diff options
Diffstat (limited to 'src/core/lib/channel/channel_trace.h')
-rw-r--r-- | src/core/lib/channel/channel_trace.h | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/src/core/lib/channel/channel_trace.h b/src/core/lib/channel/channel_trace.h new file mode 100644 index 0000000000..1df1e585f2 --- /dev/null +++ b/src/core/lib/channel/channel_trace.h @@ -0,0 +1,133 @@ +/* + * + * Copyright 2017 gRPC authors. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + */ + +#ifndef GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_H +#define GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_H + +#include <grpc/impl/codegen/port_platform.h> + +#include <grpc/grpc.h> +#include "src/core/lib/gprpp/ref_counted.h" +#include "src/core/lib/gprpp/ref_counted_ptr.h" +#include "src/core/lib/iomgr/error.h" +#include "src/core/lib/json/json.h" + +namespace grpc_core { + +// Object used to hold live data for a channel. This data is exposed via the +// channelz service: +// https://github.com/grpc/proposal/blob/master/A14-channelz.md +class ChannelTrace : public RefCounted<ChannelTrace> { + public: + ChannelTrace(size_t max_events); + ~ChannelTrace(); + + // returns the tracer's uuid + intptr_t GetUuid() const; + + enum Severity { + Unset = 0, // never to be used + Info, // we start at 1 to avoid using proto default values + Warning, + Error + }; + + // Adds a new trace event to the tracing object + // + // TODO(ncteisen): as this call is used more and more throughout the gRPC + // stack, determine if it makes more sense to accept a char* instead of a + // slice. + void AddTraceEvent(Severity severity, grpc_slice data); + + // Adds a new trace event to the tracing object. This trace event refers to a + // an event on a child of the channel. For example, if this channel has + // created a new subchannel, then it would record that with a TraceEvent + // referencing the new subchannel. + // + // TODO(ncteisen): Once channelz is implemented, the events should reference + // the overall channelz object, not just the ChannelTrace object. + // TODO(ncteisen): as this call is used more and more throughout the gRPC + // stack, determine if it makes more sense to accept a char* instead of a + // slice. + void AddTraceEventReferencingChannel( + Severity severity, grpc_slice data, + RefCountedPtr<ChannelTrace> referenced_tracer); + void AddTraceEventReferencingSubchannel( + Severity severity, grpc_slice data, + RefCountedPtr<ChannelTrace> referenced_tracer); + + // Returns the tracing data rendered as a grpc json string. + // The string is owned by the caller and must be freed. + char* RenderTrace() const; + + private: + // Types of objects that can be references by trace events. + enum ReferencedType { Channel, Subchannel }; + // Private class to encapsulate all the data and bookkeeping needed for a + // a trace event. + class TraceEvent { + public: + // Constructor for a TraceEvent that references a different channel. + // TODO(ncteisen): once channelz is implemented, this should reference the + // overall channelz object, not just the ChannelTrace object + TraceEvent(Severity severity, grpc_slice data, + RefCountedPtr<ChannelTrace> referenced_tracer, + ReferencedType type); + + // Constructor for a TraceEvent that does not reverence a different + // channel. + TraceEvent(Severity severity, grpc_slice data); + + ~TraceEvent(); + + // Renders the data inside of this TraceEvent into a json object. This is + // used by the ChannelTrace, when it is rendering itself. + void RenderTraceEvent(grpc_json* json) const; + + // set and get for the next_ pointer. + TraceEvent* next() const { return next_; } + void set_next(TraceEvent* next) { next_ = next; } + + private: + Severity severity_; + grpc_slice data_; + gpr_timespec timestamp_; + TraceEvent* next_; + // the tracer object for the (sub)channel that this trace event refers to. + RefCountedPtr<ChannelTrace> referenced_tracer_; + // the type that the referenced tracer points to. Unused if this trace + // does not point to any channel or subchannel + ReferencedType referenced_type_; + }; // TraceEvent + + // Internal helper to add and link in a trace event + void AddTraceEventHelper(TraceEvent* new_trace_event); + + gpr_mu tracer_mu_; + intptr_t channel_uuid_; + uint64_t num_events_logged_; + size_t list_size_; + size_t max_list_size_; + TraceEvent* head_trace_; + TraceEvent* tail_trace_; + gpr_timespec time_created_; +}; + +} // namespace grpc_core + +#endif /* GRPC_CORE_LIB_CHANNEL_CHANNEL_TRACE_H */ |