ardour/libs/pbd/pool.cc
Robin Gareus 25d1209bb4
Only dump SessionEvent pool in debug builds
This ensures that the user will see a "POOL OUT OF MEMORY" message.
In rare case dumping the pool can segfault when printing the Event,
The pool is zero initialized and only ever contains events, so
in theory it is safe to print them..
2022-07-07 22:34:11 +02:00

308 lines
7.8 KiB
C++

/*
* Copyright (C) 2006 Taybin Rutkin <taybin@taybin.com>
* Copyright (C) 2008-2009 David Robillard <d@drobilla.net>
* Copyright (C) 2008-2011 Carl Hetherington <carl@carlh.net>
* Copyright (C) 1998-2015 Paul Davis <paul@linuxaudiosystems.com>
* Copyright (C) 2014-2022 Robin Gareus <robin@gareus.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <cassert>
#include <cstdio>
#include <cstdlib>
#include <vector>
#include "pbd/compose.h"
#include "pbd/debug.h"
#include "pbd/error.h"
#include "pbd/pool.h"
#include "pbd/pthread_utils.h"
#include "pbd/stacktrace.h"
using namespace std;
using namespace PBD;
Pool::Pool (string n, unsigned long item_size, unsigned long nitems, PoolDumpCallback cb)
: free_list (nitems)
, _name (n)
, _dump (cb)
#ifndef NDEBUG
, max_usage (0)
#endif
{
_name = n;
/* adjust to actual size (power-of-two) */
nitems = free_list.bufsize ();
/* since some overloaded ::operator new() might use this,
its important that we use a "lower level" allocator to
get more space.
*/
_block = malloc (nitems * item_size);
void** ptrlist = (void**)calloc (nitems, sizeof (void*));
for (unsigned long i = 0; i < nitems; i++) {
ptrlist[i] = static_cast<void*> (static_cast<char*> (_block) + (i * item_size));
}
free_list.write (ptrlist, nitems);
free (ptrlist);
}
Pool::~Pool ()
{
DEBUG_TRACE (DEBUG::Pool, string_compose ("Pool: '%1' max: %2 / %3\n", name (), max_usage, total ()));
free (_block);
}
/** Allocate an item's worth of memory in the Pool by taking one from the free list.
* @return Pointer to free item.
*/
void*
Pool::alloc ()
{
void* ptr;
#ifndef NDEBUG
if (used () > max_usage) {
max_usage = used () + 1;
}
#endif
if (free_list.read (&ptr, 1) < 1) {
PBD::stacktrace (std::cerr, 20);
if (_dump) {
printf ("RingBuffer write-idx: %u read-idx: %u\n", free_list.get_write_idx (), free_list.get_read_idx ());
void** _block = free_list.buffer ();
for (size_t i = 0; i < free_list.bufsize (); ++i) {
_dump (i, _block[i]);
}
}
fatal << "CRITICAL: " << _name << " POOL OUT OF MEMORY - RECOMPILE WITH LARGER SIZE!!" << endmsg;
abort (); /*NOTREACHED*/
return 0;
} else {
return ptr;
}
}
/** Release an item's memory by writing its location to the free list */
void
Pool::release (void* ptr)
{
free_list.write (&ptr, 1);
}
/*---------------------------------------------*/
MultiAllocSingleReleasePool::MultiAllocSingleReleasePool (string n, unsigned long isize, unsigned long nitems)
: Pool (n, isize, nitems)
{
}
MultiAllocSingleReleasePool::~MultiAllocSingleReleasePool ()
{
}
SingleAllocMultiReleasePool::SingleAllocMultiReleasePool (string n, unsigned long isize, unsigned long nitems)
: Pool (n, isize, nitems)
{
}
SingleAllocMultiReleasePool::~SingleAllocMultiReleasePool ()
{
}
void*
MultiAllocSingleReleasePool::alloc ()
{
Glib::Threads::Mutex::Lock guard (m_lock);
return Pool::alloc ();
}
void
MultiAllocSingleReleasePool::release (void* ptr)
{
Pool::release (ptr);
}
void*
SingleAllocMultiReleasePool::alloc ()
{
return Pool::alloc ();
}
void
SingleAllocMultiReleasePool::release (void* ptr)
{
Glib::Threads::Mutex::Lock guard (m_lock);
Pool::release (ptr);
}
/*-------------------------------------------------------*/
static void
free_per_thread_pool (void* ptr)
{
/* Rather than deleting the CrossThreadPool now, we add it to our trash buffer.
* This prevents problems if other threads still require access to this CrossThreadPool.
* We assume that some other agent will clean out the trash buffer as required.
*/
CrossThreadPool* cp = static_cast<CrossThreadPool*> (ptr);
assert (cp);
if (cp->empty ()) {
/* This CrossThreadPool is already empty, and the thread is finishing so nothing
* more can be added to it. We can just delete the pool.
*/
delete cp;
} else {
/* This CrossThreadPool is not empty, meaning that there's some Events in it
* which another thread may yet read, so we can't delete the pool just yet.
* Put it in the trash and hope someone deals with it at some stage.
*/
cp->parent ()->add_to_trash (cp);
}
}
PerThreadPool::PerThreadPool ()
: _key (free_per_thread_pool)
, _trash (0)
{
}
/** Create a new CrossThreadPool and set the current thread's private _key to point to it.
* @param n Name.
* @param isize Size of each item in the pool.
* @param nitems Number of items in the pool.
*/
void
PerThreadPool::create_per_thread_pool (string n, unsigned long isize, unsigned long nitems, PoolDumpCallback cb)
{
_key.set (new CrossThreadPool (n, isize, nitems, this, cb));
}
/** @return True if CrossThreadPool for the current thread exists,
* False otherwise
*/
bool
PerThreadPool::has_per_thread_pool ()
{
CrossThreadPool* p = _key.get ();
if (p) {
return true;
}
return false;
}
/** @return CrossThreadPool for the current thread, which must previously have been created by
* calling create_per_thread_pool in the current thread.
*/
CrossThreadPool*
PerThreadPool::per_thread_pool (bool must_exist)
{
CrossThreadPool* p = _key.get ();
if (!p && must_exist) {
fatal << "programming error: no per-thread pool \"" << _name << "\" for thread " << pthread_name () << endmsg;
abort (); /*NOTREACHED*/
}
return p;
}
void
PerThreadPool::set_trash (RingBuffer<CrossThreadPool*>* t)
{
Glib::Threads::Mutex::Lock lm (_trash_mutex);
_trash = t;
}
/** Add a CrossThreadPool to our trash, if we have one. If not, a warning is emitted. */
void
PerThreadPool::add_to_trash (CrossThreadPool* p)
{
Glib::Threads::Mutex::Lock lm (_trash_mutex);
if (!_trash) {
warning << "Pool " << p->name () << " has no trash collector; a memory leak has therefore occurred" << endmsg;
return;
}
/* we have a lock here so that multiple threads can safely call add_to_trash (even though there
can only be one writer to the _trash RingBuffer)
*/
_trash->write (&p, 1);
}
CrossThreadPool::CrossThreadPool (string n, unsigned long isize, unsigned long nitems, PerThreadPool* p, PoolDumpCallback cb)
: Pool (n, isize, nitems, cb)
, pending (nitems)
, _parent (p)
{
}
void
CrossThreadPool::flush_pending_with_ev (void* ptr)
{
push (ptr);
flush_pending ();
}
void
CrossThreadPool::flush_pending ()
{
void* ptr;
bool did_release = false;
DEBUG_TRACE (DEBUG::Pool, string_compose ("%1 %2 has %3 pending free entries waiting, status size %4 free %5 used %6\n", pthread_name (), name (), pending.read_space (),
total (), available (), used ()));
while (pending.read (&ptr, 1) == 1) {
DEBUG_TRACE (DEBUG::Pool, string_compose ("%1 %2 pushes back a pending free list entry before allocating\n", pthread_name (), name ()));
free_list.write (&ptr, 1);
did_release = true;
}
if (did_release) {
DEBUG_TRACE (DEBUG::Pool, string_compose ("Pool size: %1 free %2 used %3 pending now %4\n", total (), available (), used (), pending_size ()));
}
}
void*
CrossThreadPool::alloc ()
{
/* process anything waiting to be deleted (i.e. moved back to the free list) */
flush_pending ();
/* now allocate from the potentially larger free list */
return Pool::alloc ();
}
void
CrossThreadPool::push (void* t)
{
pending.write (&t, 1);
}
/** @return true if there is nothing in this pool */
bool
CrossThreadPool::empty ()
{
return (free_list.write_space () == pending.read_space ());
}