From nobody Sun Feb 8 05:28:33 2026 Received: from mail-yw1-f202.google.com (mail-yw1-f202.google.com [209.85.128.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5DF2E3612CB for ; Thu, 15 Jan 2026 13:06:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768482407; cv=none; b=biAzz1lICwyn84TXbrZDKv3CC1ds0YEZ0XiP1HC8d6T050A6qeZunbwIGjOVI9i5MCIy4bupWje1p8FUz5Nn9a0Cd/ZYI8J+hDLKn3z79kqRM2FDkf2Tg1TD+a3OlXI/bsbhmgaOFFlfKTJawekq17s7qu33uTlhbxfLnSs23gw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768482407; c=relaxed/simple; bh=E4aoSr09u4Tw3uehz3UwiJMDfm7PzTUmaJZ5gZJBRM8=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=o649COocJ9V0FuyRQK9pcBg5VTWwLSFf1pkPiB+3/AIzRZ+GkOZ/njdchzBuY2RBkJECl0/B9JeP4vR5q5vMJnofbK68FPitUAla9EQI4IbX6fxNE4eGxSun22vzK/FNOLjmdqtmEzne1c+HDr34JQNWknX/97RfPjkz2Srzavk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=NlB+PjBa; arc=none smtp.client-ip=209.85.128.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--edumazet.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="NlB+PjBa" Received: by mail-yw1-f202.google.com with SMTP id 00721157ae682-79269803c05so9414047b3.2 for ; Thu, 15 Jan 2026 05:06:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1768482405; x=1769087205; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=xlC4BCwyQxmDdsY0QjKYETsjUCF9cfzvqteRs/cn5KY=; b=NlB+PjBaw9/hSk2BEhCj1VKZQnpZMbVTng5k3JFef9jWraNcD9NuABTXe+RxHj2imV JV+sGqioJyupCzI/9mGvRp9rnljS9ZpHyQojPRzErRkO3ErJBPAfEpF7myPC5H7ZwsBp pGp/Lf7pcNYBJSmMMrD/jr8/Zrv6K7D4LwmiOvNKmObOdrMSS8LW0tDX87RrATmkO07K MyAaun66Q6EM17I48/PIOZYqkSm/LcJ6RPA/MQ+nWPEw0RTeNstCxqP16+HpaDbwiT+K 1BU+U8Y/QkKQ+1bS67r5m54+ks9VpcyhtS6P77CAgwmYBbrcwRAReZq0dFz0Xq0JCZYX foOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1768482405; x=1769087205; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=xlC4BCwyQxmDdsY0QjKYETsjUCF9cfzvqteRs/cn5KY=; b=JG802nZRlexFyz2AO57xQHHdyVanvY7C0RvN1laQ776ffcYYI9swgD5wJLKtTZZcGR sispK8+TQefWnotQPCCmqtlAsIUQ8mvF+dulOwH1/HxsEb1IepYUqmGxeYH1DTmMIHh5 I8vjUFtkFm/hOtdBvl9COndNBWstnKyi7CecEU41Ajbn1q2Zicok4xxBz9u4wPdyrpEg LoFM3deo0+5X9ZtNSwC7HSIy+WS6p5ONu2/p5PNZzxisPDhrrj5/DDnhtZLBBukyaLxX 197FJwsGjTfTP/w1kW9RTYY/wEliDPWddNH/7w4yD68NE4phB9SuLHkClPXO78AuCYVC bpJg== X-Gm-Message-State: AOJu0Yz0u9D+giO3+BfDtRWgop2avYni+S7VpiH4+gpintd8O2sJ/1WX j+sOeOJ4JdkS0BUap7w8IrisCePXlMgcxxBEm1iI/xGjFWkuNSHwf+HcmwxxSlRA+nXgAfNk5CI UH0LQD2dB+gZ4Qg== X-Received: from ywll16.prod.google.com ([2002:a05:690c:a1d0:b0:78f:67fa:b3d6]) (user=edumazet job=prod-delivery.src-stubby-dispatcher) by 2002:a05:690c:101:b0:78f:bede:57fb with SMTP id 00721157ae682-793a1d41185mr47182547b3.49.1768482405052; Thu, 15 Jan 2026 05:06:45 -0800 (PST) Date: Thu, 15 Jan 2026 13:06:42 +0000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.52.0.457.g6b5491de43-goog Message-ID: <20260115130642.3419324-1-edumazet@google.com> Subject: [PATCH] slub: Make sure cache_from_obj() is inlined From: Eric Dumazet To: Vlastimil Babka , Andrew Morton Cc: linux-kernel , Christoph Lameter , David Rientjes , Roman Gushchin , Harry Yoo , Eric Dumazet , Eric Dumazet Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" clang ignores the inline attribute because it thinks cache_from_obj() is too big. Moves the slow path in a separate function (__cache_from_obj()) and use __fastpath_inline to please clang and CONFIG_SLUB_TINY configs. This makes kmem_cache_free() and build_detached_freelist() slightly faster. $ size mm/slub.clang.before.o mm/slub.clang.after.o text data bss dec hex filename 77716 7657 4208 89581 15ded mm/slub.clang.before.o 77766 7673 4208 89647 15e2f mm/slub.clang.after.o $ scripts/bloat-o-meter -t mm/slub.clang.before.o mm/slub.clang.after.o Function old new delta __cache_from_obj - 211 +211 build_detached_freelist 542 569 +27 kmem_cache_free 896 919 +23 cache_from_obj 229 - -229 Signed-off-by: Eric Dumazet --- mm/slub.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/mm/slub.c b/mm/slub.c index 861592ac54257b9d148ff921e6d8f62aced607b3..88a842411c5c3d770ff0070b592= f745832d13d1a 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -6748,15 +6748,10 @@ static inline struct kmem_cache *virt_to_cache(cons= t void *obj) return slab->slab_cache; } =20 -static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void= *x) +static struct kmem_cache *__cache_from_obj(struct kmem_cache *s, void *x) { - struct kmem_cache *cachep; + struct kmem_cache *cachep =3D virt_to_cache(x); =20 - if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && - !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) - return s; - - cachep =3D virt_to_cache(x); if (WARN(cachep && cachep !=3D s, "%s: Wrong slab cache. %s but object is from %s\n", __func__, s->name, cachep->name)) @@ -6764,6 +6759,15 @@ static inline struct kmem_cache *cache_from_obj(stru= ct kmem_cache *s, void *x) return cachep; } =20 +static __fastpath_inline struct kmem_cache *cache_from_obj(struct kmem_cac= he *s, void *x) +{ + if (!IS_ENABLED(CONFIG_SLAB_FREELIST_HARDENED) && + !kmem_cache_debug_flags(s, SLAB_CONSISTENCY_CHECKS)) + return s; + + return __cache_from_obj(s, x); +} + /** * kmem_cache_free - Deallocate an object * @s: The cache the allocation was from. base-commit: 944aacb68baf7624ab8d277d0ebf07f025ca137c --=20 2.52.0.457.g6b5491de43-goog