Forgot to append the patch...
Greetings
Christoph
diff -uNr 4-11-3/ipc/shm.c c/ipc/shm.c
--- 4-11-3/ipc/shm.c Wed Oct 4 15:58:02 2000
+++ c/ipc/shm.c Tue Nov 14 17:43:01 2000
@@ -80,6 +80,7 @@
unsigned long shm_npages; /* size of segment (pages) */
pte_t **shm_dir; /* ptr to arr of ptrs to frames */
int id;
+ struct list_head list;
union permap {
struct shmem {
time_t atime;
@@ -92,7 +93,6 @@
} shmem;
struct zero {
struct semaphore sema;
- struct list_head list;
} zero;
} permap;
};
@@ -106,7 +106,6 @@
#define shm_name permap.shmem.nm
#define shm_flags shm_perm.mode
#define zsem permap.zero.sema
-#define zero_list permap.zero.list
static struct ipc_ids shm_ids;
@@ -129,13 +128,12 @@
static int sysvipc_shm_read_proc(char *buffer, char **start, off_t offset, int length, int *eof, void *data);
#endif
-static void zshm_swap (int prio, int gfp_mask);
-static void zmap_unuse(swp_entry_t entry, struct page *page);
static void shmzero_open(struct vm_area_struct *shmd);
static void shmzero_close(struct vm_area_struct *shmd);
static struct page *shmzero_nopage(struct vm_area_struct * shmd, unsigned long address, int no_share);
static int zero_id;
static struct shmid_kernel zshmid_kernel;
+static struct list_head shm_list;
static struct dentry *zdent;
#define SHM_FS_MAGIC 0x02011994
@@ -223,7 +221,7 @@
#endif
zero_id = ipc_addid(&shm_ids, &zshmid_kernel.shm_perm, 1);
shm_unlock(zero_id);
- INIT_LIST_HEAD(&zshmid_kernel.zero_list);
+ INIT_LIST_HEAD(&shm_list);
zdent = d_alloc_root(get_empty_inode());
return;
}
@@ -572,13 +570,13 @@
if (pages == 0)
return NULL;
- ret = kmalloc ((dir+1) * sizeof(pte_t *), GFP_KERNEL);
+ ret = kmalloc ((dir+1) * sizeof(pte_t *), GFP_USER);
if (!ret)
goto nomem;
for (ptr = ret; ptr < ret+dir ; ptr++)
{
- *ptr = (pte_t *)__get_free_page (GFP_KERNEL);
+ *ptr = (pte_t *)__get_free_page (GFP_USER);
if (!*ptr)
goto free;
init_ptes (*ptr, PTES_PER_PAGE);
@@ -586,7 +584,7 @@
/* The last one is probably not of PAGE_SIZE: we use kmalloc */
if (last) {
- *ptr = kmalloc (last*sizeof(pte_t), GFP_KERNEL);
+ *ptr = kmalloc (last*sizeof(pte_t), GFP_USER);
if (!*ptr)
goto free;
init_ptes (*ptr, last);
@@ -724,7 +722,7 @@
struct shmid_kernel *shp;
pte_t **dir;
- shp = (struct shmid_kernel *) kmalloc (sizeof (*shp) + namelen, GFP_KERNEL);
+ shp = (struct shmid_kernel *) kmalloc (sizeof (*shp) + namelen, GFP_USER);
if (!shp)
return ERR_PTR(-ENOMEM);
@@ -737,11 +735,17 @@
shp->shm_npages = numpages;
shp->shm_nattch = 0;
shp->shm_namelen = namelen;
+ shm_lockall();
+ list_add_tail(&shp->list, &shm_list);
+ shm_unlockall();
return(shp);
}
static void seg_free(struct shmid_kernel *shp, int doacc)
{
+ shm_lockall();
+ list_del(&shp->list);
+ shm_unlockall();
shm_free (shp->shm_dir, shp->shm_npages, doacc);
kfree(shp);
}
@@ -1460,32 +1464,45 @@
return(page);
}
-#define OKAY 0
-#define RETRY 1
-#define FAILED 2
-
-static int shm_swap_core(struct shmid_kernel *shp, unsigned long idx, swp_entry_t swap_entry, int *counter, struct page **outpage)
+static int shm_swap_core(struct shmid_kernel *shp, unsigned long * idx,
+ swp_entry_t swap_entry, struct page **outpage)
{
pte_t page;
struct page *page_map;
+ int lowonly = 0;
+ int index;
+
+ while ((index = (*idx)++) < shp->shm_npages) {
+ page = SHM_ENTRY(shp, index);
+ if (!pte_present(page))
+ continue;
+ page_map = pte_page(page);
+ if (page_map->zone->free_pages > page_map->zone->pages_high)
+ continue;
+ if (lowonly && PageHighMem (page_map))
+ continue;
+
+ if (shp->id != zero_id) swap_attempts++;
+
+ if (page_count(page_map) != 1)
+ continue;
+
+ if (TryLockPage(page_map)) {
+ printk ("shm_swap_core: page locked\n");
+ continue;
+ }
+
+ page_map = prepare_highmem_swapout(page_map);
+ if (page_map)
+ goto swap_out;
+
+ lowonly = 1; /* We continue to free some lowmem pages */
+ }
+
+ return 0;
- page = SHM_ENTRY(shp, idx);
- if (!pte_present(page))
- return RETRY;
- page_map = pte_page(page);
- if (page_map->zone->free_pages > page_map->zone->pages_high)
- return RETRY;
- if (shp->id != zero_id) swap_attempts++;
-
- if (--*counter < 0) /* failed */
- return FAILED;
- if (page_count(page_map) != 1)
- return RETRY;
-
- lock_page(page_map);
- if (!(page_map = prepare_highmem_swapout(page_map)))
- return FAILED;
- SHM_ENTRY (shp, idx) = swp_entry_to_pte(swap_entry);
+swap_out:
+ SHM_ENTRY (shp, index) = swp_entry_to_pte(swap_entry);
/* add the locked page to the swap cache before allowing
the swapin path to run lookup_swap_cache(). This avoids
@@ -1493,97 +1510,81 @@
NOTE: we just accounted the swap space reference for this
swap cache page at __get_swap_page() time. */
add_to_swap_cache(*outpage = page_map, swap_entry);
- return OKAY;
-}
-
-static void shm_swap_postop(struct page *page)
-{
- lock_kernel();
- rw_swap_page(WRITE, page, 0);
- unlock_kernel();
- page_cache_release(page);
-}
-
-static int shm_swap_preop(swp_entry_t *swap_entry)
-{
- lock_kernel();
- /* subtle: preload the swap count for the swap cache. We can't
- increase the count inside the critical section as we can't release
- the shm_lock there. And we can't acquire the big lock with the
- shm_lock held (otherwise we would deadlock too easily). */
- *swap_entry = __get_swap_page(2);
- if (!(*swap_entry).val) {
- unlock_kernel();
- return 1;
- }
- unlock_kernel();
- return 0;
+ return 1;
}
/*
- * Goes through counter = (shm_rss >> prio) present shm pages.
+ * Tries to free count pages
*/
-static unsigned long swap_id; /* currently being swapped */
-static unsigned long swap_idx; /* next to swap */
-int shm_swap (int prio, int gfp_mask)
+int shm_swap (int count, int gfp_mask)
{
+ static unsigned long swap_idx; /* next to swap */
struct shmid_kernel *shp;
swp_entry_t swap_entry;
- unsigned long id, idx;
- int loop = 0;
- int counter;
+ int counter = 0;
struct page * page_map;
+ struct list_head *p;
/*
* Push this inside:
*/
- if (!(gfp_mask & __GFP_IO))
+ if (!(gfp_mask & __GFP_IO)) {
+ printk ("shm_swap !__GFP_IO\n");
return 0;
+ }
- zshm_swap(prio, gfp_mask);
- counter = shm_rss >> prio;
- if (!counter)
- return 0;
- if (shm_swap_preop(&swap_entry))
- return 0;
+next:
+ if (counter >= count)
+ goto out;
+
+ lock_kernel();
+ /* subtle: preload the swap count for the swap cache. We can't
+ increase the count inside the critical section as we can't release
+ the shm_lock there. And we can't acquire the big lock with the
+ shm_lock held (otherwise we would deadlock too easily). */
+ swap_entry = __get_swap_page(2);
+ if (!swap_entry.val) {
+ unlock_kernel();
+ goto out;
+ }
+ unlock_kernel();
shm_lockall();
-check_id:
- shp = shm_get(swap_id);
- if(shp==NULL || shp->shm_flags & PRV_LOCKED) {
-next_id:
+ list_for_each (p, &shm_list) {
+ shp = list_entry (p, struct shmid_kernel, list);
+
+ if (shp->id != zero_id && shp->shm_flags & PRV_LOCKED)
+ continue;
+ if (shm_swap_core(shp, &swap_idx, swap_entry, &page_map))
+ goto found;
+
swap_idx = 0;
- if (++swap_id > shm_ids.max_id) {
- swap_id = 0;
- if (loop) {
-failed:
- shm_unlockall();
- __swap_free(swap_entry, 2);
- return 0;
- }
- loop = 1;
- }
- goto check_id;
}
- id = swap_id;
+ shm_unlockall();
+ __swap_free(swap_entry, 2);
+out:
+ printk ("shm_swap %d/%d\n", counter, count);
+ return counter;
-check_table:
- idx = swap_idx++;
- if (idx >= shp->shm_npages)
- goto next_id;
+found:
+ if (shp->id != zero_id) {
+ counter++;
+ swap_successes++;
+ shm_swp++;
+ shm_rss--;
+ }
- switch (shm_swap_core(shp, idx, swap_entry, &counter, &page_map)) {
- case RETRY: goto check_table;
- case FAILED: goto failed;
- }
- swap_successes++;
- shm_swp++;
- shm_rss--;
- shm_unlockall();
+ /* adjust shm_list to start at the last processed segment */
+ list_del (&shm_list);
+ list_add_tail (&shm_list, &shp->list);
- shm_swap_postop(page_map);
- return 1;
+ shm_unlockall();
+ lock_kernel();
+ rw_swap_page(WRITE, page_map, 0);
+ unlock_kernel();
+ page_cache_release(page_map);
+ goto next;
}
/*
@@ -1597,48 +1598,44 @@
pte = pte_mkdirty(mk_pte(page, PAGE_SHARED));
SHM_ENTRY(shp, idx) = pte;
page_cache_get(page);
- shm_rss++;
- shm_swp--;
+ if (shp->id != zero_id) {
+ shm_rss++;
+ shm_swp--;
+ }
swap_free(entry);
}
-static int shm_unuse_core(struct shmid_kernel *shp, swp_entry_t entry, struct page *page)
-{
- int n;
-
- for (n = 0; n < shp->shm_npages; n++) {
- if (pte_none(SHM_ENTRY(shp,n)))
- continue;
- if (pte_present(SHM_ENTRY(shp,n)))
- continue;
- if (pte_to_swp_entry(SHM_ENTRY(shp,n)).val == entry.val) {
- shm_unuse_page(shp, n, entry, page);
- return 1;
- }
- }
- return 0;
-}
-
/*
* unuse_shm() search for an eventually swapped out shm page.
*/
void shm_unuse(swp_entry_t entry, struct page *page)
{
- int i;
+ unsigned long n;
+ struct list_head *p;
shm_lockall();
- for (i = 0; i <= shm_ids.max_id; i++) {
- struct shmid_kernel *shp = shm_get(i);
- if(shp==NULL)
- continue;
- if (shm_unuse_core(shp, entry, page))
- goto out;
+ list_for_each (p, &shm_list) {
+ struct shmid_kernel *shp;
+
+ shp = list_entry(p, struct shmid_kernel, list);
+
+ printk ("shm_unuse scanning %d\n", shp->id);
+ for (n = 0; n < shp->shm_npages; n++) {
+ if (pte_none(SHM_ENTRY(shp,n)))
+ continue;
+ if (pte_present(SHM_ENTRY(shp,n)))
+ continue;
+ if (pte_to_swp_entry(SHM_ENTRY(shp,n)).val == entry.val) {
+ shm_unuse_page(shp, n, entry, page);
+ shm_unlockall();
+ return;
+ }
+ }
+
}
-out:
shm_unlockall();
- zmap_unuse(entry, page);
}
#ifdef CONFIG_PROC_FS
@@ -1710,9 +1707,6 @@
#define VMA_TO_SHP(vma) ((vma)->vm_file->private_data)
-static spinlock_t zmap_list_lock = SPIN_LOCK_UNLOCKED;
-static unsigned long zswap_idx; /* next to swap */
-static struct shmid_kernel *zswap_shp = &zshmid_kernel;
static int zshm_rss;
static struct vm_operations_struct shmzero_vm_ops = {
@@ -1786,9 +1780,6 @@
init_MUTEX(&shp->zsem);
vma->vm_ops = &shmzero_vm_ops;
shmzero_open(vma);
- spin_lock(&zmap_list_lock);
- list_add(&shp->zero_list, &zshmid_kernel.zero_list);
- spin_unlock(&zmap_list_lock);
return 0;
}
@@ -1797,9 +1788,9 @@
struct shmid_kernel *shp;
shp = VMA_TO_SHP(shmd);
- down(&shp->zsem);
+ shm_lock(zero_id);
shp->shm_nattch++;
- up(&shp->zsem);
+ shm_unlock(zero_id);
}
static void shmzero_close(struct vm_area_struct *shmd)
@@ -1808,19 +1799,12 @@
struct shmid_kernel *shp;
shp = VMA_TO_SHP(shmd);
- down(&shp->zsem);
+ shm_lock(zero_id);
if (--shp->shm_nattch == 0)
done = 1;
- up(&shp->zsem);
- if (done) {
- spin_lock(&zmap_list_lock);
- if (shp == zswap_shp)
- zswap_shp = list_entry(zswap_shp->zero_list.next,
- struct shmid_kernel, zero_list);
- list_del(&shp->zero_list);
- spin_unlock(&zmap_list_lock);
+ shm_unlock(zero_id);
+ if (done)
seg_free(shp, 0);
- }
}
static struct page * shmzero_nopage(struct vm_area_struct * shmd, unsigned long address, int no_share)
@@ -1841,79 +1825,3 @@
up(&shp->zsem);
return(page);
}
-
-static void zmap_unuse(swp_entry_t entry, struct page *page)
-{
- struct shmid_kernel *shp;
-
- spin_lock(&zmap_list_lock);
- shm_lock(zero_id);
- for (shp = list_entry(zshmid_kernel.zero_list.next, struct shmid_kernel,
- zero_list); shp != &zshmid_kernel;
- shp = list_entry(shp->zero_list.next, struct shmid_kernel,
- zero_list)) {
- if (shm_unuse_core(shp, entry, page))
- break;
- }
- shm_unlock(zero_id);
- spin_unlock(&zmap_list_lock);
-}
-
-static void zshm_swap (int prio, int gfp_mask)
-{
- struct shmid_kernel *shp;
- swp_entry_t swap_entry;
- unsigned long idx;
- int loop = 0;
- int counter;
- struct page * page_map;
-
- counter = zshm_rss >> prio;
- if (!counter)
- return;
-next:
- if (shm_swap_preop(&swap_entry))
- return;
-
- spin_lock(&zmap_list_lock);
- shm_lock(zero_id);
- if (zshmid_kernel.zero_list.next == 0)
- goto failed;
-next_id:
- if (zswap_shp == &zshmid_kernel) {
- if (loop) {
-failed:
- shm_unlock(zero_id);
- spin_unlock(&zmap_list_lock);
- __swap_free(swap_entry, 2);
- return;
- }
- zswap_shp = list_entry(zshmid_kernel.zero_list.next,
- struct shmid_kernel, zero_list);
- zswap_idx = 0;
- loop = 1;
- }
- shp = zswap_shp;
-
-check_table:
- idx = zswap_idx++;
- if (idx >= shp->shm_npages) {
- zswap_shp = list_entry(zswap_shp->zero_list.next,
- struct shmid_kernel, zero_list);
- zswap_idx = 0;
- goto next_id;
- }
-
- switch (shm_swap_core(shp, idx, swap_entry, &counter, &page_map)) {
- case RETRY: goto check_table;
- case FAILED: goto failed;
- }
- shm_unlock(zero_id);
- spin_unlock(&zmap_list_lock);
-
- shm_swap_postop(page_map);
- if (counter)
- goto next;
- return;
-}
-
diff -uNr 4-11-3/mm/vmscan.c c/mm/vmscan.c
--- 4-11-3/mm/vmscan.c Mon Nov 13 09:49:43 2000
+++ c/mm/vmscan.c Tue Nov 14 15:01:59 2000
@@ -725,6 +725,8 @@
* IO.
*/
if (can_get_io_locks && !launder_loop && free_shortage()) {
+ printk ("page_launder: ");
+ cleaned_pages += shm_swap (free_shortage(), gfp_mask);
launder_loop = 1;
/* If we cleaned pages, never do synchronous IO. */
if (cleaned_pages)
@@ -924,13 +926,6 @@
*/
shrink_dcache_memory(priority, gfp_mask);
shrink_icache_memory(priority, gfp_mask);
-
- /* Try to get rid of some shared memory pages.. */
- while (shm_swap(priority, gfp_mask)) {
- made_progress = 1;
- if (--count <= 0)
- goto done;
- }
/*
* Then, try to page stuff out..
-
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This archive was generated by hypermail 2b29 : Wed Nov 15 2000 - 21:00:27 EST