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Sun, 30 Mar 2025 12:17:38 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (unknown [10.72.112.17]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id CEE2B180094A; Sun, 30 Mar 2025 12:17:35 +0000 (UTC) From: Baoquan He To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Baoquan He Subject: [PATCH 3/7] mm/gup: Fix the outdated code comments above get_user_pages_unlocked() Date: Sun, 30 Mar 2025 20:17:13 +0800 Message-ID: <20250330121718.175815-4-bhe@redhat.com> In-Reply-To: <20250330121718.175815-1-bhe@redhat.com> References: <20250330121718.175815-1-bhe@redhat.com> MIME-Version: 1.0 Content-type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 X-Rspamd-Queue-Id: 09BDC180007 X-Stat-Signature: cw3eczz38qi6fkp6rxu4wceyd6mxa38t X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1743337063-409902 X-HE-Meta: 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 1xmZQ5RM 15EXnTX3/GsZDZ3Z5pipkuVDUbktd+1BvWa0mhuzVAFyPI/GSNDd1jSThdPUfitFBjUOJf10XmhUu5jAoBZPkcOncNEiXjG/lb7HTIC4MUEn9sMVYg2CgFVxjq9sImgAUP1uyZrQP95sPJJXxQJMzPZQYLeRtEfiA6niYCfTZgfNkGEdyQFnwJeqboOGiJfLHCARa3gYuhdfUb+zsnZHiir018vSju059IqHDVwJKVSG5obeU7OLCFphS579m5GDfdBk2X6o94IZlG7WU8PXcGGKmKunFwkwskKy6NJSmP4xFm4zqA9zTLvSXIXGPFDRebzfsDWL4ezWqCzyI9SX1p+JQzngvn28HYJUjEUaeZYyI84DzC2orIN/3PMGM4YjAFJY7 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000002, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Since commit f0818f472d8d ("mm: gup: add get_user_pages_locked and get_user_pages_unlocked"), get_user_pages() doesn't need to have mmap_lock held anymore. It calls __get_user_pages_locked() which can acquire and drop the mmap_lock internaly. Hence remove the incorrect code comments now. Signed-off-by: Baoquan He --- mm/gup.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index 8788105daee8..3345a065c2cb 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2702,19 +2702,9 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, EXPORT_SYMBOL(get_user_pages); /* - * get_user_pages_unlocked() is suitable to replace the form: - * - * mmap_read_lock(mm); - * get_user_pages(mm, ..., pages, NULL); - * mmap_read_unlock(mm); - * - * with: - * - * get_user_pages_unlocked(mm, ..., pages); - * - * It is functionally equivalent to get_user_pages_fast so - * get_user_pages_fast should be used instead if specific gup_flags - * (e.g. FOLL_FORCE) are not required. + * get_user_pages_unlocked() is functionally equivalent to + * get_user_pages_fast so get_user_pages_fast should be used instead + * if specific gup_flags (e.g. FOLL_FORCE) are not required. */ long get_user_pages_unlocked(unsigned long start, unsigned long nr_pages, struct page **pages, unsigned int gup_flags)