slight optimization

3 files changed, 56 insertions, 14 deletions

diff --git a/arch/riscv64/kernel/vmem.c b/arch/riscv64/kernel/vmem.c
index d12015c..68ccbd3 100644
--- a/arch/riscv64/kernel/vmem.c
+++ b/arch/riscv64/kernel/vmem.c
@@ -122,6 +122,38 @@ static pm_t *__find_vmem(struct vmem *b, vm_t v, enum mm_order *o)
 	return 0;
 }
 
+stat_t set_vpage_flags(struct vmem *branch, vm_t vaddr, vmflags_t flags)
+{
+	enum mm_order order;
+	pm_t *pte = __find_vmem(branch, vaddr, &order);
+	if (pte) {
+		set_bits(*pte, vp_flags(flags));
+
+		if (order == __mm_max_order)
+			return INFO_SEFF;
+		else
+			return OK;
+	}
+
+	return ERR_NF;
+}
+
+stat_t clear_vpage_flags(struct vmem *branch, vm_t vaddr, vmflags_t flags)
+{
+	enum mm_order order;
+	pm_t *pte = __find_vmem(branch, vaddr, &order);
+	if (pte) {
+		clear_bits(*pte, vp_flags(flags));
+
+		if (order == __mm_max_order)
+			return INFO_SEFF;
+		else
+			return OK;
+	}
+
+	return ERR_NF;
+}
+
 stat_t mod_vpage(struct vmem *branch, vm_t vaddr, pm_t paddr, vmflags_t flags)
 {
 	enum mm_order order;
@@ -227,7 +259,7 @@ stat_t unmap_vpage(struct vmem *branch, vm_t vaddr)
 
 void flush_tlb()
 {
-	__asm__ volatile ("sfence.vma %0\n" : : "r" (cpu_id()) : "memory");
+	__asm__ volatile ("sfence.vma %0\n" : : "r" (0) : "memory");
 }
 
 void flush_tlb_all()
@@ -256,7 +288,7 @@ static void __use_vmem(struct vmem *branch, enum mm_mode m)
 		mode = SATP_MODE_Sv48;
 
 	csr_write(CSR_SATP, mode | pn);
-	flush_tlb_all();
+	flush_tlb();
 	/* Sv57 && Sv64 in the future? */
 	/** @todo ASID table for maybe faster context switches? */
 }
diff --git a/common/tcb.c b/common/tcb.c
index aa66d3f..daaae4d 100644
--- a/common/tcb.c
+++ b/common/tcb.c
@@ -387,12 +387,8 @@ static void mark_rpc_inaccessible(struct tcb *t, vm_t start, vm_t end)
 	size_t page_size = BASE_PAGE_SIZE;
 	size_t size = end - start;
 	size_t pages = size / page_size;
-	while (pages--) {
-		/** @todo something like mod_vpage_flags could be faster */
-		vmflags_t flags; pm_t paddr;
-		stat_vpage(t->rpc.vmem, start, &paddr, NULL, &flags);
-		mod_vpage(t->rpc.vmem, start, paddr, clear_bits(flags, VM_U));
-	}
+	while (pages--)
+		clear_vpage_flags(t->rpc.vmem, start + pages * page_size, VM_U);
 }
 
 /**
@@ -407,12 +403,8 @@ static void mark_rpc_accessible(struct tcb *t, vm_t start, vm_t end)
 	size_t page_size = BASE_PAGE_SIZE;
 	size_t size = end - start;
 	size_t pages = size / page_size;
-	while (pages--) {
-		/** @todo something like mod_vpage_flags could be faster */
-		vmflags_t flags; pm_t paddr;
-		stat_vpage(t->rpc.vmem, start, &paddr, NULL, &flags);
-		mod_vpage(t->rpc.vmem, start, paddr, set_bits(flags, VM_U));
-	}
+	while (pages--)
+		set_vpage_flags(t->rpc.vmem, start + pages * page_size, VM_U);
 }
 
 void save_context(struct tcb *t)
diff --git a/include/arch/vmem.h b/include/arch/vmem.h
index bbaf9c4..1a2ab7e 100644
--- a/include/arch/vmem.h
+++ b/include/arch/vmem.h
@@ -48,6 +48,24 @@ stat_t map_vpage(struct vmem *branch, pm_t paddr, vm_t vaddr, vmflags_t flags,
 stat_t unmap_vpage(struct vmem *branch, vm_t vaddr);
 
 /**
+ * Set flags in page at virtual address \p vaddr.
+ *
+ * @param branch Branch in which to work.
+ * @param vaddr Virtual address of page.
+ * @param flags Flags to set.
+ */
+stat_t set_vpage_flags(struct vmem *branch, vm_t vaddr, vmflags_t flags);
+
+/**
+ * Clear flags in page at virtual address \p vaddr.
+ *
+ * @param branch Branch in which to work.
+ * @param vaddr Virtual address of page.
+ * @param flags Flags to clear.
+ */
+stat_t clear_vpage_flags(struct vmem *branch, vm_t vaddr, vmflags_t flags);
+
+/**
  * Modify page mapping physical address and flags.
  *
  * Note that changing the order of a page is not supported, to do that unmap and