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2024-02-16x86/resctrl: Allow RMID allocation to be scoped by CLOSIDJames Morse
MPAMs RMID values are not unique unless the CLOSID is considered as well. alloc_rmid() expects the RMID to be an independent number. Pass the CLOSID in to alloc_rmid(). Use this to compare indexes when allocating. If the CLOSID is not relevant to the index, this ends up comparing the free RMID with itself, and the first free entry will be used. With MPAM the CLOSID is included in the index, so this becomes a walk of the free RMID entries, until one that matches the supplied CLOSID is found. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-8-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Access per-rmid structures by indexJames Morse
x86 systems identify traffic using the CLOSID and RMID. The CLOSID is used to lookup the control policy, the RMID is used for monitoring. For x86 these are independent numbers. Arm's MPAM has equivalent features PARTID and PMG, where the PARTID is used to lookup the control policy. The PMG in contrast is a small number of bits that are used to subdivide PARTID when monitoring. The cache-occupancy monitors require the PARTID to be specified when monitoring. This means MPAM's PMG field is not unique. There are multiple PMG-0, one per allocated CLOSID/PARTID. If PMG is treated as equivalent to RMID, it cannot be allocated as an independent number. Bitmaps like rmid_busy_llc need to be sized by the number of unique entries for this resource. Treat the combined CLOSID and RMID as an index, and provide architecture helpers to pack and unpack an index. This makes the MPAM values unique. The domain's rmid_busy_llc and rmid_ptrs[] are then sized by index, as are domain mbm_local[] and mbm_total[]. x86 can ignore the CLOSID field when packing and unpacking an index, and report as many indexes as RMID. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-7-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Track the closid with the rmidJames Morse
x86's RMID are independent of the CLOSID. An RMID can be allocated, used and freed without considering the CLOSID. MPAM's equivalent feature is PMG, which is not an independent number, it extends the CLOSID/PARTID space. For MPAM, only PMG-bits worth of 'RMID' can be allocated for a single CLOSID. i.e. if there is 1 bit of PMG space, then each CLOSID can have two monitor groups. To allow resctrl to disambiguate RMID values for different CLOSID, everything in resctrl that keeps an RMID value needs to know the CLOSID too. This will always be ignored on x86. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Xin Hao <xhao@linux.alibaba.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-6-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Move RMID allocation out of mkdir_rdt_prepare()James Morse
RMIDs are allocated for each monitor or control group directory, because each of these needs its own RMID. For control groups, rdtgroup_mkdir_ctrl_mon() later goes on to allocate the CLOSID. MPAM's equivalent of RMID is not an independent number, so can't be allocated until the CLOSID is known. An RMID allocation for one CLOSID may fail, whereas another may succeed depending on how many monitor groups a control group has. The RMID allocation needs to move to be after the CLOSID has been allocated. Move the RMID allocation out of mkdir_rdt_prepare() to occur in its caller, after the mkdir_rdt_prepare() call. This allows the RMID allocator to know the CLOSID. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-5-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Create helper for RMID allocation and mondata dir creationJames Morse
When monitoring is supported, each monitor and control group is allocated an RMID. For control groups, rdtgroup_mkdir_ctrl_mon() later goes on to allocate the CLOSID. MPAM's equivalent of RMID are not an independent number, so can't be allocated until the CLOSID is known. An RMID allocation for one CLOSID may fail, whereas another may succeed depending on how many monitor groups a control group has. The RMID allocation needs to move to be after the CLOSID has been allocated. Move the RMID allocation and mondata dir creation to a helper. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Babu Moger <babu.moger@amd.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-4-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16x86/resctrl: Free rmid_ptrs from resctrl_exit()James Morse
rmid_ptrs[] is allocated from dom_data_init() but never free()d. While the exit text ends up in the linker script's DISCARD section, the direction of travel is for resctrl to be/have loadable modules. Add resctrl_put_mon_l3_config() to cleanup any memory allocated by rdt_get_mon_l3_config(). There is no reason to backport this to a stable kernel. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-3-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-02-16tick/nohz: Move tick_nohz_full_mask declaration outside the #ifdefJames Morse
tick_nohz_full_mask lists the CPUs that are nohz_full. This is only needed when CONFIG_NO_HZ_FULL is defined. tick_nohz_full_cpu() allows a specific CPU to be tested against the mask, and evaluates to false when CONFIG_NO_HZ_FULL is not defined. The resctrl code needs to pick a CPU to run some work on, a new helper prefers housekeeping CPUs by examining the tick_nohz_full_mask. Hiding the declaration behind #ifdef CONFIG_NO_HZ_FULL forces all the users to be behind an #ifdef too. Move the tick_nohz_full_mask declaration, this lets callers drop the #ifdef, and guard access to tick_nohz_full_mask with IS_ENABLED() or something like tick_nohz_full_cpu(). The definition does not need to be moved as any callers should be removed at compile time unless CONFIG_NO_HZ_FULL is defined. Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Reinette Chatre <reinette.chatre@intel.com> # for resctrl dependency Tested-by: Shaopeng Tan <tan.shaopeng@fujitsu.com> Tested-by: Peter Newman <peternewman@google.com> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64 Link: https://lore.kernel.org/r/20240213184438.16675-2-james.morse@arm.com Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
2024-01-25x86/resctrl: Remove redundant variable in mbm_config_write_domain()Babu Moger
The kernel test robot reported the following warning after commit 54e35eb8611c ("x86/resctrl: Read supported bandwidth sources from CPUID"). even though the issue is present even in the original commit 92bd5a139033 ("x86/resctrl: Add interface to write mbm_total_bytes_config") which added this function. The reported warning is: $ make C=1 CHECK=scripts/coccicheck arch/x86/kernel/cpu/resctrl/rdtgroup.o ... arch/x86/kernel/cpu/resctrl/rdtgroup.c:1621:5-8: Unneeded variable: "ret". Return "0" on line 1655 Remove the local variable 'ret'. [ bp: Massage commit message, make mbm_config_write_domain() void. ] Fixes: 92bd5a139033 ("x86/resctrl: Add interface to write mbm_total_bytes_config") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202401241810.jbd8Ipa1-lkp@intel.com/ Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/r/202401241810.jbd8Ipa1-lkp@intel.com
2024-01-24x86/resctrl: Implement new mba_MBps throttling heuristicTony Luck
The mba_MBps feedback loop increases throttling when a group is using more bandwidth than the target set by the user in the schemata file, and decreases throttling when below target. To avoid possibly stepping throttling up and down on every poll a flag "delta_comp" is set whenever throttling is changed to indicate that the actual change in bandwidth should be recorded on the next poll in "delta_bw". Throttling is only reduced if the current bandwidth plus delta_bw is below the user target. This algorithm works well if the workload has steady bandwidth needs. But it can go badly wrong if the workload moves to a different phase just as the throttling level changed. E.g. if the workload becomes essentially idle right as throttling level is increased, the value calculated for delta_bw will be more or less the old bandwidth level. If the workload then resumes, Linux may never reduce throttling because current bandwidth plus delta_bw is above the target set by the user. Implement a simpler heuristic by assuming that in the worst case the currently measured bandwidth is being controlled by the current level of throttling. Compute how much it may increase if throttling is relaxed to the next higher level. If that is still below the user target, then it is ok to reduce the amount of throttling. Fixes: ba0f26d8529c ("x86/intel_rdt/mba_sc: Prepare for feedback loop") Reported-by: Xiaochen Shen <xiaochen.shen@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Xiaochen Shen <xiaochen.shen@intel.com> Link: https://lore.kernel.org/r/20240122180807.70518-1-tony.luck@intel.com
2024-01-23x86/resctrl: Read supported bandwidth sources from CPUIDBabu Moger
If the BMEC (Bandwidth Monitoring Event Configuration) feature is supported, the bandwidth events can be configured. The maximum supported bandwidth bitmask can be read from CPUID: CPUID_Fn80000020_ECX_x03 [Platform QoS Monitoring Bandwidth Event Configuration] Bits Description 31:7 Reserved 6:0 Identifies the bandwidth sources that can be tracked. While at it, move the mask checking to mon_config_write() before iterating over all the domains. Also, print the valid bitmask when the user tries to configure invalid event configuration value. The CPUID details are documented in the Processor Programming Reference (PPR) Vol 1.1 for AMD Family 19h Model 11h B1 - 55901 Rev 0.25 in the Link tag. Fixes: dc2a3e857981 ("x86/resctrl: Add interface to read mbm_total_bytes_config") Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 Link: https://lore.kernel.org/r/669896fa512c7451319fa5ca2fdb6f7e015b5635.1705359148.git.babu.moger@amd.com
2024-01-23x86/resctrl: Remove hard-coded memory bandwidth limitBabu Moger
The QOS Memory Bandwidth Enforcement Limit is reported by CPUID_Fn80000020_EAX_x01 and CPUID_Fn80000020_EAX_x02: Bits Description 31:0 BW_LEN: Size of the QOS Memory Bandwidth Enforcement Limit. Newer processors can support higher bandwidth limit than the current hard-coded value. Remove latter and detect using CPUID instead. Also, update the register variables eax and edx to match the AMD CPUID definition. The CPUID details are documented in the Processor Programming Reference (PPR) Vol 1.1 for AMD Family 19h Model 11h B1 - 55901 Rev 0.25 in the Link tag below. Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature") Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 Link: https://lore.kernel.org/r/c26a8ca79d399ed076cf8bf2e9fbc58048808289.1705359148.git.babu.moger@amd.com
2024-01-22x86/resctrl: Fix unused variable warning in cache_alloc_hsw_probe()Tony Luck
In a "W=1" build gcc throws a warning: arch/x86/kernel/cpu/resctrl/core.c: In function ‘cache_alloc_hsw_probe’: arch/x86/kernel/cpu/resctrl/core.c:139:16: warning: variable ‘h’ set but not used Switch from wrmsr_safe() to wrmsrl_safe(), and from rdmsr() to rdmsrl() using a single u64 argument for the MSR value instead of the pair of u32 for the high and low halves. Signed-off-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Babu Moger <babu.moger@amd.com> Acked-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/r/ZULCd/TGJL9Dmncf@agluck-desk3
2024-01-21Linux 6.8-rc1v6.8-rc1Linus Torvalds
2024-01-21Merge tag 'bcachefs-2024-01-21' of https://evilpiepirate.org/git/bcachefsLinus Torvalds
Pull more bcachefs updates from Kent Overstreet: "Some fixes, Some refactoring, some minor features: - Assorted prep work for disk space accounting rewrite - BTREE_TRIGGER_ATOMIC: after combining our trigger callbacks, this makes our trigger context more explicit - A few fixes to avoid excessive transaction restarts on multithreaded workloads: fstests (in addition to ktest tests) are now checking slowpath counters, and that's shaking out a few bugs - Assorted tracepoint improvements - Starting to break up bcachefs_format.h and move on disk types so they're with the code they belong to; this will make room to start documenting the on disk format better. - A few minor fixes" * tag 'bcachefs-2024-01-21' of https://evilpiepirate.org/git/bcachefs: (46 commits) bcachefs: Improve inode_to_text() bcachefs: logged_ops_format.h bcachefs: reflink_format.h bcachefs; extents_format.h bcachefs: ec_format.h bcachefs: subvolume_format.h bcachefs: snapshot_format.h bcachefs: alloc_background_format.h bcachefs: xattr_format.h bcachefs: dirent_format.h bcachefs: inode_format.h bcachefs; quota_format.h bcachefs: sb-counters_format.h bcachefs: counters.c -> sb-counters.c bcachefs: comment bch_subvolume bcachefs: bch_snapshot::btime bcachefs: add missing __GFP_NOWARN bcachefs: opts->compression can now also be applied in the background bcachefs: Prep work for variable size btree node buffers bcachefs: grab s_umount only if snapshotting ...
2024-01-21Merge tag 'timers-core-2024-01-21' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Updates for time and clocksources: - A fix for the idle and iowait time accounting vs CPU hotplug. The time is reset on CPU hotplug which makes the accumulated systemwide time jump backwards. - Assorted fixes and improvements for clocksource/event drivers" * tag 'timers-core-2024-01-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick-sched: Fix idle and iowait sleeptime accounting vs CPU hotplug clocksource/drivers/ep93xx: Fix error handling during probe clocksource/drivers/cadence-ttc: Fix some kernel-doc warnings clocksource/drivers/timer-ti-dm: Fix make W=n kerneldoc warnings clocksource/timer-riscv: Add riscv_clock_shutdown callback dt-bindings: timer: Add StarFive JH8100 clint dt-bindings: timer: thead,c900-aclint-mtimer: separate mtime and mtimecmp regs
2024-01-21Merge tag 'powerpc-6.8-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Aneesh Kumar: - Increase default stack size to 32KB for Book3S Thanks to Michael Ellerman. * tag 'powerpc-6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: Increase default stack size to 32KB
2024-01-21bcachefs: Improve inode_to_text()Kent Overstreet
Add line breaks - inode_to_text() is now much easier to read. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: logged_ops_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: reflink_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs; extents_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: ec_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: subvolume_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: snapshot_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: alloc_background_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: xattr_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: dirent_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: inode_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs; quota_format.hKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: sb-counters_format.hKent Overstreet
bcachefs_format.h has gotten too big; let's do some organizing. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: counters.c -> sb-counters.cKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: comment bch_subvolumeKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: bch_snapshot::btimeKent Overstreet
Add a field to bch_snapshot for creation time; this will be important when we start exposing the snapshot tree to userspace. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: add missing __GFP_NOWARNKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: opts->compression can now also be applied in the backgroundKent Overstreet
The "apply this compression method in the background" paths now use the compression option if background_compression is not set; this means that setting or changing the compression option will cause existing data to be compressed accordingly in the background. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Prep work for variable size btree node buffersKent Overstreet
bcachefs btree nodes are big - typically 256k - and btree roots are pinned in memory. As we're now up to 18 btrees, we now have significant memory overhead in mostly empty btree roots. And in the future we're going to start enforcing that certain btree node boundaries exist, to solve lock contention issues - analagous to XFS's AGIs. Thus, we need to start allocating smaller btree node buffers when we can. This patch changes code that refers to the filesystem constant c->opts.btree_node_size to refer to the btree node buffer size - btree_buf_bytes() - where appropriate. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: grab s_umount only if snapshottingSu Yue
When I was testing mongodb over bcachefs with compression, there is a lockdep warning when snapshotting mongodb data volume. $ cat test.sh prog=bcachefs $prog subvolume create /mnt/data $prog subvolume create /mnt/data/snapshots while true;do $prog subvolume snapshot /mnt/data /mnt/data/snapshots/$(date +%s) sleep 1s done $ cat /etc/mongodb.conf systemLog: destination: file logAppend: true path: /mnt/data/mongod.log storage: dbPath: /mnt/data/ lockdep reports: [ 3437.452330] ====================================================== [ 3437.452750] WARNING: possible circular locking dependency detected [ 3437.453168] 6.7.0-rc7-custom+ #85 Tainted: G E [ 3437.453562] ------------------------------------------------------ [ 3437.453981] bcachefs/35533 is trying to acquire lock: [ 3437.454325] ffffa0a02b2b1418 (sb_writers#10){.+.+}-{0:0}, at: filename_create+0x62/0x190 [ 3437.454875] but task is already holding lock: [ 3437.455268] ffffa0a02b2b10e0 (&type->s_umount_key#48){.+.+}-{3:3}, at: bch2_fs_file_ioctl+0x232/0xc90 [bcachefs] [ 3437.456009] which lock already depends on the new lock. [ 3437.456553] the existing dependency chain (in reverse order) is: [ 3437.457054] -> #3 (&type->s_umount_key#48){.+.+}-{3:3}: [ 3437.457507] down_read+0x3e/0x170 [ 3437.457772] bch2_fs_file_ioctl+0x232/0xc90 [bcachefs] [ 3437.458206] __x64_sys_ioctl+0x93/0xd0 [ 3437.458498] do_syscall_64+0x42/0xf0 [ 3437.458779] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 3437.459155] -> #2 (&c->snapshot_create_lock){++++}-{3:3}: [ 3437.459615] down_read+0x3e/0x170 [ 3437.459878] bch2_truncate+0x82/0x110 [bcachefs] [ 3437.460276] bchfs_truncate+0x254/0x3c0 [bcachefs] [ 3437.460686] notify_change+0x1f1/0x4a0 [ 3437.461283] do_truncate+0x7f/0xd0 [ 3437.461555] path_openat+0xa57/0xce0 [ 3437.461836] do_filp_open+0xb4/0x160 [ 3437.462116] do_sys_openat2+0x91/0xc0 [ 3437.462402] __x64_sys_openat+0x53/0xa0 [ 3437.462701] do_syscall_64+0x42/0xf0 [ 3437.462982] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 3437.463359] -> #1 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}: [ 3437.463843] down_write+0x3b/0xc0 [ 3437.464223] bch2_write_iter+0x5b/0xcc0 [bcachefs] [ 3437.464493] vfs_write+0x21b/0x4c0 [ 3437.464653] ksys_write+0x69/0xf0 [ 3437.464839] do_syscall_64+0x42/0xf0 [ 3437.465009] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 3437.465231] -> #0 (sb_writers#10){.+.+}-{0:0}: [ 3437.465471] __lock_acquire+0x1455/0x21b0 [ 3437.465656] lock_acquire+0xc6/0x2b0 [ 3437.465822] mnt_want_write+0x46/0x1a0 [ 3437.465996] filename_create+0x62/0x190 [ 3437.466175] user_path_create+0x2d/0x50 [ 3437.466352] bch2_fs_file_ioctl+0x2ec/0xc90 [bcachefs] [ 3437.466617] __x64_sys_ioctl+0x93/0xd0 [ 3437.466791] do_syscall_64+0x42/0xf0 [ 3437.466957] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 3437.467180] other info that might help us debug this: [ 3437.469670] 2 locks held by bcachefs/35533: other info that might help us debug this: [ 3437.467507] Chain exists of: sb_writers#10 --> &c->snapshot_create_lock --> &type->s_umount_key#48 [ 3437.467979] Possible unsafe locking scenario: [ 3437.468223] CPU0 CPU1 [ 3437.468405] ---- ---- [ 3437.468585] rlock(&type->s_umount_key#48); [ 3437.468758] lock(&c->snapshot_create_lock); [ 3437.469030] lock(&type->s_umount_key#48); [ 3437.469291] rlock(sb_writers#10); [ 3437.469434] *** DEADLOCK *** [ 3437.469670] 2 locks held by bcachefs/35533: [ 3437.469838] #0: ffffa0a02ce00a88 (&c->snapshot_create_lock){++++}-{3:3}, at: bch2_fs_file_ioctl+0x1e3/0xc90 [bcachefs] [ 3437.470294] #1: ffffa0a02b2b10e0 (&type->s_umount_key#48){.+.+}-{3:3}, at: bch2_fs_file_ioctl+0x232/0xc90 [bcachefs] [ 3437.470744] stack backtrace: [ 3437.470922] CPU: 7 PID: 35533 Comm: bcachefs Kdump: loaded Tainted: G E 6.7.0-rc7-custom+ #85 [ 3437.471313] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 [ 3437.471694] Call Trace: [ 3437.471795] <TASK> [ 3437.471884] dump_stack_lvl+0x57/0x90 [ 3437.472035] check_noncircular+0x132/0x150 [ 3437.472202] __lock_acquire+0x1455/0x21b0 [ 3437.472369] lock_acquire+0xc6/0x2b0 [ 3437.472518] ? filename_create+0x62/0x190 [ 3437.472683] ? lock_is_held_type+0x97/0x110 [ 3437.472856] mnt_want_write+0x46/0x1a0 [ 3437.473025] ? filename_create+0x62/0x190 [ 3437.473204] filename_create+0x62/0x190 [ 3437.473380] user_path_create+0x2d/0x50 [ 3437.473555] bch2_fs_file_ioctl+0x2ec/0xc90 [bcachefs] [ 3437.473819] ? lock_acquire+0xc6/0x2b0 [ 3437.474002] ? __fget_files+0x2a/0x190 [ 3437.474195] ? __fget_files+0xbc/0x190 [ 3437.474380] ? lock_release+0xc5/0x270 [ 3437.474567] ? __x64_sys_ioctl+0x93/0xd0 [ 3437.474764] ? __pfx_bch2_fs_file_ioctl+0x10/0x10 [bcachefs] [ 3437.475090] __x64_sys_ioctl+0x93/0xd0 [ 3437.475277] do_syscall_64+0x42/0xf0 [ 3437.475454] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 3437.475691] RIP: 0033:0x7f2743c313af ====================================================== In __bch2_ioctl_subvolume_create(), we grab s_umount unconditionally and unlock it at the end of the function. There is a comment "why do we need this lock?" about the lock coming from commit 42d237320e98 ("bcachefs: Snapshot creation, deletion") The reason is that __bch2_ioctl_subvolume_create() calls sync_inodes_sb() which enforce locked s_umount to writeback all dirty nodes before doing snapshot works. Fix it by read locking s_umount for snapshotting only and unlocking s_umount after sync_inodes_sb(). Signed-off-by: Su Yue <glass.su@suse.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: kvfree bch_fs::snapshots in bch2_fs_snapshots_exitSu Yue
bch_fs::snapshots is allocated by kvzalloc in __snapshot_t_mut. It should be freed by kvfree not kfree. Or umount will triger: [ 406.829178 ] BUG: unable to handle page fault for address: ffffe7b487148008 [ 406.830676 ] #PF: supervisor read access in kernel mode [ 406.831643 ] #PF: error_code(0x0000) - not-present page [ 406.832487 ] PGD 0 P4D 0 [ 406.832898 ] Oops: 0000 [#1] PREEMPT SMP PTI [ 406.833512 ] CPU: 2 PID: 1754 Comm: umount Kdump: loaded Tainted: G OE 6.7.0-rc7-custom+ #90 [ 406.834746 ] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 [ 406.835796 ] RIP: 0010:kfree+0x62/0x140 [ 406.836197 ] Code: 80 48 01 d8 0f 82 e9 00 00 00 48 c7 c2 00 00 00 80 48 2b 15 78 9f 1f 01 48 01 d0 48 c1 e8 0c 48 c1 e0 06 48 03 05 56 9f 1f 01 <48> 8b 50 08 48 89 c7 f6 c2 01 0f 85 b0 00 00 00 66 90 48 8b 07 f6 [ 406.837810 ] RSP: 0018:ffffb9d641607e48 EFLAGS: 00010286 [ 406.838213 ] RAX: ffffe7b487148000 RBX: ffffb9d645200000 RCX: ffffb9d641607dc4 [ 406.838738 ] RDX: 000065bb00000000 RSI: ffffffffc0d88b84 RDI: ffffb9d645200000 [ 406.839217 ] RBP: ffff9a4625d00068 R08: 0000000000000001 R09: 0000000000000001 [ 406.839650 ] R10: 0000000000000001 R11: 000000000000001f R12: ffff9a4625d4da80 [ 406.840055 ] R13: ffff9a4625d00000 R14: ffffffffc0e2eb20 R15: 0000000000000000 [ 406.840451 ] FS: 00007f0a264ffb80(0000) GS:ffff9a4e2d500000(0000) knlGS:0000000000000000 [ 406.840851 ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 406.841125 ] CR2: ffffe7b487148008 CR3: 000000018c4d2000 CR4: 00000000000006f0 [ 406.841464 ] Call Trace: [ 406.841583 ] <TASK> [ 406.841682 ] ? __die+0x1f/0x70 [ 406.841828 ] ? page_fault_oops+0x159/0x470 [ 406.842014 ] ? fixup_exception+0x22/0x310 [ 406.842198 ] ? exc_page_fault+0x1ed/0x200 [ 406.842382 ] ? asm_exc_page_fault+0x22/0x30 [ 406.842574 ] ? bch2_fs_release+0x54/0x280 [bcachefs] [ 406.842842 ] ? kfree+0x62/0x140 [ 406.842988 ] ? kfree+0x104/0x140 [ 406.843138 ] bch2_fs_release+0x54/0x280 [bcachefs] [ 406.843390 ] kobject_put+0xb7/0x170 [ 406.843552 ] deactivate_locked_super+0x2f/0xa0 [ 406.843756 ] cleanup_mnt+0xba/0x150 [ 406.843917 ] task_work_run+0x59/0xa0 [ 406.844083 ] exit_to_user_mode_prepare+0x197/0x1a0 [ 406.844302 ] syscall_exit_to_user_mode+0x16/0x40 [ 406.844510 ] do_syscall_64+0x4e/0xf0 [ 406.844675 ] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 406.844907 ] RIP: 0033:0x7f0a2664e4fb Signed-off-by: Su Yue <glass.su@suse.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: bios must be 512 byte alginedKent Overstreet
Fixes: 023f9ac9f70f bcachefs: Delete dio read alignment check Reported-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: remove redundant variable tmpColin Ian King
The variable tmp is being assigned a value but it isn't being read afterwards. The assignment is redundant and so tmp can be removed. Cleans up clang scan build warning: warning: Although the value stored to 'ret' is used in the enclosing expression, the value is never actually read from 'ret' [deadcode.DeadStores] Signed-off-by: Colin Ian King <colin.i.king@gmail.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Improve trace_trans_restart_relockKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Fix excess transaction restarts in __bchfs_fallocate()Kent Overstreet
drop_locks_do() should not be used in a fastpath without first trying the do in nonblocking mode - the unlock and relock will cause excessive transaction restarts and potentially livelocking with other threads that are contending for the same locks. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: extents_to_bp_stateKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: bkey_and_val_eq()Kent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Better journal tracepointsKent Overstreet
Factor out bch2_journal_bufs_to_text(), and use it in the journal_entry_full() tracepoint; when we can't get a journal reservation we need to know the outstanding journal entry sizes to know if the problem is due to excessive flushing. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Print size of superblock with space allocatedKent Overstreet
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Avoid flushing the journal in the discard pathKent Overstreet
When issuing discards, we may need to flush the journal if there's too many buckets that can't be discarded until a journal flush. But the heuristic was bad; we should be comparing the number of buckets that need to flushes against the number of free buckets, not the number of buckets we saw. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Improve move_extent tracepointKent Overstreet
Also print out the data_opts, so that we can see what specifically is being done to an extent. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Add missing bch2_moving_ctxt_flush_all()Kent Overstreet
This fixes a bug with rebalance IOs getting stuck with reads completed, but writes never being issued. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: Re-add move_extent_write tracepointKent Overstreet
It appears this was accidentally deleted at some point - also, do a bit of cleanup. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2024-01-21bcachefs: bch2_kthread_io_clock_wait() no longer sleeps until full amountKent Overstreet
Drop t he loop in bch2_kthread_io_clock_wait(): this allows the code that uses it to be woken up for other reasons, and fixes a bug where rebalance wouldn't wake up when a scan was requested. This raises the possibility of spurious wakeups, but callers should always be able to handle that reasonably well. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
generated by cgit v1.2.3 (git 2.39.1) at 2025-07-29 21:23:34 +0000