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Diffstat (limited to 'src/core/lib/channel/deadline_filter.c')
| -rw-r--r-- | src/core/lib/channel/deadline_filter.c | 302 |
1 files changed, 302 insertions, 0 deletions
diff --git a/src/core/lib/channel/deadline_filter.c b/src/core/lib/channel/deadline_filter.c new file mode 100644 index 0000000000..079b98a2f8 --- /dev/null +++ b/src/core/lib/channel/deadline_filter.c @@ -0,0 +1,302 @@ +// +// Copyright 2016, Google Inc. +// All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +// + +#include "src/core/lib/channel/deadline_filter.h" + +#include <stdbool.h> +#include <string.h> + +#include <grpc/support/alloc.h> +#include <grpc/support/log.h> +#include <grpc/support/sync.h> +#include <grpc/support/time.h> + +#include "src/core/lib/iomgr/exec_ctx.h" +#include "src/core/lib/iomgr/timer.h" + +// +// grpc_deadline_state +// + +// Timer callback. +static void timer_callback(grpc_exec_ctx* exec_ctx, void* arg, + grpc_error* error) { + grpc_call_element* elem = arg; + grpc_deadline_state* deadline_state = elem->call_data; + gpr_mu_lock(&deadline_state->timer_mu); + deadline_state->timer_pending = false; + gpr_mu_unlock(&deadline_state->timer_mu); + if (error != GRPC_ERROR_CANCELLED) { + gpr_slice msg = gpr_slice_from_static_string("Deadline Exceeded"); + grpc_call_element_send_cancel_with_message( + exec_ctx, elem, GRPC_STATUS_DEADLINE_EXCEEDED, &msg); + gpr_slice_unref(msg); + } + GRPC_CALL_STACK_UNREF(exec_ctx, deadline_state->call_stack, "deadline_timer"); +} + +// Starts the deadline timer. +static void start_timer_if_needed(grpc_exec_ctx* exec_ctx, + grpc_call_element* elem, + gpr_timespec deadline) { + grpc_deadline_state* deadline_state = elem->call_data; + deadline = gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC); + if (gpr_time_cmp(deadline, gpr_inf_future(GPR_CLOCK_MONOTONIC)) != 0) { + // Take a reference to the call stack, to be owned by the timer. + GRPC_CALL_STACK_REF(deadline_state->call_stack, "deadline_timer"); + gpr_mu_lock(&deadline_state->timer_mu); + deadline_state->timer_pending = true; + grpc_timer_init(exec_ctx, &deadline_state->timer, deadline, timer_callback, + elem, gpr_now(GPR_CLOCK_MONOTONIC)); + gpr_mu_unlock(&deadline_state->timer_mu); + } +} + +// Cancels the deadline timer. +static void cancel_timer_if_needed(grpc_exec_ctx* exec_ctx, + grpc_deadline_state* deadline_state) { + gpr_mu_lock(&deadline_state->timer_mu); + if (deadline_state->timer_pending) { + grpc_timer_cancel(exec_ctx, &deadline_state->timer); + deadline_state->timer_pending = false; + } + gpr_mu_unlock(&deadline_state->timer_mu); +} + +// Callback run when the call is complete. +static void on_complete(grpc_exec_ctx* exec_ctx, void* arg, grpc_error* error) { + grpc_deadline_state* deadline_state = arg; + cancel_timer_if_needed(exec_ctx, deadline_state); + // Invoke the next callback. + deadline_state->next_on_complete->cb( + exec_ctx, deadline_state->next_on_complete->cb_arg, error); +} + +// Inject our own on_complete callback into op. +static void inject_on_complete_cb(grpc_deadline_state* deadline_state, + grpc_transport_stream_op* op) { + deadline_state->next_on_complete = op->on_complete; + grpc_closure_init(&deadline_state->on_complete, on_complete, deadline_state); + op->on_complete = &deadline_state->on_complete; +} + +// Callback and associated state for starting the timer after call stack +// initialization has been completed. +struct start_timer_after_init_state { + grpc_call_element* elem; + gpr_timespec deadline; + grpc_closure closure; +}; +static void start_timer_after_init(grpc_exec_ctx* exec_ctx, void* arg, + grpc_error* error) { + struct start_timer_after_init_state* state = arg; + start_timer_if_needed(exec_ctx, state->elem, state->deadline); + gpr_free(state); +} + +void grpc_deadline_state_init(grpc_exec_ctx* exec_ctx, grpc_call_element* elem, + grpc_call_element_args* args) { + grpc_deadline_state* deadline_state = elem->call_data; + memset(deadline_state, 0, sizeof(*deadline_state)); + deadline_state->call_stack = args->call_stack; + gpr_mu_init(&deadline_state->timer_mu); + // Deadline will always be infinite on servers, so the timer will only be + // set on clients with a finite deadline. + const gpr_timespec deadline = + gpr_convert_clock_type(args->deadline, GPR_CLOCK_MONOTONIC); + if (gpr_time_cmp(deadline, gpr_inf_future(GPR_CLOCK_MONOTONIC)) != 0) { + // When the deadline passes, we indicate the failure by sending down + // an op with cancel_error set. However, we can't send down any ops + // until after the call stack is fully initialized. If we start the + // timer here, we have no guarantee that the timer won't pop before + // call stack initialization is finished. To avoid that problem, we + // create a closure to start the timer, and we schedule that closure + // to be run after call stack initialization is done. + struct start_timer_after_init_state* state = gpr_malloc(sizeof(*state)); + state->elem = elem; + state->deadline = deadline; + grpc_closure_init(&state->closure, start_timer_after_init, state); + grpc_exec_ctx_sched(exec_ctx, &state->closure, GRPC_ERROR_NONE, NULL); + } +} + +void grpc_deadline_state_destroy(grpc_exec_ctx* exec_ctx, + grpc_call_element* elem) { + grpc_deadline_state* deadline_state = elem->call_data; + cancel_timer_if_needed(exec_ctx, deadline_state); + gpr_mu_destroy(&deadline_state->timer_mu); +} + +void grpc_deadline_state_client_start_transport_stream_op( + grpc_exec_ctx* exec_ctx, grpc_call_element* elem, + grpc_transport_stream_op* op) { + grpc_deadline_state* deadline_state = elem->call_data; + if (op->cancel_error != GRPC_ERROR_NONE || + op->close_error != GRPC_ERROR_NONE) { + cancel_timer_if_needed(exec_ctx, deadline_state); + } else { + // Make sure we know when the call is complete, so that we can cancel + // the timer. + if (op->recv_trailing_metadata != NULL) { + inject_on_complete_cb(deadline_state, op); + } + } +} + +// +// filter code +// + +// Constructor for channel_data. Used for both client and server filters. +static void init_channel_elem(grpc_exec_ctx* exec_ctx, + grpc_channel_element* elem, + grpc_channel_element_args* args) { + GPR_ASSERT(!args->is_last); +} + +// Destructor for channel_data. Used for both client and server filters. +static void destroy_channel_elem(grpc_exec_ctx* exec_ctx, + grpc_channel_element* elem) {} + +// Call data used for both client and server filter. +typedef struct base_call_data { + grpc_deadline_state deadline_state; +} base_call_data; + +// Additional call data used only for the server filter. +typedef struct server_call_data { + base_call_data base; // Must be first. + // The closure for receiving initial metadata. + grpc_closure recv_initial_metadata_ready; + // Received initial metadata batch. + grpc_metadata_batch* recv_initial_metadata; + // The original recv_initial_metadata_ready closure, which we chain to + // after our own closure is invoked. + grpc_closure* next_recv_initial_metadata_ready; +} server_call_data; + +// Constructor for call_data. Used for both client and server filters. +static grpc_error* init_call_elem(grpc_exec_ctx* exec_ctx, + grpc_call_element* elem, + grpc_call_element_args* args) { + // Note: size of call data is different between client and server. + memset(elem->call_data, 0, elem->filter->sizeof_call_data); + grpc_deadline_state_init(exec_ctx, elem, args); + return GRPC_ERROR_NONE; +} + +// Destructor for call_data. Used for both client and server filters. +static void destroy_call_elem(grpc_exec_ctx* exec_ctx, grpc_call_element* elem, + const grpc_call_final_info* final_info, + void* and_free_memory) { + grpc_deadline_state_destroy(exec_ctx, elem); +} + +// Method for starting a call op for client filter. +static void client_start_transport_stream_op(grpc_exec_ctx* exec_ctx, + grpc_call_element* elem, + grpc_transport_stream_op* op) { + grpc_deadline_state_client_start_transport_stream_op(exec_ctx, elem, op); + // Chain to next filter. + grpc_call_next_op(exec_ctx, elem, op); +} + +// Callback for receiving initial metadata on the server. +static void recv_initial_metadata_ready(grpc_exec_ctx* exec_ctx, void* arg, + grpc_error* error) { + grpc_call_element* elem = arg; + server_call_data* calld = elem->call_data; + // Get deadline from metadata and start the timer if needed. + start_timer_if_needed(exec_ctx, elem, calld->recv_initial_metadata->deadline); + // Invoke the next callback. + calld->next_recv_initial_metadata_ready->cb( + exec_ctx, calld->next_recv_initial_metadata_ready->cb_arg, error); +} + +// Method for starting a call op for server filter. +static void server_start_transport_stream_op(grpc_exec_ctx* exec_ctx, + grpc_call_element* elem, + grpc_transport_stream_op* op) { + server_call_data* calld = elem->call_data; + if (op->cancel_error != GRPC_ERROR_NONE || + op->close_error != GRPC_ERROR_NONE) { + cancel_timer_if_needed(exec_ctx, &calld->base.deadline_state); + } else { + // If we're receiving initial metadata, we need to get the deadline + // from the recv_initial_metadata_ready callback. So we inject our + // own callback into that hook. + if (op->recv_initial_metadata_ready != NULL) { + calld->next_recv_initial_metadata_ready = op->recv_initial_metadata_ready; + calld->recv_initial_metadata = op->recv_initial_metadata; + grpc_closure_init(&calld->recv_initial_metadata_ready, + recv_initial_metadata_ready, elem); + op->recv_initial_metadata_ready = &calld->recv_initial_metadata_ready; + } + // Make sure we know when the call is complete, so that we can cancel + // the timer. + // Note that we trigger this on recv_trailing_metadata, even though + // the client never sends trailing metadata, because this is the + // hook that tells us when the call is complete on the server side. + if (op->recv_trailing_metadata != NULL) { + inject_on_complete_cb(&calld->base.deadline_state, op); + } + } + // Chain to next filter. + grpc_call_next_op(exec_ctx, elem, op); +} + +const grpc_channel_filter grpc_client_deadline_filter = { + client_start_transport_stream_op, + grpc_channel_next_op, + sizeof(base_call_data), + init_call_elem, + grpc_call_stack_ignore_set_pollset_or_pollset_set, + destroy_call_elem, + 0, // sizeof(channel_data) + init_channel_elem, + destroy_channel_elem, + grpc_call_next_get_peer, + "deadline", +}; + +const grpc_channel_filter grpc_server_deadline_filter = { + server_start_transport_stream_op, + grpc_channel_next_op, + sizeof(server_call_data), + init_call_elem, + grpc_call_stack_ignore_set_pollset_or_pollset_set, + destroy_call_elem, + 0, // sizeof(channel_data) + init_channel_elem, + destroy_channel_elem, + grpc_call_next_get_peer, + "deadline", +}; |