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charset="UTF-8" X-Stat-Signature: 3atpqddic9j1dfgbgo95k846heaper7q X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 246F31C0014 X-Rspam-User: X-HE-Tag: 1765991969-288166 X-HE-Meta: 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 +NzlWAAB 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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: >> From 4c6b4d4cb08aee9559d02a348b9ecf799142c96f Mon Sep 17 00:00:00 2001 >> From: Brendan Jackman >> Date: Wed, 17 Dec 2025 13:26:28 +0000 >> Subject: [PATCH] mm: clarify GFP_ATOMIC/GFP_NOWAIT doc-comment >> >> The current description of contexts where it's invalid to make >> GFP_ATOMIC and GFP_NOWAIT calls is rather vague. >> >> Replace this with a direct description of the actual contexts of concern >> and refer to the RT docs where this is explained more discursively. >> >> While rejigging this prose, also move the documentation of GFP_NOWAIT to >> the GFP_NOWAIT section. > > There doesn't seem to be any move? This is referring to [0] and [1]. >> diff --git a/include/linux/gfp_types.h b/include/linux/gfp_types.h >> index 3de43b12209ee..07a378542caf2 100644 >> --- a/include/linux/gfp_types.h >> +++ b/include/linux/gfp_types.h >> @@ -309,8 +309,10 @@ enum { >> * >> * %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower >> * watermark is applied to allow access to "atomic reserves". >> - * The current implementation doesn't support NMI and few other strict >> - * non-preemptive contexts (e.g. raw_spin_lock). The same applies to %GFP_NOWAIT. [0] ^^^^^^^^^^^^^^^^^^^^^^^^^^ >> + * The current implementation doesn't support NMI, nor contexts that disable >> + * preemption under PREEMPT_RT. This includes raw_spin_lock() and plain >> + * preempt_disable() - see Documentation/core-api/real-time/differences.rst for >> + * more info. > > Can we reference the "Memory allocation" section directly? Yeah good point. I will send this as a standalone [PATCH] mail tomorrow. >> * >> * %GFP_KERNEL is typical for kernel-internal allocations. The caller requires >> * %ZONE_NORMAL or a lower zone for direct access but can direct reclaim. >> @@ -321,6 +323,7 @@ enum { >> * %GFP_NOWAIT is for kernel allocations that should not stall for direct >> * reclaim, start physical IO or use any filesystem callback. It is very >> * likely to fail to allocate memory, even for very small allocations. >> + * The same restrictions on calling contexts apply as for %GFP_ATOMIC. [1] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^