diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c index a2e1e02005f67f7588db76549b0eaf614e330921..e349a3316303f8b327c237dc421fdba725e1d735 100644 --- a/fs/afs/cmservice.c +++ b/fs/afs/cmservice.c @@ -24,6 +24,11 @@ static int afs_deliver_cb_callback(struct afs_call *); static int afs_deliver_cb_probe_uuid(struct afs_call *); static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *); static void afs_cm_destructor(struct afs_call *); +static void SRXAFSCB_CallBack(struct work_struct *); +static void SRXAFSCB_InitCallBackState(struct work_struct *); +static void SRXAFSCB_Probe(struct work_struct *); +static void SRXAFSCB_ProbeUuid(struct work_struct *); +static void SRXAFSCB_TellMeAboutYourself(struct work_struct *); #define CM_NAME(name) \ const char afs_SRXCB##name##_name[] __tracepoint_string = \ @@ -38,6 +43,7 @@ static const struct afs_call_type afs_SRXCBCallBack = { .deliver = afs_deliver_cb_callback, .abort_to_error = afs_abort_to_error, .destructor = afs_cm_destructor, + .work = SRXAFSCB_CallBack, }; /* @@ -49,6 +55,7 @@ static const struct afs_call_type afs_SRXCBInitCallBackState = { .deliver = afs_deliver_cb_init_call_back_state, .abort_to_error = afs_abort_to_error, .destructor = afs_cm_destructor, + .work = SRXAFSCB_InitCallBackState, }; /* @@ -60,6 +67,7 @@ static const struct afs_call_type afs_SRXCBInitCallBackState3 = { .deliver = afs_deliver_cb_init_call_back_state3, .abort_to_error = afs_abort_to_error, .destructor = afs_cm_destructor, + .work = SRXAFSCB_InitCallBackState, }; /* @@ -71,6 +79,7 @@ static const struct afs_call_type afs_SRXCBProbe = { .deliver = afs_deliver_cb_probe, .abort_to_error = afs_abort_to_error, .destructor = afs_cm_destructor, + .work = SRXAFSCB_Probe, }; /* @@ -82,6 +91,7 @@ static const struct afs_call_type afs_SRXCBProbeUuid = { .deliver = afs_deliver_cb_probe_uuid, .abort_to_error = afs_abort_to_error, .destructor = afs_cm_destructor, + .work = SRXAFSCB_ProbeUuid, }; /* @@ -93,6 +103,7 @@ static const struct afs_call_type afs_SRXCBTellMeAboutYourself = { .deliver = afs_deliver_cb_tell_me_about_yourself, .abort_to_error = afs_abort_to_error, .destructor = afs_cm_destructor, + .work = SRXAFSCB_TellMeAboutYourself, }; /* @@ -163,6 +174,7 @@ static void SRXAFSCB_CallBack(struct work_struct *work) afs_send_empty_reply(call); afs_break_callbacks(call->server, call->count, call->request); + afs_put_call(call); _leave(""); } @@ -284,9 +296,7 @@ static int afs_deliver_cb_callback(struct afs_call *call) return -ENOTCONN; call->server = server; - INIT_WORK(&call->work, SRXAFSCB_CallBack); - queue_work(afs_wq, &call->work); - return 0; + return afs_queue_call_work(call); } /* @@ -300,6 +310,7 @@ static void SRXAFSCB_InitCallBackState(struct work_struct *work) afs_init_callback_state(call->server); afs_send_empty_reply(call); + afs_put_call(call); _leave(""); } @@ -330,9 +341,7 @@ static int afs_deliver_cb_init_call_back_state(struct afs_call *call) return -ENOTCONN; call->server = server; - INIT_WORK(&call->work, SRXAFSCB_InitCallBackState); - queue_work(afs_wq, &call->work); - return 0; + return afs_queue_call_work(call); } /* @@ -404,9 +413,7 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call) return -ENOTCONN; call->server = server; - INIT_WORK(&call->work, SRXAFSCB_InitCallBackState); - queue_work(afs_wq, &call->work); - return 0; + return afs_queue_call_work(call); } /* @@ -418,6 +425,7 @@ static void SRXAFSCB_Probe(struct work_struct *work) _enter(""); afs_send_empty_reply(call); + afs_put_call(call); _leave(""); } @@ -437,9 +445,7 @@ static int afs_deliver_cb_probe(struct afs_call *call) /* no unmarshalling required */ call->state = AFS_CALL_REPLYING; - INIT_WORK(&call->work, SRXAFSCB_Probe); - queue_work(afs_wq, &call->work); - return 0; + return afs_queue_call_work(call); } /* @@ -462,6 +468,7 @@ static void SRXAFSCB_ProbeUuid(struct work_struct *work) reply.match = htonl(1); afs_send_simple_reply(call, &reply, sizeof(reply)); + afs_put_call(call); _leave(""); } @@ -520,9 +527,7 @@ static int afs_deliver_cb_probe_uuid(struct afs_call *call) call->state = AFS_CALL_REPLYING; - INIT_WORK(&call->work, SRXAFSCB_ProbeUuid); - queue_work(afs_wq, &call->work); - return 0; + return afs_queue_call_work(call); } /* @@ -584,7 +589,7 @@ static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work) reply.cap.capcount = htonl(1); reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION); afs_send_simple_reply(call, &reply, sizeof(reply)); - + afs_put_call(call); _leave(""); } @@ -604,7 +609,5 @@ static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call) /* no unmarshalling required */ call->state = AFS_CALL_REPLYING; - INIT_WORK(&call->work, SRXAFSCB_TellMeAboutYourself); - queue_work(afs_wq, &call->work); - return 0; + return afs_queue_call_work(call); } diff --git a/fs/afs/internal.h b/fs/afs/internal.h index b411670d5f6770667f128fa3c859f3ae88636eb9..65504e218d35f78cee408f4e9263d3005d6fdf4c 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -66,7 +66,7 @@ enum afs_call_state { struct afs_call { const struct afs_call_type *type; /* type of call */ wait_queue_head_t waitq; /* processes awaiting completion */ - struct work_struct async_work; /* asynchronous work processor */ + struct work_struct async_work; /* async I/O processor */ struct work_struct work; /* actual work processor */ struct rxrpc_call *rxcall; /* RxRPC call handle */ struct key *key; /* security for this call */ @@ -82,6 +82,7 @@ struct afs_call { pgoff_t first; /* first page in mapping to deal with */ pgoff_t last; /* last page in mapping to deal with */ size_t offset; /* offset into received data store */ + atomic_t usage; enum afs_call_state state; int error; /* error code */ u32 abort_code; /* Remote abort ID or 0 */ @@ -115,6 +116,9 @@ struct afs_call_type { /* clean up a call */ void (*destructor)(struct afs_call *call); + + /* Work function */ + void (*work)(struct work_struct *work); }; /* @@ -591,9 +595,12 @@ extern void afs_proc_cell_remove(struct afs_cell *); * rxrpc.c */ extern struct socket *afs_socket; +extern atomic_t afs_outstanding_calls; extern int afs_open_socket(void); extern void afs_close_socket(void); +extern void afs_put_call(struct afs_call *); +extern int afs_queue_call_work(struct afs_call *); extern int afs_make_call(struct in_addr *, struct afs_call *, gfp_t, bool); extern struct afs_call *afs_alloc_flat_call(const struct afs_call_type *, size_t, size_t); diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c index ec1e41f929d13a972922688808690b0cb8b1afed..95f42872b787ad8f857890b60a581b741f12dfc2 100644 --- a/fs/afs/rxrpc.c +++ b/fs/afs/rxrpc.c @@ -19,9 +19,8 @@ struct socket *afs_socket; /* my RxRPC socket */ static struct workqueue_struct *afs_async_calls; static struct afs_call *afs_spare_incoming_call; -static atomic_t afs_outstanding_calls; +atomic_t afs_outstanding_calls; -static void afs_free_call(struct afs_call *); static void afs_wake_up_call_waiter(struct sock *, struct rxrpc_call *, unsigned long); static int afs_wait_for_call_to_complete(struct afs_call *); static void afs_wake_up_async_call(struct sock *, struct rxrpc_call *, unsigned long); @@ -112,9 +111,11 @@ void afs_close_socket(void) { _enter(""); + kernel_listen(afs_socket, 0); + flush_workqueue(afs_async_calls); + if (afs_spare_incoming_call) { - atomic_inc(&afs_outstanding_calls); - afs_free_call(afs_spare_incoming_call); + afs_put_call(afs_spare_incoming_call); afs_spare_incoming_call = NULL; } @@ -123,7 +124,6 @@ void afs_close_socket(void) TASK_UNINTERRUPTIBLE); _debug("no outstanding calls"); - flush_workqueue(afs_async_calls); kernel_sock_shutdown(afs_socket, SHUT_RDWR); flush_workqueue(afs_async_calls); sock_release(afs_socket); @@ -134,44 +134,79 @@ void afs_close_socket(void) } /* - * free a call + * Allocate a call. */ -static void afs_free_call(struct afs_call *call) +static struct afs_call *afs_alloc_call(const struct afs_call_type *type, + gfp_t gfp) { - _debug("DONE %p{%s} [%d]", - call, call->type->name, atomic_read(&afs_outstanding_calls)); + struct afs_call *call; + int o; - ASSERTCMP(call->rxcall, ==, NULL); - ASSERT(!work_pending(&call->async_work)); - ASSERT(call->type->name != NULL); + call = kzalloc(sizeof(*call), gfp); + if (!call) + return NULL; - kfree(call->request); - kfree(call); + call->type = type; + atomic_set(&call->usage, 1); + INIT_WORK(&call->async_work, afs_process_async_call); + init_waitqueue_head(&call->waitq); - if (atomic_dec_and_test(&afs_outstanding_calls)) - wake_up_atomic_t(&afs_outstanding_calls); + o = atomic_inc_return(&afs_outstanding_calls); + trace_afs_call(call, afs_call_trace_alloc, 1, o, + __builtin_return_address(0)); + return call; } /* - * End a call but do not free it + * Dispose of a reference on a call. */ -static void afs_end_call_nofree(struct afs_call *call) +void afs_put_call(struct afs_call *call) { - if (call->rxcall) { - rxrpc_kernel_end_call(afs_socket, call->rxcall); - call->rxcall = NULL; + int n = atomic_dec_return(&call->usage); + int o = atomic_read(&afs_outstanding_calls); + + trace_afs_call(call, afs_call_trace_put, n + 1, o, + __builtin_return_address(0)); + + ASSERTCMP(n, >=, 0); + if (n == 0) { + ASSERT(!work_pending(&call->async_work)); + ASSERT(call->type->name != NULL); + + if (call->rxcall) { + rxrpc_kernel_end_call(afs_socket, call->rxcall); + call->rxcall = NULL; + } + if (call->type->destructor) + call->type->destructor(call); + + kfree(call->request); + kfree(call); + + o = atomic_dec_return(&afs_outstanding_calls); + trace_afs_call(call, afs_call_trace_free, 0, o, + __builtin_return_address(0)); + if (o == 0) + wake_up_atomic_t(&afs_outstanding_calls); } - if (call->type->destructor) - call->type->destructor(call); } /* - * End a call and free it + * Queue the call for actual work. Returns 0 unconditionally for convenience. */ -static void afs_end_call(struct afs_call *call) +int afs_queue_call_work(struct afs_call *call) { - afs_end_call_nofree(call); - afs_free_call(call); + int u = atomic_inc_return(&call->usage); + + trace_afs_call(call, afs_call_trace_work, u, + atomic_read(&afs_outstanding_calls), + __builtin_return_address(0)); + + INIT_WORK(&call->work, call->type->work); + + if (!queue_work(afs_wq, &call->work)) + afs_put_call(call); + return 0; } /* @@ -182,25 +217,19 @@ struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, { struct afs_call *call; - call = kzalloc(sizeof(*call), GFP_NOFS); + call = afs_alloc_call(type, GFP_NOFS); if (!call) goto nomem_call; - _debug("CALL %p{%s} [%d]", - call, type->name, atomic_read(&afs_outstanding_calls)); - atomic_inc(&afs_outstanding_calls); - - call->type = type; - call->request_size = request_size; - call->reply_max = reply_max; - if (request_size) { + call->request_size = request_size; call->request = kmalloc(request_size, GFP_NOFS); if (!call->request) goto nomem_free; } if (reply_max) { + call->reply_max = reply_max; call->buffer = kmalloc(reply_max, GFP_NOFS); if (!call->buffer) goto nomem_free; @@ -210,7 +239,7 @@ struct afs_call *afs_alloc_flat_call(const struct afs_call_type *type, return call; nomem_free: - afs_free_call(call); + afs_put_call(call); nomem_call: return NULL; } @@ -315,7 +344,6 @@ int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, atomic_read(&afs_outstanding_calls)); call->async = async; - INIT_WORK(&call->async_work, afs_process_async_call); memset(&srx, 0, sizeof(srx)); srx.srx_family = AF_RXRPC; @@ -378,7 +406,7 @@ int afs_make_call(struct in_addr *addr, struct afs_call *call, gfp_t gfp, error_do_abort: rxrpc_kernel_abort_call(afs_socket, rxcall, RX_USER_ABORT, -ret, "KSD"); error_kill_call: - afs_end_call(call); + afs_put_call(call); _leave(" = %d", ret); return ret; } @@ -448,7 +476,7 @@ static void afs_deliver_to_call(struct afs_call *call) done: if (call->state == AFS_CALL_COMPLETE && call->incoming) - afs_end_call(call); + afs_put_call(call); out: _leave(""); return; @@ -505,7 +533,7 @@ static int afs_wait_for_call_to_complete(struct afs_call *call) } _debug("call complete"); - afs_end_call(call); + afs_put_call(call); _leave(" = %d", ret); return ret; } @@ -529,14 +557,25 @@ static void afs_wake_up_async_call(struct sock *sk, struct rxrpc_call *rxcall, unsigned long call_user_ID) { struct afs_call *call = (struct afs_call *)call_user_ID; + int u; trace_afs_notify_call(rxcall, call); call->need_attention = true; - queue_work(afs_async_calls, &call->async_work); + + u = __atomic_add_unless(&call->usage, 1, 0); + if (u != 0) { + trace_afs_call(call, afs_call_trace_wake, u, + atomic_read(&afs_outstanding_calls), + __builtin_return_address(0)); + + if (!queue_work(afs_async_calls, &call->async_work)) + afs_put_call(call); + } } /* - * delete an asynchronous call + * Delete an asynchronous call. The work item carries a ref to the call struct + * that we need to release. */ static void afs_delete_async_call(struct work_struct *work) { @@ -544,13 +583,14 @@ static void afs_delete_async_call(struct work_struct *work) _enter(""); - afs_free_call(call); + afs_put_call(call); _leave(""); } /* - * perform processing on an asynchronous call + * Perform I/O processing on an asynchronous call. The work item carries a ref + * to the call struct that we either need to release or to pass on. */ static void afs_process_async_call(struct work_struct *work) { @@ -566,15 +606,16 @@ static void afs_process_async_call(struct work_struct *work) if (call->state == AFS_CALL_COMPLETE) { call->reply = NULL; - /* kill the call */ - afs_end_call_nofree(call); - - /* we can't just delete the call because the work item may be - * queued */ + /* We have two refs to release - one from the alloc and one + * queued with the work item - and we can't just deallocate the + * call because the work item may be queued again. + */ call->async_work.func = afs_delete_async_call; - queue_work(afs_async_calls, &call->async_work); + if (!queue_work(afs_async_calls, &call->async_work)) + afs_put_call(call); } + afs_put_call(call); _leave(""); } @@ -594,12 +635,10 @@ static void afs_charge_preallocation(struct work_struct *work) for (;;) { if (!call) { - call = kzalloc(sizeof(struct afs_call), GFP_KERNEL); + call = afs_alloc_call(&afs_RXCMxxxx, GFP_KERNEL); if (!call) break; - INIT_WORK(&call->async_work, afs_process_async_call); - call->type = &afs_RXCMxxxx; call->async = true; call->state = AFS_CALL_AWAIT_OP_ID; init_waitqueue_head(&call->waitq); @@ -624,9 +663,8 @@ static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, { struct afs_call *call = (struct afs_call *)user_call_ID; - atomic_inc(&afs_outstanding_calls); call->rxcall = NULL; - afs_free_call(call); + afs_put_call(call); } /* @@ -635,7 +673,6 @@ static void afs_rx_discard_new_call(struct rxrpc_call *rxcall, static void afs_rx_new_call(struct sock *sk, struct rxrpc_call *rxcall, unsigned long user_call_ID) { - atomic_inc(&afs_outstanding_calls); queue_work(afs_wq, &afs_charge_preallocation_work); } @@ -699,7 +736,6 @@ void afs_send_empty_reply(struct afs_call *call) rxrpc_kernel_abort_call(afs_socket, call->rxcall, RX_USER_ABORT, ENOMEM, "KOO"); default: - afs_end_call(call); _leave(" [error]"); return; } @@ -738,7 +774,6 @@ void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len) rxrpc_kernel_abort_call(afs_socket, call->rxcall, RX_USER_ABORT, ENOMEM, "KOO"); } - afs_end_call(call); _leave(" [error]"); } diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h index 845907b04ff442f1457dee0987088c0308d30eb1..8b95c16b70454ac875ef5ee3ff8d9df16b78e48b 100644 --- a/include/trace/events/afs.h +++ b/include/trace/events/afs.h @@ -16,6 +16,51 @@ #include +/* + * Define enums for tracing information. + */ +#ifndef __AFS_DECLARE_TRACE_ENUMS_ONCE_ONLY +#define __AFS_DECLARE_TRACE_ENUMS_ONCE_ONLY + +enum afs_call_trace { + afs_call_trace_alloc, + afs_call_trace_free, + afs_call_trace_put, + afs_call_trace_wake, + afs_call_trace_work, +}; + +#endif /* end __AFS_DECLARE_TRACE_ENUMS_ONCE_ONLY */ + +/* + * Declare tracing information enums and their string mappings for display. + */ +#define afs_call_traces \ + EM(afs_call_trace_alloc, "ALLOC") \ + EM(afs_call_trace_free, "FREE ") \ + EM(afs_call_trace_put, "PUT ") \ + EM(afs_call_trace_wake, "WAKE ") \ + E_(afs_call_trace_work, "WORK ") + +/* + * Export enum symbols via userspace. + */ +#undef EM +#undef E_ +#define EM(a, b) TRACE_DEFINE_ENUM(a); +#define E_(a, b) TRACE_DEFINE_ENUM(a); + +afs_call_traces; + +/* + * Now redefine the EM() and E_() macros to map the enums to the strings that + * will be printed in the output. + */ +#undef EM +#undef E_ +#define EM(a, b) { a, b }, +#define E_(a, b) { a, b } + TRACE_EVENT(afs_recv_data, TP_PROTO(struct afs_call *call, unsigned count, unsigned offset, bool want_more, int ret), @@ -103,6 +148,36 @@ TRACE_EVENT(afs_cb_call, __entry->op) ); +TRACE_EVENT(afs_call, + TP_PROTO(struct afs_call *call, enum afs_call_trace op, + int usage, int outstanding, const void *where), + + TP_ARGS(call, op, usage, outstanding, where), + + TP_STRUCT__entry( + __field(struct afs_call *, call ) + __field(int, op ) + __field(int, usage ) + __field(int, outstanding ) + __field(const void *, where ) + ), + + TP_fast_assign( + __entry->call = call; + __entry->op = op; + __entry->usage = usage; + __entry->outstanding = outstanding; + __entry->where = where; + ), + + TP_printk("c=%p %s u=%d o=%d sp=%pSR", + __entry->call, + __print_symbolic(__entry->op, afs_call_traces), + __entry->usage, + __entry->outstanding, + __entry->where) + ); + #endif /* _TRACE_AFS_H */ /* This part must be outside protection */