| Message ID | 164859751830.29473.5309689752169286816.stgit@noble.brown (mailing list archive) |
|---|---|
| Headers | show |
| Series | MM changes to improve swap-over-NFS support | expand |
Do you have a branch with your patches on? David
On Wed, 30 Mar 2022, David Howells wrote:
> Do you have a branch with your patches on?
http://git.neil.brown.name/?p=linux.git;a=shortlog;h=refs/heads/swap-nfs
git://neil.brown.name/linux branch swap-nfs
Also on https://github.com/neilbrown/linux.git same branch
(it seems 1GB is no longer enough to run a git server for the kernel
effectively)
This contains
- recent HEAD from Linus, which includes the NFS work
- the patches I sent to akpm
- the patch to switch NFS over to using the new swap_rw
- a SUNRPC patch to fix an easy crash. But has always been there,
but recent changes to how kmalloc is called makes it much easier to
trigger.
NeilBrown
NeilBrown <neilb@suse.de> wrote: > Assorted improvements for swap-via-filesystem. > > This is a resend of these patches, rebased on current HEAD. > The only substantial changes is that swap_dirty_folio has replaced > swap_set_page_dirty. > > Currently swap-via-fs (SWP_FS_OPS) doesn't work for any filesystem. It > has previously worked for NFS but that broke a few releases back. > This series changes to use a new ->swap_rw rather than ->readpage and > ->direct_IO. It also makes other improvements. > > There is a companion series already in linux-next which fixes various > issues with NFS. Once both series land, a final patch is needed which > changes NFS over to use ->swap_rw. This seems to work by running sufficient copies of the attached program in parallel to overwhelm the amount of ordinary RAM. Tested-by: David Howells <dhowells@redhat.com> --- #include <stdbool.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/mman.h> int main() { unsigned int pid = getpid(), iterations = 0; size_t i, j, size = 1024 * 1024 * 1024; char *p; bool mismatch; p = malloc(size); if (!p) { perror("malloc"); exit(1); } srand(pid); for (i = 0; i < size; i += 4) *(unsigned int *)(p + i) = rand(); do { for (j = 0; j < 16; j++) { for (i = 0; i < size; i += 4096) *(unsigned int *)(p + i) += 1; iterations++; } mismatch = false; srand(pid); for (i = 0; i < size; i += 4) { unsigned int r = rand(); unsigned int v = *(unsigned int *)(p + i); if (i % 4096 == 0) v -= iterations; if (v != r) { fprintf(stderr, "mismatch %zx: %x != %x (diff %x)\n", i, v, r, v - r); mismatch = true; } } } while (!mismatch); exit(1); }
Hi Neil, On Thu, Mar 31, 2022 at 4:54 AM NeilBrown <neilb@suse.de> wrote: > On Wed, 30 Mar 2022, David Howells wrote: > > Do you have a branch with your patches on? > > http://git.neil.brown.name/?p=linux.git;a=shortlog;h=refs/heads/swap-nfs > > git://neil.brown.name/linux branch swap-nfs > > Also on https://github.com/neilbrown/linux.git same branch > > (it seems 1GB is no longer enough to run a git server for the kernel > effectively) > > This contains > - recent HEAD from Linus, which includes the NFS work > - the patches I sent to akpm > - the patch to switch NFS over to using the new swap_rw > - a SUNRPC patch to fix an easy crash. But has always been there, > but recent changes to how kmalloc is called makes it much easier to > trigger. Thanks for your series! I gave this a try on Renesas RSK+RZA1 (RZ/A1H with 32 MiB of RAM) and RZA2MEVB (RZ/A2M with 64 MiB of RAM) with a Debian nfsroot. Seems to work, so Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> However, I still managed to trigger memory allocation failures, even on the RZ/A2, which I don't remember seeing last time I tried. root@rza2mevb:~# free total used free shared buff/cache available Mem: 57428 12400 20024 1212 25004 40028 Swap: 0 0 0 root@rza2mevb:~# swapon /swap Adding 1048572k swap on /swap. Priority:-2 extents:1 across:1048572k root@rza2mevb:~# apt update Ign:1 http://ftp.be.debian.org/debian stretch InRelease Get:2 http://security.debian.org stretch/updates InRelease [53.0 kB] Hit:3 http://ftp.be.debian.org/debian stretch Release Get:5 http://security.debian.org stretch/updates/main armhf Packages [738 kB] Get:6 http://security.debian.org stretch/updates/main Translation-en [356 kB] Fetched 1,147 kB in 12s (89.5 kB/s) apt: page allocation failure: order:0, mode:0x40cc0(GFP_KERNEL|__GFP_COMP), nodemask=(null) CPU: 0 PID: 455 Comm: apt Not tainted 5.18.0-rc3-rza2mevb-00734-g98e2a6b7a591 #186 Hardware name: Generic R7S9210 (Flattened Device Tree) unwind_backtrace from show_stack+0x10/0x14 show_stack from warn_alloc+0xa0/0x150 warn_alloc from __alloc_pages+0x3a0/0x8c0 __alloc_pages from ____cache_alloc+0x194/0x734 ____cache_alloc from kmem_cache_alloc+0x60/0xd0 kmem_cache_alloc from nfs_writehdr_alloc+0x28/0x70 nfs_writehdr_alloc from nfs_pgio_header_alloc+0x10/0x28 nfs_pgio_header_alloc from nfs_generic_pg_pgios+0x14/0xa8 nfs_generic_pg_pgios from nfs_pageio_doio+0x2c/0x4c nfs_pageio_doio from __nfs_pageio_add_request+0x34c/0x3c8 __nfs_pageio_add_request from nfs_pageio_add_request_mirror+0x18/0x44 nfs_pageio_add_request_mirror from nfs_pageio_add_request+0x1b8/0x1c8 nfs_pageio_add_request from nfs_direct_write_schedule_iovec+0x208/0x28c nfs_direct_write_schedule_iovec from nfs_file_direct_write+0x128/0x21c nfs_file_direct_write from nfs_swap_rw+0x24/0x28 nfs_swap_rw from swap_write_unplug+0x54/0x94 swap_write_unplug from __swap_writepage+0x10c/0x20c __swap_writepage from shrink_page_list+0x86c/0xabc shrink_page_list from shrink_inactive_list+0xfc/0x2b0 shrink_inactive_list from shrink_node+0x598/0x80c shrink_node from try_to_free_pages+0x2bc/0x3e8 try_to_free_pages from __alloc_pages+0x55c/0x8c0 __alloc_pages from __filemap_get_folio+0x1b4/0x260 __filemap_get_folio from pagecache_get_page+0x10/0x68 pagecache_get_page from nfs_write_begin+0x30/0x148 nfs_write_begin from generic_perform_write+0xa4/0x1b8 generic_perform_write from nfs_file_write+0xf0/0x2a4 nfs_file_write from vfs_write+0x140/0x19c vfs_write from ksys_write+0x74/0xc8 ksys_write from ret_fast_syscall+0x0/0x54 Exception stack(0xc4c1dfa8 to 0xc4c1dff0) dfa0: b6ec4025 00000000 00000004 b1d0e000 019f12ac befee52c dfc0: b6ec4025 00000000 019f12ac 00000004 019f12ac b1d0e000 befee52c befee7ac dfe0: 00000000 befee4d4 b6ec0b43 b6cb1cf6 Mem-Info: active_anon:1772 inactive_anon:7471 isolated_anon:64 active_file:679 inactive_file:392 isolated_file:0 unevictable:0 dirty:0 writeback:2891 slab_reclaimable:417 slab_unreclaimable:2863 mapped:32 shmem:52 pagetables:107 bounce:0 kernel_misc_reclaimable:0 free:0 free_pcp:6 free_cma:0 Node 0 active_anon:7088kB inactive_anon:29884kB active_file:2716kB inactive_file:1568kB unevictable:0kB isolated(anon):256kB isolated(file):0kB mapped:128kB dirty:0kB writeback:11564kB shmem:208kB writeback_tmp:0kB kernel_stack:408kB pagetables:428kB all_unreclaimable? no Normal free:0kB boost:4096kB min:5044kB low:5280kB high:5516kB reserved_highatomic:0KB active_anon:7088kB inactive_anon:29884kB active_file:2716kB inactive_file:1568kB unevictable:0kB writepending:10296kB present:65536kB managed:57428kB mlocked:0kB bounce:0kB free_pcp:24kB local_pcp:24kB free_cma:0kB lowmem_reserve[]: 0 0 Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 0kB 7385 total pagecache pages 6262 pages in swap cache Swap cache stats: add 6787, delete 525, find 58/74 Free swap = 1021476kB Total swap = 1048572kB 16384 pages RAM 0 pages HighMem/MovableOnly 2027 pages reserved Write error -12 on dio swapfile (27660288) Write error -12 on dio swapfile (29679616) Write error -12 on dio swapfile (8572928) Write error 0 on dio swapfile (8441856) Write error 0 on dio swapfile (8704000) Write error -12 on dio swapfile (8966144) Write error -12 on dio swapfile (9097216) Write error 0 on dio swapfile (8835072) Write error 0 on dio swapfile (9228288) Write error 0 on dio swapfile (9359360) sio_write_complete: 2731 callbacks suppressed Write error 0 on dio swapfile (34705408) Write error 0 on dio swapfile (23470080) Write error 0 on dio swapfile (23601152) Write error 0 on dio swapfile (23732224) Write error 0 on dio swapfile (4202496) Write error 0 on dio swapfile (4304896) Write error 0 on dio swapfile (4435968) Write error 0 on dio swapfile (4567040) Write error 0 on dio swapfile (4698112) Write error 0 on dio swapfile (4829184) warn_alloc: 125849 callbacks suppressed kworker/u2:7: page allocation failure: order:0, mode:0x60c40(GFP_NOFS|__GFP_COMP|__GFP_MEMALLOC), nodemask=(null) CPU: 0 PID: 457 Comm: kworker/u2:7 Not tainted 5.18.0-rc3-rza2mevb-00734-g98e2a6b7a591 #186 Hardware name: Generic R7S9210 (Flattened Device Tree) Workqueue: rpciod rpc_async_schedule unwind_backtrace from show_stack+0x10/0x14 show_stack from warn_alloc+0xa0/0x150 warn_alloc from __alloc_pages+0x3a0/0x8c0 __alloc_pages from ____cache_alloc+0x194/0x734 ____cache_alloc from __kmalloc_track_caller+0x74/0xf0 __kmalloc_track_caller from kmalloc_reserve.constprop.0+0x4c/0x60 kmalloc_reserve.constprop.0 from __alloc_skb+0x88/0x154 __alloc_skb from tcp_stream_alloc_skb+0x68/0x13c tcp_stream_alloc_skb from tcp_sendmsg_locked+0x4b8/0xabc tcp_sendmsg_locked from tcp_sendmsg+0x24/0x38 tcp_sendmsg from sock_sendmsg_nosec+0x14/0x24 sock_sendmsg_nosec from xprt_sock_sendmsg+0x1d8/0x244 xprt_sock_sendmsg from xs_tcp_send_request+0x11c/0x20c xs_tcp_send_request from xprt_transmit+0x84/0x234 xprt_transmit from call_transmit+0x6c/0x7c call_transmit from __rpc_execute+0xe4/0x2f0 __rpc_execute from rpc_async_schedule+0x18/0x24 rpc_async_schedule from process_one_work+0x170/0x210 process_one_work from worker_thread+0x204/0x2a4 worker_thread from kthread+0xb0/0xbc kthread from ret_from_fork+0x14/0x2c Exception stack(0xc4e0dfb0 to 0xc4e0dff8) dfa0: 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 Mem-Info: active_anon:2703 inactive_anon:6291 isolated_anon:209 active_file:541 inactive_file:530 isolated_file:0 unevictable:0 dirty:0 writeback:3781 slab_reclaimable:391 slab_unreclaimable:2993 mapped:0 shmem:0 pagetables:107 bounce:0 kernel_misc_reclaimable:0 free:0 free_pcp:26 free_cma:0 Node 0 active_anon:10812kB inactive_anon:25164kB active_file:2164kB inactive_file:2120kB unevictable:0kB isolated(anon):836kB isolated(file):0kB mapped:0kB dirty:0kB writeback:15124kB shmem:0kB writeback_tmp:0kB kernel_stack:408kB pagetables:428kB all_unreclaimable? yes Normal free:0kB boost:0kB min:948kB low:1184kB high:1420kB reserved_highatomic:0KB active_anon:10812kB inactive_anon:25164kB active_file:2164kB inactive_file:2120kB unevictable:0kB writepending:13284kB present:65536kB managed:57428kB mlocked:0kB bounce:0kB free_pcp:104kB local_pcp:104kB free_cma:0kB lowmem_reserve[]: 0 0 Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 0kB 10274 total pagecache pages 9203 pages in swap cache Swap cache stats: add 9834, delete 631, find 61/77 Free swap = 1009180kB Total swap = 1048572kB 16384 pages RAM 0 pages HighMem/MovableOnly 2027 pages reserved sio_write_complete: 29066 callbacks suppressed ... Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
On Wed, 20 Apr 2022, Geert Uytterhoeven wrote: > Hi Neil, > > On Thu, Mar 31, 2022 at 4:54 AM NeilBrown <neilb@suse.de> wrote: > > On Wed, 30 Mar 2022, David Howells wrote: > > > Do you have a branch with your patches on? > > > > http://git.neil.brown.name/?p=linux.git;a=shortlog;h=refs/heads/swap-nfs > > > > git://neil.brown.name/linux branch swap-nfs > > > > Also on https://github.com/neilbrown/linux.git same branch > > > > (it seems 1GB is no longer enough to run a git server for the kernel > > effectively) > > > > This contains > > - recent HEAD from Linus, which includes the NFS work > > - the patches I sent to akpm > > - the patch to switch NFS over to using the new swap_rw > > - a SUNRPC patch to fix an easy crash. But has always been there, > > but recent changes to how kmalloc is called makes it much easier to > > trigger. > > Thanks for your series! > > I gave this a try on Renesas RSK+RZA1 (RZ/A1H with 32 MiB of RAM) > and RZA2MEVB (RZ/A2M with 64 MiB of RAM) with a Debian nfsroot. > Seems to work, so > Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Thanks for testing!!!! > > However, I still managed to trigger memory allocation failures, > even on the RZ/A2, which I don't remember seeing last time I tried. > > root@rza2mevb:~# free > total used free shared buff/cache available > Mem: 57428 12400 20024 1212 25004 40028 > Swap: 0 0 0 > root@rza2mevb:~# swapon /swap > Adding 1048572k swap on /swap. Priority:-2 extents:1 across:1048572k > root@rza2mevb:~# apt update > Ign:1 http://ftp.be.debian.org/debian stretch InRelease > Get:2 http://security.debian.org stretch/updates InRelease [53.0 kB] > Hit:3 http://ftp.be.debian.org/debian stretch Release > Get:5 http://security.debian.org stretch/updates/main armhf Packages [738 kB] > Get:6 http://security.debian.org stretch/updates/main Translation-en [356 kB] > Fetched 1,147 kB in 12s (89.5 kB/s) > apt: page allocation failure: order:0, > mode:0x40cc0(GFP_KERNEL|__GFP_COMP), nodemask=(null) > CPU: 0 PID: 455 Comm: apt Not tainted > 5.18.0-rc3-rza2mevb-00734-g98e2a6b7a591 #186 > Hardware name: Generic R7S9210 (Flattened Device Tree) > unwind_backtrace from show_stack+0x10/0x14 > show_stack from warn_alloc+0xa0/0x150 > warn_alloc from __alloc_pages+0x3a0/0x8c0 > __alloc_pages from ____cache_alloc+0x194/0x734 > ____cache_alloc from kmem_cache_alloc+0x60/0xd0 > kmem_cache_alloc from nfs_writehdr_alloc+0x28/0x70 > nfs_writehdr_alloc from nfs_pgio_header_alloc+0x10/0x28 This is due to a recent change in NFS code which I don't think actually makes sense. Commit 0bae835b63c5 ("NFS: Avoid writeback threads getting stuck in mempool_alloc()") I need to find an alternate approach which addresses Trond's concerns but also works. I'm just now back from leave and will try to look at this over the next week or two. Thanks, NeilBrown > nfs_pgio_header_alloc from nfs_generic_pg_pgios+0x14/0xa8 > nfs_generic_pg_pgios from nfs_pageio_doio+0x2c/0x4c > nfs_pageio_doio from __nfs_pageio_add_request+0x34c/0x3c8 > __nfs_pageio_add_request from nfs_pageio_add_request_mirror+0x18/0x44 > nfs_pageio_add_request_mirror from nfs_pageio_add_request+0x1b8/0x1c8 > nfs_pageio_add_request from nfs_direct_write_schedule_iovec+0x208/0x28c > nfs_direct_write_schedule_iovec from nfs_file_direct_write+0x128/0x21c > nfs_file_direct_write from nfs_swap_rw+0x24/0x28 > nfs_swap_rw from swap_write_unplug+0x54/0x94 > swap_write_unplug from __swap_writepage+0x10c/0x20c > __swap_writepage from shrink_page_list+0x86c/0xabc > shrink_page_list from shrink_inactive_list+0xfc/0x2b0 > shrink_inactive_list from shrink_node+0x598/0x80c > shrink_node from try_to_free_pages+0x2bc/0x3e8 > try_to_free_pages from __alloc_pages+0x55c/0x8c0 > __alloc_pages from __filemap_get_folio+0x1b4/0x260 > __filemap_get_folio from pagecache_get_page+0x10/0x68 > pagecache_get_page from nfs_write_begin+0x30/0x148 > nfs_write_begin from generic_perform_write+0xa4/0x1b8 > generic_perform_write from nfs_file_write+0xf0/0x2a4 > nfs_file_write from vfs_write+0x140/0x19c > vfs_write from ksys_write+0x74/0xc8 > ksys_write from ret_fast_syscall+0x0/0x54 > Exception stack(0xc4c1dfa8 to 0xc4c1dff0) > dfa0: b6ec4025 00000000 00000004 b1d0e000 019f12ac befee52c > dfc0: b6ec4025 00000000 019f12ac 00000004 019f12ac b1d0e000 befee52c befee7ac > dfe0: 00000000 befee4d4 b6ec0b43 b6cb1cf6 > Mem-Info: > active_anon:1772 inactive_anon:7471 isolated_anon:64 > active_file:679 inactive_file:392 isolated_file:0 > unevictable:0 dirty:0 writeback:2891 > slab_reclaimable:417 slab_unreclaimable:2863 > mapped:32 shmem:52 pagetables:107 bounce:0 > kernel_misc_reclaimable:0 > free:0 free_pcp:6 free_cma:0 > Node 0 active_anon:7088kB inactive_anon:29884kB active_file:2716kB > inactive_file:1568kB unevictable:0kB isolated(anon):256kB > isolated(file):0kB mapped:128kB dirty:0kB writeback:11564kB > shmem:208kB writeback_tmp:0kB kernel_stack:408kB pagetables:428kB > all_unreclaimable? no > Normal free:0kB boost:4096kB min:5044kB low:5280kB high:5516kB > reserved_highatomic:0KB active_anon:7088kB inactive_anon:29884kB > active_file:2716kB inactive_file:1568kB unevictable:0kB > writepending:10296kB present:65536kB managed:57428kB mlocked:0kB > bounce:0kB free_pcp:24kB local_pcp:24kB free_cma:0kB > lowmem_reserve[]: 0 0 > Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB > 0*1024kB 0*2048kB 0*4096kB = 0kB > 7385 total pagecache pages > 6262 pages in swap cache > Swap cache stats: add 6787, delete 525, find 58/74 > Free swap = 1021476kB > Total swap = 1048572kB > 16384 pages RAM > 0 pages HighMem/MovableOnly > 2027 pages reserved > Write error -12 on dio swapfile (27660288) > Write error -12 on dio swapfile (29679616) > Write error -12 on dio swapfile (8572928) > Write error 0 on dio swapfile (8441856) > Write error 0 on dio swapfile (8704000) > Write error -12 on dio swapfile (8966144) > Write error -12 on dio swapfile (9097216) > Write error 0 on dio swapfile (8835072) > Write error 0 on dio swapfile (9228288) > Write error 0 on dio swapfile (9359360) > sio_write_complete: 2731 callbacks suppressed > Write error 0 on dio swapfile (34705408) > Write error 0 on dio swapfile (23470080) > Write error 0 on dio swapfile (23601152) > Write error 0 on dio swapfile (23732224) > Write error 0 on dio swapfile (4202496) > Write error 0 on dio swapfile (4304896) > Write error 0 on dio swapfile (4435968) > Write error 0 on dio swapfile (4567040) > Write error 0 on dio swapfile (4698112) > Write error 0 on dio swapfile (4829184) > warn_alloc: 125849 callbacks suppressed > kworker/u2:7: page allocation failure: order:0, > mode:0x60c40(GFP_NOFS|__GFP_COMP|__GFP_MEMALLOC), nodemask=(null) > CPU: 0 PID: 457 Comm: kworker/u2:7 Not tainted > 5.18.0-rc3-rza2mevb-00734-g98e2a6b7a591 #186 > Hardware name: Generic R7S9210 (Flattened Device Tree) > Workqueue: rpciod rpc_async_schedule > unwind_backtrace from show_stack+0x10/0x14 > show_stack from warn_alloc+0xa0/0x150 > warn_alloc from __alloc_pages+0x3a0/0x8c0 > __alloc_pages from ____cache_alloc+0x194/0x734 > ____cache_alloc from __kmalloc_track_caller+0x74/0xf0 > __kmalloc_track_caller from kmalloc_reserve.constprop.0+0x4c/0x60 > kmalloc_reserve.constprop.0 from __alloc_skb+0x88/0x154 > __alloc_skb from tcp_stream_alloc_skb+0x68/0x13c > tcp_stream_alloc_skb from tcp_sendmsg_locked+0x4b8/0xabc > tcp_sendmsg_locked from tcp_sendmsg+0x24/0x38 > tcp_sendmsg from sock_sendmsg_nosec+0x14/0x24 > sock_sendmsg_nosec from xprt_sock_sendmsg+0x1d8/0x244 > xprt_sock_sendmsg from xs_tcp_send_request+0x11c/0x20c > xs_tcp_send_request from xprt_transmit+0x84/0x234 > xprt_transmit from call_transmit+0x6c/0x7c > call_transmit from __rpc_execute+0xe4/0x2f0 > __rpc_execute from rpc_async_schedule+0x18/0x24 > rpc_async_schedule from process_one_work+0x170/0x210 > process_one_work from worker_thread+0x204/0x2a4 > worker_thread from kthread+0xb0/0xbc > kthread from ret_from_fork+0x14/0x2c > Exception stack(0xc4e0dfb0 to 0xc4e0dff8) > dfa0: 00000000 00000000 00000000 00000000 > dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 > Mem-Info: > active_anon:2703 inactive_anon:6291 isolated_anon:209 > active_file:541 inactive_file:530 isolated_file:0 > unevictable:0 dirty:0 writeback:3781 > slab_reclaimable:391 slab_unreclaimable:2993 > mapped:0 shmem:0 pagetables:107 bounce:0 > kernel_misc_reclaimable:0 > free:0 free_pcp:26 free_cma:0 > Node 0 active_anon:10812kB inactive_anon:25164kB active_file:2164kB > inactive_file:2120kB unevictable:0kB isolated(anon):836kB > isolated(file):0kB mapped:0kB dirty:0kB writeback:15124kB shmem:0kB > writeback_tmp:0kB kernel_stack:408kB pagetables:428kB > all_unreclaimable? yes > Normal free:0kB boost:0kB min:948kB low:1184kB high:1420kB > reserved_highatomic:0KB active_anon:10812kB inactive_anon:25164kB > active_file:2164kB inactive_file:2120kB unevictable:0kB > writepending:13284kB present:65536kB managed:57428kB mlocked:0kB > bounce:0kB free_pcp:104kB local_pcp:104kB free_cma:0kB > lowmem_reserve[]: 0 0 > Normal: 0*4kB 0*8kB 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB > 0*1024kB 0*2048kB 0*4096kB = 0kB > 10274 total pagecache pages > 9203 pages in swap cache > Swap cache stats: add 9834, delete 631, find 61/77 > Free swap = 1009180kB > Total swap = 1048572kB > 16384 pages RAM > 0 pages HighMem/MovableOnly > 2027 pages reserved > sio_write_complete: 29066 callbacks suppressed > ... > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds >
Assorted improvements for swap-via-filesystem. This is a resend of these patches, rebased on current HEAD. The only substantial changes is that swap_dirty_folio has replaced swap_set_page_dirty. Currently swap-via-fs (SWP_FS_OPS) doesn't work for any filesystem. It has previously worked for NFS but that broke a few releases back. This series changes to use a new ->swap_rw rather than ->readpage and ->direct_IO. It also makes other improvements. There is a companion series already in linux-next which fixes various issues with NFS. Once both series land, a final patch is needed which changes NFS over to use ->swap_rw. Thanks, NeilBrown --- NeilBrown (10): MM: create new mm/swap.h header file. MM: drop swap_dirty_folio MM: move responsibility for setting SWP_FS_OPS to ->swap_activate MM: reclaim mustn't enter FS for SWP_FS_OPS swap-space MM: introduce ->swap_rw and use it for reads from SWP_FS_OPS swap-space MM: perform async writes to SWP_FS_OPS swap-space using ->swap_rw DOC: update documentation for swap_activate and swap_rw MM: submit multipage reads for SWP_FS_OPS swap-space MM: submit multipage write for SWP_FS_OPS swap-space VFS: Add FMODE_CAN_ODIRECT file flag Documentation/filesystems/locking.rst | 18 +- Documentation/filesystems/vfs.rst | 17 +- drivers/block/loop.c | 4 +- fs/cifs/file.c | 7 +- fs/fcntl.c | 9 +- fs/nfs/file.c | 20 ++- fs/open.c | 9 +- fs/overlayfs/file.c | 13 +- include/linux/fs.h | 4 + include/linux/swap.h | 7 +- include/linux/writeback.h | 7 + mm/madvise.c | 8 +- mm/memory.c | 2 +- mm/page_io.c | 247 +++++++++++++++++++------- mm/swap.h | 30 +++- mm/swap_state.c | 22 ++- mm/swapfile.c | 13 +- mm/vmscan.c | 38 ++-- 18 files changed, 347 insertions(+), 128 deletions(-) -- Signature