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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: DD94C1C0004 X-Stat-Signature: yt6gacq9em36jjcescfjwp3g1djp5gzu X-Rspam-User: X-HE-Tag: 1738044670-575443 X-HE-Meta: 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 dZ7HxQ5t 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 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 Fri, Jan 24, 2025 at 07:21:27PM +0800, yangge1116@126.com wrote: > From: yangge > > Commit 60a60e32cf91 ("Revert "mm/cma.c: remove redundant cma_mutex lock"") > simply reverts to the original method of using the cma_mutex to ensure > that alloc_contig_range() runs sequentially. This change was made to avoid > concurrency allocation failures. However, it can negatively impact > performance when concurrent allocation of CMA memory is required. > > To address this issue, we could introduce an API for concurrency settings, > allowing users to decide whether their CMA can perform concurrent memory > allocations or not. > > Fixes: 60a60e32cf91 ("Revert "mm/cma.c: remove redundant cma_mutex lock"") > Signed-off-by: yangge > Cc: Umm, you're adding new unused functions while not even reporting what the problem is. This looks sketchy as hell and surely is not a stable candidate.