RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-28 07:07:44 +00:00
Code Issues Activity Actions

Kernel: Add syscall performance event type

Browse source 
This allows tracing the syscalls made by a thread through the kernel's
performance event framework, which is similar in principle to strace.

Currently, this merely logs a stack backtrace to the current thread's
performance event buffer whenever a syscall is made, if profiling is
enabled. Future improvements could include tracing the arguments and
the return value, for example.
This commit is contained in:
Jean-Baptiste Boric 2021-08-10 21:02:59 +02:00 • committed by Andreas Kling
parent 4c4b8ea443
commit 0286160b62
6 changed files with 24 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

5
Kernel/PerformanceEventBuffer.cpp
View file

@ -135,6 +135,8 @@ KResult PerformanceEventBuffer::append_with_ip_and_bp(ProcessID pid, ThreadID ti
break;
case PERF_EVENT_PAGE_FAULT:
break;
case PERF_EVENT_SYSCALL:
break;
default:
return EINVAL;
}
@ -226,6 +228,9 @@ bool PerformanceEventBuffer::to_json_impl(Serializer& object) const
case PERF_EVENT_PAGE_FAULT:
event_object.add("type", "page_fault");
break;
case PERF_EVENT_SYSCALL:
event_object.add("type", "syscall");
break;
}
event_object.add("pid", event.pid);
event_object.add("tid", event.tid);

11
Kernel/PerformanceManager.h
View file

@ -119,6 +119,17 @@ public:
}
}
inline static void add_syscall_event(Thread& thread, const RegisterState& regs)
{
if (thread.is_profiling_suppressed())
return;
if (auto* event_buffer = thread.process().current_perf_events_buffer()) {
[[maybe_unused]] auto rc = event_buffer->append_with_ip_and_bp(
thread.pid(), thread.tid(),
regs.ip(), regs.bp(), PERF_EVENT_SYSCALL, 0, 0, 0, nullptr);
}
}
inline static void timer_tick(RegisterState const& regs)
{
static Time last_wakeup;

3
Kernel/Syscall.cpp
View file

@ -9,6 +9,7 @@
#include <Kernel/Arch/x86/TrapFrame.h>
#include <Kernel/Memory/MemoryManager.h>
#include <Kernel/Panic.h>
#include <Kernel/PerformanceManager.h>
#include <Kernel/Process.h>
#include <Kernel/Sections.h>
#include <Kernel/ThreadTracer.h>
@ -108,6 +109,8 @@ KResultOr<FlatPtr> handle(RegisterState& regs, FlatPtr function, FlatPtr arg1, F
auto& process = current_thread->process();
current_thread->did_syscall();
PerformanceManager::add_syscall_event(*current_thread, regs);
if (function >= Function::__Count) {
dbgln("Unknown syscall {} requested ({:p}, {:p}, {:p}, {:p})", function, arg1, arg2, arg3, arg4);
return ENOSYS;

1
Kernel/UnixTypes.h
View file

@ -62,6 +62,7 @@ enum {
PERF_EVENT_KMALLOC = 2048,
PERF_EVENT_KFREE = 4096,
PERF_EVENT_PAGE_FAULT = 8192,
PERF_EVENT_SYSCALL = 16384,
};
#define WNOHANG 1