From 269d28ac3bfe7bce250eb21b74fcf2c72a0bfdc9 Mon Sep 17 00:00:00 2001
From: Shell <smokewood@qq.com>
Date: Mon, 2 Dec 2024 15:13:46 +0800
Subject: [PATCH] feat: mm: install page in a discrete method

This patch refactors the `rt_page_install` function by delegating specific
operations to new helper functions. Besides, the contiguous page regions
are now separated to segments of fixed size. The goal is to improve the
overall code readability, enhance modularity, and ensure better handling
of page installation logic through clearer separation of concerns.

Changes:
- Introduced `_get_mpr_ready_n_install` to encapsulate memory preparation
  and page installation logic.
- Added `_update_region_list` for updating the installed page registry.
- Defined `_PAGE_STRIPE` for optimized region processing.
- Modified `rt_page_install` to handle regions in smaller chunks using
  helper functions for better maintainability.
- Improved locking mechanisms with `rt_spin_lock` for thread safety.
- Reduced code duplication and clarified shadow region calculations.

Signed-off-by: Shell <smokewood@qq.com>
---
 components/mm/mm_page.c | 80 ++++++++++++++++++++++++++++++++---------
 1 file changed, 64 insertions(+), 16 deletions(-)

diff --git a/components/mm/mm_page.c b/components/mm/mm_page.c
index a608b31565..263ea8ed90 100644
--- a/components/mm/mm_page.c
+++ b/components/mm/mm_page.c
@@ -1112,34 +1112,82 @@ static int _load_mpr_area(void *head, void *tail)
     return err;
 }
 
+static int _get_mpr_ready_n_install(rt_ubase_t inst_head, rt_ubase_t inst_end)
+{
+    int err;
+    rt_region_t shadow;
+    rt_region_t region =
+    {
+        .start = inst_head,
+        .end = inst_end,
+    };
+    void *head, *tail;
+
+    shadow.start = region.start & ~shadow_mask;
+    shadow.end = FLOOR(region.end, shadow_mask + 1);
+    head = addr_to_page(page_start, (void *)shadow.start);
+    tail = addr_to_page(page_start, (void *)shadow.end);
+
+    err = _load_mpr_area(head, tail);
+
+    if (err == RT_EOK)
+    {
+        _install_page(rt_mpr_start, region, _page_insert);
+    }
+
+    return err;
+}
+
+static void _update_region_list(struct installed_page_reg *member,
+                                rt_ubase_t inst_head, rt_ubase_t inst_end)
+{
+    rt_spin_lock_init(&member->lock);
+
+    rt_spin_lock(&_inst_page_reg_lock);
+
+    member->region_area.start = inst_head;
+    member->region_area.end = inst_end;
+    member->usage_trace = ut_bitmap;
+
+    member->next = _inst_page_reg_head;
+    _inst_page_reg_head = member;
+
+    rt_spin_unlock(&_inst_page_reg_lock);
+}
+
+#define _PAGE_STRIPE (1 << (RT_PAGE_MAX_ORDER + ARCH_PAGE_SHIFT - 1))
 int rt_page_install(rt_region_t region)
 {
     int err = -RT_EINVAL;
-    rt_region_t shadow;
-    void *head, *tail;
 
     if (region.end != region.start && !(region.start & ARCH_PAGE_MASK) &&
         !(region.end & ARCH_PAGE_MASK))
     {
-        shadow.start = region.start & ~shadow_mask;
-        shadow.end = FLOOR(region.end, shadow_mask + 1);
-        head = addr_to_page(page_start, (void *)shadow.start);
-        tail = addr_to_page(page_start, (void *)shadow.end);
+        rt_ubase_t inst_head = region.start;
+        rt_ubase_t inst_end = region.end;
+        rt_ubase_t iter = inst_head;
+        struct installed_page_reg *installed_pgreg =
+            rt_malloc(sizeof(*installed_pgreg));
 
-        err = _load_mpr_area(head, tail);
-
-        if (err == RT_EOK)
+        if (installed_pgreg)
         {
-            struct installed_page_reg *installed_pgreg =
-                rt_malloc(sizeof(*installed_pgreg));
+            _update_region_list(installed_pgreg, inst_head, inst_end);
 
-            if (installed_pgreg)
+            if ((rt_ubase_t)iter & shadow_mask)
             {
-                installed_pgreg->region_area.start = region.start;
-                installed_pgreg->region_area.end = region.end;
+                iter = RT_ALIGN((rt_ubase_t)inst_head, _PAGE_STRIPE);
+                _get_mpr_ready_n_install(inst_head, iter < inst_end ? iter : inst_end);
+            }
 
-                _update_region_list(installed_pgreg);
-                _install_page(rt_mpr_start, region, _page_insert);
+            for (rt_ubase_t next = iter + _PAGE_STRIPE; next < inst_end;
+                 iter = next, next += _PAGE_STRIPE)
+            {
+                _get_mpr_ready_n_install(iter, next);
+            }
+
+            if (iter < inst_end)
+            {
+                _get_mpr_ready_n_install(iter, inst_end);
             }
         }
     }