From nobody Tue Feb 10 16:02:09 2026 Received: from mailrelay-egress12.pub.mailoutpod2-cph3.one.com (mailrelay-egress12.pub.mailoutpod2-cph3.one.com [46.30.211.187]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A673293C7C for ; Thu, 26 Jun 2025 08:36:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=46.30.211.187 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750927000; cv=none; b=dfkn9oKWsBjVSe/k4DFVWyixkISk1KMffObrbb1zotoEoUTq6kkWuNF6/lFJzqd/PZh4vqaFpPHW+QF8yvQipstZDDcqz67tfD+v2AO0lnNDX854Pkfv4jBLfO/dkMYimaqn3e8/7XEeuuSo630wx6mxdvvj0SAtQZPQPQrScPc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750927000; c=relaxed/simple; bh=7YJuPkik1KBD4lbPP0cuZ1cG07RJnRRNZjS8MiZCo2w=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=eTa1BiiaRHDYK6MOZ01zM+DMUI294PRpuz5rmt0t1yLpUUUjaTF0u+qQ0DIH7Q7fMlpLzuRuPyyONKh4iTMo7CbcgDLC0syCKWueDiDxDM0ZNhyerEx2qK8saIQeXsJQraypwVVZQUp8c8E4ABzntnjvKqla+LgFnIzszhK55pU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=konsulko.se; spf=none smtp.mailfrom=konsulko.se; dkim=pass (2048-bit key) header.d=konsulko.se header.i=@konsulko.se header.b=MaS7+d3L; dkim=permerror (0-bit key) header.d=konsulko.se header.i=@konsulko.se header.b=qnY2tAg/; arc=none smtp.client-ip=46.30.211.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=konsulko.se Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=konsulko.se Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=konsulko.se header.i=@konsulko.se header.b="MaS7+d3L"; dkim=permerror (0-bit key) header.d=konsulko.se header.i=@konsulko.se header.b="qnY2tAg/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1750926995; x=1751531795; d=konsulko.se; s=rsa1; h=content-transfer-encoding:mime-version:references:in-reply-to:message-id:date: subject:cc:to:from:from; bh=Q5e5J6xYEr32Saw5MlCRa9dyPVfRH3gV92WpTITaL6o=; b=MaS7+d3L0+J4gcShT3GTbAbNh5ouzKp+jOaPmM0g+E+7fLZVh6GgLfaeu+UosCXCzM9R0y8gixXA4 eNfqL+pMtCT6Pj+vfp5hcRW2RyZX9DXhO5iq+KDhMiWNQUE4yTsuqIyagAgWW5gsWsXMVIXBVsIHEw lL7alYl0yFc4kW4E3zCaI7k7PQhS6onHggDC446DlYqAUo7VLRU/hRt2BM3BubhtVGJWzPRjzEU9ts CbOB5SxwUOKyIBTsHrqQNe8RuBby/DA8uiPVFxCojeZcxXXN/B7F6gGzs+GPAU8svugc+JxVasZFAw Nb2GeCwPgU4K5jRrij+MJ3uq7qC3iWQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; t=1750926995; x=1751531795; d=konsulko.se; s=ed1; h=content-transfer-encoding:mime-version:references:in-reply-to:message-id:date: subject:cc:to:from:from; bh=Q5e5J6xYEr32Saw5MlCRa9dyPVfRH3gV92WpTITaL6o=; b=qnY2tAg/vZxKCqbs9EOFAShQHto+WqH5SYbgnc7coU/nZHRzgBwuwh6CbUt4Abl7Jj1kEKetkd4gI v6O2GoJCg== X-HalOne-ID: a964cd49-5268-11f0-9a7d-4f541c8bf1cc Received: from localhost.localdomain (host-90-238-19-233.mobileonline.telia.com [90.238.19.233]) by mailrelay3.pub.mailoutpod2-cph3.one.com (Halon) with ESMTPSA id a964cd49-5268-11f0-9a7d-4f541c8bf1cc; Thu, 26 Jun 2025 08:36:34 +0000 (UTC) From: Vitaly Wool To: linux-mm@kvack.org Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, Uladzislau Rezki , Danilo Krummrich , Alice Ryhl , rust-for-linux@vger.kernel.org, Vitaly Wool Subject: [PATCH v4 2/4] mm/slub: allow to set node and align in k[v]realloc Date: Thu, 26 Jun 2025 10:36:32 +0200 Message-Id: <20250626083632.3596363-1-vitaly.wool@konsulko.se> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20250626083516.3596197-1-vitaly.wool@konsulko.se> References: <20250626083516.3596197-1-vitaly.wool@konsulko.se> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Reimplement k[v]realloc() to be able to set node and alignment should a user need to do so. Rename the respective functions to k[v]realloc_node() to better match what they actually do now and introduce macros for k[v]realloc() for backward compatibility. With that change we also provide the ability for the Rust part of the kernel to set node and aligmnent in its K[v]xxx [re]allocations. Signed-off-by: Vitaly Wool --- include/linux/slab.h | 12 ++++++++---- mm/slub.c | 33 ++++++++++++++++++++++----------- 2 files changed, 30 insertions(+), 15 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index d5a8ab98035c..119f100978c8 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -465,9 +465,11 @@ int kmem_cache_shrink(struct kmem_cache *s); /* * Common kmalloc functions provided by all allocators */ -void * __must_check krealloc_noprof(const void *objp, size_t new_size, - gfp_t flags) __realloc_size(2); -#define krealloc(...) alloc_hooks(krealloc_noprof(__VA_ARGS__)) +void * __must_check krealloc_node_noprof(const void *objp, size_t new_size, + gfp_t flags, int nid) __realloc_size(2); +#define krealloc_node(...) alloc_hooks(krealloc_node_noprof(__VA_ARGS__)) +#define krealloc_noprof(o, s, f) krealloc_node_noprof(o, s, f, NUMA_NO_NOD= E) +#define krealloc(...) alloc_hooks(krealloc_noprof(__VA_ARGS__)) =20 void kfree(const void *objp); void kfree_sensitive(const void *objp); @@ -1073,8 +1075,10 @@ kvmalloc_array_node_noprof(size_t n, size_t size, gf= p_t flags, int node) #define kvcalloc_node(...) alloc_hooks(kvcalloc_node_noprof(__VA_ARGS__)) #define kvcalloc(...) alloc_hooks(kvcalloc_noprof(__VA_ARGS__)) =20 -void *kvrealloc_noprof(const void *p, size_t size, gfp_t flags) +void *kvrealloc_node_noprof(const void *p, size_t size, gfp_t flags, int n= id) __realloc_size(2); +#define kvrealloc_node(...) alloc_hooks(kvrealloc_node_noprof(__VA_ARGS_= _)) +#define kvrealloc_noprof(p, s, f) kvrealloc_node_noprof(p, s, f, NUMA_NO_= NODE) #define kvrealloc(...) alloc_hooks(kvrealloc_noprof(__VA_ARGS__)) =20 extern void kvfree(const void *addr); diff --git a/mm/slub.c b/mm/slub.c index c4b64821e680..2d5150d075d5 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -4845,7 +4845,7 @@ void kfree(const void *object) EXPORT_SYMBOL(kfree); =20 static __always_inline __realloc_size(2) void * -__do_krealloc(const void *p, size_t new_size, gfp_t flags) +__do_krealloc(const void *p, size_t new_size, gfp_t flags, int nid) { void *ret; size_t ks =3D 0; @@ -4859,6 +4859,15 @@ __do_krealloc(const void *p, size_t new_size, gfp_t = flags) if (!kasan_check_byte(p)) return NULL; =20 + /* + * it is possible to support reallocation with a different nid, but + * it doesn't go well with the concept of krealloc(). Such + * reallocation should be done explicitly instead. + */ + if (WARN(nid !=3D NUMA_NO_NODE && nid !=3D page_to_nid(virt_to_page(p)), + "krealloc() has mismatched nids\n")) + return NULL; + if (is_kfence_address(p)) { ks =3D orig_size =3D kfence_ksize(p); } else { @@ -4903,7 +4912,7 @@ __do_krealloc(const void *p, size_t new_size, gfp_t f= lags) return (void *)p; =20 alloc_new: - ret =3D kmalloc_node_track_caller_noprof(new_size, flags, NUMA_NO_NODE, _= RET_IP_); + ret =3D kmalloc_node_track_caller_noprof(new_size, flags, nid, _RET_IP_); if (ret && p) { /* Disable KASAN checks as the object's redzone is accessed. */ kasan_disable_current(); @@ -4919,6 +4928,7 @@ __do_krealloc(const void *p, size_t new_size, gfp_t f= lags) * @p: object to reallocate memory for. * @new_size: how many bytes of memory are required. * @flags: the type of memory to allocate. + * @nid: NUMA node or NUMA_NO_NODE * * If @p is %NULL, krealloc() behaves exactly like kmalloc(). If @new_size * is 0 and @p is not a %NULL pointer, the object pointed to is freed. @@ -4947,7 +4957,7 @@ __do_krealloc(const void *p, size_t new_size, gfp_t f= lags) * * Return: pointer to the allocated memory or %NULL in case of error */ -void *krealloc_noprof(const void *p, size_t new_size, gfp_t flags) +void *krealloc_node_noprof(const void *p, size_t new_size, gfp_t flags, in= t nid) { void *ret; =20 @@ -4956,13 +4966,13 @@ void *krealloc_noprof(const void *p, size_t new_siz= e, gfp_t flags) return ZERO_SIZE_PTR; } =20 - ret =3D __do_krealloc(p, new_size, flags); + ret =3D __do_krealloc(p, new_size, flags, nid); if (ret && kasan_reset_tag(p) !=3D kasan_reset_tag(ret)) kfree(p); =20 return ret; } -EXPORT_SYMBOL(krealloc_noprof); +EXPORT_SYMBOL(krealloc_node_noprof); =20 static gfp_t kmalloc_gfp_adjust(gfp_t flags, size_t size) { @@ -5079,10 +5089,11 @@ void kvfree_sensitive(const void *addr, size_t len) EXPORT_SYMBOL(kvfree_sensitive); =20 /** - * kvrealloc - reallocate memory; contents remain unchanged + * kvrealloc_node - reallocate memory; contents remain unchanged * @p: object to reallocate memory for * @size: the size to reallocate * @flags: the flags for the page level allocator + * @nid: NUMA node id * * If @p is %NULL, kvrealloc() behaves exactly like kvmalloc(). If @size i= s 0 * and @p is not a %NULL pointer, the object pointed to is freed. @@ -5100,17 +5111,17 @@ EXPORT_SYMBOL(kvfree_sensitive); * * Return: pointer to the allocated memory or %NULL in case of error */ -void *kvrealloc_noprof(const void *p, size_t size, gfp_t flags) +void *kvrealloc_node_noprof(const void *p, size_t size, gfp_t flags, int n= id) { void *n; =20 if (is_vmalloc_addr(p)) - return vrealloc_noprof(p, size, flags); + return vrealloc_node_noprof(p, size, 1, flags, nid); =20 - n =3D krealloc_noprof(p, size, kmalloc_gfp_adjust(flags, size)); + n =3D krealloc_node_noprof(p, size, kmalloc_gfp_adjust(flags, size), nid); if (!n) { /* We failed to krealloc(), fall back to kvmalloc(). */ - n =3D kvmalloc_noprof(size, flags); + n =3D kvmalloc_node_noprof(size, flags, nid); if (!n) return NULL; =20 @@ -5126,7 +5137,7 @@ void *kvrealloc_noprof(const void *p, size_t size, gf= p_t flags) =20 return n; } -EXPORT_SYMBOL(kvrealloc_noprof); +EXPORT_SYMBOL(kvrealloc_node_noprof); =20 struct detached_freelist { struct slab *slab; --=20 2.39.2