diff mbox series

[2/4] mini-os: mm: remove not needed struct chunk_tail_st

Message ID 20240722150141.31391-3-jgross@suse.com (mailing list archive)
State New
Headers show
Series mini-os: cleanup of mm.c | expand

Commit Message

Jürgen Groß July 22, 2024, 3:01 p.m. UTC 
The struct chunk_tail_st isn't really used other than writing to it.

Remove it in order to simplify the code.

Signed-off-by: Juergen Gross <jgross@suse.com>
---
 mm.c | 20 --------------------
 1 file changed, 20 deletions(-)

Comments

Samuel Thibault July 22, 2024, 9:30 p.m. UTC | #1 
Juergen Gross, le lun. 22 juil. 2024 17:01:39 +0200, a ecrit:
> The struct chunk_tail_st isn't really used other than writing to it.
> 
> Remove it in order to simplify the code.
> 
> Signed-off-by: Juergen Gross <jgross@suse.com>

Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

> ---
>  mm.c | 20 --------------------
>  1 file changed, 20 deletions(-)
> 
> diff --git a/mm.c b/mm.c
> index 1dcd954c..2cc49e94 100644
> --- a/mm.c
> +++ b/mm.c
> @@ -123,7 +123,6 @@ static void map_free(unsigned long first_page, unsigned long nr_pages)
>  /* BINARY BUDDY ALLOCATOR */
>  
>  typedef struct chunk_head_st chunk_head_t;
> -typedef struct chunk_tail_st chunk_tail_t;
>  
>  struct chunk_head_st {
>      chunk_head_t  *next;
> @@ -131,10 +130,6 @@ struct chunk_head_st {
>      int            level;
>  };
>  
> -struct chunk_tail_st {
> -    int level;
> -};
> -
>  /* Linked lists of free chunks of different powers-of-two in size. */
>  #define FREELIST_SIZE ((sizeof(void *) << 3) - PAGE_SHIFT)
>  static chunk_head_t *free_head[FREELIST_SIZE];
> @@ -151,7 +146,6 @@ static void init_page_allocator(unsigned long min, unsigned long max)
>      unsigned long range;
>      unsigned long r_min, r_max;
>      chunk_head_t *ch;
> -    chunk_tail_t *ct;
>  
>      printk("MM: Initialise page allocator for %lx(%lx)-%lx(%lx)\n",
>             (u_long)to_virt(min), min, (u_long)to_virt(max), max);
> @@ -215,14 +209,12 @@ static void init_page_allocator(unsigned long min, unsigned long max)
>              ch = (chunk_head_t *)r_min;
>              r_min += 1UL << i;
>              range -= 1UL << i;
> -            ct = (chunk_tail_t *)r_min - 1;
>              i -= PAGE_SHIFT;
>              ch->level       = i;
>              ch->next        = free_head[i];
>              ch->pprev       = &free_head[i];
>              ch->next->pprev = &ch->next;
>              free_head[i]    = ch;
> -            ct->level       = i;
>          }
>      }
>  
> @@ -234,7 +226,6 @@ unsigned long alloc_pages(int order)
>  {
>      int i;
>      chunk_head_t *alloc_ch, *spare_ch;
> -    chunk_tail_t            *spare_ct;
>  
>      if ( !chk_free_pages(1UL << order) )
>          goto no_memory;
> @@ -261,14 +252,11 @@ unsigned long alloc_pages(int order)
>          i--;
>          spare_ch = (chunk_head_t *)((char *)alloc_ch +
>                                      (1UL << (i + PAGE_SHIFT)));
> -        spare_ct = (chunk_tail_t *)((char *)spare_ch +
> -                                    (1UL << (i + PAGE_SHIFT))) - 1;
>  
>          /* Create new header for spare chunk. */
>          spare_ch->level = i;
>          spare_ch->next  = free_head[i];
>          spare_ch->pprev = &free_head[i];
> -        spare_ct->level = i;
>  
>          /* Link in the spare chunk. */
>          spare_ch->next->pprev = &spare_ch->next;
> @@ -289,7 +277,6 @@ EXPORT_SYMBOL(alloc_pages);
>  void free_pages(void *pointer, int order)
>  {
>      chunk_head_t *freed_ch, *to_merge_ch;
> -    chunk_tail_t *freed_ct;
>      unsigned long mask;
>  
>      /* First free the chunk */
> @@ -297,8 +284,6 @@ void free_pages(void *pointer, int order)
>  
>      /* Create free chunk */
>      freed_ch = (chunk_head_t *)pointer;
> -    freed_ct = (chunk_tail_t *)((char *)pointer +
> -                                (1UL << (order + PAGE_SHIFT))) - 1;
>  
>      /* Now, possibly we can conseal chunks together */
>      while ( order < FREELIST_SIZE )
> @@ -320,9 +305,6 @@ void free_pages(void *pointer, int order)
>              if ( allocated_in_map(virt_to_pfn(to_merge_ch)) ||
>                   to_merge_ch->level != order )
>                  break;
> -
> -            /* Merge with successor */
> -            freed_ct = (chunk_tail_t *)((char *)to_merge_ch + mask) - 1;
>          }
>  
>          /* We are committed to merging, unlink the chunk */
> @@ -336,8 +318,6 @@ void free_pages(void *pointer, int order)
>      freed_ch->level = order;
>      freed_ch->next  = free_head[order];
>      freed_ch->pprev = &free_head[order];
> -    freed_ct->level = order;
> -
>      freed_ch->next->pprev = &freed_ch->next;
>      free_head[order] = freed_ch;
>  
> -- 
> 2.43.0
>
diff mbox series

Patch

diff --git a/mm.c b/mm.c
index 1dcd954c..2cc49e94 100644
--- a/mm.c
+++ b/mm.c
@@ -123,7 +123,6 @@  static void map_free(unsigned long first_page, unsigned long nr_pages)
 /* BINARY BUDDY ALLOCATOR */
 
 typedef struct chunk_head_st chunk_head_t;
-typedef struct chunk_tail_st chunk_tail_t;
 
 struct chunk_head_st {
     chunk_head_t  *next;
@@ -131,10 +130,6 @@  struct chunk_head_st {
     int            level;
 };
 
-struct chunk_tail_st {
-    int level;
-};
-
 /* Linked lists of free chunks of different powers-of-two in size. */
 #define FREELIST_SIZE ((sizeof(void *) << 3) - PAGE_SHIFT)
 static chunk_head_t *free_head[FREELIST_SIZE];
@@ -151,7 +146,6 @@  static void init_page_allocator(unsigned long min, unsigned long max)
     unsigned long range;
     unsigned long r_min, r_max;
     chunk_head_t *ch;
-    chunk_tail_t *ct;
 
     printk("MM: Initialise page allocator for %lx(%lx)-%lx(%lx)\n",
            (u_long)to_virt(min), min, (u_long)to_virt(max), max);
@@ -215,14 +209,12 @@  static void init_page_allocator(unsigned long min, unsigned long max)
             ch = (chunk_head_t *)r_min;
             r_min += 1UL << i;
             range -= 1UL << i;
-            ct = (chunk_tail_t *)r_min - 1;
             i -= PAGE_SHIFT;
             ch->level       = i;
             ch->next        = free_head[i];
             ch->pprev       = &free_head[i];
             ch->next->pprev = &ch->next;
             free_head[i]    = ch;
-            ct->level       = i;
         }
     }
 
@@ -234,7 +226,6 @@  unsigned long alloc_pages(int order)
 {
     int i;
     chunk_head_t *alloc_ch, *spare_ch;
-    chunk_tail_t            *spare_ct;
 
     if ( !chk_free_pages(1UL << order) )
         goto no_memory;
@@ -261,14 +252,11 @@  unsigned long alloc_pages(int order)
         i--;
         spare_ch = (chunk_head_t *)((char *)alloc_ch +
                                     (1UL << (i + PAGE_SHIFT)));
-        spare_ct = (chunk_tail_t *)((char *)spare_ch +
-                                    (1UL << (i + PAGE_SHIFT))) - 1;
 
         /* Create new header for spare chunk. */
         spare_ch->level = i;
         spare_ch->next  = free_head[i];
         spare_ch->pprev = &free_head[i];
-        spare_ct->level = i;
 
         /* Link in the spare chunk. */
         spare_ch->next->pprev = &spare_ch->next;
@@ -289,7 +277,6 @@  EXPORT_SYMBOL(alloc_pages);
 void free_pages(void *pointer, int order)
 {
     chunk_head_t *freed_ch, *to_merge_ch;
-    chunk_tail_t *freed_ct;
     unsigned long mask;
 
     /* First free the chunk */
@@ -297,8 +284,6 @@  void free_pages(void *pointer, int order)
 
     /* Create free chunk */
     freed_ch = (chunk_head_t *)pointer;
-    freed_ct = (chunk_tail_t *)((char *)pointer +
-                                (1UL << (order + PAGE_SHIFT))) - 1;
 
     /* Now, possibly we can conseal chunks together */
     while ( order < FREELIST_SIZE )
@@ -320,9 +305,6 @@  void free_pages(void *pointer, int order)
             if ( allocated_in_map(virt_to_pfn(to_merge_ch)) ||
                  to_merge_ch->level != order )
                 break;
-
-            /* Merge with successor */
-            freed_ct = (chunk_tail_t *)((char *)to_merge_ch + mask) - 1;
         }
 
         /* We are committed to merging, unlink the chunk */
@@ -336,8 +318,6 @@  void free_pages(void *pointer, int order)
     freed_ch->level = order;
     freed_ch->next  = free_head[order];
     freed_ch->pprev = &free_head[order];
-    freed_ct->level = order;
-
     freed_ch->next->pprev = &freed_ch->next;
     free_head[order] = freed_ch;