| Message ID | 20180917130335.112832-16-trond.myklebust@hammerspace.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Convert RPC client transmission to a queued model | expand |
Hi Trond, I'm seeing this crash while running cthon tests (on any NFS version) after applying this patch: [ 50.780104] general protection fault: 0000 [#1] PREEMPT SMP PTI [ 50.780796] CPU: 0 PID: 384 Comm: kworker/u5:1 Not tainted 4.19.0-rc4-ANNA+ #7455 [ 50.781601] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 50.782232] Workqueue: xprtiod xs_tcp_data_receive_workfn [sunrpc] [ 50.782911] RIP: 0010:xprt_lookup_rqst+0x2c/0x150 [sunrpc] [ 50.783510] Code: 48 8d 97 58 04 00 00 41 54 49 89 fc 55 89 f5 53 48 8b 87 58 04 00 00 48 39 c2 74 26 48 8d 98 48 ff ff ff 3b 70 e0 75 07 eb 3f <39> 68 e0 74 3a 48 8b 83 b8 00 00 00 48 8d 98 48 ff ff ff 48 39 c2 [ 50.785501] RSP: 0018:ffffc90000bebd60 EFLAGS: 00010202 [ 50.786090] RAX: dead000000000100 RBX: dead000000000048 RCX: 0000000000000051 [ 50.786853] RDX: ffff8800b915dc58 RSI: 000000005a1c5631 RDI: ffff8800b915d800 [ 50.787616] RBP: 000000005a1c5631 R08: 0000000000000000 R09: 00646f6974727078 [ 50.788380] R10: 8080808080808080 R11: 00000000000ee5f3 R12: ffff8800b915d800 [ 50.789153] R13: ffff8800b915dc18 R14: ffff8800b915d800 R15: ffffffffa03265b4 [ 50.789930] FS: 0000000000000000(0000) GS:ffff8800bca00000(0000) knlGS:0000000000000000 [ 50.790797] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 50.791416] CR2: 00007f9b670538b0 CR3: 000000000200a001 CR4: 00000000001606f0 [ 50.792182] Call Trace: [ 50.792471] xs_tcp_data_recv+0x3a6/0x780 [sunrpc] [ 50.792993] ? __switch_to_asm+0x34/0x70 [ 50.793426] ? xs_tcp_check_fraghdr.part.1+0x40/0x40 [sunrpc] [ 50.794047] tcp_read_sock+0x93/0x1b0 [ 50.794447] ? __switch_to_asm+0x40/0x70 [ 50.794879] xs_tcp_data_receive_workfn+0xb2/0x190 [sunrpc] [ 50.795482] process_one_work+0x1e6/0x3c0 [ 50.795928] worker_thread+0x28/0x3c0 [ 50.796337] ? process_one_work+0x3c0/0x3c0 [ 50.796814] kthread+0x10d/0x130 [ 50.797170] ? kthread_park+0x80/0x80 [ 50.797570] ret_from_fork+0x35/0x40 [ 50.797961] Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4 nfs fscache cfg80211 rpcrdma rfkill crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel joydev pcbc mousedev aesni_intel psmouse aes_x86_64 evdev crypto_simd cryptd input_leds glue_helper led_class mac_hid pcspkr intel_agp intel_gtt i2c_piix4 nfsd button auth_rpcgss nfs_acl lockd grace sunrpc sch_fq_codel ip_tables x_tables ata_generic pata_acpi ata_piix serio_raw uhci_hcd atkbd ehci_pci libps2 ehci_hcd libata usbcore usb_common i8042 floppy serio scsi_mod xfs virtio_balloon virtio_net net_failover failover virtio_pci virtio_blk virtio_ring virtio Cheers, Anna On Mon, 2018-09-17 at 09:03 -0400, Trond Myklebust wrote: > Separate out the action of adding a request to the reply queue so that the > backchannel code can simply skip calling it altogether. > > Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> > --- > include/linux/sunrpc/xprt.h | 1 + > net/sunrpc/backchannel_rqst.c | 1 - > net/sunrpc/clnt.c | 5 ++ > net/sunrpc/xprt.c | 126 +++++++++++++++++++----------- > net/sunrpc/xprtrdma/backchannel.c | 1 - > 5 files changed, 88 insertions(+), 46 deletions(-) > > diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h > index c25d0a5fda69..0250294c904a 100644 > --- a/include/linux/sunrpc/xprt.h > +++ b/include/linux/sunrpc/xprt.h > @@ -334,6 +334,7 @@ void xprt_free_slot(struct rpc_xprt > *xprt, > struct rpc_rqst *req); > void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct > rpc_task *task); > bool xprt_prepare_transmit(struct rpc_task *task); > +void xprt_request_enqueue_receive(struct rpc_task *task); > void xprt_transmit(struct rpc_task *task); > void xprt_end_transmit(struct rpc_task *task); > int xprt_adjust_timeout(struct rpc_rqst *req); > diff --git a/net/sunrpc/backchannel_rqst.c b/net/sunrpc/backchannel_rqst.c > index 3c15a99b9700..fa5ba6ed3197 100644 > --- a/net/sunrpc/backchannel_rqst.c > +++ b/net/sunrpc/backchannel_rqst.c > @@ -91,7 +91,6 @@ struct rpc_rqst *xprt_alloc_bc_req(struct rpc_xprt *xprt, > gfp_t gfp_flags) > return NULL; > > req->rq_xprt = xprt; > - INIT_LIST_HEAD(&req->rq_list); > INIT_LIST_HEAD(&req->rq_bc_list); > > /* Preallocate one XDR receive buffer */ > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c > index a858366cd15d..414966273a3f 100644 > --- a/net/sunrpc/clnt.c > +++ b/net/sunrpc/clnt.c > @@ -1962,6 +1962,11 @@ call_transmit(struct rpc_task *task) > return; > } > } > + > + /* Add task to reply queue before transmission to avoid races */ > + if (rpc_reply_expected(task)) > + xprt_request_enqueue_receive(task); > + > if (!xprt_prepare_transmit(task)) > return; > task->tk_action = call_transmit_status; > diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c > index 6e3d4b4ee79e..d8f870b5dd46 100644 > --- a/net/sunrpc/xprt.c > +++ b/net/sunrpc/xprt.c > @@ -888,6 +888,61 @@ static void xprt_wait_on_pinned_rqst(struct rpc_rqst > *req) > wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); > } > > +static bool > +xprt_request_data_received(struct rpc_task *task) > +{ > + return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && > + READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; > +} > + > +static bool > +xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst > *req) > +{ > + return !xprt_request_data_received(task); > +} > + > +/** > + * xprt_request_enqueue_receive - Add an request to the receive queue > + * @task: RPC task > + * > + */ > +void > +xprt_request_enqueue_receive(struct rpc_task *task) > +{ > + struct rpc_rqst *req = task->tk_rqstp; > + struct rpc_xprt *xprt = req->rq_xprt; > + > + if (!xprt_request_need_enqueue_receive(task, req)) > + return; > + spin_lock(&xprt->queue_lock); > + > + /* Update the softirq receive buffer */ > + memcpy(&req->rq_private_buf, &req->rq_rcv_buf, > + sizeof(req->rq_private_buf)); > + > + /* Add request to the receive list */ > + list_add_tail(&req->rq_list, &xprt->recv); > + set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); > + spin_unlock(&xprt->queue_lock); > + > + xprt_reset_majortimeo(req); > + /* Turn off autodisconnect */ > + del_singleshot_timer_sync(&xprt->timer); > +} > + > +/** > + * xprt_request_dequeue_receive_locked - Remove a request from the receive > queue > + * @task: RPC task > + * > + * Caller must hold xprt->queue_lock. > + */ > +static void > +xprt_request_dequeue_receive_locked(struct rpc_task *task) > +{ > + if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) > + list_del(&task->tk_rqstp->rq_list); > +} > + > /** > * xprt_update_rtt - Update RPC RTT statistics > * @task: RPC request that recently completed > @@ -927,24 +982,16 @@ void xprt_complete_rqst(struct rpc_task *task, int > copied) > > xprt->stat.recvs++; > > - list_del_init(&req->rq_list); > req->rq_private_buf.len = copied; > /* Ensure all writes are done before we update */ > /* req->rq_reply_bytes_recvd */ > smp_wmb(); > req->rq_reply_bytes_recvd = copied; > - clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); > + xprt_request_dequeue_receive_locked(task); > rpc_wake_up_queued_task(&xprt->pending, task); > } > EXPORT_SYMBOL_GPL(xprt_complete_rqst); > > -static bool > -xprt_request_data_received(struct rpc_task *task) > -{ > - return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && > - task->tk_rqstp->rq_reply_bytes_recvd != 0; > -} > - > static void xprt_timer(struct rpc_task *task) > { > struct rpc_rqst *req = task->tk_rqstp; > @@ -1018,32 +1065,15 @@ void xprt_transmit(struct rpc_task *task) > > dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); > > - if (!req->rq_reply_bytes_recvd) { > - > + if (!req->rq_bytes_sent) { > + if (xprt_request_data_received(task)) > + return; > /* Verify that our message lies in the RPCSEC_GSS window */ > - if (!req->rq_bytes_sent && rpcauth_xmit_need_reencode(task)) { > + if (rpcauth_xmit_need_reencode(task)) { > task->tk_status = -EBADMSG; > return; > } > - > - if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { > - /* > - * Add to the list only if we're expecting a reply > - */ > - /* Update the softirq receive buffer */ > - memcpy(&req->rq_private_buf, &req->rq_rcv_buf, > - sizeof(req->rq_private_buf)); > - /* Add request to the receive list */ > - spin_lock(&xprt->queue_lock); > - list_add_tail(&req->rq_list, &xprt->recv); > - set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); > - spin_unlock(&xprt->queue_lock); > - xprt_reset_majortimeo(req); > - /* Turn off autodisconnect */ > - del_singleshot_timer_sync(&xprt->timer); > - } > - } else if (xprt_request_data_received(task) && !req->rq_bytes_sent) > - return; > + } > > connect_cookie = xprt->connect_cookie; > status = xprt->ops->send_request(task); > @@ -1285,7 +1315,6 @@ xprt_request_init(struct rpc_task *task) > struct rpc_xprt *xprt = task->tk_xprt; > struct rpc_rqst *req = task->tk_rqstp; > > - INIT_LIST_HEAD(&req->rq_list); > req->rq_timeout = task->tk_client->cl_timeout->to_initval; > req->rq_task = task; > req->rq_xprt = xprt; > @@ -1355,6 +1384,26 @@ void xprt_retry_reserve(struct rpc_task *task) > xprt_do_reserve(xprt, task); > } > > +static void > +xprt_request_dequeue_all(struct rpc_task *task, struct rpc_rqst *req) > +{ > + struct rpc_xprt *xprt = req->rq_xprt; > + > + if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || > + xprt_is_pinned_rqst(req)) { > + spin_lock(&xprt->queue_lock); > + xprt_request_dequeue_receive_locked(task); > + while (xprt_is_pinned_rqst(req)) { > + set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); > + spin_unlock(&xprt->queue_lock); > + xprt_wait_on_pinned_rqst(req); > + spin_lock(&xprt->queue_lock); > + clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); > + } > + spin_unlock(&xprt->queue_lock); > + } > +} > + > /** > * xprt_release - release an RPC request slot > * @task: task which is finished with the slot > @@ -1379,18 +1428,7 @@ void xprt_release(struct rpc_task *task) > task->tk_ops->rpc_count_stats(task, task->tk_calldata); > else if (task->tk_client) > rpc_count_iostats(task, task->tk_client->cl_metrics); > - spin_lock(&xprt->queue_lock); > - if (!list_empty(&req->rq_list)) { > - list_del_init(&req->rq_list); > - if (xprt_is_pinned_rqst(req)) { > - set_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task- > >tk_runstate); > - spin_unlock(&xprt->queue_lock); > - xprt_wait_on_pinned_rqst(req); > - spin_lock(&xprt->queue_lock); > - clear_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task- > >tk_runstate); > - } > - } > - spin_unlock(&xprt->queue_lock); > + xprt_request_dequeue_all(task, req); > spin_lock_bh(&xprt->transport_lock); > xprt->ops->release_xprt(xprt, task); > if (xprt->ops->release_request) > diff --git a/net/sunrpc/xprtrdma/backchannel.c > b/net/sunrpc/xprtrdma/backchannel.c > index 90adeff4c06b..ed58761e6b23 100644 > --- a/net/sunrpc/xprtrdma/backchannel.c > +++ b/net/sunrpc/xprtrdma/backchannel.c > @@ -51,7 +51,6 @@ static int rpcrdma_bc_setup_reqs(struct rpcrdma_xprt > *r_xprt, > rqst = &req->rl_slot; > > rqst->rq_xprt = xprt; > - INIT_LIST_HEAD(&rqst->rq_list); > INIT_LIST_HEAD(&rqst->rq_bc_list); > __set_bit(RPC_BC_PA_IN_USE, &rqst->rq_bc_pa_state); > spin_lock_bh(&xprt->bc_pa_lock);
On Tue, 2018-09-18 at 17:01 -0400, Anna Schumaker wrote: > Hi Trond, > > I'm seeing this crash while running cthon tests (on any NFS version) > after > applying this patch: > > [ 50.780104] general protection fault: 0000 [#1] PREEMPT SMP PTI > [ 50.780796] CPU: 0 PID: 384 Comm: kworker/u5:1 Not tainted 4.19.0- > rc4-ANNA+ > #7455 > [ 50.781601] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > [ 50.782232] Workqueue: xprtiod xs_tcp_data_receive_workfn [sunrpc] > [ 50.782911] RIP: 0010:xprt_lookup_rqst+0x2c/0x150 [sunrpc] > [ 50.783510] Code: 48 8d 97 58 04 00 00 41 54 49 89 fc 55 89 f5 53 > 48 8b 87 58 > 04 00 00 48 39 c2 74 26 48 8d 98 48 ff ff ff 3b 70 e0 75 07 eb 3f > <39> 68 e0 74 > 3a 48 8b 83 b8 00 00 00 48 8d 98 48 ff ff ff 48 39 c2 > [ 50.785501] RSP: 0018:ffffc90000bebd60 EFLAGS: 00010202 > [ 50.786090] RAX: dead000000000100 RBX: dead000000000048 RCX: > 0000000000000051 > [ 50.786853] RDX: ffff8800b915dc58 RSI: 000000005a1c5631 RDI: > ffff8800b915d800 > [ 50.787616] RBP: 000000005a1c5631 R08: 0000000000000000 R09: > 00646f6974727078 > [ 50.788380] R10: 8080808080808080 R11: 00000000000ee5f3 R12: > ffff8800b915d800 > [ 50.789153] R13: ffff8800b915dc18 R14: ffff8800b915d800 R15: > ffffffffa03265b4 > [ 50.789930] FS: 0000000000000000(0000) GS:ffff8800bca00000(0000) > knlGS:0000000000000000 > [ 50.790797] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 50.791416] CR2: 00007f9b670538b0 CR3: 000000000200a001 CR4: > 00000000001606f0 > [ 50.792182] Call Trace: > [ 50.792471] xs_tcp_data_recv+0x3a6/0x780 [sunrpc] > [ 50.792993] ? __switch_to_asm+0x34/0x70 > [ 50.793426] ? xs_tcp_check_fraghdr.part.1+0x40/0x40 [sunrpc] > [ 50.794047] tcp_read_sock+0x93/0x1b0 > [ 50.794447] ? __switch_to_asm+0x40/0x70 > [ 50.794879] xs_tcp_data_receive_workfn+0xb2/0x190 [sunrpc] > [ 50.795482] process_one_work+0x1e6/0x3c0 > [ 50.795928] worker_thread+0x28/0x3c0 > [ 50.796337] ? process_one_work+0x3c0/0x3c0 > [ 50.796814] kthread+0x10d/0x130 > [ 50.797170] ? kthread_park+0x80/0x80 > [ 50.797570] ret_from_fork+0x35/0x40 > [ 50.797961] Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4 nfs > fscache > cfg80211 rpcrdma rfkill crct10dif_pclmul crc32_pclmul crc32c_intel > ghash_clmulni_intel joydev pcbc mousedev aesni_intel psmouse > aes_x86_64 evdev > crypto_simd cryptd input_leds glue_helper led_class mac_hid pcspkr > intel_agp > intel_gtt i2c_piix4 nfsd button auth_rpcgss nfs_acl lockd grace > sunrpc > sch_fq_codel ip_tables x_tables ata_generic pata_acpi ata_piix > serio_raw > uhci_hcd atkbd ehci_pci libps2 ehci_hcd libata usbcore usb_common > i8042 floppy > serio scsi_mod xfs virtio_balloon virtio_net net_failover failover > virtio_pci > virtio_blk virtio_ring virtio > Thanks for finding that! It looks like the definition of xprt_request_need_enqueue_receive() was incorrect so I've pushed out a fixed version to the 'testing' branch.
On Wed, 2018-09-19 at 15:48 +0000, Trond Myklebust wrote: > On Tue, 2018-09-18 at 17:01 -0400, Anna Schumaker wrote: > > Hi Trond, > > > > I'm seeing this crash while running cthon tests (on any NFS version) > > after > > applying this patch: > > > > [ 50.780104] general protection fault: 0000 [#1] PREEMPT SMP PTI > > [ 50.780796] CPU: 0 PID: 384 Comm: kworker/u5:1 Not tainted 4.19.0- > > rc4-ANNA+ > > #7455 > > [ 50.781601] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > > [ 50.782232] Workqueue: xprtiod xs_tcp_data_receive_workfn [sunrpc] > > [ 50.782911] RIP: 0010:xprt_lookup_rqst+0x2c/0x150 [sunrpc] > > [ 50.783510] Code: 48 8d 97 58 04 00 00 41 54 49 89 fc 55 89 f5 53 > > 48 8b 87 58 > > 04 00 00 48 39 c2 74 26 48 8d 98 48 ff ff ff 3b 70 e0 75 07 eb 3f > > <39> 68 e0 74 > > 3a 48 8b 83 b8 00 00 00 48 8d 98 48 ff ff ff 48 39 c2 > > [ 50.785501] RSP: 0018:ffffc90000bebd60 EFLAGS: 00010202 > > [ 50.786090] RAX: dead000000000100 RBX: dead000000000048 RCX: > > 0000000000000051 > > [ 50.786853] RDX: ffff8800b915dc58 RSI: 000000005a1c5631 RDI: > > ffff8800b915d800 > > [ 50.787616] RBP: 000000005a1c5631 R08: 0000000000000000 R09: > > 00646f6974727078 > > [ 50.788380] R10: 8080808080808080 R11: 00000000000ee5f3 R12: > > ffff8800b915d800 > > [ 50.789153] R13: ffff8800b915dc18 R14: ffff8800b915d800 R15: > > ffffffffa03265b4 > > [ 50.789930] FS: 0000000000000000(0000) GS:ffff8800bca00000(0000) > > knlGS:0000000000000000 > > [ 50.790797] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 50.791416] CR2: 00007f9b670538b0 CR3: 000000000200a001 CR4: > > 00000000001606f0 > > [ 50.792182] Call Trace: > > [ 50.792471] xs_tcp_data_recv+0x3a6/0x780 [sunrpc] > > [ 50.792993] ? __switch_to_asm+0x34/0x70 > > [ 50.793426] ? xs_tcp_check_fraghdr.part.1+0x40/0x40 [sunrpc] > > [ 50.794047] tcp_read_sock+0x93/0x1b0 > > [ 50.794447] ? __switch_to_asm+0x40/0x70 > > [ 50.794879] xs_tcp_data_receive_workfn+0xb2/0x190 [sunrpc] > > [ 50.795482] process_one_work+0x1e6/0x3c0 > > [ 50.795928] worker_thread+0x28/0x3c0 > > [ 50.796337] ? process_one_work+0x3c0/0x3c0 > > [ 50.796814] kthread+0x10d/0x130 > > [ 50.797170] ? kthread_park+0x80/0x80 > > [ 50.797570] ret_from_fork+0x35/0x40 > > [ 50.797961] Modules linked in: nfsv3 rpcsec_gss_krb5 nfsv4 nfs > > fscache > > cfg80211 rpcrdma rfkill crct10dif_pclmul crc32_pclmul crc32c_intel > > ghash_clmulni_intel joydev pcbc mousedev aesni_intel psmouse > > aes_x86_64 evdev > > crypto_simd cryptd input_leds glue_helper led_class mac_hid pcspkr > > intel_agp > > intel_gtt i2c_piix4 nfsd button auth_rpcgss nfs_acl lockd grace > > sunrpc > > sch_fq_codel ip_tables x_tables ata_generic pata_acpi ata_piix > > serio_raw > > uhci_hcd atkbd ehci_pci libps2 ehci_hcd libata usbcore usb_common > > i8042 floppy > > serio scsi_mod xfs virtio_balloon virtio_net net_failover failover > > virtio_pci > > virtio_blk virtio_ring virtio > > > > Thanks for finding that! It looks like the definition of > xprt_request_need_enqueue_receive() was incorrect so I've pushed out a > fixed version to the 'testing' branch. The new version works for me, thanks! Anna > > -- > Trond Myklebust > Linux NFS client maintainer, Hammerspace > trond.myklebust@hammerspace.com > >
diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h index c25d0a5fda69..0250294c904a 100644 --- a/include/linux/sunrpc/xprt.h +++ b/include/linux/sunrpc/xprt.h @@ -334,6 +334,7 @@ void xprt_free_slot(struct rpc_xprt *xprt, struct rpc_rqst *req); void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); bool xprt_prepare_transmit(struct rpc_task *task); +void xprt_request_enqueue_receive(struct rpc_task *task); void xprt_transmit(struct rpc_task *task); void xprt_end_transmit(struct rpc_task *task); int xprt_adjust_timeout(struct rpc_rqst *req); diff --git a/net/sunrpc/backchannel_rqst.c b/net/sunrpc/backchannel_rqst.c index 3c15a99b9700..fa5ba6ed3197 100644 --- a/net/sunrpc/backchannel_rqst.c +++ b/net/sunrpc/backchannel_rqst.c @@ -91,7 +91,6 @@ struct rpc_rqst *xprt_alloc_bc_req(struct rpc_xprt *xprt, gfp_t gfp_flags) return NULL; req->rq_xprt = xprt; - INIT_LIST_HEAD(&req->rq_list); INIT_LIST_HEAD(&req->rq_bc_list); /* Preallocate one XDR receive buffer */ diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index a858366cd15d..414966273a3f 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -1962,6 +1962,11 @@ call_transmit(struct rpc_task *task) return; } } + + /* Add task to reply queue before transmission to avoid races */ + if (rpc_reply_expected(task)) + xprt_request_enqueue_receive(task); + if (!xprt_prepare_transmit(task)) return; task->tk_action = call_transmit_status; diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c index 6e3d4b4ee79e..d8f870b5dd46 100644 --- a/net/sunrpc/xprt.c +++ b/net/sunrpc/xprt.c @@ -888,6 +888,61 @@ static void xprt_wait_on_pinned_rqst(struct rpc_rqst *req) wait_var_event(&req->rq_pin, !xprt_is_pinned_rqst(req)); } +static bool +xprt_request_data_received(struct rpc_task *task) +{ + return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && + READ_ONCE(task->tk_rqstp->rq_reply_bytes_recvd) != 0; +} + +static bool +xprt_request_need_enqueue_receive(struct rpc_task *task, struct rpc_rqst *req) +{ + return !xprt_request_data_received(task); +} + +/** + * xprt_request_enqueue_receive - Add an request to the receive queue + * @task: RPC task + * + */ +void +xprt_request_enqueue_receive(struct rpc_task *task) +{ + struct rpc_rqst *req = task->tk_rqstp; + struct rpc_xprt *xprt = req->rq_xprt; + + if (!xprt_request_need_enqueue_receive(task, req)) + return; + spin_lock(&xprt->queue_lock); + + /* Update the softirq receive buffer */ + memcpy(&req->rq_private_buf, &req->rq_rcv_buf, + sizeof(req->rq_private_buf)); + + /* Add request to the receive list */ + list_add_tail(&req->rq_list, &xprt->recv); + set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); + spin_unlock(&xprt->queue_lock); + + xprt_reset_majortimeo(req); + /* Turn off autodisconnect */ + del_singleshot_timer_sync(&xprt->timer); +} + +/** + * xprt_request_dequeue_receive_locked - Remove a request from the receive queue + * @task: RPC task + * + * Caller must hold xprt->queue_lock. + */ +static void +xprt_request_dequeue_receive_locked(struct rpc_task *task) +{ + if (test_and_clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate)) + list_del(&task->tk_rqstp->rq_list); +} + /** * xprt_update_rtt - Update RPC RTT statistics * @task: RPC request that recently completed @@ -927,24 +982,16 @@ void xprt_complete_rqst(struct rpc_task *task, int copied) xprt->stat.recvs++; - list_del_init(&req->rq_list); req->rq_private_buf.len = copied; /* Ensure all writes are done before we update */ /* req->rq_reply_bytes_recvd */ smp_wmb(); req->rq_reply_bytes_recvd = copied; - clear_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); + xprt_request_dequeue_receive_locked(task); rpc_wake_up_queued_task(&xprt->pending, task); } EXPORT_SYMBOL_GPL(xprt_complete_rqst); -static bool -xprt_request_data_received(struct rpc_task *task) -{ - return !test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) && - task->tk_rqstp->rq_reply_bytes_recvd != 0; -} - static void xprt_timer(struct rpc_task *task) { struct rpc_rqst *req = task->tk_rqstp; @@ -1018,32 +1065,15 @@ void xprt_transmit(struct rpc_task *task) dprintk("RPC: %5u xprt_transmit(%u)\n", task->tk_pid, req->rq_slen); - if (!req->rq_reply_bytes_recvd) { - + if (!req->rq_bytes_sent) { + if (xprt_request_data_received(task)) + return; /* Verify that our message lies in the RPCSEC_GSS window */ - if (!req->rq_bytes_sent && rpcauth_xmit_need_reencode(task)) { + if (rpcauth_xmit_need_reencode(task)) { task->tk_status = -EBADMSG; return; } - - if (list_empty(&req->rq_list) && rpc_reply_expected(task)) { - /* - * Add to the list only if we're expecting a reply - */ - /* Update the softirq receive buffer */ - memcpy(&req->rq_private_buf, &req->rq_rcv_buf, - sizeof(req->rq_private_buf)); - /* Add request to the receive list */ - spin_lock(&xprt->queue_lock); - list_add_tail(&req->rq_list, &xprt->recv); - set_bit(RPC_TASK_NEED_RECV, &task->tk_runstate); - spin_unlock(&xprt->queue_lock); - xprt_reset_majortimeo(req); - /* Turn off autodisconnect */ - del_singleshot_timer_sync(&xprt->timer); - } - } else if (xprt_request_data_received(task) && !req->rq_bytes_sent) - return; + } connect_cookie = xprt->connect_cookie; status = xprt->ops->send_request(task); @@ -1285,7 +1315,6 @@ xprt_request_init(struct rpc_task *task) struct rpc_xprt *xprt = task->tk_xprt; struct rpc_rqst *req = task->tk_rqstp; - INIT_LIST_HEAD(&req->rq_list); req->rq_timeout = task->tk_client->cl_timeout->to_initval; req->rq_task = task; req->rq_xprt = xprt; @@ -1355,6 +1384,26 @@ void xprt_retry_reserve(struct rpc_task *task) xprt_do_reserve(xprt, task); } +static void +xprt_request_dequeue_all(struct rpc_task *task, struct rpc_rqst *req) +{ + struct rpc_xprt *xprt = req->rq_xprt; + + if (test_bit(RPC_TASK_NEED_RECV, &task->tk_runstate) || + xprt_is_pinned_rqst(req)) { + spin_lock(&xprt->queue_lock); + xprt_request_dequeue_receive_locked(task); + while (xprt_is_pinned_rqst(req)) { + set_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); + spin_unlock(&xprt->queue_lock); + xprt_wait_on_pinned_rqst(req); + spin_lock(&xprt->queue_lock); + clear_bit(RPC_TASK_MSG_PIN_WAIT, &task->tk_runstate); + } + spin_unlock(&xprt->queue_lock); + } +} + /** * xprt_release - release an RPC request slot * @task: task which is finished with the slot @@ -1379,18 +1428,7 @@ void xprt_release(struct rpc_task *task) task->tk_ops->rpc_count_stats(task, task->tk_calldata); else if (task->tk_client) rpc_count_iostats(task, task->tk_client->cl_metrics); - spin_lock(&xprt->queue_lock); - if (!list_empty(&req->rq_list)) { - list_del_init(&req->rq_list); - if (xprt_is_pinned_rqst(req)) { - set_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate); - spin_unlock(&xprt->queue_lock); - xprt_wait_on_pinned_rqst(req); - spin_lock(&xprt->queue_lock); - clear_bit(RPC_TASK_MSG_PIN_WAIT, &req->rq_task->tk_runstate); - } - } - spin_unlock(&xprt->queue_lock); + xprt_request_dequeue_all(task, req); spin_lock_bh(&xprt->transport_lock); xprt->ops->release_xprt(xprt, task); if (xprt->ops->release_request) diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c index 90adeff4c06b..ed58761e6b23 100644 --- a/net/sunrpc/xprtrdma/backchannel.c +++ b/net/sunrpc/xprtrdma/backchannel.c @@ -51,7 +51,6 @@ static int rpcrdma_bc_setup_reqs(struct rpcrdma_xprt *r_xprt, rqst = &req->rl_slot; rqst->rq_xprt = xprt; - INIT_LIST_HEAD(&rqst->rq_list); INIT_LIST_HEAD(&rqst->rq_bc_list); __set_bit(RPC_BC_PA_IN_USE, &rqst->rq_bc_pa_state); spin_lock_bh(&xprt->bc_pa_lock);
Separate out the action of adding a request to the reply queue so that the backchannel code can simply skip calling it altogether. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> --- include/linux/sunrpc/xprt.h | 1 + net/sunrpc/backchannel_rqst.c | 1 - net/sunrpc/clnt.c | 5 ++ net/sunrpc/xprt.c | 126 +++++++++++++++++++----------- net/sunrpc/xprtrdma/backchannel.c | 1 - 5 files changed, 88 insertions(+), 46 deletions(-)