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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: AEFC11C0007 X-Stat-Signature: gi4gifhx97yjsqbs3yd8jw7z5y9r8kky X-Rspam-User: X-HE-Tag: 1738535367-307757 X-HE-Meta: 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 vAcukeip KtER8pOVxcm/t/h2FiATUPCpA1taUraXc3VmYelH6I+wKGEKU3w2xufUVL6H2ky0jqhKoh2WnxnXf2cnA+grnwi4vSYhX1Pb7yfYMtgPMdrnMrZpmSUCQjIJcecWpUSzzVAAMwMV15tOmwOTy2S7g/48Y5bGuLsLmGKYNplrO2TWCUId1whHzx4ba0xwPY1XDdepTXxp8ia7QC8qkYhduXLDsq+DyCapNWtd3Ac0rrkZ9IMcY8yshUcdz7WiQYUu4uvI73Sh5+VUIrjq6JbwX9tfhbzJDkBWOzq9ampJ0iheQccV3e1eH6GgxO237M4IC1DNIQg5SGqJ1QroiDiJxaBhXSdaqa1Ck3aeDjUVvromJMUN/OEtKVz1zEQ== 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 Sun, 2 Feb 2025 07:22:08 +0000 Matthew Wilcox wrote: > On Sat, Feb 01, 2025 at 10:22:08PM -0500, Steven Rostedt wrote: > > And before seeing Peter's use of yield(), I was reluctant to use it for > > the very same reasons you mentioned above. In my test programs, I was > > simply using getuid(), as that was one of the quickest syscalls. > > Is getuid() guaranteed to issue a syscall? It feels like the kind of > information that a tricksy libc could cache. Traditionally, I think > we've used getppid() as the canonical "very cheap syscall" as no layer > can cache that information. Maybe that was what I used. Can't remember. And I think I even open coded it using syscall() to not even rely on glibc. -- Steve