From nobody Thu Dec 18 18:00:43 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 A3C7C190661 for ; Tue, 30 Apr 2024 14:01:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714485718; cv=none; b=d+DjN4o7uai8pf039sPHHWRfo0SKCzlRu1mLtG3A8uJzEGe+1noofbnuTla/OyBKm8CgjatsQP7pVNgRdLoifZWK1V9iu8PxUy7OIG2zqk8I7ugzW4/MUwipvvUsFlmrXprEJO8gH8ardVKoJnog5fUXBYkZ0YvDLqpyqZPJJ7k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714485718; c=relaxed/simple; bh=k7butF2E3M5C92rNJOBuk0ayz9QDvlWgyRICJgRL0vo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VbfkcXPScsV4Y2VpJtMH8OjtTzbbE3gAPx5Efv0lDH5K7Pen0DktNnlr4hhAgnxfDPTCv0k3U9uRTEEH/70VyBP1DWLJ/NDLzsjR1J5wm912TD2wKgI1h9oCQKMbJoS8N0rjk+VwlHCgt8NhwaOTJeDbIZJ3lzBkBec8Qo6++rA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Qs2Nyil8; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Qs2Nyil8" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1714485715; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gjD+U3QAvMJsWp5JWtEGQmPuhzWaXONmtLXPtsHvH4g=; b=Qs2Nyil8vE22U0HQUHSn/KwApKRM43nQplp0WjD1w9U1E9PsgFIAslO6wYeydmuH1hZWUl rfwEBhnU3Cti3OctiBAUbeLzkhrLWDkcUiXzlzj+XrAHawYdX57tDfHu0EWL6thhdON2k7 KdSk0YP8x4JpiVW2W47gsXIIotSbLGs= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-630-DVP6iI7mM5u1xsuiWmwWLg-1; Tue, 30 Apr 2024 10:01:49 -0400 X-MC-Unique: DVP6iI7mM5u1xsuiWmwWLg-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2227C104B50C; Tue, 30 Apr 2024 14:01:48 +0000 (UTC) Received: from warthog.procyon.org.com (unknown [10.42.28.22]) by smtp.corp.redhat.com (Postfix) with ESMTP id 38BD1492BC7; Tue, 30 Apr 2024 14:01:45 +0000 (UTC) From: David Howells To: Christian Brauner , Jeff Layton , Gao Xiang , Dominique Martinet Cc: David Howells , Matthew Wilcox , Steve French , Marc Dionne , Paulo Alcantara , Shyam Prasad N , Tom Talpey , Eric Van Hensbergen , Ilya Dryomov , netfs@lists.linux.dev, linux-cachefs@redhat.com, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs@lists.linux.dev, linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 11/22] netfs: Use mempools for allocating requests and subrequests Date: Tue, 30 Apr 2024 15:00:42 +0100 Message-ID: <20240430140056.261997-12-dhowells@redhat.com> In-Reply-To: <20240430140056.261997-1-dhowells@redhat.com> References: <20240430140056.261997-1-dhowells@redhat.com> 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 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 Content-Type: text/plain; charset="utf-8" Use mempools for allocating requests and subrequests in an effort to make sure that allocation always succeeds so that when performing writeback we can always make progress. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org --- fs/netfs/internal.h | 2 ++ fs/netfs/main.c | 51 ++++++++++++++++++++++++++++++++----- fs/netfs/objects.c | 59 ++++++++++++++++++++++++++++--------------- include/linux/netfs.h | 5 ++-- 4 files changed, 89 insertions(+), 28 deletions(-) diff --git a/fs/netfs/internal.h b/fs/netfs/internal.h index 156ab138e224..c67da478cd2b 100644 --- a/fs/netfs/internal.h +++ b/fs/netfs/internal.h @@ -37,6 +37,8 @@ int netfs_begin_read(struct netfs_io_request *rreq, bool = sync); extern unsigned int netfs_debug; extern struct list_head netfs_io_requests; extern spinlock_t netfs_proc_lock; +extern mempool_t netfs_request_pool; +extern mempool_t netfs_subrequest_pool; =20 #ifdef CONFIG_PROC_FS static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) diff --git a/fs/netfs/main.c b/fs/netfs/main.c index 844efbb2e7a2..4805b9377364 100644 --- a/fs/netfs/main.c +++ b/fs/netfs/main.c @@ -7,6 +7,7 @@ =20 #include #include +#include #include #include #include "internal.h" @@ -23,6 +24,11 @@ unsigned netfs_debug; module_param_named(debug, netfs_debug, uint, S_IWUSR | S_IRUGO); MODULE_PARM_DESC(netfs_debug, "Netfs support debugging mask"); =20 +static struct kmem_cache *netfs_request_slab; +static struct kmem_cache *netfs_subrequest_slab; +mempool_t netfs_request_pool; +mempool_t netfs_subrequest_pool; + #ifdef CONFIG_PROC_FS LIST_HEAD(netfs_io_requests); DEFINE_SPINLOCK(netfs_proc_lock); @@ -98,25 +104,54 @@ static int __init netfs_init(void) { int ret =3D -ENOMEM; =20 + netfs_request_slab =3D kmem_cache_create("netfs_request", + sizeof(struct netfs_io_request), 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, + NULL); + if (!netfs_request_slab) + goto error_req; + + if (mempool_init_slab_pool(&netfs_request_pool, 100, netfs_request_slab) = < 0) + goto error_reqpool; + + netfs_subrequest_slab =3D kmem_cache_create("netfs_subrequest", + sizeof(struct netfs_io_subrequest), 0, + SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, + NULL); + if (!netfs_subrequest_slab) + goto error_subreq; + + if (mempool_init_slab_pool(&netfs_subrequest_pool, 100, netfs_subrequest_= slab) < 0) + goto error_subreqpool; + if (!proc_mkdir("fs/netfs", NULL)) - goto error; + goto error_proc; if (!proc_create_seq("fs/netfs/requests", S_IFREG | 0444, NULL, &netfs_requests_seq_ops)) - goto error_proc; + goto error_procfile; #ifdef CONFIG_FSCACHE_STATS if (!proc_create_single("fs/netfs/stats", S_IFREG | 0444, NULL, netfs_stats_show)) - goto error_proc; + goto error_procfile; #endif =20 ret =3D fscache_init(); if (ret < 0) - goto error_proc; + goto error_fscache; return 0; =20 -error_proc: +error_fscache: +error_procfile: remove_proc_entry("fs/netfs", NULL); -error: +error_proc: + mempool_exit(&netfs_subrequest_pool); +error_subreqpool: + kmem_cache_destroy(netfs_subrequest_slab); +error_subreq: + mempool_exit(&netfs_request_pool); +error_reqpool: + kmem_cache_destroy(netfs_request_slab); +error_req: return ret; } fs_initcall(netfs_init); @@ -125,5 +160,9 @@ static void __exit netfs_exit(void) { fscache_exit(); remove_proc_entry("fs/netfs", NULL); + mempool_exit(&netfs_subrequest_pool); + kmem_cache_destroy(netfs_subrequest_slab); + mempool_exit(&netfs_request_pool); + kmem_cache_destroy(netfs_request_slab); } module_exit(netfs_exit); diff --git a/fs/netfs/objects.c b/fs/netfs/objects.c index 8acc03a64059..1a4e2ce735ce 100644 --- a/fs/netfs/objects.c +++ b/fs/netfs/objects.c @@ -6,6 +6,8 @@ */ =20 #include +#include +#include #include "internal.h" =20 /* @@ -20,17 +22,22 @@ struct netfs_io_request *netfs_alloc_request(struct add= ress_space *mapping, struct inode *inode =3D file ? file_inode(file) : mapping->host; struct netfs_inode *ctx =3D netfs_inode(inode); struct netfs_io_request *rreq; + mempool_t *mempool =3D ctx->ops->request_pool ?: &netfs_request_pool; + struct kmem_cache *cache =3D mempool->pool_data; bool is_unbuffered =3D (origin =3D=3D NETFS_UNBUFFERED_WRITE || origin =3D=3D NETFS_DIO_READ || origin =3D=3D NETFS_DIO_WRITE); bool cached =3D !is_unbuffered && netfs_is_cache_enabled(ctx); int ret; =20 - rreq =3D kzalloc(ctx->ops->io_request_size ?: sizeof(struct netfs_io_requ= est), - GFP_KERNEL); - if (!rreq) - return ERR_PTR(-ENOMEM); + for (;;) { + rreq =3D mempool_alloc(mempool, GFP_KERNEL); + if (rreq) + break; + msleep(10); + } =20 + memset(rreq, 0, kmem_cache_size(cache)); rreq->start =3D start; rreq->len =3D len; rreq->upper_len =3D len; @@ -56,7 +63,7 @@ struct netfs_io_request *netfs_alloc_request(struct addre= ss_space *mapping, if (rreq->netfs_ops->init_request) { ret =3D rreq->netfs_ops->init_request(rreq, file); if (ret < 0) { - kfree(rreq); + mempool_free(rreq, rreq->netfs_ops->request_pool ?: &netfs_request_pool= ); return ERR_PTR(ret); } } @@ -88,6 +95,14 @@ void netfs_clear_subrequests(struct netfs_io_request *rr= eq, bool was_async) } } =20 +static void netfs_free_request_rcu(struct rcu_head *rcu) +{ + struct netfs_io_request *rreq =3D container_of(rcu, struct netfs_io_reque= st, rcu); + + mempool_free(rreq, rreq->netfs_ops->request_pool ?: &netfs_request_pool); + netfs_stat_d(&netfs_n_rh_rreq); +} + static void netfs_free_request(struct work_struct *work) { struct netfs_io_request *rreq =3D @@ -110,8 +125,7 @@ static void netfs_free_request(struct work_struct *work) } kvfree(rreq->direct_bv); } - kfree_rcu(rreq, rcu); - netfs_stat_d(&netfs_n_rh_rreq); + call_rcu(&rreq->rcu, netfs_free_request_rcu); } =20 void netfs_put_request(struct netfs_io_request *rreq, bool was_async, @@ -143,20 +157,25 @@ void netfs_put_request(struct netfs_io_request *rreq,= bool was_async, struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request= *rreq) { struct netfs_io_subrequest *subreq; - - subreq =3D kzalloc(rreq->netfs_ops->io_subrequest_size ?: - sizeof(struct netfs_io_subrequest), - GFP_KERNEL); - if (subreq) { - INIT_WORK(&subreq->work, NULL); - INIT_LIST_HEAD(&subreq->rreq_link); - refcount_set(&subreq->ref, 2); - subreq->rreq =3D rreq; - subreq->debug_index =3D atomic_inc_return(&rreq->subreq_counter); - netfs_get_request(rreq, netfs_rreq_trace_get_subreq); - netfs_stat(&netfs_n_rh_sreq); + mempool_t *mempool =3D rreq->netfs_ops->subrequest_pool ?: &netfs_subrequ= est_pool; + struct kmem_cache *cache =3D mempool->pool_data; + + for (;;) { + subreq =3D mempool_alloc(rreq->netfs_ops->subrequest_pool ?: &netfs_subr= equest_pool, + GFP_KERNEL); + if (subreq) + break; + msleep(10); } =20 + memset(subreq, 0, kmem_cache_size(cache)); + INIT_WORK(&subreq->work, NULL); + INIT_LIST_HEAD(&subreq->rreq_link); + refcount_set(&subreq->ref, 2); + subreq->rreq =3D rreq; + subreq->debug_index =3D atomic_inc_return(&rreq->subreq_counter); + netfs_get_request(rreq, netfs_rreq_trace_get_subreq); + netfs_stat(&netfs_n_rh_sreq); return subreq; } =20 @@ -178,7 +197,7 @@ static void netfs_free_subrequest(struct netfs_io_subre= quest *subreq, trace_netfs_sreq(subreq, netfs_sreq_trace_free); if (rreq->netfs_ops->free_subrequest) rreq->netfs_ops->free_subrequest(subreq); - kfree(subreq); + mempool_free(subreq, rreq->netfs_ops->subrequest_pool ?: &netfs_subreques= t_pool); netfs_stat_d(&netfs_n_rh_sreq); netfs_put_request(rreq, was_async, netfs_rreq_trace_put_subreq); } diff --git a/include/linux/netfs.h b/include/linux/netfs.h index 3af589dabd7f..0b6c2c2d3c23 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -20,6 +20,7 @@ #include =20 enum netfs_sreq_ref_trace; +typedef struct mempool_s mempool_t; =20 /** * folio_start_private_2 - Start an fscache write on a folio. [DEPRECATED] @@ -236,8 +237,8 @@ struct netfs_io_request { * Operations the network filesystem can/must provide to the helpers. */ struct netfs_request_ops { - unsigned int io_request_size; /* Alloc size for netfs_io_request struct */ - unsigned int io_subrequest_size; /* Alloc size for netfs_io_subrequest st= ruct */ + mempool_t *request_pool; + mempool_t *subrequest_pool; int (*init_request)(struct netfs_io_request *rreq, struct file *file); void (*free_request)(struct netfs_io_request *rreq); void (*free_subrequest)(struct netfs_io_subrequest *rreq);