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charset=US-ASCII X-Rspamd-Queue-Id: ED74B4001B X-Stat-Signature: qkmnb8wizra54gccf1takn5rmtq17wjd X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1681464846-374550 X-HE-Meta: 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 VRxlG/iI kDS74wepdN96URV0vpphqTherKwJzvqVUOLHqGaSWPXupD0tuS88ICHudx49UV2QkqrLDvgRCOM1vqy2CxA/G8oNiO8AmF5WXiiPC/VTLjuNJjb+sh22e0aVF84W5tXmBluAvfpQNqJeW1Nv6krz7XKqMPMncgzmstIW/UpIL6Jud8zFRblniG7P6iqrIEpJErDUgBglfQo1un/n026oZsPLqFcAuPWs3hp14/purYMuGUZMVk5c2JQh/kmBr9g1P2UhQcNF6i2c5W6JBhbVvU6INCNVCTV4/bLr/d3YiKKritRjLKisSxXYprQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000103, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 13 Apr 2023, Luis Chamberlain wrote: > Simplify the concurrency delimiter we use for kmod with the semaphore. > I had used the kmod strategy to try to implement a similar concurrency > delimiter for the kernel_read*() calls from the finit_module() path > so to reduce vmalloc() memory pressure. That effort didn't provide yet > conclusive results, but one thing that became clear is we can use > the suggested alternative solution with semaphores which Linus hinted > at instead of using the atomic / wait strategy. > > I've stress tested this with kmod test 0008: > > time /data/linux-next/tools/testing/selftests/kmod/kmod.sh -t 0008 > > And I get only a *slight* delay. That delay however is small, a few > seconds for a full test loop run that runs 150 times, for about ~30-40 > seconds. The small delay is worth the simplfication IMHO. > > Signed-off-by: Luis Chamberlain Reviewed-by: Miroslav Benes M