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tSaTLRf+MNRtv14s0tM40Hf1o/aijYntXmcVHRYVN3JWMwDLGmTukgpoDekOdHd1ljr1Hx0136mIyIm3mQro3kK1P0EIPa1mhROfsHxF9Rcc6dCzVw0Ycgcnn+Uz9bp+3U3Y1D4yWHlo8gPDP6d3EUrHj1fAJ7UpVTk6yDMrXkVZ+jjEghZ/vXkBqOKOaKbSCX3kREITcCcSNEs15nB4Peb5ZFhyXHXnK3PEFDBSCoFAUQQNjI5jXred4z8FERcoAC3ibCnw+niNMM6f0X90s+gyEkkvXiJFy4L2DpA0FRA5+qqwYOwRx3P4linqQwaBzK2KCxROdjPEcUIh4jSGHXBNa/+Mff8XiuQ9y 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: On Wed, Oct 11, 2023 at 10:15:02PM +0100, Matthew Wilcox wrote: > On Mon, Oct 09, 2023 at 04:42:56PM -0400, Gregory Price wrote: > > == Mutex to Semaphore change: > > > > The memory tiering subsystem is extended in this patch set to have > > externally available information (weights), and therefore additional > > controls need to be added to ensure values are not changed (or tiers > > changed/added/removed) during various calculations. > > > > Since it is expected that many threads will be accessing this data > > during allocations, a mutex is not appropriate. > > > > Since write-updates (weight changes, hotplug events) are rare events, > > a simple rw semaphore is sufficient. > > Given how you're using it, wouldn't the existing RCU mechanism be > better than converting this to an rwsem? > ... yes, and a smarter person would have just done that first :P derp derp, thanks, I'll update. ~Gregory