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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Stat-Signature: x175y19di4xnf5gjgeywztybgh6dnefu X-Rspamd-Queue-Id: CFBAE180008 X-Rspamd-Server: rspam07 X-HE-Tag: 1741203845-689229 X-HE-Meta: U2FsdGVkX19TymmtP/B4yqGXw0uEryHlMOgkAM0zlwMi/MUpZxeI/YMasu3YTWyM0wh1UHb96Bp435ASURGRMHcZz+BFtKxij/zYDJjYPL9CqTW9M5kOSJ1KEKKBk7tlgqmftw2RK1kT/hyU7NCI/9en1H3JCilIrjS9iqI8tQFFWlpmB8Xm1X24dpqO+uzvOW5JOpKV/uUMEQEDcTQSPGRvfy65TIT/lhdSkSfpmumLlC8bpC87/xucjWAgS2J7XTLrLWdK8quKR+llqm9tZHJlabliBqL1yezeRee4+XEn+SH/oo16ZZ8xowS2fA/Ceq2KpccPuw8nCMgu04NsZ3uFpc6+SF5yB+dFJw0aVLiJqzxnzP1DLD6DAQ/IIpmPajNPwIG0f9daRUgh0N6SG+DgExS3mXn50YI28kATksSaZxfm1Ju99uSDGIVfpHpjXIYcFlIdR1PT2AeP49C9dKffICOP6PaaIyjtB4qAg2HuO3Xn3+5yY8dUbeIL2qzK8wSD7rYmfFEGTQZTUbMUejfCUrk3fE3ZvKKkt275HV43eny6w1SMh+uAEwOKbfKS8GsZIX1GH2ezj1SGD6vcQ58P9lpzBa+ZUQ6n8t/i8hUiQm3QYx67Wz+4dkg0R/YpND02wKF0+2qyEEED29BHJCYXg1TK6eddEi4ot6ABBShZDR1pGxDOE9906+F231opBivV/hyZYYW+4Qh5YD46igsJR1kdDAi6PuLiPnletVlZSUm1zt41T8sAxrZrsu5cOo/tzgQyAKVeksFn2tduUSprT9K/ZOMQPNh963+5r4Inv2Nm3pqrkGr9MUXZO6C0kx1b/rFIxwVKaLNf1WIFLruQUeDGzArDacSS/a6F0ZqZYDirT0RrgzLZHrjDyAtHjL0fkbgf9jGKnvpdNndS2/KOViRbgBdvcaiUi9TvNm4Y3KGPNxVOhm9Cky6FwzHMb9/ZiNuJlh/zc6chMw+ HDo4Cqzj 9dllIoPlkQv7CL34L4V8M5lDZxKrtQX/xDjt65DyAQXjn1dKauY97GhmbpeyI2DMcCL8VAKhtXujINsRa2kECF0xYdisuAVhj8uN0QDwL4Ul7ti1qRh8pWOrdOgiWhzcKlRacMh/0uc6TWnaCCZpzqdLYkdfFvGheFg7cWqRe/OeL+8YP+ijuOiAgamvnGpWzz2z3rf8vQU7fJqYWMkwk5CKSb2x6HwPNY/EbYaHJYgjfTtvCN1OPpP5HtBzy90DwaVk8KAdrx5g5J+4MeR2kcXLqxJmPt0fH1yQ3kfAdSm9rnFHtAnacv7ygr8sbRFu+4A15baxoMlEMs3rbIEcyEHGZrFGmOTEI4dfjw7CaqNu1E3bfn+UgeCjrZ6b5wr9SYDTZAkpy9IjtPNJr3vrBSn7+BbWDz9G6d5hgW2EiygjATPTveT1FOFTAX9EDmEKiDKcXi1LfxZkny1w= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Mar 5, 2025 at 7:22=E2=80=AFAM Oleg Nesterov wrot= e: > > On 03/04, David Hildenbrand wrote: > > > > Currently, uprobe_write_opcode() implements COW-breaking manually, whic= h is > > really far from ideal. > > To say at least ;) > > David, thanks for doing this. I'll try to read 3/3 tomorrow, but I don't > think I can really help. Let me repeat, this code was written many years > ago, I forgot everything, and today my understanding of mm/ is very poor. > But I'll try anyway. > > > Are there any uprobe tests / benchmarks that are worth running? > > All I know about uprobe tests is that bpf people run a lot of tests which > use uprobes. > > Andrii, Jiri, what you advise? > We do have a bunch of tests within BPF selftests: cd tools/testing/selftest/bpf && make -j$(nproc) && sudo ./test_progs -t up= robe I also built an uprobe-stress tool to validate uprobe optimizations I was doing, this one is the most stand-alone thing to use for testing, please consider checking that. You can find it at [0], and see also [1] and [2] where I was helping Peter to build it from sources, so that might be useful for you as well, if you run into problems with building. Running something like `sudo ./uprobe-stress -a10 -t5 -m5 -f3` would hammer on this quite a bit. I'm just about to leave on a short vacation, so won't have time to go over patches, but I plan to look at them when I'm back next week. [0] https://github.com/libbpf/libbpf-bootstrap/tree/uprobe-stress [1] https://lore.kernel.org/linux-trace-kernel/CAEf4BzZ+ygwfk8FKn5AS_Ny= =3DigvGcFzdDLE2FjcvwjCKazEWMA@mail.gmail.com/ [2] https://lore.kernel.org/linux-trace-kernel/CAEf4BzZqKCR-EQz6LTi-YvFY4= RnYb_NnQXtwgZCv6aUo7gjkHg@mail.gmail.com > Oleg. >