Re: [RFC/PATCHSET 0/9] perf record: Implement BPF sample filter (v4)

From: Ravi Bangoria
Date: Fri Mar 10 2023 - 04:58:29 EST


> It requires samples satisfy all the filter expressions otherwise it'd
> drop the sample. IOW filter expressions are connected with logical AND
> operations unless they used "||" explicitly. So if user has something
> like 'A, B || C, D', then BOTH A and D should be true AND either B or C
> also needs to be true.
>
> Essentially the BPF filter expression is:
>
> <term> <operator> <value> (("," | "||") <term> <operator> <value>)*
>
> The <term> can be one of:
> ip, id, tid, pid, cpu, time, addr, period, txn, weight, phys_addr,
> code_pgsz, data_pgsz, weight1, weight2, weight3, ins_lat, retire_lat,
> p_stage_cyc, mem_op, mem_lvl, mem_snoop, mem_remote, mem_lock,
> mem_dtlb, mem_blk, mem_hops
>
> The <operator> can be one of:
> ==, !=, >, >=, <, <=, &
>
> The <value> can be one of:
> <number> (for any term)
> na, load, store, pfetch, exec (for mem_op)
> l1, l2, l3, l4, cxl, io, any_cache, lfb, ram, pmem (for mem_lvl)
> na, none, hit, miss, hitm, fwd, peer (for mem_snoop)
> remote (for mem_remote)
> na, locked (for mem_locked)
> na, l1_hit, l1_miss, l2_hit, l2_miss, any_hit, any_miss, walk, fault (for mem_dtlb)
> na, by_data, by_addr (for mem_blk)
> hops0, hops1, hops2, hops3 (for mem_hops)

I think this and few examples should be added in perf-record man page.

Thanks,
Ravi