From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from digeo-nav01.digeo.com (digeo-nav01.digeo.com [192.168.1.233]) by packet.digeo.com (8.9.3+Sun/8.9.3) with SMTP id OAA06879 for ; Wed, 18 Sep 2002 14:31:06 -0700 (PDT) Message-ID: <3D88F099.81A50A89@digeo.com> Date: Wed, 18 Sep 2002 14:31:05 -0700 From: Andrew Morton MIME-Version: 1.0 Subject: Re: 2.5.35-mm1 References: <3D858515.ED128C76@digeo.com> <20020917160722.G39@toy.ucw.cz> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Pavel Machek Cc: lkml , "linux-mm@kvack.org" , "lse-tech@lists.sourceforge.net" List-ID: Pavel Machek wrote: > > Hi! > > > url: http://www.zip.com.au/~akpm/linux/patches/2.5/2.5.35/2.5.35-mm1/ > > > > Significant rework of the new sleep/wakeup code - make it look totally > > different from the current APIs to avoid confusion, and to make it > > simpler to use. > > Did you add any hooks to allow me to free memory for swsusp? I just did then. You'll need to call freed = shrink_all_memory(99); to free up 99 pages. It returns the number which it actually freed. If that's not 99 then it's time to give up. There is no oom-killer in this code path. I haven't tested it yet. And it's quite a long way back in the queue I'm afraid - it has a dependency chain, and I prefer to send stuff to Linus which has been tested for a couple of weeks, and hasn't changed for one week. Can you use the allocate-lots-then-free-it trick in the meanwhile? include/linux/swap.h | 1 + mm/vmscan.c | 46 ++++++++++++++++++++++++++++++++++++++++------ 2 files changed, 41 insertions, 6 deletions --- 2.5.36/mm/vmscan.c~swsusp-feature Wed Sep 18 13:55:20 2002 +++ 2.5.36-akpm/mm/vmscan.c Wed Sep 18 14:29:13 2002 @@ -694,12 +694,19 @@ try_to_free_pages(struct zone *classzone } /* - * kswapd will work across all this node's zones until they are all at - * pages_high. + * For kswapd, balance_pgdat() will work across all this node's zones until + * they are all at pages_high. + * + * If `nr_pages' is non-zero then it is the number of pages which are to be + * reclaimed, regardless of the zone occupancies. This is a software suspend + * special. + * + * Returns the number of pages which were actually freed. */ -static void kswapd_balance_pgdat(pg_data_t *pgdat) +static int balance_pgdat(pg_data_t *pgdat, int nr_pages) { - int priority = DEF_PRIORITY; + int to_free = nr_pages; + int priority; int i; for (priority = DEF_PRIORITY; priority; priority--) { @@ -712,13 +719,15 @@ static void kswapd_balance_pgdat(pg_data int to_reclaim; to_reclaim = zone->pages_high - zone->free_pages; + if (nr_pages && to_free > 0) + to_reclaim = min(to_free, SWAP_CLUSTER_MAX*8); if (to_reclaim <= 0) continue; success = 0; max_scan = zone->nr_inactive >> priority; if (max_scan < to_reclaim * 2) max_scan = to_reclaim * 2; - shrink_zone(zone, max_scan, GFP_KSWAPD, + to_free -= shrink_zone(zone, max_scan, GFP_KSWAPD, to_reclaim, &nr_mapped); shrink_slab(max_scan + nr_mapped, GFP_KSWAPD); } @@ -726,6 +735,7 @@ static void kswapd_balance_pgdat(pg_data break; /* All zones are at pages_high */ blk_congestion_wait(WRITE, HZ/4); } + return nr_pages - to_free; } /* @@ -772,10 +782,34 @@ int kswapd(void *p) prepare_to_wait(&pgdat->kswapd_wait, &wait, TASK_INTERRUPTIBLE); schedule(); finish_wait(&pgdat->kswapd_wait, &wait); - kswapd_balance_pgdat(pgdat); + balance_pgdat(pgdat, 0); blk_run_queues(); } } + +#ifdef CONFIG_SOFTWARE_SUSPEND +/* + * Try to free `nr_pages' of memory, system-wide. Returns the number of freed + * pages. + */ +int shrink_all_memory(int nr_pages) +{ + pg_data_t *pgdat; + int nr_to_free = nr_pages; + int ret = 0; + + for_each_pgdat(pgdat) { + int freed; + + freed = balance_pgdat(pgdat, nr_to_free); + ret += freed; + nr_to_free -= freed; + if (nr_to_free <= 0) + break; + } + return ret; +} +#endif static int __init kswapd_init(void) { --- 2.5.36/include/linux/swap.h~swsusp-feature Wed Sep 18 14:03:01 2002 +++ 2.5.36-akpm/include/linux/swap.h Wed Sep 18 14:16:29 2002 @@ -163,6 +163,7 @@ extern void swap_setup(void); /* linux/mm/vmscan.c */ extern int try_to_free_pages(struct zone *, unsigned int, unsigned int); +int shrink_all_memory(int nr_pages); /* linux/mm/page_io.c */ int swap_readpage(struct file *file, struct page *page); . -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/