Hello:
This patch was applied to bpf/bpf-next.git (master)
by Alexei Starovoitov <ast@xxxxxxxxxx>:
On Mon, 18 Apr 2022 21:32:30 -0700 you wrote:
> LLVM commit [1] changed loop pragma behavior such that
> full loop unroll is always honored with user pragma.
> Previously, unroll count also depends on the unrolled
> code size. For pyperf600, without [1], the loop unroll
> count is 150. With [1], the loop unroll count is 600.
>
> The unroll count of 600 caused the program size close to
> 298k and this caused the following code is generated:
> 0: 7b 1a 00 ff 00 00 00 00 *(u64 *)(r10 - 256) = r1
> ; uint64_t pid_tgid = bpf_get_current_pid_tgid();
> 1: 85 00 00 00 0e 00 00 00 call 14
> 2: bf 06 00 00 00 00 00 00 r6 = r0
> ; pid_t pid = (pid_t)(pid_tgid >> 32);
> 3: bf 61 00 00 00 00 00 00 r1 = r6
> 4: 77 01 00 00 20 00 00 00 r1 >>= 32
> 5: 63 1a fc ff 00 00 00 00 *(u32 *)(r10 - 4) = r1
> 6: bf a2 00 00 00 00 00 00 r2 = r10
> 7: 07 02 00 00 fc ff ff ff r2 += -4
> ; PidData* pidData = bpf_map_lookup_elem(&pidmap, &pid);
> 8: 18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
> 10: 85 00 00 00 01 00 00 00 call 1
> 11: bf 08 00 00 00 00 00 00 r8 = r0
> ; if (!pidData)
> 12: 15 08 15 e8 00 00 00 00 if r8 == 0 goto -6123 <LBB0_27588+0xffffffffffdae100>
>
> [...]
Here is the summary with links:
- [bpf-next] selftests/bpf: limit unroll_count for pyperf600 test
https://git.kernel.org/bpf/bpf-next/c/8c89b5db7a28
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
