Re: Re: [PATCH bpf v2] bpf: Fix deadlock when freeing cgroup storage

From: Abel Wu
Date: Wed Jan 29 2025 - 01:24:00 EST


On 1/28/25 7:05 AM, Martin KaFai Lau Wrote:
On 1/27/25 2:15 PM, Alexei Starovoitov wrote:
On Sun, Jan 26, 2025 at 1:31 AM Abel Wu <wuyun.abel@xxxxxxxxxxxxx> wrote:

On 1/25/25 4:20 AM, Martin KaFai Lau Wrote:

imo, that should be a better option instead of having more unnecessary failures in all other normal use cases which will not be interested in tracing cgroup_storage_ptr().

Martin,

task_storage_map_free() is doing this busy inc/dec already,
in that sense doing the same in cgroup_storage_map_free() fits.

sgtm. Agree to be consistent with the task_storage_map_free.

would be nice if the busy inc/dec usage can be revisited after the rqspinlock work.

Agree, and 1ms interval of deadlock dection seems acceptable
for most workloads.


Acked-by: Martin KaFai Lau <martin.lau@xxxxxxxxxx>

Thanks Alexei, Martin.