_env *env,
const struct cl_page_slice *slice,
struct cl_io *unused)
{
struct cl_lock *lock;
- int result;
+ int result = -ENODATA;
ENTRY;
lock = cl_lock_at_page(env, slice->cpl_obj, slice->cpl_page,
NULL, 1, 0);
if (lock != NULL) {
- cl_lock_put(env, lock);
- result = -EBUSY;
- } else
- result = -ENODATA;
+ if (osc_page_addref_lock(env, cl2osc_page(slice), lock) == 0)
+ result = -EBUSY;
+ cl_lock_put(env, lock);
+ }
RETURN(result);
}
+static void osc_page_disown(const struct lu_env *env,
+ const struct cl_page_slice *slice,
+ struct cl_io *io)
+{
+ struct osc_page *opg = cl2osc_page(slice);
+
+ if (unlikely(opg->ops_lock))
+ osc_page_putref_lock(env, opg);
+}
+
+static void osc_page_completion_read(const struct lu_env *env,
+ const struct cl_page_slice *slice,
+ int ioret)
+{
+ struct osc_page *opg = cl2osc_page(slice);
+ struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
+
+ if (likely(opg->ops_lock))
+ osc_page_putref_lock(env, opg);
+ osc_lru_add(osc_cli(obj), opg);
+}
+
+static void osc_page_completion_write(const struct lu_env *env,
+ const struct cl_page_slice *slice,
+ int ioret)
+{
+ struct osc_page *opg = cl2osc_page(slice);
+ struct osc_object *obj = cl2osc(slice->cpl_obj);
+
+ osc_lru_add(osc_cli(obj), opg);
+}
+
static int osc_page_fail(const struct lu_env *env,
const struct cl_page_slice *slice,
struct cl_io *unused)
struct osc_async_page *oap = &opg->ops_oap;
struct osc_object *obj = cl2osc(slice->cpl_obj);
struct client_obd *cli = &osc_export(obj)->exp_obd->u.cli;
- struct lov_oinfo *loi = obj->oo_oinfo;
return (*printer)(env, cookie, LUSTRE_OSC_NAME"-page@%p: "
- "1< %#x %d %u %s %s %s > "
- "2< "LPU64" %u %#x %#x | %p %p %p %p %p > "
- "3< %s %p %d %lu %d > "
- "4< %d %d %d %lu %s | %s %s %s %s > "
- "5< %s %s %s %s | %d %s %s | %d %s %s>\n",
+ "1< %#x %d %u %s %s > "
+ "2< "LPU64" %u %u %#x %#x | %p %p %p > "
+ "3< %s %p %d %lu %d > "
+ "4< %d %d %d %lu %s | %s %s %s %s > "
+ "5< %s %s %s %s | %d %s | %d %s %s>\n",
opg,
/* 1 */
oap->oap_magic, oap->oap_cmd,
oap->oap_interrupted,
osc_list(&oap->oap_pending_item),
- osc_list(&oap->oap_urgent_item),
osc_list(&oap->oap_rpc_item),
/* 2 */
- oap->oap_obj_off, oap->oap_page_off,
+ oap->oap_obj_off, oap->oap_page_off, oap->oap_count,
oap->oap_async_flags, oap->oap_brw_flags,
- oap->oap_request,
- oap->oap_cli, oap->oap_loi, oap->oap_caller_ops,
- oap->oap_caller_data,
+ oap->oap_request, oap->oap_cli, obj,
/* 3 */
osc_list(&opg->ops_inflight),
opg->ops_submitter, opg->ops_transfer_pinned,
osc_list(&cli->cl_loi_write_list),
osc_list(&cli->cl_loi_read_list),
/* 5 */
- osc_list(&loi->loi_ready_item),
- osc_list(&loi->loi_hp_ready_item),
- osc_list(&loi->loi_write_item),
- osc_list(&loi->loi_read_item),
- loi->loi_read_lop.lop_num_pending,
- osc_list(&loi->loi_read_lop.lop_pending),
- osc_list(&loi->loi_read_lop.lop_urgent),
- loi->loi_write_lop.lop_num_pending,
- osc_list(&loi->loi_write_lop.lop_pending),
- osc_list(&loi->loi_write_lop.lop_urgent));
+ osc_list(&obj->oo_ready_item),
+ osc_list(&obj->oo_hp_ready_item),
+ osc_list(&obj->oo_write_item),
+ osc_list(&obj->oo_read_item),
+ cfs_atomic_read(&obj->oo_nr_reads),
+ osc_list(&obj->oo_reading_exts),
+ cfs_atomic_read(&obj->oo_nr_writes),
+ osc_list(&obj->oo_hp_exts),
+ osc_list(&obj->oo_urgent_exts));
}
static void osc_page_delete(const struct lu_env *env,
const struct cl_page_slice *slice)
{
- struct osc_page *opg = cl2osc_page(slice);
- struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
- struct osc_async_page *oap = &opg->ops_oap;
+ struct osc_page *opg = cl2osc_page(slice);
+ struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
int rc;
LINVRNT(opg->ops_temp || osc_page_protected(env, opg, CLM_READ, 1));
ENTRY;
CDEBUG(D_TRACE, "%p\n", opg);
osc_page_transfer_put(env, opg);
- rc = osc_teardown_async_page(osc_export(obj), NULL, obj->oo_oinfo, oap);
+ rc = osc_teardown_async_page(env, obj, opg);
if (rc) {
CL_PAGE_DEBUG(D_ERROR, env, cl_page_top(slice->cpl_page),
"Trying to teardown failed: %d\n", rc);
LASSERT(0);
}
- cfs_spin_lock(&obj->oo_seatbelt);
- cfs_list_del_init(&opg->ops_inflight);
- cfs_spin_unlock(&obj->oo_seatbelt);
- EXIT;
+
+ spin_lock(&obj->oo_seatbelt);
+ if (opg->ops_submitter != NULL) {
+ LASSERT(!cfs_list_empty(&opg->ops_inflight));
+ cfs_list_del_init(&opg->ops_inflight);
+ opg->ops_submitter = NULL;
+ }
+ spin_unlock(&obj->oo_seatbelt);
+
+ osc_lru_del(osc_cli(obj), opg, true);
+ EXIT;
}
void osc_page_clip(const struct lu_env *env, const struct cl_page_slice *slice,
opg->ops_from = from;
opg->ops_to = to;
- cfs_spin_lock(&oap->oap_lock);
- oap->oap_async_flags |= ASYNC_COUNT_STABLE;
- cfs_spin_unlock(&oap->oap_lock);
+ spin_lock(&oap->oap_lock);
+ oap->oap_async_flags |= ASYNC_COUNT_STABLE;
+ spin_unlock(&oap->oap_lock);
}
static int osc_page_cancel(const struct lu_env *env,
const struct cl_page_slice *slice)
{
- struct osc_page *opg = cl2osc_page(slice);
- struct osc_async_page *oap = &opg->ops_oap;
+ struct osc_page *opg = cl2osc_page(slice);
int rc = 0;
LINVRNT(osc_page_protected(env, opg, CLM_READ, 0));
- client_obd_list_lock(&oap->oap_cli->cl_loi_list_lock);
/* Check if the transferring against this page
* is completed, or not even queued. */
if (opg->ops_transfer_pinned)
/* FIXME: may not be interrupted.. */
- rc = osc_oap_interrupted(env, oap);
+ rc = osc_cancel_async_page(env, opg);
LASSERT(ergo(rc == 0, opg->ops_transfer_pinned == 0));
- client_obd_list_unlock(&oap->oap_cli->cl_loi_list_lock);
return rc;
}
+static int osc_page_flush(const struct lu_env *env,
+ const struct cl_page_slice *slice,
+ struct cl_io *io)
+{
+ struct osc_page *opg = cl2osc_page(slice);
+ int rc = 0;
+ ENTRY;
+ rc = osc_flush_async_page(env, io, opg);
+ RETURN(rc);
+}
+
static const struct cl_page_operations osc_page_ops = {
.cpo_fini = osc_page_fini,
.cpo_print = osc_page_print,
.cpo_delete = osc_page_delete,
.cpo_is_under_lock = osc_page_is_under_lock,
+ .cpo_disown = osc_page_disown,
.io = {
[CRT_READ] = {
- .cpo_cache_add = osc_page_fail
+ .cpo_cache_add = osc_page_fail,
+ .cpo_completion = osc_page_completion_read
},
[CRT_WRITE] = {
- .cpo_cache_add = osc_page_cache_add
- }
- },
- .cpo_clip = osc_page_clip,
- .cpo_cancel = osc_page_cancel
+ .cpo_cache_add = osc_page_cache_add,
+ .cpo_completion = osc_page_completion_write
+ }
+ },
+ .cpo_clip = osc_page_clip,
+ .cpo_cancel = osc_page_cancel,
+ .cpo_flush = osc_page_flush
};
-static int osc_make_ready(const struct lu_env *env, void *data, int cmd)
+int osc_page_init(const struct lu_env *env, struct cl_object *obj,
+ struct cl_page *page, cfs_page_t *vmpage)
{
- struct osc_page *opg = data;
- struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page);
- int result;
+ struct osc_object *osc = cl2osc(obj);
+ struct osc_page *opg = cl_object_page_slice(obj, page);
+ int result;
+
+ opg->ops_from = 0;
+ opg->ops_to = CFS_PAGE_SIZE;
+
+ result = osc_prep_async_page(osc, opg, vmpage,
+ cl_offset(obj, page->cp_index));
+ if (result == 0) {
+ struct osc_io *oio = osc_env_io(env);
+ opg->ops_srvlock = osc_io_srvlock(oio);
+ cl_page_slice_add(page, &opg->ops_cl, obj,
+ &osc_page_ops);
+ }
+ /*
+ * Cannot assert osc_page_protected() here as read-ahead
+ * creates temporary pages outside of a lock.
+ */
+#ifdef INVARIANT_CHECK
+ opg->ops_temp = !osc_page_protected(env, opg, CLM_READ, 1);
+#endif
+ /* ops_inflight and ops_lru are the same field, but it doesn't
+ * hurt to initialize it twice :-) */
+ CFS_INIT_LIST_HEAD(&opg->ops_inflight);
+ CFS_INIT_LIST_HEAD(&opg->ops_lru);
- LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */
- LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 1));
+ /* reserve an LRU space for this page */
+ if (page->cp_type == CPT_CACHEABLE && result == 0)
+ result = osc_lru_reserve(env, osc, opg);
- ENTRY;
- result = cl_page_make_ready(env, page, CRT_WRITE);
- if (result == 0)
- opg->ops_submit_time = cfs_time_current();
- RETURN(result);
+ return result;
}
-static int osc_refresh_count(const struct lu_env *env, void *data, int cmd)
+/**
+ * Helper function called by osc_io_submit() for every page in an immediate
+ * transfer (i.e., transferred synchronously).
+ */
+void osc_page_submit(const struct lu_env *env, struct osc_page *opg,
+ enum cl_req_type crt, int brw_flags)
{
- struct cl_page *page;
- struct osc_page *osc = data;
- struct cl_object *obj;
- struct cl_attr *attr = &osc_env_info(env)->oti_attr;
-
- int result;
- loff_t kms;
-
- LINVRNT(osc_page_protected(env, osc, CLM_READ, 1));
-
- /* readpage queues with _COUNT_STABLE, shouldn't get here. */
- LASSERT(!(cmd & OBD_BRW_READ));
- LASSERT(osc != NULL);
- page = osc->ops_cl.cpl_page;
- obj = osc->ops_cl.cpl_obj;
-
- cl_object_attr_lock(obj);
- result = cl_object_attr_get(env, obj, attr);
- cl_object_attr_unlock(obj);
- if (result < 0)
- return result;
- kms = attr->cat_kms;
- if (cl_offset(obj, page->cp_index) >= kms)
- /* catch race with truncate */
- return 0;
- else if (cl_offset(obj, page->cp_index + 1) > kms)
- /* catch sub-page write at end of file */
- return kms % CFS_PAGE_SIZE;
- else
- return CFS_PAGE_SIZE;
+ struct osc_async_page *oap = &opg->ops_oap;
+ struct osc_object *obj = oap->oap_obj;
+
+ LINVRNT(osc_page_protected(env, opg,
+ crt == CRT_WRITE ? CLM_WRITE : CLM_READ, 1));
+
+ LASSERTF(oap->oap_magic == OAP_MAGIC, "Bad oap magic: oap %p, "
+ "magic 0x%x\n", oap, oap->oap_magic);
+ LASSERT(oap->oap_async_flags & ASYNC_READY);
+ LASSERT(oap->oap_async_flags & ASYNC_COUNT_STABLE);
+
+ oap->oap_cmd = crt == CRT_WRITE ? OBD_BRW_WRITE : OBD_BRW_READ;
+ oap->oap_page_off = opg->ops_from;
+ oap->oap_count = opg->ops_to - opg->ops_from;
+ oap->oap_brw_flags = OBD_BRW_SYNC | brw_flags;
+
+ if (!client_is_remote(osc_export(obj)) &&
+ cfs_capable(CFS_CAP_SYS_RESOURCE)) {
+ oap->oap_brw_flags |= OBD_BRW_NOQUOTA;
+ oap->oap_cmd |= OBD_BRW_NOQUOTA;
+ }
+
+ opg->ops_submit_time = cfs_time_current();
+ osc_page_transfer_get(opg, "transfer\0imm");
+ osc_page_transfer_add(env, opg, crt);
}
-static int osc_completion(const struct lu_env *env,
- void *data, int cmd, struct obdo *oa, int rc)
+/* --------------- LRU page management ------------------ */
+
+/* OSC is a natural place to manage LRU pages as applications are specialized
+ * to write OSC by OSC. Ideally, if one OSC is used more frequently it should
+ * occupy more LRU slots. On the other hand, we should avoid using up all LRU
+ * slots (client_obd::cl_lru_left) otherwise process has to be put into sleep
+ * for free LRU slots - this will be very bad so the algorithm requires each
+ * OSC to free slots voluntarily to maintain a reasonable number of free slots
+ * at any time.
+ */
+
+static CFS_DECL_WAITQ(osc_lru_waitq);
+static cfs_atomic_t osc_lru_waiters = CFS_ATOMIC_INIT(0);
+/* LRU pages are freed in batch mode. OSC should at least free this
+ * number of pages to avoid running out of LRU budget, and.. */
+static const int lru_shrink_min = 2 << (20 - CFS_PAGE_SHIFT); /* 2M */
+/* free this number at most otherwise it will take too long time to finsih. */
+static const int lru_shrink_max = 32 << (20 - CFS_PAGE_SHIFT); /* 32M */
+
+/* Check if we can free LRU slots from this OSC. If there exists LRU waiters,
+ * we should free slots aggressively. In this way, slots are freed in a steady
+ * step to maintain fairness among OSCs.
+ *
+ * Return how many LRU pages should be freed. */
+static int osc_cache_too_much(struct client_obd *cli)
{
- struct osc_page *opg = data;
- struct osc_async_page *oap = &opg->ops_oap;
- struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page);
- struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj);
- enum cl_req_type crt;
+ struct cl_client_cache *cache = cli->cl_cache;
+ int pages = cfs_atomic_read(&cli->cl_lru_in_list) >> 1;
- LINVRNT(osc_page_protected(env, opg, CLM_READ, 1));
- LINVRNT(cl_page_is_vmlocked(env, page));
+ if (cfs_atomic_read(&osc_lru_waiters) > 0 &&
+ cfs_atomic_read(cli->cl_lru_left) < lru_shrink_max)
+ /* drop lru pages aggressively */
+ return min(pages, lru_shrink_max);
- ENTRY;
+ /* if it's going to run out LRU slots, we should free some, but not
+ * too much to maintain faireness among OSCs. */
+ if (cfs_atomic_read(cli->cl_lru_left) < cache->ccc_lru_max >> 4) {
+ unsigned long tmp;
- cmd &= ~OBD_BRW_NOQUOTA;
- LASSERT(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ));
- LASSERT(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE));
- LASSERT(opg->ops_transfer_pinned);
+ tmp = cache->ccc_lru_max / cfs_atomic_read(&cache->ccc_users);
+ if (pages > tmp)
+ return min(pages, lru_shrink_max);
- /*
- * page->cp_req can be NULL if io submission failed before
- * cl_req was allocated.
- */
- if (page->cp_req != NULL)
- cl_req_page_done(env, page);
- LASSERT(page->cp_req == NULL);
-
- /* As the transfer for this page is being done, clear the flags */
- cfs_spin_lock(&oap->oap_lock);
- oap->oap_async_flags = 0;
- cfs_spin_unlock(&oap->oap_lock);
-
- crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE;
- /* Clear opg->ops_transfer_pinned before VM lock is released. */
- opg->ops_transfer_pinned = 0;
-
- cfs_spin_lock(&obj->oo_seatbelt);
- LASSERT(opg->ops_submitter != NULL);
- LASSERT(!cfs_list_empty(&opg->ops_inflight));
- cfs_list_del_init(&opg->ops_inflight);
- cfs_spin_unlock(&obj->oo_seatbelt);
-
- opg->ops_submit_time = 0;
-
- cl_page_completion(env, page, crt, rc);
-
- /* statistic */
- if (rc == 0 && oap->oap_brw_flags & OBD_BRW_SRVLOCK) {
- struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev;
- struct osc_stats *stats = &lu2osc_dev(ld)->od_stats;
- int bytes = opg->ops_to - opg->ops_from;
-
- if (crt == CRT_READ)
- stats->os_lockless_reads += bytes;
- else
- stats->os_lockless_writes += bytes;
- }
+ return pages > lru_shrink_min ? lru_shrink_min : 0;
+ }
- /*
- * This has to be the last operation with the page, as locks are
- * released in cl_page_completion() and nothing except for the
- * reference counter protects page from concurrent reclaim.
- */
- lu_ref_del(&page->cp_reference, "transfer", page);
- /*
- * As page->cp_obj is pinned by a reference from page->cp_req, it is
- * safe to call cl_page_put() without risking object destruction in a
- * non-blocking context.
- */
- cl_page_put(env, page);
- RETURN(0);
+ return 0;
}
-const static struct obd_async_page_ops osc_async_page_ops = {
- .ap_make_ready = osc_make_ready,
- .ap_refresh_count = osc_refresh_count,
- .ap_completion = osc_completion
-};
-
-struct cl_page *osc_page_init(const struct lu_env *env,
- struct cl_object *obj,
- struct cl_page *page, cfs_page_t *vmpage)
+/* Return how many pages are not discarded in @pvec. */
+static int discard_pagevec(const struct lu_env *env, struct cl_io *io,
+ struct cl_page **pvec, int max_index)
{
- struct osc_object *osc = cl2osc(obj);
- struct osc_page *opg;
- int result;
-
- OBD_SLAB_ALLOC_PTR_GFP(opg, osc_page_kmem, CFS_ALLOC_IO);
- if (opg != NULL) {
- void *oap = &opg->ops_oap;
-
- opg->ops_from = 0;
- opg->ops_to = CFS_PAGE_SIZE;
-
- result = osc_prep_async_page(osc_export(osc),
- NULL, osc->oo_oinfo, vmpage,
- cl_offset(obj, page->cp_index),
- &osc_async_page_ops,
- opg, (void **)&oap, 1, NULL);
- if (result == 0) {
- struct osc_io *oio = osc_env_io(env);
- opg->ops_srvlock = osc_io_srvlock(oio);
- cl_page_slice_add(page, &opg->ops_cl, obj,
- &osc_page_ops);
- }
- /*
- * Cannot assert osc_page_protected() here as read-ahead
- * creates temporary pages outside of a lock.
- */
-#ifdef INVARIANT_CHECK
- opg->ops_temp = !osc_page_protected(env, opg, CLM_READ, 1);
-#endif
- CFS_INIT_LIST_HEAD(&opg->ops_inflight);
- } else
- result = -ENOMEM;
- return ERR_PTR(result);
+ int count;
+ int i;
+
+ for (count = 0, i = 0; i < max_index; i++) {
+ struct cl_page *page = pvec[i];
+ if (cl_page_own_try(env, io, page) == 0) {
+ /* free LRU page only if nobody is using it.
+ * This check is necessary to avoid freeing the pages
+ * having already been removed from LRU and pinned
+ * for IO. */
+ if (!cl_page_in_use(page)) {
+ cl_page_unmap(env, io, page);
+ cl_page_discard(env, io, page);
+ ++count;
+ }
+ cl_page_disown(env, io, page);
+ }
+ cl_page_put(env, page);
+ pvec[i] = NULL;
+ }
+ return max_index - count;
}
/**
- * Helper function called by osc_io_submit() for every page in an immediate
- * transfer (i.e., transferred synchronously).
+ * Drop @target of pages from LRU at most.
*/
-void osc_io_submit_page(const struct lu_env *env,
- struct osc_io *oio, struct osc_page *opg,
- enum cl_req_type crt)
+int osc_lru_shrink(struct client_obd *cli, int target)
{
- struct osc_async_page *oap = &opg->ops_oap;
- struct client_obd *cli = oap->oap_cli;
- int flags = 0;
-
- LINVRNT(osc_page_protected(env, opg,
- crt == CRT_WRITE ? CLM_WRITE : CLM_READ, 1));
-
- oap->oap_page_off = opg->ops_from;
- oap->oap_count = opg->ops_to - opg->ops_from;
- /* Give a hint to OST that requests are coming from kswapd - bug19529 */
- if (cfs_memory_pressure_get())
- oap->oap_brw_flags |= OBD_BRW_MEMALLOC;
- oap->oap_brw_flags |= OBD_BRW_SYNC;
- if (osc_io_srvlock(oio))
- oap->oap_brw_flags |= OBD_BRW_SRVLOCK;
-
- oap->oap_cmd = crt == CRT_WRITE ? OBD_BRW_WRITE : OBD_BRW_READ;
- if (!client_is_remote(osc_export(cl2osc(opg->ops_cl.cpl_obj))) &&
- cfs_capable(CFS_CAP_SYS_RESOURCE)) {
- oap->oap_brw_flags |= OBD_BRW_NOQUOTA;
- oap->oap_cmd |= OBD_BRW_NOQUOTA;
- }
+ struct cl_env_nest nest;
+ struct lu_env *env;
+ struct cl_io *io;
+ struct cl_object *clobj = NULL;
+ struct cl_page **pvec;
+ struct osc_page *opg;
+ int maxscan = 0;
+ int count = 0;
+ int index = 0;
+ int rc = 0;
+ ENTRY;
+
+ LASSERT(cfs_atomic_read(&cli->cl_lru_in_list) >= 0);
+ if (cfs_atomic_read(&cli->cl_lru_in_list) == 0 || target <= 0)
+ RETURN(0);
+
+ env = cl_env_nested_get(&nest);
+ if (IS_ERR(env))
+ RETURN(PTR_ERR(env));
+
+ pvec = osc_env_info(env)->oti_pvec;
+ io = &osc_env_info(env)->oti_io;
+
+ client_obd_list_lock(&cli->cl_lru_list_lock);
+ cfs_atomic_inc(&cli->cl_lru_shrinkers);
+ maxscan = min(target << 1, cfs_atomic_read(&cli->cl_lru_in_list));
+ while (!cfs_list_empty(&cli->cl_lru_list)) {
+ struct cl_page *page;
+
+ if (--maxscan < 0)
+ break;
+
+ opg = cfs_list_entry(cli->cl_lru_list.next, struct osc_page,
+ ops_lru);
+ page = cl_page_top(opg->ops_cl.cpl_page);
+ if (cl_page_in_use_noref(page)) {
+ cfs_list_move_tail(&opg->ops_lru, &cli->cl_lru_list);
+ continue;
+ }
+
+ LASSERT(page->cp_obj != NULL);
+ if (clobj != page->cp_obj) {
+ struct cl_object *tmp = page->cp_obj;
+
+ cl_object_get(tmp);
+ client_obd_list_unlock(&cli->cl_lru_list_lock);
+
+ if (clobj != NULL) {
+ count -= discard_pagevec(env, io, pvec, index);
+ index = 0;
+
+ cl_io_fini(env, io);
+ cl_object_put(env, clobj);
+ clobj = NULL;
+ }
+
+ clobj = tmp;
+ io->ci_obj = clobj;
+ io->ci_ignore_layout = 1;
+ rc = cl_io_init(env, io, CIT_MISC, clobj);
+
+ client_obd_list_lock(&cli->cl_lru_list_lock);
+
+ if (rc != 0)
+ break;
+
+ ++maxscan;
+ continue;
+ }
+
+ /* move this page to the end of list as it will be discarded
+ * soon. The page will be finally removed from LRU list in
+ * osc_page_delete(). */
+ cfs_list_move_tail(&opg->ops_lru, &cli->cl_lru_list);
+
+ /* it's okay to grab a refcount here w/o holding lock because
+ * it has to grab cl_lru_list_lock to delete the page. */
+ cl_page_get(page);
+ pvec[index++] = page;
+ if (++count >= target)
+ break;
+
+ if (unlikely(index == OTI_PVEC_SIZE)) {
+ client_obd_list_unlock(&cli->cl_lru_list_lock);
+ count -= discard_pagevec(env, io, pvec, index);
+ index = 0;
+
+ client_obd_list_lock(&cli->cl_lru_list_lock);
+ }
+ }
+ client_obd_list_unlock(&cli->cl_lru_list_lock);
+
+ if (clobj != NULL) {
+ count -= discard_pagevec(env, io, pvec, index);
+
+ cl_io_fini(env, io);
+ cl_object_put(env, clobj);
+ }
+ cl_env_nested_put(&nest, env);
+
+ cfs_atomic_dec(&cli->cl_lru_shrinkers);
+ RETURN(count > 0 ? count : rc);
+}
+
+static void osc_lru_add(struct client_obd *cli, struct osc_page *opg)
+{
+ bool wakeup = false;
+
+ if (!opg->ops_in_lru)
+ return;
+
+ cfs_atomic_dec(&cli->cl_lru_busy);
+ client_obd_list_lock(&cli->cl_lru_list_lock);
+ if (cfs_list_empty(&opg->ops_lru)) {
+ cfs_list_move_tail(&opg->ops_lru, &cli->cl_lru_list);
+ cfs_atomic_inc_return(&cli->cl_lru_in_list);
+ wakeup = cfs_atomic_read(&osc_lru_waiters) > 0;
+ }
+ client_obd_list_unlock(&cli->cl_lru_list_lock);
+
+ if (wakeup) {
+ osc_lru_shrink(cli, osc_cache_too_much(cli));
+ cfs_waitq_broadcast(&osc_lru_waitq);
+ }
+}
+
+/* delete page from LRUlist. The page can be deleted from LRUlist for two
+ * reasons: redirtied or deleted from page cache. */
+static void osc_lru_del(struct client_obd *cli, struct osc_page *opg, bool del)
+{
+ if (opg->ops_in_lru) {
+ client_obd_list_lock(&cli->cl_lru_list_lock);
+ if (!cfs_list_empty(&opg->ops_lru)) {
+ LASSERT(cfs_atomic_read(&cli->cl_lru_in_list) > 0);
+ cfs_list_del_init(&opg->ops_lru);
+ cfs_atomic_dec(&cli->cl_lru_in_list);
+ if (!del)
+ cfs_atomic_inc(&cli->cl_lru_busy);
+ } else if (del) {
+ LASSERT(cfs_atomic_read(&cli->cl_lru_busy) > 0);
+ cfs_atomic_dec(&cli->cl_lru_busy);
+ }
+ client_obd_list_unlock(&cli->cl_lru_list_lock);
+ if (del) {
+ cfs_atomic_inc(cli->cl_lru_left);
+ /* this is a great place to release more LRU pages if
+ * this osc occupies too many LRU pages and kernel is
+ * stealing one of them.
+ * cl_lru_shrinkers is to avoid recursive call in case
+ * we're already in the context of osc_lru_shrink(). */
+ if (cfs_atomic_read(&cli->cl_lru_shrinkers) == 0)
+ osc_lru_shrink(cli, osc_cache_too_much(cli));
+ cfs_waitq_signal(&osc_lru_waitq);
+ }
+ } else {
+ LASSERT(cfs_list_empty(&opg->ops_lru));
+ }
+}
- if (oap->oap_cmd & OBD_BRW_READ)
- flags = ASYNC_COUNT_STABLE;
- else if (!(oap->oap_brw_page.flag & OBD_BRW_FROM_GRANT))
- osc_enter_cache_try(env, cli, oap->oap_loi, oap, 1);
+static inline int max_to_shrink(struct client_obd *cli)
+{
+ return min(cfs_atomic_read(&cli->cl_lru_in_list) >> 1, lru_shrink_max);
+}
- cfs_spin_lock(&oap->oap_lock);
- oap->oap_async_flags |= OSC_FLAGS | flags;
- cfs_spin_unlock(&oap->oap_lock);
+static int osc_lru_reclaim(struct client_obd *cli)
+{
+ struct cl_client_cache *cache = cli->cl_cache;
+ int max_scans;
+ int rc;
+
+ LASSERT(cache != NULL);
+ LASSERT(!cfs_list_empty(&cache->ccc_lru));
+
+ rc = osc_lru_shrink(cli, lru_shrink_min);
+ if (rc != 0) {
+ CDEBUG(D_CACHE, "%s: Free %d pages from own LRU: %p.\n",
+ cli->cl_import->imp_obd->obd_name, rc, cli);
+ return rc;
+ }
+
+ CDEBUG(D_CACHE, "%s: cli %p no free slots, pages: %d, busy: %d.\n",
+ cli->cl_import->imp_obd->obd_name, cli,
+ cfs_atomic_read(&cli->cl_lru_in_list),
+ cfs_atomic_read(&cli->cl_lru_busy));
+
+ /* Reclaim LRU slots from other client_obd as it can't free enough
+ * from its own. This should rarely happen. */
+ spin_lock(&cache->ccc_lru_lock);
+ cache->ccc_lru_shrinkers++;
+ cfs_list_move_tail(&cli->cl_lru_osc, &cache->ccc_lru);
+
+ max_scans = cfs_atomic_read(&cache->ccc_users);
+ while (--max_scans > 0 && !cfs_list_empty(&cache->ccc_lru)) {
+ cli = cfs_list_entry(cache->ccc_lru.next, struct client_obd,
+ cl_lru_osc);
+
+ CDEBUG(D_CACHE, "%s: cli %p LRU pages: %d, busy: %d.\n",
+ cli->cl_import->imp_obd->obd_name, cli,
+ cfs_atomic_read(&cli->cl_lru_in_list),
+ cfs_atomic_read(&cli->cl_lru_busy));
+
+ cfs_list_move_tail(&cli->cl_lru_osc, &cache->ccc_lru);
+ if (cfs_atomic_read(&cli->cl_lru_in_list) > 0) {
+ spin_unlock(&cache->ccc_lru_lock);
+
+ rc = osc_lru_shrink(cli, max_to_shrink(cli));
+ spin_lock(&cache->ccc_lru_lock);
+ if (rc != 0)
+ break;
+ }
+ }
+ spin_unlock(&cache->ccc_lru_lock);
+
+ CDEBUG(D_CACHE, "%s: cli %p freed %d pages.\n",
+ cli->cl_import->imp_obd->obd_name, cli, rc);
+ return rc;
+}
- osc_oap_to_pending(oap);
- osc_page_transfer_get(opg, "transfer\0imm");
- osc_page_transfer_add(env, opg, crt);
+static int osc_lru_reserve(const struct lu_env *env, struct osc_object *obj,
+ struct osc_page *opg)
+{
+ struct l_wait_info lwi = LWI_INTR(LWI_ON_SIGNAL_NOOP, NULL);
+ struct client_obd *cli = osc_cli(obj);
+ int rc = 0;
+ ENTRY;
+
+ if (cli->cl_cache == NULL) /* shall not be in LRU */
+ RETURN(0);
+
+ LASSERT(cfs_atomic_read(cli->cl_lru_left) >= 0);
+ while (!cfs_atomic_add_unless(cli->cl_lru_left, -1, 0)) {
+ int gen;
+
+ /* run out of LRU spaces, try to drop some by itself */
+ rc = osc_lru_reclaim(cli);
+ if (rc < 0)
+ break;
+ if (rc > 0)
+ continue;
+
+ cfs_cond_resched();
+
+ /* slowest case, all of caching pages are busy, notifying
+ * other OSCs that we're lack of LRU slots. */
+ cfs_atomic_inc(&osc_lru_waiters);
+
+ gen = cfs_atomic_read(&cli->cl_lru_in_list);
+ rc = l_wait_event(osc_lru_waitq,
+ cfs_atomic_read(cli->cl_lru_left) > 0 ||
+ (cfs_atomic_read(&cli->cl_lru_in_list) > 0 &&
+ gen != cfs_atomic_read(&cli->cl_lru_in_list)),
+ &lwi);
+
+ cfs_atomic_dec(&osc_lru_waiters);
+ if (rc < 0)
+ break;
+ }
+
+ if (rc >= 0) {
+ cfs_atomic_inc(&cli->cl_lru_busy);
+ opg->ops_in_lru = 1;
+ rc = 0;
+ }
+
+ RETURN(rc);
}
/** @} osc */
git://git.whamcloud.com / fs / lustre-release.git / blobdiff