i#5505 kernel trace: Upgrade dr$sim to record syscall's kernel PT

[dolanzhao]

Updates drpt2ir and drpttracer and adds a new module syscall_pt_trace that provides an API for syscall's kernel PT tracing:

(1) Updates drpttracer extension. Replaces the drpttracer_start_tracing() and drpttracer_end_tracing() with drpttracer_create_tracer(), drpttracer_destory_tracer(), drpttracer_start_tracing() and drpttracer_end_tracing(). In the original implementation, the client will get a tracer by calling drpttracer_start_tracing() and destroy the tracer when calling drpttracer_end_tracing(). If the client traces multiple times, the tracer's creation and destruction will cause a big overhead. Currently, the client can use drpttracer_create_tracer() to get a tracer and use drpttracer_start_tracing() and drpttracer_end_tracing() to start and stop a tracing processes, then use drpttracer_destory_tracer() to destroy the tracer. In the future implementation, multiple traces can share one tracer, and the overhead is reduced to an acceptable level.

(2) Adds the syscall_pt_ trace module for dr$sim to record syscall's kernel PT trace. This module wraps a P tracer as a class and provides APIs for thread-local syscall tracing. Also, it provides APIs to check the currently tracing syscall's sysnum and last recorded syscall's id. In this PR, syscall_pt_trace will create a trace handle for each syscall, making the decoding process simple for the decoder.

(3) Updates dr$sim to support kernel tracing. In the current implementation, every monitored thread will create a tracer during the thread start, and dr$sim will start the syscall kernel tracing in the pre-syscall callback and stop the syscall kernel tracing at post-syscall callbacks. And every syscall will dump the PT data and metadata to files. Also, before the process end, dr$sim will use the 'perf record --kcore' command to copy out kcore and kallsyms used in the PT post processer.

(4) Updates drpt2ir. The current implementation supports using the metadata file to initiate an instance of pt2ir_config_t and replaces some c pointer parameters with c++ reference parameters.

(5) Updates drpt2trace. Adds a new option to support directly reading metadata files to initialize pt2ir_config_t. In the current implementation, drpt2trace will first use a metadata file to init the instance of pt2ir_config_t. Then if the user specifies some options, it will overwrite the corresponding field in the instance of pt2ir_config_t.

(6) Add a new test for dr$sim to check that the kernel PT output is correct. Defines a new macro for kernel feature check and adds a simple test for dr$sim. The macro will run dr$sim to generate kernel PT and drpt2trace to check whether the generated kernel PT can be decoded.

Issue: #5505