| /* Copyright (C) 2009-2021 Free Software Foundation, Inc. |
| Contributed by Richard Henderson <rth@redhat.com>. |
| |
| This file is part of the GNU Transactional Memory Library (libitm). |
| |
| Libitm 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 3 of the License, or |
| (at your option) any later version. |
| |
| Libitm 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. |
| |
| Under Section 7 of GPL version 3, you are granted additional |
| permissions described in the GCC Runtime Library Exception, version |
| 3.1, as published by the Free Software Foundation. |
| |
| You should have received a copy of the GNU General Public License and |
| a copy of the GCC Runtime Library Exception along with this program; |
| see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include "libitm_i.h" |
| |
| namespace GTM HIDDEN { |
| |
| void |
| gtm_thread::record_allocation (void *ptr, void (*free_fn)(void *)) |
| { |
| // We do not deallocate before outermost commit, so we should never have |
| // an existing log entry for a new allocation. |
| gtm_alloc_action *a = this->alloc_actions.insert((uintptr_t) ptr); |
| |
| a->free_fn = free_fn; |
| a->free_fn_sz = 0; |
| a->allocated = true; |
| } |
| |
| void |
| gtm_thread::forget_allocation (void *ptr, void (*free_fn)(void *)) |
| { |
| // We do not deallocate before outermost commit, so we should never have |
| // an existing log entry for a deallocation at the same address. We may |
| // have an existing entry for a matching allocation, but this is handled |
| // correctly because both are complementary in that only one of these will |
| // cause an action at commit or abort. |
| gtm_alloc_action *a = this->alloc_actions.insert((uintptr_t) ptr); |
| a->free_fn = free_fn; |
| a->free_fn_sz = 0; |
| a->allocated = false; |
| } |
| |
| void |
| gtm_thread::forget_allocation (void *ptr, size_t sz, |
| void (*free_fn_sz)(void *, size_t)) |
| { |
| // Same as forget_allocation but with a size. |
| gtm_alloc_action *a = this->alloc_actions.insert((uintptr_t) ptr); |
| a->free_fn = 0; |
| a->free_fn_sz = free_fn_sz; |
| a->sz = sz; |
| a->allocated = false; |
| } |
| |
| namespace { |
| struct commit_cb_data { |
| aa_tree<uintptr_t, gtm_alloc_action>* parent; |
| bool revert_p; |
| }; |
| } |
| |
| static void |
| commit_allocations_2 (uintptr_t key, gtm_alloc_action *a, void *data) |
| { |
| void *ptr = (void *)key; |
| commit_cb_data *cb_data = static_cast<commit_cb_data *>(data); |
| |
| if (cb_data->revert_p) |
| { |
| // Roll back nested allocations, discard deallocations. |
| if (a->allocated) |
| { |
| if (a->free_fn_sz != 0) |
| a->free_fn_sz (ptr, a->sz); |
| else |
| a->free_fn (ptr); |
| } |
| } |
| else |
| { |
| // Add allocations and deallocations to parent. |
| // ??? We could eliminate a (parent) allocation that matches this |
| // a deallocation, if we had support for removing all accesses |
| // to this allocation from the transaction's undo and redo logs |
| // (otherwise, the parent transaction's undo or redo might write to |
| // data that is already shared again because of calling free()). |
| // We don't have this support currently, and the benefit of this |
| // optimization is unknown, so just add it to the parent. |
| gtm_alloc_action* a_parent = cb_data->parent->insert(key); |
| *a_parent = *a; |
| } |
| } |
| |
| static void |
| commit_allocations_1 (uintptr_t key, gtm_alloc_action *a, void *cb_data) |
| { |
| void *ptr = (void *)key; |
| bool revert_p = (bool) (uintptr_t) cb_data; |
| |
| if (revert_p == a->allocated) |
| { |
| if (a->free_fn_sz != 0) |
| a->free_fn_sz (ptr, a->sz); |
| else |
| a->free_fn (ptr); |
| } |
| } |
| |
| /* Permanently commit allocated memory during transaction. |
| |
| REVERT_P is true if instead of committing the allocations, we want |
| to roll them back (and vice versa). */ |
| void |
| gtm_thread::commit_allocations (bool revert_p, |
| aa_tree<uintptr_t, gtm_alloc_action>* parent) |
| { |
| if (parent) |
| { |
| commit_cb_data cb_data; |
| cb_data.parent = parent; |
| cb_data.revert_p = revert_p; |
| this->alloc_actions.traverse (commit_allocations_2, &cb_data); |
| } |
| else |
| this->alloc_actions.traverse (commit_allocations_1, |
| (void *)(uintptr_t)revert_p); |
| this->alloc_actions.clear (); |
| } |
| |
| } // namespace GTM |