Re: [PATCH v3 0/7] perf cs_etm: Basic support for virtual/kernel timestamps

From: James Clark
Date: Wed Jan 11 2023 - 06:39:20 EST




On 10/01/2023 16:42, Tanmay Jagdale wrote:
> Hi James,
>
[...]

>> base-commit: 09e6f9f98370be9a9f8978139e0eb1be87d1125f
> I have tested this patch set on our platform and able to see updated
> timestamp values in perf script's output.
>
> $ perf record -e cs_etm/cycacc,@tmc_etr0/k -C 9 taskset -c 9 sleep 2
> $ perf script --itrace=i1ns --ns -Fcomm,tid,pid,time,cpu,event,ip,sym,addr,symoff,flags,callindent
>
> At certain points noticed that hardware emits same timestamp packets
> but with updated cycle count (CC) values. A small snippet of the log:
>
> Idx:100; ID:12; I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0xFFFF8000086A761C ~[0x761C]
> Idx:103; ID:12; I_TIMESTAMP : Timestamp.; Updated val = 0x2f373e37e02; CC=0x3d
> Idx:107; ID:12; I_ATOM_F2 : Atom format 2.; EN
> Idx:108; ID:12; I_TIMESTAMP : Timestamp.; Updated val = 0x2f373e37e02; CC=0x3f
> Idx:112; ID:12; I_ATOM_F1 : Atom format 1.; N
> Idx:113; ID:12; I_TIMESTAMP : Timestamp.; Updated val = 0x2f373e37e02; CC=0x45
> Idx:116; ID:12; I_ATOM_F1 : Atom format 1.; E
> Idx:117; ID:12; I_ADDR_S_IS0 : Address, Short, IS0.; Addr=0xFFFF8000086B52D4 ~[0x152D4]

Hi Tanmay,

Are you able to email or send a download link with the perf archive and
perf.data file of this recording please?

Thanks
James