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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Arnd Bergmann , Kairui Song , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, Luka Bai X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1777614950; l=1685; i=lukabai@tencent.com; s=20260501; h=from:subject:message-id; bh=l3c8ZOwbATo+2PT4NYOAUghe4sk42dQjWN37S7JdcBg=; b=TSo2qM8r3KPPphClijLCEpGTnjI/pFC9+a8AQTQmdnuguNqhfa6BphAbJgkEVtcBJUMnH5Yi1 ukFPpvM8SE3DKy0cbu0hqLnkQgMtbzyqiZoO3sLbQG5tG9zz+vGRHPR X-Developer-Key: i=lukabai@tencent.com; a=ed25519; pk=KeaVteSWd00GIAjFyWZnuFsKAKixjga1ZkLMcI66nPM= X-Authority-Info-Out: v=2.4 cv=No3cssdJ c=1 sm=1 tr=0 ts=69f4407f cx=c_apl:c_pps:t_out a=qkKslKyYc0ctBTeLUVfTFg==:117 a=IkcTkHD0fZMA:10 a=NGcC8JguVDcA:10 a=x7bEGLp0ZPQA:10 a=UaoJkeuwEpQA:10 a=VkNPw1HP01LnGYTKEx00:22 a=GvQkQWPkAAAA:8 a=JogxrxylMUJFqwMgd1oA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-ORIG-GUID: hB3IhlfY35IDEelkOKd30xeVKZ4dDTn9 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTAxMDA1MyBTYWx0ZWRfX//GBnMBXJ+C+ gHIiUEpz5ykqv7rnL7hYpfRWgqfJ+r3gKMPEjydZWch8zDPRgnyic8lbsqmz7W3j9NORpehDbpm HKuQctCjN/YpeWJWQpUmbYiEkaC5JrIxyy1VYLmK2OeCTZUFp/ZJTLlnSzwEPF9GWO0BvAqBwZH 92Ej9piDwed/XU5gqf3lLyK9lyoPcVTUFAwXQRhq6IyviOvKDCRzX5nIdOLVel7x3tE0paAqprv knKjDu7zC5UVTLsD/eKxfTzl6wKAa+LQOLDzaRlo39GVGxC/5cSWeEIKnzNoLLM02pYqJyPLP3f NLHOvfOkNVMRy2QeQMYWg8GVvr1m0kohvEJxV0b1t4BN80PB9t1gM0vd7O3QsI= X-Proofpoint-GUID: hB3IhlfY35IDEelkOKd30xeVKZ4dDTn9 X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 13A9980003 X-Stat-Signature: 1jf4wocd5mpoenign7y8ujryqqmyoxcb X-Rspam-User: X-HE-Tag: 1777614977-182467 X-HE-Meta: U2FsdGVkX1/t2CDlpwzmizOfERe0aJ5A26TQM101h/6p7lf82zlU61SjDlpLjRuMZ1J2/8EPBgKhWfhuBKFa4C7mqpv41FOZTmYCc1tcS9zAeJmCPy6BqGns4ykNZjmeol+0N6WGjuc1DLZHvLnhj0hr8G0Gqoe6oTEiMxnnLGQnA2nXHkxSvgPkArDXN02VeK0TkDmciWGAlvxWo4NMNC6p5J35qqzptuuf19h2e8isFO40K8Li3PFbqlrWeWDWfuscwL0WLWt4r9MJgKaijyjw4nUZgN0d9QHM2HB63g6yILl0iCPW0Yk8pTIrYjB3SUiD6prZAQFWYUfm9yCbsHUF7Q31RceXP8xtmXgpRymxa4Q6PVubyK38Yae/zanSnfGEZQSzMi2mJFHf3LJOxPPgWKrz9DeBy9k97/jgk5DDq6bsDgY2021MfwoCWtit4eoFUAIMkxaibZzby5+w4wEcmcESpGcXJz7gyPLsXf4/7xkD1ubrUmr8/9ureuq5bRa1MrqUqyqS0U0/LrB2VfTrvzEIvVMNifJQDAkmJt+Szm7UzSuAJGxz40Tp/hIYtW7txWSj+Pl4x7hJhVMZ/z0VPCj5I2ZglKiQjGONnixaOcmQ0xx7uB2GKUiYQnXP05eo56MsQ8zL0XqYmHRHAqShwRrDzX4IV5JVRd8g3iqv/HU6qkLHUUwzmGGqzw4FDirgcYtZ4LKaQz8NhJCZpwHpTgpkAVT7l2KMmocnu87U/LkYsHkPSlZa9KVUQownwobVPNzdHuDh7W2QK+ju8ozCm1+p23q4FXvYfA1AvgL5i+0vbjreARKmHvwp/SWbu+ZrCzVmPkCz3liy4vJkV1fzuP/BwgHN9/c6etaRThPdMzM+h3fAKK2u2eEejRkaq0qEF472QISI2JQHbXz60CX0Akzx9YbfKnBF5tV6VN2q85tIRBinK3WB0kOj6DZIRd/XREccgCDkts8Asik DdFiqjyc boyQg1Oyml0Nh6D2pX9C44ZGUtsWfR20kXE1R8wvMX+AZa+r4OKul++qqAYugQvJvjo/dd+vwok/xj3+K2dPu9M8/xGycXHe7rHCzfkzRLYTOOlzdaqbEnSlDmdChTcf/DMEsI1F+K8zFa0ykOz1hlKTBbGtXaA+ooTkUsq7sNzu4jNdk9kv2s27DOHTVLwD3QvqCp+7vg+6NwUpb/wbL6fI+nOjO9sSBYJhgFdJNsAeRPyaHiGh1++PCl9LJiySoadUmxa4UoYZCl9KgFCPSjHNOh2oae8z/n+wesrj+5AYJqa8ezHdcHnJknHr13cbFUNvKNLZ4fxOGgjE= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Luka Bai We add hugepage_cow_always and hugepage_cow_madvise as two convenient helpers to decide whether we want to do THP COW under each specific circumstance. Also, we add a helper hugepage_cow_enabled to help us know the setup more easily. THP COW is only opened when hugepage is globally enabled or madvise enabled. Signed-off-by: Luka Bai --- include/linux/huge_mm.h | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 2a62f0f92f68..3e5c6da3905b 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -203,6 +203,38 @@ static inline bool hugepage_global_always(void) (1<vm_flags; + + /* anonymous THP need to be enabled first */ + if (!hugepage_global_always() && + (!hugepage_global_enabled() || !(vm_flags & VM_HUGEPAGE))) + return false; + + /* always enables all the THP COW */ + if (hugepage_cow_always()) + return true; + + /* madvise enables THP cow only when vm_flags says so */ + if (hugepage_cow_madvise() && (vm_flags & VM_THP_COW)) + return true; + + return false; +} + static inline int highest_order(unsigned long orders) { return fls_long(orders) - 1; -- 2.52.0