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Pagemap Rounding (#558)

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* Extend pagemap test

Check for possible overlap between heap and pagemap, but writing and
reading the heap.

* Return unalign memory from the pagemap

This commit allows the pagemap to return unaligned range of memory. This
means that bump allocation of multiple pagemaps doesn't
waste as much space.
This commit is contained in:
Matthew Parkinson
2022-09-17 14:30:13 +01:00
committed by GitHub
parent 15e5a842f5
commit 2f8f376db8
2 changed files with 68 additions and 23 deletions
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34
src/test/func/pagemap/pagemap.cc
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@@ -56,7 +56,8 @@ void set(bool bounded, address_t address, T new_value)
void test_pagemap(bool bounded)
{
address_t low = bits::one_at_bit(23);
address_t high = bits::one_at_bit(30);
address_t high = bits::one_at_bit(29);
void* base = nullptr;
// Nullptr needs to work before initialisation
CHECK_GET(bounded, 0, T());
@@ -64,8 +65,8 @@ void test_pagemap(bool bounded)
// Initialise the pagemap
if (bounded)
{
auto size = bits::one_at_bit(30);
auto base = DefaultPal::reserve(size);
auto size = bits::one_at_bit(29);
base = DefaultPal::reserve(size);
DefaultPal::notify_using<NoZero>(base, size);
std::cout << "Fixed base: " << base << " (" << size << ") "
<< " end: " << pointer_offset(base, size) << std::endl;
@@ -73,7 +74,10 @@ void test_pagemap(bool bounded)
std::cout << "Heap base: " << heap_base << " (" << heap_size << ") "
<< " end: " << pointer_offset(heap_base, heap_size) << std::endl;
low = address_cast(heap_base);
base = heap_base;
high = low + heap_size;
// Store a pattern in heap.
memset(base, 0x23, high - low);
}
else
{
@@ -99,6 +103,30 @@ void test_pagemap(bool bounded)
// Check pattern is correctly stored
std::cout << std::endl;
if (bounded)
{
std::cout << "Checking heap" << std::endl;
// Check we have not corrupted the heap.
for (size_t offset = 0; offset < high - low; offset++)
{
if ((offset % (1ULL << 26)) == 0)
std::cout << "." << std::flush;
auto* p = ((char*)base) + offset;
if (*p != 0x23)
{
printf("Heap and pagemap have collided at %p", p);
abort();
}
}
std::cout << std::endl;
std::cout << "Storing new pattern" << std::endl;
// Store a different pattern in heap.
memset(base, 0x23, high - low);
}
std::cout << "Checking pagemap contents" << std::endl;
value = 1;
for (address_t ptr = low; ptr < high;
ptr += bits::one_at_bit(GRANULARITY_BITS + 3))