I have a dual ppro 200MHZ W6LI motherboard. I put 2.4.4-ac5 on last
night, and the machine hung at Freeing unused Kernel memory. I
selectively backed off what I thought were relevant patches. I got to
aic7xxx, and ac5 without it worked. I attached /proc/scsi/aic7xxx/0.
Andy Carlson |\ _,,,---,,_
naclos@swbell.net ZZZzz /,`.-'`' -. ;-;;,_
BJC Health System |,4- ) )-,_. ,\ ( `'-'
St. Louis, Missouri '---''(_/--' `-'\_)
Cat Pics: http://andyc.dyndns.org
On Mon, 7 May 2001, Christoph Rohland wrote:
> Hi,
>
> The appended patch does it's own accounting of shmem pages and adjust
> the page cache size to take these into account. So now again you will
> see shmem pages as used in top/vmstat etc. This confused a lot of
> people.
>
> There is a uncertainty in the calculations since the vm may drop pages
> behind shmem and the number of shmem pages is estimated too high. This
> especially happens on truncate because first the page cache is reduced
> and later the shmem readjusts it's count.
>
> To prevent negative cache sizes the adjustment is only done if
> shmem_nrpages > page_cache_size.
>
> The latter part of the patch (all the init.c files) also exports the
> shmem page number to the shared memory field in meminfo. This means a
> change in semantics of this field but apparently a lot of people
> interpret this field exactly this way and it was not used any more
>
> The patches are on top of my encapsulation patch.
>
> Greetings
> Christoph
>
> diff -uNr 2.4.4-mSsu/fs/proc/proc_misc.c 2.4.4-mSsua/fs/proc/proc_misc.c
> --- 2.4.4-mSsu/fs/proc/proc_misc.c Sun Apr 29 20:32:52 2001
> +++ 2.4.4-mSsua/fs/proc/proc_misc.c Mon May 7 13:38:53 2001
> @@ -140,6 +140,17 @@
> {
> struct sysinfo i;
> int len;
> + unsigned int cached, shmem;
> +
> + /*
> + * There may be some inconsistency because shmem_nrpages
> + * update is delayed to page_cache_size
> + * We make sure the cached value does not get below zero
> + */
> + cached = atomic_read(&page_cache_size);
> + shmem = atomic_read(&shmem_nrpages);
> + if (shmem < cached)
> + cached -= shmem;
>
> /*
> * display in kilobytes.
> @@ -153,8 +164,8 @@
> "Swap: %8lu %8lu %8lu\n",
> B(i.totalram), B(i.totalram-i.freeram), B(i.freeram),
> B(i.sharedram), B(i.bufferram),
> - B(atomic_read(&page_cache_size)), B(i.totalswap),
> - B(i.totalswap-i.freeswap), B(i.freeswap));
> + B(cached), B(i.totalswap),
> + B(i.totalswap-i.freeswap), B(i.freeswap));
> /*
> * Tagged format, for easy grepping and expansion.
> * The above will go away eventually, once the tools
> @@ -180,7 +191,7 @@
> K(i.freeram),
> K(i.sharedram),
> K(i.bufferram),
> - K(atomic_read(&page_cache_size)),
> + K(cached),
> K(nr_active_pages),
> K(nr_inactive_dirty_pages),
> K(nr_inactive_clean_pages()),
> diff -uNr 2.4.4-mSsu/include/linux/shmem_fs.h 2.4.4-mSsua/include/linux/shmem_fs.h
> --- 2.4.4-mSsu/include/linux/shmem_fs.h Wed May 2 18:36:05 2001
> +++ 2.4.4-mSsua/include/linux/shmem_fs.h Mon May 7 12:52:00 2001
> @@ -17,6 +17,8 @@
> unsigned long val;
> } swp_entry_t;
>
> +extern atomic_t shmem_nrpages;
> +
> struct shmem_inode_info {
> spinlock_t lock;
> struct semaphore sem;
> diff -uNr 2.4.4-mSsu/mm/mmap.c 2.4.4-mSsua/mm/mmap.c
> --- 2.4.4-mSsu/mm/mmap.c Sun Apr 29 20:33:01 2001
> +++ 2.4.4-mSsua/mm/mmap.c Mon May 7 13:42:03 2001
> @@ -55,13 +55,24 @@
> */
>
> long free;
> -
> + unsigned long cached, shmem;
> +
> + /*
> + * There may be some inconsistency because shmem_nrpages
> + * update is delayed to the page_cache_size
> + * We make sure the cached value does not get below zero
> + */
> + cached = atomic_read(&page_cache_size);
> + shmem = atomic_read(&shmem_nrpages);
> + if (cached > shmem)
> + cached -= shmem;
> +
> /* Sometimes we want to use more memory than we have. */
> if (sysctl_overcommit_memory)
> return 1;
>
> free = atomic_read(&buffermem_pages);
> - free += atomic_read(&page_cache_size);
> + free += cached;
> free += nr_free_pages();
> free += nr_swap_pages;
>
> diff -uNr 2.4.4-mSsu/mm/shmem.c 2.4.4-mSsua/mm/shmem.c
> --- 2.4.4-mSsu/mm/shmem.c Fri May 4 21:37:34 2001
> +++ 2.4.4-mSsua/mm/shmem.c Mon May 7 11:13:27 2001
> @@ -3,7 +3,8 @@
> *
> * Copyright (C) 2000 Linus Torvalds.
> * 2000 Transmeta Corp.
> - * 2000 Christoph Rohland
> + * 2000-2001 Christoph Rohland
> + * 2000-2001 SAP AG
> *
> * This file is released under the GPL.
> */
> @@ -45,6 +46,7 @@
>
> LIST_HEAD (shmem_inodes);
> static spinlock_t shmem_ilock = SPIN_LOCK_UNLOCKED;
> +atomic_t shmem_nrpages = ATOMIC_INIT(0);
>
> #define BLOCKS_PER_PAGE (PAGE_SIZE/512)
>
> @@ -52,6 +54,7 @@
> * shmem_recalc_inode - recalculate the size of an inode
> *
> * @inode: inode to recalc
> + * @swap: additional swap pages freed externally
> *
> * We have to calculate the free blocks since the mm can drop pages
> * behind our back
> @@ -62,12 +65,14 @@
> *
> * So the mm freed
> * inodes->i_blocks/BLOCKS_PER_PAGE -
> - * (inode->i_mapping->nrpages + info->swapped)
> + * (inode->i_mapping->nrpages + info->swapped)
> *
> * It has to be called with the spinlock held.
> + *
> + * The swap parameter is a performance hack for truncate.
> */
>
> -static void shmem_recalc_inode(struct inode * inode)
> +static void shmem_recalc_inode(struct inode * inode, unsigned long swap)
> {
> unsigned long freed;
>
> @@ -79,6 +84,7 @@
> spin_lock (&info->stat_lock);
> info->free_blocks += freed;
> spin_unlock (&info->stat_lock);
> + atomic_sub(freed-swap, &shmem_nrpages);
> }
> }
>
> @@ -195,7 +201,7 @@
> out:
> info->max_index = index;
> info->swapped -= freed;
> - shmem_recalc_inode(inode);
> + shmem_recalc_inode(inode, freed);
> spin_unlock (&info->lock);
> up(&info->sem);
> }
> @@ -250,14 +256,15 @@
> entry = shmem_swp_entry(info, page->index);
> if (IS_ERR(entry)) /* this had been allocted on page allocation */
> BUG();
> - shmem_recalc_inode(page->mapping->host);
> + shmem_recalc_inode(page->mapping->host, 0);
> error = -EAGAIN;
> if (entry->val)
> BUG();
>
> *entry = swap;
> error = 0;
> - /* Remove the from the page cache */
> + /* Remove the page from the page cache */
> + atomic_dec(&shmem_nrpages);
> lru_cache_del(page);
> remove_inode_page(page);
>
> @@ -376,6 +383,7 @@
> }
>
> /* We have the page */
> + atomic_inc(&shmem_nrpages);
> SetPageUptodate(page);
> if (info->locked)
> page_cache_get(page);
> @@ -1275,6 +1283,7 @@
> return 0;
> found:
> add_to_page_cache(page, info->inode->i_mapping, offset + idx);
> + atomic_inc(&shmem_nrpages);
> set_page_dirty(page);
> SetPageUptodate(page);
> UnlockPage(page);
> diff -uNr 2.4.4-mSsu/arch/alpha/mm/init.c c/arch/alpha/mm/init.c
> --- 2.4.4-mSsu/arch/alpha/mm/init.c Sun Apr 29 20:31:56 2001
> +++ c/arch/alpha/mm/init.c Sun May 6 21:47:25 2001
> @@ -402,7 +402,7 @@
> si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/arm/mm/init.c c/arch/arm/mm/init.c
> --- 2.4.4-mSsu/arch/arm/mm/init.c Sun Apr 29 20:31:56 2001
> +++ c/arch/arm/mm/init.c Sun May 6 21:47:01 2001
> @@ -647,7 +647,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/cris/mm/init.c c/arch/cris/mm/init.c
> --- 2.4.4-mSsu/arch/cris/mm/init.c Sun Apr 29 20:31:57 2001
> +++ c/arch/cris/mm/init.c Sun May 6 21:47:03 2001
> @@ -503,7 +503,7 @@
>
> i = max_mapnr;
> val->totalram = 0;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> while (i-- > 0) {
> diff -uNr 2.4.4-mSsu/arch/i386/mm/init.c c/arch/i386/mm/init.c
> --- 2.4.4-mSsu/arch/i386/mm/init.c Sun Apr 29 20:32:08 2001
> +++ c/arch/i386/mm/init.c Sun May 6 20:24:21 2001
> @@ -570,7 +570,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = totalhigh_pages;
> diff -uNr 2.4.4-mSsu/arch/ia64/mm/init.c c/arch/ia64/mm/init.c
> --- 2.4.4-mSsu/arch/ia64/mm/init.c Sun Apr 29 20:32:11 2001
> +++ c/arch/ia64/mm/init.c Sun May 6 21:47:05 2001
> @@ -151,7 +151,7 @@
> si_meminfo (struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/m68k/mm/init.c c/arch/m68k/mm/init.c
> --- 2.4.4-mSsu/arch/m68k/mm/init.c Sat Nov 4 18:11:22 2000
> +++ c/arch/m68k/mm/init.c Sun May 6 21:47:45 2001
> @@ -217,7 +217,7 @@
>
> i = max_mapnr;
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> while (i-- > 0) {
> diff -uNr 2.4.4-mSsu/arch/mips/mm/init.c c/arch/mips/mm/init.c
> --- 2.4.4-mSsu/arch/mips/mm/init.c Sat Nov 4 18:11:22 2000
> +++ c/arch/mips/mm/init.c Sun May 6 21:47:01 2001
> @@ -343,7 +343,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/mips64/mm/init.c c/arch/mips64/mm/init.c
> --- 2.4.4-mSsu/arch/mips64/mm/init.c Sat Nov 4 18:11:22 2000
> +++ c/arch/mips64/mm/init.c Sun May 6 21:47:04 2001
> @@ -411,7 +411,7 @@
> si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/parisc/mm/init.c c/arch/parisc/mm/init.c
> --- 2.4.4-mSsu/arch/parisc/mm/init.c Sun Dec 17 12:53:55 2000
> +++ c/arch/parisc/mm/init.c Sun May 6 21:47:02 2001
> @@ -458,7 +458,7 @@
>
> i = max_mapnr;
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> #if 0
> diff -uNr 2.4.4-mSsu/arch/ppc/mm/init.c c/arch/ppc/mm/init.c
> --- 2.4.4-mSsu/arch/ppc/mm/init.c Wed Apr 11 12:36:13 2001
> +++ c/arch/ppc/mm/init.c Sun May 6 21:47:05 2001
> @@ -336,7 +336,7 @@
>
> i = max_mapnr;
> val->totalram = 0;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> while (i-- > 0) {
> diff -uNr 2.4.4-mSsu/arch/s390/mm/init.c c/arch/s390/mm/init.c
> --- 2.4.4-mSsu/arch/s390/mm/init.c Sun Apr 29 20:32:21 2001
> +++ c/arch/s390/mm/init.c Sun May 6 21:47:03 2001
> @@ -271,7 +271,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/s390x/mm/init.c c/arch/s390x/mm/init.c
> --- 2.4.4-mSsu/arch/s390x/mm/init.c Sun Apr 29 20:32:22 2001
> +++ c/arch/s390x/mm/init.c Sun May 6 21:47:18 2001
> @@ -284,7 +284,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = 0;
> diff -uNr 2.4.4-mSsu/arch/sh/mm/init.c c/arch/sh/mm/init.c
> --- 2.4.4-mSsu/arch/sh/mm/init.c Sun Apr 29 20:32:23 2001
> +++ c/arch/sh/mm/init.c Sun May 6 21:47:26 2001
> @@ -215,7 +215,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = totalhigh_pages;
> diff -uNr 2.4.4-mSsu/arch/sparc/mm/init.c c/arch/sparc/mm/init.c
> --- 2.4.4-mSsu/arch/sparc/mm/init.c Sun Apr 29 20:32:23 2001
> +++ c/arch/sparc/mm/init.c Sun May 6 21:47:04 2001
> @@ -534,7 +534,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = totalram_pages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
> val->totalhigh = totalhigh_pages;
> diff -uNr 2.4.4-mSsu/arch/sparc64/mm/init.c c/arch/sparc64/mm/init.c
> --- 2.4.4-mSsu/arch/sparc64/mm/init.c Sun Apr 29 20:32:25 2001
> +++ c/arch/sparc64/mm/init.c Sun May 6 21:47:02 2001
> @@ -1512,7 +1512,7 @@
> void si_meminfo(struct sysinfo *val)
> {
> val->totalram = num_physpages;
> - val->sharedram = 0;
> + val->sharedram = atomic_read(&shmem_nrpages);
> val->freeram = nr_free_pages();
> val->bufferram = atomic_read(&buffermem_pages);
>
>
> -
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This archive was generated by hypermail 2b29 : Mon May 07 2001 - 21:00:24 EST