Re: [PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Christophe Leroy
Le 25/11/2022 à 06:38, Naveen N. Rao a écrit : > Christophe Leroy wrote: >> >> >> Le 24/11/2022 à 14:49, Naveen N. Rao a écrit : >>> Christophe Leroy wrote: Le 24/11/2022 à 11:13, Naveen N. Rao a écrit : > Christophe Leroy wrote: In what direction could that change in

Re: [PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Naveen N. Rao
Christophe Leroy wrote: Le 24/11/2022 à 14:49, Naveen N. Rao a écrit : Christophe Leroy wrote: Le 24/11/2022 à 11:13, Naveen N. Rao a écrit : Christophe Leroy wrote: In what direction could that change in the future ? For me if they change that it becomes an API change. More of an ext

Re: [PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Christophe Leroy
Le 24/11/2022 à 14:49, Naveen N. Rao a écrit : > Christophe Leroy wrote: >> >> >> Le 24/11/2022 à 11:13, Naveen N. Rao a écrit : >>> Christophe Leroy wrote: ldimm64 is not only used for loading function addresses, and >>> >>> That's probably true today, but I worry that that can change upstr

Re: [PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Naveen N. Rao
Christophe Leroy wrote: Le 24/11/2022 à 11:13, Naveen N. Rao a écrit : Christophe Leroy wrote: ldimm64 is not only used for loading function addresses, and That's probably true today, but I worry that that can change upstream and we may not notice at all. Not sure what you mean. Today P

Re: [PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Christophe Leroy
Le 24/11/2022 à 11:13, Naveen N. Rao a écrit : > Christophe Leroy wrote: >> ldimm64 is not only used for loading function addresses, and > > That's probably true today, but I worry that that can change upstream > and we may not notice at all. Not sure what you mean. Today POWERPC considers th

Re: [PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Naveen N. Rao
Christophe Leroy wrote: ldimm64 is not only used for loading function addresses, and That's probably true today, but I worry that that can change upstream and we may not notice at all. the NOPs added for padding are impacting performance, so avoid them when not necessary. On QEMU mac99, wi

[PATCH] powerpc/bpf: Only update ldimm64 during extra pass when it is an address

2022-11-24 Thread Christophe Leroy
ldimm64 is not only used for loading function addresses, and the NOPs added for padding are impacting performance, so avoid them when not necessary. On QEMU mac99, with the patch: test_bpf: #829 ALU64_MOV_K: all immediate value magnitudes jited:1 167436810 PASS test_bpf: #831 ALU64_OR_K: all imm