Index: linux/kernel/fork.c
diff -u linux/kernel/fork.c:1.1.1.3 linux/kernel/fork.c:1.1.1.1.2.6
--- linux/kernel/fork.c:1.1.1.3 Thu Dec 3 12:55:12 1998
+++ linux/kernel/fork.c Thu Dec 31 17:56:28 1998
@@ -567,6 +570,7 @@
/* ok, now we should be set up.. */
p->swappable = 1;
+ p->trashing_memory = 0;
p->exit_signal = clone_flags & CSIGNAL;
p->pdeath_signal = 0;
Index: linux/mm/vmscan.c
diff -u linux/mm/vmscan.c:1.1.1.8 linux/mm/vmscan.c:1.1.1.1.2.49
--- linux/mm/vmscan.c:1.1.1.8 Fri Jan 1 19:12:54 1999
+++ linux/mm/vmscan.c Fri Jan 1 20:29:19 1999
@@ -162,8 +162,9 @@
* copy in memory, so we add it to the swap
* cache. */
if (PageSwapCache(page_map)) {
+ entry = atomic_read(&page_map->count);
__free_page(page_map);
- return (atomic_read(&page_map->count) == 0);
+ return entry;
}
add_to_swap_cache(page_map, entry);
/* We checked we were unlocked way up above, and we
@@ -180,8 +181,9 @@
* asynchronously. That's no problem, shrink_mmap() can
* correctly clean up the occassional unshared page
* which gets left behind in the swap cache. */
+ entry = atomic_read(&page_map->count);
__free_page(page_map);
- return 1; /* we slept: the process may not exist any more */
+ return entry; /* we slept: the process may not exist any more */
}
/* The page was _not_ dirty, but still has a zero age. It must
@@ -194,8 +196,9 @@
set_pte(page_table, __pte(entry));
flush_tlb_page(vma, address);
swap_duplicate(entry);
+ entry = atomic_read(&page_map->count);
__free_page(page_map);
- return (atomic_read(&page_map->count) == 0);
+ return entry;
}
/*
* A clean page to be discarded? Must be mmap()ed from
@@ -210,7 +213,7 @@
flush_cache_page(vma, address);
pte_clear(page_table);
flush_tlb_page(vma, address);
- entry = (atomic_read(&page_map->count) == 1);
+ entry = atomic_read(&page_map->count);
__free_page(page_map);
return entry;
}
@@ -369,8 +372,14 @@
* swapped out. If the swap-out fails, we clear swap_cnt so the
* task won't be selected again until all others have been tried.
*/
- counter = ((PAGEOUT_WEIGHT * nr_tasks) >> 10) >> priority;
+ counter = nr_tasks / (priority+1);
+ if (counter < 1)
+ counter = 1;
+ if (counter > nr_tasks)
+ counter = nr_tasks;
+
for (; counter >= 0; counter--) {
+ int retval;
assign = 0;
max_cnt = 0;
pbest = NULL;
@@ -382,15 +391,8 @@
continue;
if (p->mm->rss <= 0)
continue;
- if (assign) {
- /*
- * If we didn't select a task on pass 1,
- * assign each task a new swap_cnt.
- * Normalise the number of pages swapped
- * by multiplying by (RSS / 1MB)
- */
- p->swap_cnt = AGE_CLUSTER_SIZE(p->mm->rss);
- }
+ if (assign)
+ p->swap_cnt = p->mm->rss;
if (p->swap_cnt > max_cnt) {
max_cnt = p->swap_cnt;
pbest = p;
@@ -404,14 +406,13 @@
}
goto out;
}
- pbest->swap_cnt--;
-
/*
* Nonzero means we cleared out something, but only "1" means
* that we actually free'd up a page as a result.
*/
- if (swap_out_process(pbest, gfp_mask) == 1)
- return 1;
+ retval = swap_out_process(pbest, gfp_mask);
+ if (retval)
+ return retval;
}
out:
return 0;
@@ -438,44 +439,74 @@
printk ("Starting kswapd v%.*s\n", i, s);
}
-#define free_memory(fn) \
- count++; do { if (!--count) goto done; } while (fn)
+static int do_free_user_and_cache(int priority, int gfp_mask)
+{
+ switch (swap_out(priority, gfp_mask))
+ {
+ default:
+ shrink_mmap(priority, gfp_mask);
+ /*
+ * We done at least some swapping progress so return 1 in
+ * this case. -arca
+ */
+ return 1;
+ case 0:
+ /* swap_out() failed to swapout */
+ if (shrink_mmap(priority, gfp_mask))
+ return 1;
+ return 0;
+ case 1:
+ /* this would be the best but should not happen right now */
+ printk(KERN_DEBUG
+ "do_free_user_and_cache: swapout returned 1\n");
+ return 1;
+ }
+}
-static int kswapd_free_pages(int kswapd_state)
+static int do_free_page(int * state, int gfp_mask)
{
- unsigned long end_time;
+ int priority = 6;
- /* Always trim SLAB caches when memory gets low. */
- kmem_cache_reap(0);
+ kmem_cache_reap(gfp_mask);
+ switch (*state) {
+ do {
+ default:
+ if (do_free_user_and_cache(priority, gfp_mask))
+ return 1;
+ *state = 1;
+ case 1:
+ if (shm_swap(priority, gfp_mask))
+ return 1;
+ *state = 2;
+ case 2:
+ shrink_dcache_memory(priority, gfp_mask);
+ *state = 0;
+ } while (--priority >= 0);
+ }
+ return 0;
+}
+
+static int kswapd_free_pages(int kswapd_state)
+{
/* max one hundreth of a second */
- end_time = jiffies + (HZ-1)/100;
- do {
- int priority = 5;
- int count = pager_daemon.swap_cluster;
+ unsigned long end_time = jiffies + (HZ-1)/100;
- switch (kswapd_state) {
- do {
- default:
- free_memory(shrink_mmap(priority, 0));
- kswapd_state++;
- case 1:
- free_memory(shm_swap(priority, 0));
- kswapd_state++;
- case 2:
- free_memory(swap_out(priority, 0));
- shrink_dcache_memory(priority, 0);
- kswapd_state = 0;
- } while (--priority >= 0);
- return kswapd_state;
- }
-done:
- if (nr_free_pages > freepages.high + pager_daemon.swap_cluster)
+ do {
+ do_free_page(&kswapd_state, 0);
+ if (nr_free_pages > freepages.high)
break;
} while (time_before_eq(jiffies,end_time));
+ /* take kswapd_state on the stack to save some byte of memory */
return kswapd_state;
}
+static inline void enable_swap_tick(void)
+{
+ timer_table[SWAP_TIMER].expires = jiffies+(HZ+99)/100;
+ timer_active |= 1<<SWAP_TIMER;
+}
+
/*
* The background pageout daemon.
* Started as a kernel thread from the init process.
@@ -523,6 +554,7 @@
current->state = TASK_INTERRUPTIBLE;
flush_signals(current);
run_task_queue(&tq_disk);
+ enable_swap_tick();
schedule();
swapstats.wakeups++;
state = kswapd_free_pages(state);
@@ -542,35 +574,23 @@
* if we need more memory as part of a swap-out effort we
* will just silently return "success" to tell the page
* allocator to accept the allocation.
- *
- * We want to try to free "count" pages, and we need to
- * cluster them so that we get good swap-out behaviour. See
- * the "free_memory()" macro for details.
*/
int try_to_free_pages(unsigned int gfp_mask, int count)
{
- int retval;
-
+ int retval = 1;
lock_kernel();
- /* Always trim SLAB caches when memory gets low. */
- kmem_cache_reap(gfp_mask);
-
- retval = 1;
if (!(current->flags & PF_MEMALLOC)) {
- int priority;
-
current->flags |= PF_MEMALLOC;
-
- priority = 5;
- do {
- free_memory(shrink_mmap(priority, gfp_mask));
- free_memory(shm_swap(priority, gfp_mask));
- free_memory(swap_out(priority, gfp_mask));
- shrink_dcache_memory(priority, gfp_mask);
- } while (--priority >= 0);
- retval = 0;
-done:
+ while (count--)
+ {
+ static int state = 0;
+ if (!do_free_page(&state, gfp_mask))
+ {
+ retval = 0;
+ break;
+ }
+ }
current->flags &= ~PF_MEMALLOC;
}
unlock_kernel();
@@ -593,7 +613,8 @@
if (priority) {
p->counter = p->priority << priority;
wake_up_process(p);
- }
+ } else
+ enable_swap_tick();
}
/*
@@ -631,9 +652,8 @@
want_wakeup = 3;
kswapd_wakeup(p,want_wakeup);
- }
-
- timer_active |= (1<<SWAP_TIMER);
+ } else
+ enable_swap_tick();
}
/*
@@ -642,7 +662,6 @@
void init_swap_timer(void)
{
- timer_table[SWAP_TIMER].expires = jiffies;
timer_table[SWAP_TIMER].fn = swap_tick;
- timer_active |= (1<<SWAP_TIMER);
+ enable_swap_tick();
}
Index: linux/mm/swap_state.c
diff -u linux/mm/swap_state.c:1.1.1.4 linux/mm/swap_state.c:1.1.1.1.2.9
--- linux/mm/swap_state.c:1.1.1.4 Fri Jan 1 19:12:54 1999
+++ linux/mm/swap_state.c Fri Jan 1 19:25:33 1999
@@ -262,6 +262,9 @@
struct page * lookup_swap_cache(unsigned long entry)
{
struct page *found;
+#ifdef SWAP_CACHE_INFO
+ swap_cache_find_total++;
+#endif
while (1) {
found = find_page(&swapper_inode, entry);
@@ -269,8 +272,12 @@
return 0;
if (found->inode != &swapper_inode || !PageSwapCache(found))
goto out_bad;
- if (!PageLocked(found))
+ if (!PageLocked(found)) {
+#ifdef SWAP_CACHE_INFO
+ swap_cache_find_success++;
+#endif
return found;
+ }
__free_page(found);
__wait_on_page(found);
}