Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754102AbaKXNXH (ORCPT ); Mon, 24 Nov 2014 08:23:07 -0500 Received: from mail.sigma-star.at ([95.130.255.111]:14387 "EHLO mail.sigma-star.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753572AbaKXNUr (ORCPT ); Mon, 24 Nov 2014 08:20:47 -0500 From: Richard Weinberger To: dedekind1@gmail.com Cc: linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, Richard Weinberger Subject: [PATCH 2/6] UBI: Fastmap: Ensure that only one fastmap work is scheduled Date: Mon, 24 Nov 2014 14:20:32 +0100 Message-Id: <1416835236-25185-3-git-send-email-richard@nod.at> X-Mailer: git-send-email 1.8.4.5 In-Reply-To: <1416835236-25185-1-git-send-email-richard@nod.at> References: <1416835236-25185-1-git-send-email-richard@nod.at> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the WL pool runs out of PEBs we schedule a fastmap write to refill it as soon as possible. Ensure that only one at a time is scheduled otherwise we might end in a fastmap write storm because writing the fastmap can schedule another write if bitflips are detected. Signed-off-by: Richard Weinberger --- drivers/mtd/ubi/ubi.h | 4 +++- drivers/mtd/ubi/wl.c | 8 +++++++- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h index f80ffab..04c4c05 100644 --- a/drivers/mtd/ubi/ubi.h +++ b/drivers/mtd/ubi/ubi.h @@ -427,6 +427,7 @@ struct ubi_debug_info { * @fm_size: fastmap size in bytes * @fm_sem: allows ubi_update_fastmap() to block EBA table changes * @fm_work: fastmap work queue + * @fm_work_scheduled: non-zero if fastmap work was scheduled * * @used: RB-tree of used physical eraseblocks * @erroneous: RB-tree of erroneous used physical eraseblocks @@ -438,7 +439,7 @@ struct ubi_debug_info { * @pq_head: protection queue head * @wl_lock: protects the @used, @free, @pq, @pq_head, @lookuptbl, @move_from, * @move_to, @move_to_put @erase_pending, @wl_scheduled, @works, - * @erroneous, and @erroneous_peb_count fields + * @erroneous, @erroneous_peb_count, and @fm_work_scheduled fields * @move_mutex: serializes eraseblock moves * @work_sem: used to wait for all the scheduled works to finish and prevent * new works from being submitted @@ -533,6 +534,7 @@ struct ubi_device { void *fm_buf; size_t fm_size; struct work_struct fm_work; + int fm_work_scheduled; /* Wear-leveling sub-system's stuff */ struct rb_root used; diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c index 834f6fe..7f135df 100644 --- a/drivers/mtd/ubi/wl.c +++ b/drivers/mtd/ubi/wl.c @@ -149,6 +149,9 @@ static void update_fastmap_work_fn(struct work_struct *wrk) { struct ubi_device *ubi = container_of(wrk, struct ubi_device, fm_work); ubi_update_fastmap(ubi); + spin_lock(&ubi->wl_lock); + ubi->fm_work_scheduled = 0; + spin_unlock(&ubi->wl_lock); } /** @@ -660,7 +663,10 @@ static struct ubi_wl_entry *get_peb_for_wl(struct ubi_device *ubi) /* We cannot update the fastmap here because this * function is called in atomic context. * Let's fail here and refill/update it as soon as possible. */ - schedule_work(&ubi->fm_work); + if (!ubi->fm_work_scheduled) { + ubi->fm_work_scheduled = 1; + schedule_work(&ubi->fm_work); + } return NULL; } else { pnum = pool->pebs[pool->used++]; -- 1.8.4.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/