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Peter Anvin" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 20, 2021 at 8:47 PM Michael Roth wrote: > > On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote: > > On Tue, Oct 5, 2021 at 4:46 PM Michael Roth wrote: > > > > > > Subsequent patches will break some of this code out into file-local > > > helper functions, which will be used by functions like vm_vaddr_alloc(), > > > which currently are defined earlier in the file, so a forward > > > declaration would be needed. > > > > > > Instead, move it earlier in the file, just above vm_vaddr_alloc() and > > > and friends, which are the main users. > > > > > > Signed-off-by: Michael Roth > > > --- > > > tools/testing/selftests/kvm/lib/kvm_util.c | 146 ++++++++++----------- > > > 1 file changed, 73 insertions(+), 73 deletions(-) > > > > > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c > > > index 10a8ed691c66..92f59adddebe 100644 > > > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > > > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > > > @@ -1145,6 +1145,79 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid) > > > list_add(&vcpu->list, &vm->vcpus); > > > } > > > > > > +/* > > > + * Physical Contiguous Page Allocator > > > + * > > > + * Input Args: > > > + * vm - Virtual Machine > > > + * num - number of pages > > > + * paddr_min - Physical address minimum > > > + * memslot - Memory region to allocate page from > > > + * > > > + * Output Args: None > > > + * > > > + * Return: > > > + * Starting physical address > > > + * > > > + * Within the VM specified by vm, locates a range of available physical > > > + * pages at or above paddr_min. If found, the pages are marked as in use > > > + * and their base address is returned. A TEST_ASSERT failure occurs if > > > + * not enough pages are available at or above paddr_min. > > > + */ > > > +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num, > > > + vm_paddr_t paddr_min, uint32_t memslot) > > > +{ > > > + struct userspace_mem_region *region; > > > + sparsebit_idx_t pg, base; > > > + > > > + TEST_ASSERT(num > 0, "Must allocate at least one page"); > > > + > > > + TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address " > > > + "not divisible by page size.\n" > > > + " paddr_min: 0x%lx page_size: 0x%x", > > > + paddr_min, vm->page_size); > > > + > > > + region = memslot2region(vm, memslot); > > > + base = pg = paddr_min >> vm->page_shift; > > > + > > > + do { > > > + for (; pg < base + num; ++pg) { > > > + if (!sparsebit_is_set(region->unused_phy_pages, pg)) { > > > + base = pg = sparsebit_next_set(region->unused_phy_pages, pg); > > > + break; > > > + } > > > + } > > > + } while (pg && pg != base + num); > > > + > > > + if (pg == 0) { > > > + fprintf(stderr, "No guest physical page available, " > > > + "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n", > > > + paddr_min, vm->page_size, memslot); > > > + fputs("---- vm dump ----\n", stderr); > > > + vm_dump(stderr, vm, 2); > > > + abort(); > > > + } > > > + > > > + for (pg = base; pg < base + num; ++pg) > > > + sparsebit_clear(region->unused_phy_pages, pg); > > > + > > > + return base * vm->page_size; > > > +} > > > + > > > +vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min, > > > + uint32_t memslot) > > > +{ > > > + return vm_phy_pages_alloc(vm, 1, paddr_min, memslot); > > > +} > > > + > > > +/* Arbitrary minimum physical address used for virtual translation tables. */ > > > +#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000 > > > + > > > +vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm) > > > +{ > > > + return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0); > > > +} > > > + > > > /* > > > * VM Virtual Address Unused Gap > > > * > > > @@ -2149,79 +2222,6 @@ const char *exit_reason_str(unsigned int exit_reason) > > > return "Unknown"; > > > } > > > > > > -/* > > > - * Physical Contiguous Page Allocator > > > - * > > > - * Input Args: > > > - * vm - Virtual Machine > > > - * num - number of pages > > > - * paddr_min - Physical address minimum > > > - * memslot - Memory region to allocate page from > > > - * > > > - * Output Args: None > > > - * > > > - * Return: > > > - * Starting physical address > > > - * > > > - * Within the VM specified by vm, locates a range of available physical > > > - * pages at or above paddr_min. If found, the pages are marked as in use > > > - * and their base address is returned. A TEST_ASSERT failure occurs if > > > - * not enough pages are available at or above paddr_min. > > > - */ > > > -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num, > > > - vm_paddr_t paddr_min, uint32_t memslot) > > > -{ > > > - struct userspace_mem_region *region; > > > - sparsebit_idx_t pg, base; > > > - > > > - TEST_ASSERT(num > 0, "Must allocate at least one page"); > > > - > > > - TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address " > > > - "not divisible by page size.\n" > > > - " paddr_min: 0x%lx page_size: 0x%x", > > > - paddr_min, vm->page_size); > > > - > > > - region = memslot2region(vm, memslot); > > > - base = pg = paddr_min >> vm->page_shift; > > > - > > > - do { > > > - for (; pg < base + num; ++pg) { > > > - if (!sparsebit_is_set(region->unused_phy_pages, pg)) { > > > - base = pg = sparsebit_next_set(region->unused_phy_pages, pg); > > > - break; > > > - } > > > - } > > > - } while (pg && pg != base + num); > > > - > > > - if (pg == 0) { > > > - fprintf(stderr, "No guest physical page available, " > > > - "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n", > > > - paddr_min, vm->page_size, memslot); > > > - fputs("---- vm dump ----\n", stderr); > > > - vm_dump(stderr, vm, 2); > > > - abort(); > > > - } > > > - > > > - for (pg = base; pg < base + num; ++pg) > > > - sparsebit_clear(region->unused_phy_pages, pg); > > > - > > > - return base * vm->page_size; > > > -} > > > - > > > -vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min, > > > - uint32_t memslot) > > > -{ > > > - return vm_phy_pages_alloc(vm, 1, paddr_min, memslot); > > > -} > > > - > > > -/* Arbitrary minimum physical address used for virtual translation tables. */ > > > -#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000 > > > - > > > -vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm) > > > -{ > > > - return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0); > > > -} > > > - > > > /* > > > * Address Guest Virtual to Host Virtual > > > * > > > -- > > > 2.25.1 > > > > > > > Why move the function implementation? Maybe just adding a declaration > > at the top of kvm_util.c should suffice. > > At least from working on other projects I'd gotten the impression that > forward function declarations should be avoided if they can be solved by > moving the function above the caller. Certainly don't mind taking your > suggestion and dropping this patch if that's not the case here though. Understood. Yes, I think it would be better to follow your experience then. I was thinking that if you move the code and then potentially git blame on that function might point to you :) Thanks. -Mingwei