ladybird/Kernel/Syscalls/profiling.cpp
Jean-Baptiste Boric 08891e82a5 Kernel: Migrate process list locking to ProtectedValue
The existing recursive spinlock is repurposed for profiling only, as it
was shared with the process list.
2021-08-07 11:48:00 +02:00

132 lines
3.7 KiB
C++

/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/CoreDump.h>
#include <Kernel/FileSystem/VirtualFileSystem.h>
#include <Kernel/PerformanceManager.h>
#include <Kernel/Process.h>
#include <Kernel/Time/TimeManagement.h>
namespace Kernel {
bool g_profiling_all_threads;
PerformanceEventBuffer* g_global_perf_events;
u64 g_profiling_event_mask;
KResultOr<FlatPtr> Process::sys$profiling_enable(pid_t pid, u64 event_mask)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_NO_PROMISES;
if (pid == -1) {
if (!is_superuser())
return EPERM;
ScopedCritical critical;
g_profiling_event_mask = PERF_EVENT_PROCESS_CREATE | PERF_EVENT_THREAD_CREATE | PERF_EVENT_MMAP;
if (g_global_perf_events)
g_global_perf_events->clear();
else
g_global_perf_events = PerformanceEventBuffer::try_create_with_size(32 * MiB).leak_ptr();
ScopedSpinLock lock(g_profiling_lock);
if (!TimeManagement::the().enable_profile_timer())
return ENOTSUP;
g_profiling_all_threads = true;
PerformanceManager::add_process_created_event(*Scheduler::colonel());
Process::for_each([](auto& process) {
PerformanceManager::add_process_created_event(process);
return IterationDecision::Continue;
});
g_profiling_event_mask = event_mask;
return 0;
}
auto process = Process::from_pid(pid);
if (!process)
return ESRCH;
if (process->is_dead())
return ESRCH;
if (!is_superuser() && process->uid() != euid())
return EPERM;
ScopedSpinLock lock(g_profiling_lock);
g_profiling_event_mask = PERF_EVENT_PROCESS_CREATE | PERF_EVENT_THREAD_CREATE | PERF_EVENT_MMAP;
process->set_profiling(true);
if (!process->create_perf_events_buffer_if_needed()) {
process->set_profiling(false);
return ENOMEM;
}
g_profiling_event_mask = event_mask;
if (!TimeManagement::the().enable_profile_timer()) {
process->set_profiling(false);
return ENOTSUP;
}
return 0;
}
KResultOr<FlatPtr> Process::sys$profiling_disable(pid_t pid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_NO_PROMISES;
if (pid == -1) {
if (!is_superuser())
return EPERM;
ScopedCritical critical;
if (!TimeManagement::the().disable_profile_timer())
return ENOTSUP;
g_profiling_all_threads = false;
return 0;
}
auto process = Process::from_pid(pid);
if (!process)
return ESRCH;
if (!is_superuser() && process->uid() != euid())
return EPERM;
ScopedSpinLock lock(g_profiling_lock);
if (!process->is_profiling())
return EINVAL;
// FIXME: If we enabled the profile timer and it's not supported, how do we disable it now?
if (!TimeManagement::the().disable_profile_timer())
return ENOTSUP;
process->set_profiling(false);
return 0;
}
KResultOr<FlatPtr> Process::sys$profiling_free_buffer(pid_t pid)
{
VERIFY_PROCESS_BIG_LOCK_ACQUIRED(this)
REQUIRE_NO_PROMISES;
if (pid == -1) {
if (!is_superuser())
return EPERM;
OwnPtr<PerformanceEventBuffer> perf_events;
{
ScopedCritical critical;
perf_events = adopt_own_if_nonnull(g_global_perf_events);
g_global_perf_events = nullptr;
}
return 0;
}
auto process = Process::from_pid(pid);
if (!process)
return ESRCH;
if (!is_superuser() && process->uid() != euid())
return EPERM;
ScopedSpinLock lock(g_profiling_lock);
if (process->is_profiling())
return EINVAL;
process->delete_perf_events_buffer();
return 0;
}
}