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AJvYcCXoMVtQP0JrPYe392kHWiU5m3yY83w67kDZooxiv1KVDRUNfmBU+puzH+8FWMkiT6QgCDczHOzytg==@kvack.org X-Gm-Message-State: AOJu0Yz9Ik01QY2+EQJjo6uElfK6b1NwZDWCFXDbA5WUVeY1iT0kLJ4u ffBrjDnSzmP4Y1dwD5pPw+dAr+3jZErMU+0oHATmR+AxM2b3LxAi23kykt0UZKSXqjhXfC+a2ip 0T7web0vlD7rw/ptq8mHHbqlfqvQXr80= X-Gm-Gg: AY/fxX71CRseJLvHvxoKVZZpTiNEScFNRJyjYqtaMbZuTZsoGggeCFYqqAYnLEMJ6y/ D5uAMr+4G5oE2RwbBD99zkB7UxQ7gMlP/OlrL29RPhpEKlzcTmEaO2GpXbKCFThNRbQglKFQ0l1 N12G4VH8f2DbKZxqmK49NFnw80aj5rC2E2jjp0XV2Sod4UUcVwWCaukO6E74c7+fPvjyNFgZ2+T T8ANny+HaTNi0OnF/3WpQddkhCON139TITTYFdnF6YdmoK/T2vQP5Fe72A5lqi8qj2EliyWwS6G fsXPEo9XQVOt5fNYIBG/Qe4bB5om X-Received: by 2002:a5d:64c5:0:b0:430:fd0f:2910 with SMTP id ffacd0b85a97d-4342c501a57mr685880f8f.26.1768346824132; Tue, 13 Jan 2026 15:27:04 -0800 (PST) MIME-Version: 1.0 References: <20260112-sheaves-for-all-v2-0-98225cfb50cf@suse.cz> <20260112-sheaves-for-all-v2-6-98225cfb50cf@suse.cz> <20260113183604.ykHFYvV2@linutronix.de> In-Reply-To: <20260113183604.ykHFYvV2@linutronix.de> From: Alexei Starovoitov Date: Tue, 13 Jan 2026 15:26:53 -0800 X-Gm-Features: AZwV_Qg0xd2SuSeZtzkfObEmnG4DkzskoYODoJFcrxj4bx-h7Wvm-bafCffVqCQ Message-ID: Subject: Re: [PATCH RFC v2 06/20] slab: make percpu sheaves compatible with kmalloc_nolock()/kfree_nolock() To: Sebastian Andrzej Siewior Cc: Vlastimil Babka , Harry Yoo , Petr Tesarik , Christoph Lameter , David Rientjes , Roman Gushchin , Hao Li , Andrew Morton , Uladzislau Rezki , "Liam R. Howlett" , Suren Baghdasaryan , Alexei Starovoitov , linux-mm , LKML , linux-rt-devel@lists.linux.dev, bpf , kasan-dev Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: E8A04A0003 X-Rspam-User: X-Stat-Signature: n8ucatqnbqbcj7aym67ytm91cagc4be7 X-HE-Tag: 1768346825-242567 X-HE-Meta: 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 SbXHTo12 H4r6glMadFGN+6G8aGA68tU2+YFSCR4nVzehcMwuCWg3h6XkmNc52rZcoDlbgE41GS0j4qCGyWimCKvagLj15vQLWdsoKAJfKkm8Hb/Snzcll3SBR3FbZCIYCadRbxQlVwsD+IPMkS0FTqqa00VeQxvlLs/3gs/J0YIaHkfFtiFYlrUom8CAde3Di5J1VtV4qnndxnrQYRxpYlInz3vy7a6xBaFY1J7OT/pSst4p4GvSbmh/xdCkWOouwgvqvDxLKq6Yko64NI6rOAt2fPqy1Odsbuv3s9Kio702xqb6gkCAU8tYDyZ2bORJt2mjutmQZWrP5KSJpNxRBd7sGmyDBToYh6GnMhvVKw/F83XwHEzzCmEdoq00BxNqJFxA/mImbNf9HKMAtLyz4QRVslaA6ccIiy0IsvQ+r7Ikn38H6Fr+6mAF2NhtDkAiSKMfsdm12YBf9+RgSNXdAyPkuwbEdmd7vm5pepIk0Wihih3AmEtnhWts= 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 Tue, Jan 13, 2026 at 10:36=E2=80=AFAM Sebastian Andrzej Siewior wrote: > > On 2026-01-12 16:17:00 [+0100], Vlastimil Babka wrote: > > --- a/mm/slub.c > > +++ b/mm/slub.c > > @@ -5727,6 +5742,12 @@ void *kmalloc_nolock_noprof(size_t size, gfp_t g= fp_flags, int node) > > */ > > return NULL; > > > > + ret =3D alloc_from_pcs(s, alloc_gfp, node); > > + if (ret) > > + goto success; > > I'm sorry if I am slow but this actually should actually allow > kmalloc_nolock() allocations on PREEMPT_RT from atomic context. I am > mentioning this because of the patch which removes the nmi+hardirq > condtion (https://lore.kernel.org/all/20260113150639.48407-1-swarajgaikwa= d1925@gmail.com) Right. With sheaves kmalloc_nolock() on RT will be more reliable.