On Wed, Aug 14, 2024 at 09:38:35PM +0100, David Howells wrote: > Make the netfs write-side routines use the new folio_queue struct to hold a > rolling buffer of folios, with the issuer adding folios at the tail and the > collector removing them from the head as they're processed instead of using > an xarray. > > This will allow a subsequent patch to simplify the write collector. > > The primary mark (as tested by folioq_is_marked()) is used to note if the > corresponding folio needs putting. > > Signed-off-by: David Howells <dhowells@xxxxxxxxxx> > cc: Jeff Layton <jlayton@xxxxxxxxxx> > cc: netfs@xxxxxxxxxxxxxxx > cc: linux-fsdevel@xxxxxxxxxxxxxxx > --- > fs/netfs/internal.h | 9 +++- > fs/netfs/misc.c | 76 ++++++++++++++++++++++++++++++++ > fs/netfs/objects.c | 1 + > fs/netfs/stats.c | 4 +- > fs/netfs/write_collect.c | 84 +++++++++++++++++++----------------- > fs/netfs/write_issue.c | 28 ++++++------ > include/linux/netfs.h | 8 ++-- > include/trace/events/netfs.h | 1 + > 8 files changed, 150 insertions(+), 61 deletions(-) According to git bisect, this commit causes to the following kernel splat during boot of the system with 9p fs. # # Caches # CONFIG_NETFS_SUPPORT=y # CONFIG_NETFS_STATS is not set # CONFIG_NETFS_DEBUG is not set # CONFIG_FSCACHE is not set # end of Caches ... CONFIG_9P_FS=y ... [ 1.510725][ T1] Run /sbin/init as init process [ 1.510937][ T1] with arguments: [ 1.511060][ T1] /sbin/init [ 1.511233][ T1] with environment: [ 1.511332][ T1] HOME=/ [ 1.511448][ T1] TERM=linux [ 1.516066][ T1] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6ce48 [ 1.516920][ T1] flags: 0x4000000000000000(zone=1) [ 1.517112][ T1] raw: 4000000000000000 ffffea0001b39248 ffffea00001583c8 0000000000000000 [ 1.517374][ T1] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 [ 1.517767][ T1] page dumped because: VM_BUG_ON_FOLIO(((unsigned int) folio_ref_count(folio) + 127u <= 127u)) [ 1.518144][ T1] ------------[ cut here ]------------ [ 1.518311][ T1] kernel BUG at include/linux/mm.h:1444! [ 1.518488][ T1] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN [ 1.518738][ T1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.11.0+ #2488 [ 1.518990][ T1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 1.519325][ T1] RIP: 0010:__iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.519540][ T1] Code: 84 f2 fa ff ff 48 89 ef e8 49 28 98 ff e9 e5 fa ff ff 48 8d 48 ff e9 2c fe ff ff 48 c7 c6 20 ee 21 83 48 89 cf e8 7c 2d 8a ff <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 8b 74 24 68 44 8b 5c 24 30 [ 1.520110][ T1] RSP: 0000:ffff8880060f6e40 EFLAGS: 00010286 [ 1.520317][ T1] RAX: 000000000000005c RBX: ffffea0001b39234 RCX: 0000000000000000 [ 1.520547][ T1] RDX: 000000000000005c RSI: 0000000000000004 RDI: ffffed1000c1edbb [ 1.520776][ T1] RBP: dffffc0000000000 R08: 0000000000000000 R09: fffffbfff0718ce0 [ 1.521027][ T1] R10: 0000000000000003 R11: 0000000000000001 R12: ffff8880065bd7e0 12:43:45 [122/ [ 1.521252][ T1] R13: ffff888006644000 R14: 0000000000000002 R15: 0000000000001000 [ 1.521475][ T1] FS: 0000000000000000(0000) GS:ffff88806ce80000(0000) knlGS:0000000000000000 [ 1.521761][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.521961][ T1] CR2: 0000000000000000 CR3: 0000000003881001 CR4: 0000000000370eb0 [ 1.522200][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1.522418][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1.522636][ T1] Call Trace: [ 1.522750][ T1] <TASK> [ 1.522823][ T1] ? __die+0x52/0x8f [ 1.522939][ T1] ? die+0x2a/0x50 [ 1.523061][ T1] ? do_trap+0x1d9/0x2c0 [ 1.523163][ T1] ? __iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.523334][ T1] ? do_error_trap+0xa3/0x160 [ 1.523465][ T1] ? __iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.523633][ T1] ? handle_invalid_op+0x2c/0x30 [ 1.523765][ T1] ? __iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.523942][ T1] ? exc_invalid_op+0x29/0x40 [ 1.524087][ T1] ? asm_exc_invalid_op+0x16/0x20 [ 1.524238][ T1] ? __iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.524426][ T1] ? iov_iter_extract_pages+0x1ee0/0x1ee0 [ 1.524575][ T1] ? radix_tree_node_alloc.constprop.0+0x16a/0x2c0 [ 1.524762][ T1] ? lock_acquire+0xe2/0x500 [ 1.524916][ T1] ? mark_lock+0xfc/0x2dc0 [ 1.525071][ T1] iov_iter_get_pages_alloc2+0x3d/0xe0 [ 1.525208][ T1] ? print_usage_bug.part.0+0x600/0x600 [ 1.525392][ T1] p9_get_mapped_pages.part.0.constprop.0+0x3bf/0x6c0 [ 1.525595][ T1] ? p9pdu_vwritef+0x320/0x1f20 [ 1.525756][ T1] ? p9_virtio_request+0x550/0x550 [ 1.525918][ T1] ? pdu_read+0xc0/0xc0 [ 1.526056][ T1] ? lock_release+0x220/0x780 [ 1.526218][ T1] ? pdu_read+0xc0/0xc0 [ 1.526341][ T1] p9_virtio_zc_request+0x728/0x1020 [ 1.526501][ T1] ? p9pdu_vwritef+0x320/0x1f20 [ 1.526662][ T1] ? p9_virtio_probe+0xa20/0xa20 [ 1.526824][ T1] ? netfs_read_to_pagecache+0x601/0xd50 [ 1.526990][ T1] ? mark_lock+0xfc/0x2dc0 [ 1.527159][ T1] ? p9pdu_finalize+0xdc/0x1d0 [ 1.527321][ T1] ? p9_client_prepare_req+0x235/0x360 [ 1.527483][ T1] ? p9_tag_alloc+0x6e0/0x6e0 [ 1.527644][ T1] ? lock_release+0x220/0x780 [ 1.527806][ T1] p9_client_zc_rpc.constprop.0+0x236/0x7d0 [ 1.528013][ T1] ? __create_object+0x5e/0x80 [ 1.528175][ T1] ? p9_client_flush.isra.0+0x390/0x390 [ 1.528345][ T1] ? lockdep_hardirqs_on_prepare+0x268/0x3e0 [ 1.528544][ T1] ? __call_rcu_common.constprop.0+0x475/0xc80 [ 1.528785][ T1] ? p9_req_put+0x17a/0x200 [ 1.528944][ T1] p9_client_read_once+0x343/0x840 [ 1.529114][ T1] ? p9_client_getlock_dotl+0x3c0/0x3c0 [ 1.529274][ T1] p9_client_read+0xf1/0x150 [ 1.529440][ T1] v9fs_issue_read+0x107/0x2c0 [ 1.529608][ T1] ? v9fs_issue_write+0x140/0x140 [ 1.529736][ T1] netfs_read_to_pagecache+0x601/0xd50 [ 1.529858][ T1] netfs_readahead+0x6af/0xbe0 [ 1.530000][ T1] read_pages+0x17b/0xaf0 [ 1.530136][ T1] ? lru_move_tail+0x8f0/0x8f0 [ 1.530299][ T1] ? file_ra_state_init+0xd0/0xd0 [ 1.530479][ T1] page_cache_ra_unbounded+0x324/0x5f0 [ 1.530638][ T1] filemap_get_pages+0x597/0x16b0 [ 1.530801][ T1] ? filemap_add_folio+0x140/0x140 [ 1.530957][ T1] ? lock_is_held_type+0x81/0xe0 [ 1.531121][ T1] filemap_read+0x2ec/0xa90 [ 1.531282][ T1] ? filemap_get_pages+0x16b0/0x16b0 [ 1.531443][ T1] ? 0xffffffff81000000 [ 1.531565][ T1] ? find_held_lock+0x2d/0x110 [ 1.531720][ T1] ? lock_is_held_type+0x81/0xe0 [ 1.531888][ T1] ? down_read_interruptible+0x1f6/0x490 [ 1.532062][ T1] ? down_read+0x450/0x450 [ 1.532229][ T1] ? lockdep_hardirqs_on_prepare+0x3e0/0x3e0 [ 1.532435][ T1] ? find_held_lock+0x2d/0x110 [ 1.532594][ T1] netfs_buffered_read_iter+0xe2/0x130 [ 1.532755][ T1] ? netfs_file_read_iter+0xb2/0x130 [ 1.532904][ T1] __kernel_read+0x2db/0x8a0 [ 1.533066][ T1] ? __x64_sys_lseek+0x1d0/0x1d0 [ 1.533221][ T1] bprm_execve+0x548/0x1410 [ 1.533381][ T1] ? setup_arg_pages+0xb40/0xb40 [ 1.533534][ T1] ? __cond_resched+0x17/0x70 [ 1.533684][ T1] kernel_execve+0x26a/0x2f0 [ 1.533808][ T1] try_to_run_init_process+0xf/0x30 [ 1.533933][ T1] ? rest_init+0x1b0/0x1b0 [ 1.534064][ T1] kernel_init+0xe2/0x140 [ 1.534160][ T1] ? _raw_spin_unlock_irq+0x24/0x30 [ 1.534285][ T1] ret_from_fork+0x2d/0x70 [ 1.534415][ T1] ? rest_init+0x1b0/0x1b0 [ 1.534558][ T1] ret_from_fork_asm+0x11/0x20 [ 1.534730][ T1] </TASK> [ 1.534858][ T1] Modules linked in: [ 1.535016][ T1] ---[ end trace 0000000000000000 ]--- [ 1.535173][ T1] RIP: 0010:__iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.535385][ T1] Code: 84 f2 fa ff ff 48 89 ef e8 49 28 98 ff e9 e5 fa ff ff 48 8d 48 ff e9 2c fe ff ff 48 c7 c6 20 ee 21 83 48 89 cf e8 7c 2d 8a ff <0f> 0b 48 b8 00 00 00 00 00 fc ff df 4c 8b 74 24 68 44 8b 5c 24 30 [ 1.535967][ T1] RSP: 0000:ffff8880060f6e40 EFLAGS: 00010286 [ 1.536183][ T1] RAX: 000000000000005c RBX: ffffea0001b39234 RCX: 0000000000000000 [ 1.536426][ T1] RDX: 000000000000005c RSI: 0000000000000004 RDI: ffffed1000c1edbb [ 1.536667][ T1] RBP: dffffc0000000000 R08: 0000000000000000 R09: fffffbfff0718ce0 [ 1.536914][ T1] R10: 0000000000000003 R11: 0000000000000001 R12: ffff8880065bd7e0 [ 1.537163][ T1] R13: ffff888006644000 R14: 0000000000000002 R15: 0000000000001000 [ 1.537409][ T1] FS: 0000000000000000(0000) GS:ffff88806ce80000(0000) knlGS:0000000000000000 [ 1.537842][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.538035][ T1] CR2: 0000000000000000 CR3: 0000000003881001 CR4: 0000000000370eb0 [ 1.538281][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1.538519][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1.538779][ T1] ------------[ cut here ]------------ [ 1.538904][ T1] WARNING: CPU: 1 PID: 1 at kernel/exit.c:886 do_exit+0x17c4/0x23a0 [ 1.539110][ T1] Modules linked in: [ 1.539229][ T1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Tainted: G D 6.11.0+ #2488 [ 1.539459][ T1] Tainted: [D]=DIE [ 1.539567][ T1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 [ 1.539860][ T1] RIP: 0010:do_exit+0x17c4/0x23a0 [ 1.540008][ T1] Code: bb 68 04 00 00 31 f6 e8 5a 92 ff ff e9 d6 f8 ff ff 4c 89 fe bf 05 06 00 00 e8 c8 53 02 00 e9 5c ec ff ff 0f 0b e9 b7 e8 ff ff <0f> 0b e9 27 ea ff ff 48 89 df e8 ad 90 ff ff 48 85 c0 49 89 c7 0f [ 1.540502][ T1] RSP: 0000:ffff8880060f7e68 EFLAGS: 00010286 [ 1.540657][ T1] RAX: dffffc0000000000 RBX: ffff8880060e8000 RCX: 1ffffffff07aebdf [ 1.540860][ T1] RDX: 1ffff11000c1d20b RSI: 0000000000000008 RDI: ffff8880060e9058 [ 1.541078][ T1] RBP: ffff8880060e8708 R08: 0000000000000000 R09: fffffbfff07ae5c1 [ 1.541261][ T1] R10: 0000000000000000 R11: 0000000000000001 R12: ffff888006108000 [ 1.541437][ T1] R13: ffff8880060e8710 R14: ffff888006100000 R15: 000000000000000b [ 1.541645][ T1] FS: 0000000000000000(0000) GS:ffff88806ce80000(0000) knlGS:0000000000000000 [ 1.541875][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.542043][ T1] CR2: 0000000000000000 CR3: 0000000003881001 CR4: 0000000000370eb0 [ 1.542237][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1.542432][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1.542622][ T1] Call Trace: [ 1.542733][ T1] <TASK> [ 1.542801][ T1] ? __warn.cold+0x5f/0x1ed [ 1.542930][ T1] ? do_exit+0x17c4/0x23a0 [ 1.543063][ T1] ? report_bug+0x1e6/0x290 [ 1.543190][ T1] ? handle_bug+0x4f/0x90 [ 1.543290][ T1] ? exc_invalid_op+0x13/0x40 [ 1.543418][ T1] ? asm_exc_invalid_op+0x16/0x20 [ 1.543545][ T1] ? do_exit+0x17c4/0x23a0 [ 1.543676][ T1] ? do_exit+0x1c2/0x23a0 [ 1.543774][ T1] ? __cond_resched+0x17/0x70 [ 1.543904][ T1] ? is_current_pgrp_orphaned+0x90/0x90 [ 1.544040][ T1] ? kernel_execve+0x26a/0x2f0 [ 1.544169][ T1] ? __iov_iter_get_pages_alloc+0x16d4/0x2210 [ 1.544329][ T1] make_task_dead+0xf0/0x110 [ 1.544462][ T1] rewind_stack_and_make_dead+0x16/0x20 [ 1.544595][ T1] RIP: 0000:0x0 [ 1.544708][ T1] Code: Unable to access opcode bytes at 0xffffffffffffffd6. [ 1.544903][ T1] RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 [ 1.545098][ T1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 1.545286][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 1.545489][ T1] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 1.545699][ T1] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 1.545898][ T1] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 1.546099][ T1] </TASK> [ 1.546198][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ... [ 1.546654][ T1] Kernel Offset: disabled [ 1.546769][ T1] ---[ end Kernel panic - not syncing: kernel: panic_on_warn set ... ]--- Thanks
