factor/vm/sampling_profiler.cpp

144 lines
5.0 KiB
C++

#include "master.hpp"
namespace factor {
profiling_sample_count profiling_sample_count::record_counts() volatile {
atomic::fence();
profiling_sample_count returned(sample_count, gc_sample_count,
jit_sample_count, foreign_sample_count,
foreign_thread_sample_count);
atomic::fetch_subtract(&sample_count, returned.sample_count);
atomic::fetch_subtract(&gc_sample_count, returned.gc_sample_count);
atomic::fetch_subtract(&jit_sample_count, returned.jit_sample_count);
atomic::fetch_subtract(&foreign_sample_count, returned.foreign_sample_count);
atomic::fetch_subtract(&foreign_thread_sample_count,
returned.foreign_thread_sample_count);
return returned;
}
void profiling_sample_count::clear() volatile {
sample_count = 0;
gc_sample_count = 0;
jit_sample_count = 0;
foreign_sample_count = 0;
foreign_thread_sample_count = 0;
atomic::fence();
}
profiling_sample::profiling_sample(profiling_sample_count const& counts, cell thread,
cell callstack_begin, cell callstack_end)
: counts(counts), thread(thread),
callstack_begin(callstack_begin),
callstack_end(callstack_end) { }
void factor_vm::record_sample(bool prolog_p) {
profiling_sample_count counts = sample_counts.record_counts();
if (counts.empty()) {
return;
}
// Appends the callstack, which is just a sequence of quotation or
// word references, to sample_callstacks.
cell begin = sample_callstacks.size();
bool skip_p = prolog_p;
auto recorder = [&](cell frame_top, cell size, code_block* owner, cell addr) {
if (skip_p)
skip_p = false;
else
sample_callstacks.push_back(owner->owner);
};
iterate_callstack(ctx, recorder);
cell end = sample_callstacks.size();
// Add the sample.
cell thread = special_objects[OBJ_CURRENT_THREAD];
samples.push_back(profiling_sample(counts, thread, begin, end));
}
void factor_vm::set_sampling_profiler(fixnum rate) {
bool running_p = (atomic::load(&sampling_profiler_p) != 0);
if (rate > 0 && !running_p)
start_sampling_profiler(rate);
else if (rate == 0 && running_p)
end_sampling_profiler();
}
void factor_vm::start_sampling_profiler(fixnum rate) {
samples_per_second = rate;
sample_counts.clear();
// Release the memory consumed by collecting samples.
samples.clear();
samples.shrink_to_fit();
sample_callstacks.clear();
sample_callstacks.shrink_to_fit();
samples.reserve(10 * rate);
sample_callstacks.reserve(100 * rate);
atomic::store(&sampling_profiler_p, true);
start_sampling_profiler_timer();
}
void factor_vm::end_sampling_profiler() {
atomic::store(&sampling_profiler_p, false);
end_sampling_profiler_timer();
record_sample(false);
}
void factor_vm::primitive_sampling_profiler() {
set_sampling_profiler(to_fixnum(ctx->pop()));
}
// Allocates memory
void factor_vm::primitive_get_samples() {
if (atomic::load(&sampling_profiler_p) || samples.empty()) {
ctx->push(false_object);
} else {
data_root<array> samples_array(allot_array(samples.size(), false_object),
this);
std::vector<profiling_sample>::const_iterator from_iter = samples.begin();
cell to_i = 0;
for (; from_iter != samples.end(); ++from_iter, ++to_i) {
data_root<array> sample(allot_array(7, false_object), this);
set_array_nth(sample.untagged(), 0,
tag_fixnum(from_iter->counts.sample_count));
set_array_nth(sample.untagged(), 1,
tag_fixnum(from_iter->counts.gc_sample_count));
set_array_nth(sample.untagged(), 2,
tag_fixnum(from_iter->counts.jit_sample_count));
set_array_nth(sample.untagged(), 3,
tag_fixnum(from_iter->counts.foreign_sample_count));
set_array_nth(sample.untagged(), 4,
tag_fixnum(from_iter->counts.foreign_thread_sample_count));
set_array_nth(sample.untagged(), 5, from_iter->thread);
cell callstack_size =
from_iter->callstack_end - from_iter->callstack_begin;
data_root<array> callstack(allot_array(callstack_size, false_object),
this);
std::vector<cell>::const_iterator callstacks_begin =
sample_callstacks.begin(),
c_from_iter =
callstacks_begin +
from_iter->callstack_begin,
c_from_iter_end =
callstacks_begin +
from_iter->callstack_end;
cell c_to_i = 0;
for (; c_from_iter != c_from_iter_end; ++c_from_iter, ++c_to_i)
set_array_nth(callstack.untagged(), c_to_i, *c_from_iter);
set_array_nth(sample.untagged(), 6, callstack.value());
set_array_nth(samples_array.untagged(), to_i, sample.value());
}
ctx->push(samples_array.value());
}
}
}