From patchwork Wed May 27 05:24:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11571819 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5845C912 for ; Wed, 27 May 2020 05:24:59 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 37029207ED for ; Wed, 27 May 2020 05:24:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="EPMjuf39" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 37029207ED Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 3DB66122679F5; Tue, 26 May 2020 22:20:50 -0700 (PDT) Received-SPF: None (mailfrom) identity=mailfrom; client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=batv+2c76b185713af36e7087+6121+infradead.org+hch@bombadil.srs.infradead.org; receiver= Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 145A7122679E3 for ; Tue, 26 May 2020 22:20:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=iHue7do6hun8JuTKkSqk6A1cSmWyXJMC7S37LKm+NoE=; b=EPMjuf39RInO9H+7VH8ftwUsNo nBrbMYTAFmxnLpfrZuVpY1ScxzqreAWOBCfaA7t5yKouEBcGkF9zKhgo5jFl18sDpjYO43J7js0Vl Hb6NNOxtLRfEynBwLQdDay3+Um06Dr8ig1m32jrhdmQZtDRCwxnqoBSie14OkjGMbx+mZ0IV03DQP oUDXNo3i728smfUjqtKqSWR4ki3hlV882jwsTd8h58POGiLeciUCsShGrp6BgatfPJG/3XbAAcU4G BvKXGJA002dkPLiBeS7htj5e0awbv+zJCGVKvc8zdxfH/6a3hKVqayJ4HXCmIftDglf8J0L7QRaCO l8BfM76g==; Received: from [2001:4bb8:18c:5da7:8164:affc:3c20:853d] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jdoYe-0000sT-VA; Wed, 27 May 2020 05:24:53 +0000 From: Christoph Hellwig To: Jens Axboe Subject: [PATCH 11/16] block: always use a percpu variable for disk stats Date: Wed, 27 May 2020 07:24:14 +0200 Message-Id: <20200527052419.403583-12-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200527052419.403583-1-hch@lst.de> References: <20200527052419.403583-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Message-ID-Hash: Q2ZQBMGW6BLMVTMWJDLNO7MVWQG2HN6L X-Message-ID-Hash: Q2ZQBMGW6BLMVTMWJDLNO7MVWQG2HN6L X-MailFrom: BATV+2c76b185713af36e7087+6121+infradead.org+hch@bombadil.srs.infradead.org X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Konstantin Khlebnikov , Minchan Kim , Nitin Gupta , dm-devel@redhat.com, linux-block@vger.kernel.org, drbd-dev@lists.linbit.com, linux-bcache@vger.kernel.org, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: percpu variables have a perfectly fine working stub implementation for UP kernels, so use that. Signed-off-by: Christoph Hellwig Reviewed-by: Konstantin Khlebnikov --- block/blk.h | 2 +- block/genhd.c | 12 +++------ block/partitions/core.c | 5 ++-- include/linux/genhd.h | 13 --------- include/linux/part_stat.h | 55 ++++++++------------------------------- 5 files changed, 18 insertions(+), 69 deletions(-) diff --git a/block/blk.h b/block/blk.h index bdf5e94467aa2..0ecba2ab383d6 100644 --- a/block/blk.h +++ b/block/blk.h @@ -378,7 +378,7 @@ static inline void hd_struct_put(struct hd_struct *part) static inline void hd_free_part(struct hd_struct *part) { - free_part_stats(part); + free_percpu(part->dkstats); kfree(part->info); percpu_ref_exit(&part->ref); } diff --git a/block/genhd.c b/block/genhd.c index 094ed90964964..3e7df0a3e6bb0 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -92,7 +92,6 @@ const char *bdevname(struct block_device *bdev, char *buf) } EXPORT_SYMBOL(bdevname); -#ifdef CONFIG_SMP static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) { int cpu; @@ -112,12 +111,6 @@ static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) stat->io_ticks += ptr->io_ticks; } } -#else /* CONFIG_SMP */ -static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) -{ - memcpy(stat, &part->dkstats, sizeof(struct disk_stats)); -} -#endif /* CONFIG_SMP */ static unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) @@ -1688,14 +1681,15 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); if (disk) { - if (!init_part_stats(&disk->part0)) { + disk->part0.dkstats = alloc_percpu(struct disk_stats); + if (!disk->part0.dkstats) { kfree(disk); return NULL; } init_rwsem(&disk->lookup_sem); disk->node_id = node_id; if (disk_expand_part_tbl(disk, 0)) { - free_part_stats(&disk->part0); + free_percpu(disk->part0.dkstats); kfree(disk); return NULL; } diff --git a/block/partitions/core.c b/block/partitions/core.c index 297004fd22648..78951e33b2d7c 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -387,7 +387,8 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno, if (!p) return ERR_PTR(-EBUSY); - if (!init_part_stats(p)) { + p->dkstats = alloc_percpu(struct disk_stats); + if (!p->dkstats) { err = -ENOMEM; goto out_free; } @@ -468,7 +469,7 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno, out_free_info: kfree(p->info); out_free_stats: - free_part_stats(p); + free_percpu(p->dkstats); out_free: kfree(p); return ERR_PTR(err); diff --git a/include/linux/genhd.h b/include/linux/genhd.h index a9384449465a3..f0d6d77309a54 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -39,15 +39,6 @@ extern struct class block_class; #include #include -struct disk_stats { - u64 nsecs[NR_STAT_GROUPS]; - unsigned long sectors[NR_STAT_GROUPS]; - unsigned long ios[NR_STAT_GROUPS]; - unsigned long merges[NR_STAT_GROUPS]; - unsigned long io_ticks; - local_t in_flight[2]; -}; - #define PARTITION_META_INFO_VOLNAMELTH 64 /* * Enough for the string representation of any kind of UUID plus NULL. @@ -72,11 +63,7 @@ struct hd_struct { seqcount_t nr_sects_seq; #endif unsigned long stamp; -#ifdef CONFIG_SMP struct disk_stats __percpu *dkstats; -#else - struct disk_stats dkstats; -#endif struct percpu_ref ref; sector_t alignment_offset; diff --git a/include/linux/part_stat.h b/include/linux/part_stat.h index ece607607a864..6644197980b92 100644 --- a/include/linux/part_stat.h +++ b/include/linux/part_stat.h @@ -4,19 +4,23 @@ #include +struct disk_stats { + u64 nsecs[NR_STAT_GROUPS]; + unsigned long sectors[NR_STAT_GROUPS]; + unsigned long ios[NR_STAT_GROUPS]; + unsigned long merges[NR_STAT_GROUPS]; + unsigned long io_ticks; + local_t in_flight[2]; +}; + /* * Macros to operate on percpu disk statistics: * - * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters - * and should be called between disk_stat_lock() and - * disk_stat_unlock(). + * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters and should + * be called between disk_stat_lock() and disk_stat_unlock(). * * part_stat_read() can be called at any time. - * - * part_stat_{add|set_all}() and {init|free}_part_stats are for - * internal use only. */ -#ifdef CONFIG_SMP #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); }) #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0) @@ -44,43 +48,6 @@ static inline void part_stat_set_all(struct hd_struct *part, int value) sizeof(struct disk_stats)); } -static inline int init_part_stats(struct hd_struct *part) -{ - part->dkstats = alloc_percpu(struct disk_stats); - if (!part->dkstats) - return 0; - return 1; -} - -static inline void free_part_stats(struct hd_struct *part) -{ - free_percpu(part->dkstats); -} - -#else /* !CONFIG_SMP */ -#define part_stat_lock() ({ rcu_read_lock(); 0; }) -#define part_stat_unlock() rcu_read_unlock() - -#define part_stat_get(part, field) ((part)->dkstats.field) -#define part_stat_get_cpu(part, field, cpu) part_stat_get(part, field) -#define part_stat_read(part, field) part_stat_get(part, field) - -static inline void part_stat_set_all(struct hd_struct *part, int value) -{ - memset(&part->dkstats, value, sizeof(struct disk_stats)); -} - -static inline int init_part_stats(struct hd_struct *part) -{ - return 1; -} - -static inline void free_part_stats(struct hd_struct *part) -{ -} - -#endif /* CONFIG_SMP */ - #define part_stat_read_accum(part, field) \ (part_stat_read(part, field[STAT_READ]) + \ part_stat_read(part, field[STAT_WRITE]) + \