linux/kernel/bpf
David Vernet 90660309b0 bpf: Add kfuncs for storing struct task_struct * as a kptr
Now that BPF supports adding new kernel functions with kfuncs, and
storing kernel objects in maps with kptrs, we can add a set of kfuncs
which allow struct task_struct objects to be stored in maps as
referenced kptrs. The possible use cases for doing this are plentiful.
During tracing, for example, it would be useful to be able to collect
some tasks that performed a certain operation, and then periodically
summarize who they are, which cgroup they're in, how much CPU time
they've utilized, etc.

In order to enable this, this patch adds three new kfuncs:

struct task_struct *bpf_task_acquire(struct task_struct *p);
struct task_struct *bpf_task_kptr_get(struct task_struct **pp);
void bpf_task_release(struct task_struct *p);

A follow-on patch will add selftests validating these kfuncs.

Signed-off-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/r/20221120051004.3605026-4-void@manifault.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-11-20 09:16:21 -08:00
..
preload bpf: iterators: Build and use lightweight bootstrap version of bpftool 2022-07-15 12:01:30 -07:00
Kconfig rcu: Make the TASKS_RCU Kconfig option be selected 2022-04-20 16:52:58 -07:00
Makefile bpf: Implement cgroup storage available to non-cgroup-attached bpf progs 2022-10-25 23:19:19 -07:00
arraymap.c bpf: Do btf_record_free outside map_free callback 2022-11-17 19:11:31 -08:00
bloom_filter.c treewide: use get_random_u32() when possible 2022-10-11 17:42:58 -06:00
bpf_cgrp_storage.c bpf: Implement cgroup storage available to non-cgroup-attached bpf progs 2022-10-25 23:19:19 -07:00
bpf_inode_storage.c bpf: Refactor some inode/task/sk storage functions for reuse 2022-10-25 23:19:19 -07:00
bpf_iter.c bpf: Initialize the bpf_run_ctx in bpf_iter_run_prog() 2022-08-18 17:06:13 -07:00
bpf_local_storage.c bpf: Consolidate spin_lock, timer management into btf_record 2022-11-03 22:19:40 -07:00
bpf_lru_list.c
bpf_lru_list.h printk: stop including cache.h from printk.h 2022-05-13 07:20:07 -07:00
bpf_lsm.c Networking changes for 6.1. 2022-10-04 13:38:03 -07:00
bpf_struct_ops.c bpf: Remove is_valid_bpf_tramp_flags() 2022-07-11 21:04:58 +02:00
bpf_struct_ops_types.h bpf: Add dummy BPF STRUCT_OPS for test purpose 2021-11-01 14:10:00 -07:00
bpf_task_storage.c bpf: Refactor some inode/task/sk storage functions for reuse 2022-10-25 23:19:19 -07:00
btf.c bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs 2022-11-20 09:16:21 -08:00
cgroup.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-10-03 17:44:18 -07:00
cgroup_iter.c bpf-next-for-netdev 2022-11-02 08:18:27 -07:00
core.c bpf: Introduce bpf_obj_new 2022-11-17 19:22:14 -08:00
cpumap.c bpf: Expand map key argument of bpf_redirect_map to u64 2022-11-15 09:00:27 -08:00
devmap.c bpf: Expand map key argument of bpf_redirect_map to u64 2022-11-15 09:00:27 -08:00
disasm.c
disasm.h
dispatcher.c bpf: Fix dispatcher patchable function entry to 5 bytes nop 2022-10-20 18:57:51 -07:00
hashtab.c bpf: Do btf_record_free outside map_free callback 2022-11-17 19:11:31 -08:00
helpers.c bpf: Add kfuncs for storing struct task_struct * as a kptr 2022-11-20 09:16:21 -08:00
inode.c bpf: Convert bpf_preload.ko to use light skeleton. 2022-02-10 23:31:51 +01:00
link_iter.c bpf: Add bpf_link iterator 2022-05-10 11:20:45 -07:00
local_storage.c bpf: Consolidate spin_lock, timer management into btf_record 2022-11-03 22:19:40 -07:00
lpm_trie.c bpf: Use bpf_map_area_alloc consistently on bpf map creation 2022-08-10 11:50:43 -07:00
map_in_map.c bpf: Add comments for map BTF matching requirement for bpf_list_head 2022-11-17 19:22:14 -08:00
map_in_map.h
map_iter.c bpf: Introduce MEM_RDONLY flag 2021-12-18 13:27:41 -08:00
memalloc.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-10-24 13:44:11 -07:00
mmap_unlock_work.h bpf: Introduce helper bpf_find_vma 2021-11-07 11:54:51 -08:00
net_namespace.c net: Add includes masked by netdevice.h including uapi/bpf.h 2021-12-29 20:03:05 -08:00
offload.c bpf: Use bpf_map_area_alloc consistently on bpf map creation 2022-08-10 11:50:43 -07:00
percpu_freelist.c bpf: Simplify code by using for_each_cpu_wrap() 2022-09-10 16:18:55 -07:00
percpu_freelist.h
prog_iter.c
queue_stack_maps.c bpf: Remove unneeded memset in queue_stack_map creation 2022-08-10 11:48:22 -07:00
reuseport_array.c net: Fix suspicious RCU usage in bpf_sk_reuseport_detach() 2022-08-17 16:42:59 -07:00
ringbuf.c bpf: Rename MEM_ALLOC to MEM_RINGBUF 2022-11-14 21:52:45 -08:00
stackmap.c perf/bpf: Always use perf callchains if exist 2022-09-13 15:03:22 +02:00
syscall.c bpf: Add comments for map BTF matching requirement for bpf_list_head 2022-11-17 19:22:14 -08:00
sysfs_btf.c
task_iter.c - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
tnum.c
trampoline.c bpf: Remove prog->active check for bpf_lsm and bpf_iter 2022-10-25 23:11:46 -07:00
verifier.c bpf: Allow trusted pointers to be passed to KF_TRUSTED_ARGS kfuncs 2022-11-20 09:16:21 -08:00