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charset=us-ascii Content-Disposition: inline In-Reply-To: <4f61457e-deff-430f-8a1e-d3c33c925db3@kernel.org> X-Rspam-User: X-Rspamd-Queue-Id: 17D9280008 X-Rspamd-Server: rspam04 X-Stat-Signature: qatjrh7kp7ujjhpypujpa4mkqygybio8 X-HE-Tag: 1778263662-311614 X-HE-Meta: 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 r07FD+3n Do0voh4UJmiy1wVPCb66PcG/Ws+7tbLFgnK/2rH9y8CcCtRDdjt66PNqjeqVCvOu3BGkj0r9Jo59EsKsOHaSVNDUWfXM7B1I+I0NtEks8HGKQ6IinsL3c2WS8dfgW+ph2DvD9JxlyaJwoD42Gl0uSinfys6TMOKzA93pyvuBJxEZwbZHovh2X5PH+jxxppu4Q0VTeUKvxq1gkCr34o+iec/phHEwHDuUiYLVeVP8S5wPMRv/o0HSxDoAI3le/Jxgtbm1339i6dah5RXnCDxr9RDMItdvxqnnmBiFvy83ESwtpyeG6v5RrwhLb91mmFTZtheMZghkWacT+VtgmrV7fBwlpiXvJfh7X+fHvE42r8XpNRQZ4p1PCqZZ0sBaMgPV1/O8qSJbMKJ9eGVJ7o4zpYnI/tB3vD/V2ZRGW Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, May 08, 2026 at 07:40:51PM +0200, Vlastimil Babka (SUSE) wrote: > On 5/8/26 7:38 PM, Vlastimil Babka (SUSE) wrote: > > On 5/8/26 7:29 PM, Andrew Morton wrote: > >> e .configOn Fri, 8 May 2026 18:22:06 +0200 hawk@kernel.org wrote: > >> > >>> Add tracepoints to the page allocator fast paths that acquire > >>> zone->lock, allowing diagnosis of lock contention in production. > >> > >> Thanks, I'm surprised we haven't done this yet. > > > > There was a recent attempt [1]. Not being a generic solution wasn't welcome. > > > > [1] https://lore.kernel.org/all/cover.1772206930.git.d@ilvokhin.com/ > > And this is the generic solution I think? > > https://lore.kernel.org/all/cover.1777999826.git.d@ilvokhin.com/ Thanks for cc'ing me, Vlastimil. Yes, this is an attempt at a generic solution for tracing contended locks, including spinlocks, so it should also cover the use case proposed in this patchset. In fact, zone->lock contention was one of the primary motivations for this work.