From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-it0-f68.google.com ([209.85.214.68]:51239 "EHLO mail-it0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727411AbeIJUDp (ORCPT ); Mon, 10 Sep 2018 16:03:45 -0400 Subject: [PATCH v1 03/22] xprtrdma: Explicitly resetting MRs is no longer necessary From: Chuck Lever To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Mon, 10 Sep 2018 11:09:11 -0400 Message-ID: <20180910150911.10564.94387.stgit@manet.1015granger.net> In-Reply-To: <20180910150040.10564.97487.stgit@manet.1015granger.net> References: <20180910150040.10564.97487.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: When a memory operation fails, the MR's driver state might not match its hardware state. The only reliable recourse is to dereg the MR. This is done in ->ro_recover_mr, which then attempts to allocate a fresh MR to replace the released MR. Since commit e2ac236c0b651 ("xprtrdma: Allocate MRs on demand"), xprtrdma dynamically allocates MRs. It can add more MRs whenever they are needed. That makes it possible to simply release an MR when a memory operation fails, instead of "recovering" it. It will automatically be replaced by the on-demand MR allocator. This commit is a little larger than I wanted, but it replaces ->ro_recover_mr, rb_recovery_lock, rb_recovery_worker, and the rb_stale_mrs list with a generic work queue. Since MRs are no longer orphaned, the mrs_orphaned metric is no longer used. Signed-off-by: Chuck Lever --- include/trace/events/rpcrdma.h | 2 - net/sunrpc/xprtrdma/fmr_ops.c | 124 +++++++++++++++++-------------------- net/sunrpc/xprtrdma/frwr_ops.c | 130 ++++++++++++++------------------------- net/sunrpc/xprtrdma/rpc_rdma.c | 2 - net/sunrpc/xprtrdma/transport.c | 2 - net/sunrpc/xprtrdma/verbs.c | 38 ----------- net/sunrpc/xprtrdma/xprt_rdma.h | 14 ++-- 7 files changed, 114 insertions(+), 198 deletions(-) diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h index 53df203..9906f4d 100644 --- a/include/trace/events/rpcrdma.h +++ b/include/trace/events/rpcrdma.h @@ -655,7 +655,7 @@ DEFINE_MR_EVENT(xprtrdma_dma_map); DEFINE_MR_EVENT(xprtrdma_dma_unmap); DEFINE_MR_EVENT(xprtrdma_remoteinv); -DEFINE_MR_EVENT(xprtrdma_recover_mr); +DEFINE_MR_EVENT(xprtrdma_mr_recycle); /** ** Reply events diff --git a/net/sunrpc/xprtrdma/fmr_ops.c b/net/sunrpc/xprtrdma/fmr_ops.c index db589a2..f1cf3a3 100644 --- a/net/sunrpc/xprtrdma/fmr_ops.c +++ b/net/sunrpc/xprtrdma/fmr_ops.c @@ -49,46 +49,7 @@ enum { return true; } -static int -fmr_op_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr) -{ - static struct ib_fmr_attr fmr_attr = { - .max_pages = RPCRDMA_MAX_FMR_SGES, - .max_maps = 1, - .page_shift = PAGE_SHIFT - }; - - mr->fmr.fm_physaddrs = kcalloc(RPCRDMA_MAX_FMR_SGES, - sizeof(u64), GFP_KERNEL); - if (!mr->fmr.fm_physaddrs) - goto out_free; - - mr->mr_sg = kcalloc(RPCRDMA_MAX_FMR_SGES, - sizeof(*mr->mr_sg), GFP_KERNEL); - if (!mr->mr_sg) - goto out_free; - - sg_init_table(mr->mr_sg, RPCRDMA_MAX_FMR_SGES); - - mr->fmr.fm_mr = ib_alloc_fmr(ia->ri_pd, RPCRDMA_FMR_ACCESS_FLAGS, - &fmr_attr); - if (IS_ERR(mr->fmr.fm_mr)) - goto out_fmr_err; - - INIT_LIST_HEAD(&mr->mr_list); - return 0; - -out_fmr_err: - dprintk("RPC: %s: ib_alloc_fmr returned %ld\n", __func__, - PTR_ERR(mr->fmr.fm_mr)); - -out_free: - kfree(mr->mr_sg); - kfree(mr->fmr.fm_physaddrs); - return -ENOMEM; -} - -static int +static void __fmr_unmap(struct rpcrdma_mr *mr) { LIST_HEAD(l); @@ -97,13 +58,16 @@ enum { list_add(&mr->fmr.fm_mr->list, &l); rc = ib_unmap_fmr(&l); list_del(&mr->fmr.fm_mr->list); - return rc; + if (rc) + pr_err("rpcrdma: final ib_unmap_fmr for %p failed %i\n", + mr, rc); } +/* Release an MR. + */ static void fmr_op_release_mr(struct rpcrdma_mr *mr) { - LIST_HEAD(unmap_list); int rc; kfree(mr->fmr.fm_physaddrs); @@ -112,10 +76,7 @@ enum { /* In case this one was left mapped, try to unmap it * to prevent dealloc_fmr from failing with EBUSY */ - rc = __fmr_unmap(mr); - if (rc) - pr_err("rpcrdma: final ib_unmap_fmr for %p failed %i\n", - mr, rc); + __fmr_unmap(mr); rc = ib_dealloc_fmr(mr->fmr.fm_mr); if (rc) @@ -125,28 +86,16 @@ enum { kfree(mr); } -/* Reset of a single FMR. +/* MRs are dynamically allocated, so simply clean up and release the MR. + * A replacement MR will subsequently be allocated on demand. */ static void -fmr_op_recover_mr(struct rpcrdma_mr *mr) +fmr_mr_recycle_worker(struct work_struct *work) { + struct rpcrdma_mr *mr = container_of(work, struct rpcrdma_mr, mr_recycle); struct rpcrdma_xprt *r_xprt = mr->mr_xprt; - int rc; - /* ORDER: invalidate first */ - rc = __fmr_unmap(mr); - if (rc) - goto out_release; - - /* ORDER: then DMA unmap */ - rpcrdma_mr_unmap_and_put(mr); - - r_xprt->rx_stats.mrs_recovered++; - return; - -out_release: - pr_err("rpcrdma: FMR reset failed (%d), %p released\n", rc, mr); - r_xprt->rx_stats.mrs_orphaned++; + trace_xprtrdma_mr_recycle(mr); trace_xprtrdma_dma_unmap(mr); ib_dma_unmap_sg(r_xprt->rx_ia.ri_device, @@ -154,11 +103,51 @@ enum { spin_lock(&r_xprt->rx_buf.rb_mrlock); list_del(&mr->mr_all); + r_xprt->rx_stats.mrs_recycled++; spin_unlock(&r_xprt->rx_buf.rb_mrlock); - fmr_op_release_mr(mr); } +static int +fmr_op_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr) +{ + static struct ib_fmr_attr fmr_attr = { + .max_pages = RPCRDMA_MAX_FMR_SGES, + .max_maps = 1, + .page_shift = PAGE_SHIFT + }; + + mr->fmr.fm_physaddrs = kcalloc(RPCRDMA_MAX_FMR_SGES, + sizeof(u64), GFP_KERNEL); + if (!mr->fmr.fm_physaddrs) + goto out_free; + + mr->mr_sg = kcalloc(RPCRDMA_MAX_FMR_SGES, + sizeof(*mr->mr_sg), GFP_KERNEL); + if (!mr->mr_sg) + goto out_free; + + sg_init_table(mr->mr_sg, RPCRDMA_MAX_FMR_SGES); + + mr->fmr.fm_mr = ib_alloc_fmr(ia->ri_pd, RPCRDMA_FMR_ACCESS_FLAGS, + &fmr_attr); + if (IS_ERR(mr->fmr.fm_mr)) + goto out_fmr_err; + + INIT_LIST_HEAD(&mr->mr_list); + INIT_WORK(&mr->mr_recycle, fmr_mr_recycle_worker); + return 0; + +out_fmr_err: + dprintk("RPC: %s: ib_alloc_fmr returned %ld\n", __func__, + PTR_ERR(mr->fmr.fm_mr)); + +out_free: + kfree(mr->mr_sg); + kfree(mr->fmr.fm_physaddrs); + return -ENOMEM; +} + /* On success, sets: * ep->rep_attr.cap.max_send_wr * ep->rep_attr.cap.max_recv_wr @@ -312,7 +301,7 @@ enum { r_xprt->rx_stats.local_inv_needed++; rc = ib_unmap_fmr(&unmap_list); if (rc) - goto out_reset; + goto out_release; /* ORDER: Now DMA unmap all of the req's MRs, and return * them to the free MW list. @@ -325,13 +314,13 @@ enum { return; -out_reset: +out_release: pr_err("rpcrdma: ib_unmap_fmr failed (%i)\n", rc); while (!list_empty(mrs)) { mr = rpcrdma_mr_pop(mrs); list_del(&mr->fmr.fm_mr->list); - fmr_op_recover_mr(mr); + rpcrdma_mr_recycle(mr); } } @@ -339,7 +328,6 @@ enum { .ro_map = fmr_op_map, .ro_send = fmr_op_send, .ro_unmap_sync = fmr_op_unmap_sync, - .ro_recover_mr = fmr_op_recover_mr, .ro_open = fmr_op_open, .ro_maxpages = fmr_op_maxpages, .ro_init_mr = fmr_op_init_mr, diff --git a/net/sunrpc/xprtrdma/frwr_ops.c b/net/sunrpc/xprtrdma/frwr_ops.c index 1cc4db5..6594627 100644 --- a/net/sunrpc/xprtrdma/frwr_ops.c +++ b/net/sunrpc/xprtrdma/frwr_ops.c @@ -97,6 +97,44 @@ return false; } +static void +frwr_op_release_mr(struct rpcrdma_mr *mr) +{ + int rc; + + rc = ib_dereg_mr(mr->frwr.fr_mr); + if (rc) + pr_err("rpcrdma: final ib_dereg_mr for %p returned %i\n", + mr, rc); + kfree(mr->mr_sg); + kfree(mr); +} + +/* MRs are dynamically allocated, so simply clean up and release the MR. + * A replacement MR will subsequently be allocated on demand. + */ +static void +frwr_mr_recycle_worker(struct work_struct *work) +{ + struct rpcrdma_mr *mr = container_of(work, struct rpcrdma_mr, mr_recycle); + enum rpcrdma_frwr_state state = mr->frwr.fr_state; + struct rpcrdma_xprt *r_xprt = mr->mr_xprt; + + trace_xprtrdma_mr_recycle(mr); + + if (state != FRWR_FLUSHED_LI) { + trace_xprtrdma_dma_unmap(mr); + ib_dma_unmap_sg(r_xprt->rx_ia.ri_device, + mr->mr_sg, mr->mr_nents, mr->mr_dir); + } + + spin_lock(&r_xprt->rx_buf.rb_mrlock); + list_del(&mr->mr_all); + r_xprt->rx_stats.mrs_recycled++; + spin_unlock(&r_xprt->rx_buf.rb_mrlock); + frwr_op_release_mr(mr); +} + static int frwr_op_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr) { @@ -113,6 +151,7 @@ goto out_list_err; INIT_LIST_HEAD(&mr->mr_list); + INIT_WORK(&mr->mr_recycle, frwr_mr_recycle_worker); sg_init_table(mr->mr_sg, depth); init_completion(&frwr->fr_linv_done); return 0; @@ -131,79 +170,6 @@ return rc; } -static void -frwr_op_release_mr(struct rpcrdma_mr *mr) -{ - int rc; - - rc = ib_dereg_mr(mr->frwr.fr_mr); - if (rc) - pr_err("rpcrdma: final ib_dereg_mr for %p returned %i\n", - mr, rc); - kfree(mr->mr_sg); - kfree(mr); -} - -static int -__frwr_mr_reset(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr) -{ - struct rpcrdma_frwr *frwr = &mr->frwr; - int rc; - - rc = ib_dereg_mr(frwr->fr_mr); - if (rc) { - pr_warn("rpcrdma: ib_dereg_mr status %d, frwr %p orphaned\n", - rc, mr); - return rc; - } - - frwr->fr_mr = ib_alloc_mr(ia->ri_pd, ia->ri_mrtype, - ia->ri_max_frwr_depth); - if (IS_ERR(frwr->fr_mr)) { - pr_warn("rpcrdma: ib_alloc_mr status %ld, frwr %p orphaned\n", - PTR_ERR(frwr->fr_mr), mr); - return PTR_ERR(frwr->fr_mr); - } - - dprintk("RPC: %s: recovered FRWR %p\n", __func__, frwr); - frwr->fr_state = FRWR_IS_INVALID; - return 0; -} - -/* Reset of a single FRWR. Generate a fresh rkey by replacing the MR. - */ -static void -frwr_op_recover_mr(struct rpcrdma_mr *mr) -{ - enum rpcrdma_frwr_state state = mr->frwr.fr_state; - struct rpcrdma_xprt *r_xprt = mr->mr_xprt; - struct rpcrdma_ia *ia = &r_xprt->rx_ia; - int rc; - - rc = __frwr_mr_reset(ia, mr); - if (state != FRWR_FLUSHED_LI) { - trace_xprtrdma_dma_unmap(mr); - ib_dma_unmap_sg(ia->ri_device, - mr->mr_sg, mr->mr_nents, mr->mr_dir); - } - if (rc) - goto out_release; - - rpcrdma_mr_put(mr); - r_xprt->rx_stats.mrs_recovered++; - return; - -out_release: - pr_err("rpcrdma: FRWR reset failed %d, %p released\n", rc, mr); - r_xprt->rx_stats.mrs_orphaned++; - - spin_lock(&r_xprt->rx_buf.rb_mrlock); - list_del(&mr->mr_all); - spin_unlock(&r_xprt->rx_buf.rb_mrlock); - - frwr_op_release_mr(mr); -} - /* On success, sets: * ep->rep_attr.cap.max_send_wr * ep->rep_attr.cap.max_recv_wr @@ -385,7 +351,7 @@ mr = NULL; do { if (mr) - rpcrdma_mr_defer_recovery(mr); + rpcrdma_mr_recycle(mr); mr = rpcrdma_mr_get(r_xprt); if (!mr) return ERR_PTR(-EAGAIN); @@ -452,7 +418,7 @@ out_mapmr_err: pr_err("rpcrdma: failed to map mr %p (%d/%d)\n", frwr->fr_mr, n, mr->mr_nents); - rpcrdma_mr_defer_recovery(mr); + rpcrdma_mr_recycle(mr); return ERR_PTR(-EIO); } @@ -571,7 +537,7 @@ if (bad_wr != first) wait_for_completion(&frwr->fr_linv_done); if (rc) - goto reset_mrs; + goto out_release; /* ORDER: Now DMA unmap all of the MRs, and return * them to the free MR list. @@ -583,22 +549,21 @@ } return; -reset_mrs: +out_release: pr_err("rpcrdma: FRWR invalidate ib_post_send returned %i\n", rc); - /* Find and reset the MRs in the LOCAL_INV WRs that did not + /* Unmap and release the MRs in the LOCAL_INV WRs that did not * get posted. */ while (bad_wr) { frwr = container_of(bad_wr, struct rpcrdma_frwr, fr_invwr); mr = container_of(frwr, struct rpcrdma_mr, frwr); - - __frwr_mr_reset(ia, mr); - bad_wr = bad_wr->next; + + list_del(&mr->mr_list); + frwr_op_release_mr(mr); } - goto unmap; } const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = { @@ -606,7 +571,6 @@ .ro_send = frwr_op_send, .ro_reminv = frwr_op_reminv, .ro_unmap_sync = frwr_op_unmap_sync, - .ro_recover_mr = frwr_op_recover_mr, .ro_open = frwr_op_open, .ro_maxpages = frwr_op_maxpages, .ro_init_mr = frwr_op_init_mr, diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c index 33da912..ec4b1f9 100644 --- a/net/sunrpc/xprtrdma/rpc_rdma.c +++ b/net/sunrpc/xprtrdma/rpc_rdma.c @@ -803,7 +803,7 @@ static bool rpcrdma_results_inline(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr *mr; mr = rpcrdma_mr_pop(&req->rl_registered); - rpcrdma_mr_defer_recovery(mr); + rpcrdma_mr_recycle(mr); } /* This implementation supports the following combinations diff --git a/net/sunrpc/xprtrdma/transport.c b/net/sunrpc/xprtrdma/transport.c index 98cbc7b..3ae73e6 100644 --- a/net/sunrpc/xprtrdma/transport.c +++ b/net/sunrpc/xprtrdma/transport.c @@ -792,7 +792,7 @@ void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq) r_xprt->rx_stats.bad_reply_count, r_xprt->rx_stats.nomsg_call_count); seq_printf(seq, "%lu %lu %lu %lu %lu %lu\n", - r_xprt->rx_stats.mrs_recovered, + r_xprt->rx_stats.mrs_recycled, r_xprt->rx_stats.mrs_orphaned, r_xprt->rx_stats.mrs_allocated, r_xprt->rx_stats.local_inv_needed, diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 5625a50..88fe75e 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -978,39 +978,6 @@ struct rpcrdma_sendctx *rpcrdma_sendctx_get_locked(struct rpcrdma_buffer *buf) } static void -rpcrdma_mr_recovery_worker(struct work_struct *work) -{ - struct rpcrdma_buffer *buf = container_of(work, struct rpcrdma_buffer, - rb_recovery_worker.work); - struct rpcrdma_mr *mr; - - spin_lock(&buf->rb_recovery_lock); - while (!list_empty(&buf->rb_stale_mrs)) { - mr = rpcrdma_mr_pop(&buf->rb_stale_mrs); - spin_unlock(&buf->rb_recovery_lock); - - trace_xprtrdma_recover_mr(mr); - mr->mr_xprt->rx_ia.ri_ops->ro_recover_mr(mr); - - spin_lock(&buf->rb_recovery_lock); - } - spin_unlock(&buf->rb_recovery_lock); -} - -void -rpcrdma_mr_defer_recovery(struct rpcrdma_mr *mr) -{ - struct rpcrdma_xprt *r_xprt = mr->mr_xprt; - struct rpcrdma_buffer *buf = &r_xprt->rx_buf; - - spin_lock(&buf->rb_recovery_lock); - rpcrdma_mr_push(mr, &buf->rb_stale_mrs); - spin_unlock(&buf->rb_recovery_lock); - - schedule_delayed_work(&buf->rb_recovery_worker, 0); -} - -static void rpcrdma_mrs_create(struct rpcrdma_xprt *r_xprt) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; @@ -1142,14 +1109,10 @@ struct rpcrdma_req * buf->rb_bc_srv_max_requests = 0; spin_lock_init(&buf->rb_mrlock); spin_lock_init(&buf->rb_lock); - spin_lock_init(&buf->rb_recovery_lock); INIT_LIST_HEAD(&buf->rb_mrs); INIT_LIST_HEAD(&buf->rb_all); - INIT_LIST_HEAD(&buf->rb_stale_mrs); INIT_DELAYED_WORK(&buf->rb_refresh_worker, rpcrdma_mr_refresh_worker); - INIT_DELAYED_WORK(&buf->rb_recovery_worker, - rpcrdma_mr_recovery_worker); rpcrdma_mrs_create(r_xprt); @@ -1233,7 +1196,6 @@ struct rpcrdma_req * void rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf) { - cancel_delayed_work_sync(&buf->rb_recovery_worker); cancel_delayed_work_sync(&buf->rb_refresh_worker); rpcrdma_sendctxs_destroy(buf); diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 2ca14f7..eae2166 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -280,6 +280,7 @@ struct rpcrdma_mr { u32 mr_handle; u32 mr_length; u64 mr_offset; + struct work_struct mr_recycle; struct list_head mr_all; }; @@ -411,9 +412,6 @@ struct rpcrdma_buffer { u32 rb_bc_max_requests; - spinlock_t rb_recovery_lock; /* protect rb_stale_mrs */ - struct list_head rb_stale_mrs; - struct delayed_work rb_recovery_worker; struct delayed_work rb_refresh_worker; }; #define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia) @@ -452,7 +450,7 @@ struct rpcrdma_stats { unsigned long hardway_register_count; unsigned long failed_marshal_count; unsigned long bad_reply_count; - unsigned long mrs_recovered; + unsigned long mrs_recycled; unsigned long mrs_orphaned; unsigned long mrs_allocated; unsigned long empty_sendctx_q; @@ -481,7 +479,6 @@ struct rpcrdma_memreg_ops { struct list_head *mrs); void (*ro_unmap_sync)(struct rpcrdma_xprt *, struct list_head *); - void (*ro_recover_mr)(struct rpcrdma_mr *mr); int (*ro_open)(struct rpcrdma_ia *, struct rpcrdma_ep *, struct rpcrdma_create_data_internal *); @@ -578,7 +575,12 @@ int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *, struct rpcrdma_mr *rpcrdma_mr_get(struct rpcrdma_xprt *r_xprt); void rpcrdma_mr_put(struct rpcrdma_mr *mr); void rpcrdma_mr_unmap_and_put(struct rpcrdma_mr *mr); -void rpcrdma_mr_defer_recovery(struct rpcrdma_mr *mr); + +static inline void +rpcrdma_mr_recycle(struct rpcrdma_mr *mr) +{ + schedule_work(&mr->mr_recycle); +} struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *); void rpcrdma_buffer_put(struct rpcrdma_req *);