Skip to content

LoongArch: BPF: Optimize the calculation method of jmp_offset in the emit_bpf_tail_call function #9013

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom
Open
wants to merge 1 commit into
base: bpf-next_base
Choose a base branch
from
Open

LoongArch: BPF: Optimize the calculation method of jmp_offset in the emit_bpf_tail_call function #9013

wants to merge 1 commit into from
+9 −19

Conversation

kernel-patches-daemon-bpf[bot]
Copy link

Pull request for series with
subject: LoongArch: BPF: Optimize the calculation method of jmp_offset in the emit_bpf_tail_call function
version: 1
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970

@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: c5cebb2
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 90b83ef
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 977c360 to 2845b18 Compare May 29, 2025 05:19
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 90b83ef
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 2845b18 to 9a79fd9 Compare May 30, 2025 14:52
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: bb1556e
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 9a79fd9 to 6f947b4 Compare June 1, 2025 18:04
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: bb1556e
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 6f947b4 to c2df764 Compare June 2, 2025 06:41
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: cd2e103
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from c2df764 to 7cd9399 Compare June 2, 2025 17:54
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: cd2e103
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 14b9b71 to e6f4f75 Compare June 5, 2025 20:28
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: a570f38
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from e6f4f75 to 66d135f Compare June 5, 2025 20:53
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 64a064c
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 66d135f to a0e9418 Compare June 5, 2025 21:03
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: e41079f
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from a0e9418 to ce9c6e2 Compare June 7, 2025 02:28
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: e41079f
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from ce9c6e2 to 264ec8f Compare June 9, 2025 20:00
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 97ebac5
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 264ec8f to 1b3d385 Compare June 9, 2025 23:46
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 2bc0575
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf kernel-patches-daemon-bpf bot force-pushed the series/966970=>bpf-next branch from 1b3d385 to 7b21122 Compare June 9, 2025 23:53
@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 5fcf896
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

@kernel-patches-daemon-bpf
Copy link
Author

Upstream branch: 2d72dd1
series: https://patchwork.kernel.org/project/netdevbpf/list/?series=966970
version: 1

LoongArch: BPF: Optimize the calculation method of jmp_offset in the …
19e79e5 
…emit_bpf_tail_call function

For a ebpf subprog JIT，the last call bpf_int_jit_compile function will
directly enter the skip_init_ctx process. At this point, out_offset = -1,
the jmp_offset in emit_bpf_tail_call is calculated
by #define jmp_offset (out_offset - (cur_offset)) is a negative number,
which does not meet expectations.The final generated assembly as follow.

54:	bgeu        	$a2, $t1, -8	    # 0x0000004c
58:	addi.d      	$a6, $s5, -1
5c:	bltz        	$a6, -16	    # 0x0000004c
60:	alsl.d      	$t2, $a2, $a1, 0x3
64:	ld.d        	$t2, $t2, 264
68:	beq         	$t2, $zero, -28	    # 0x0000004c

Before apply this patch, the follow test case will reveal soft lock issues.

cd tools/testing/selftests/bpf/
./test_progs --allow=tailcalls/tailcall_bpf2bpf_1

dmesg:
watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [test_progs:25056]

Signed-off-by: Haoran Jiang <[email protected]>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Reviewers
No reviews
Assignees
No one assigned
Labels
bpf-next new V1-ci-pass V1
Projects
None yet
Milestone
No milestone
Development

Successfully merging this pull request may close these issues.
0 participants