From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: [PATCH 2/6] blkcg: remove blkio_group->path[] Date: Mon, 16 Apr 2012 13:57:23 -0700 Message-ID: <1334609847-12747-3-git-send-email-tj@kernel.org> References: <1334609847-12747-1-git-send-email-tj@kernel.org> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=3RnZEawBFmzcQ+FOSKPHf67CaL9fPrZIAGpK8Q5G1Vo=; b=FzaTrFpbdRmadDwYuqpRdni+vkYuAswKn+NF193guT4sdR+T40Zob2Y9X9YWcnUSaY EFt1BjUJhjfIjKthYll0hWaD7wuI4qt9OlIaDplZSA+QBnhZHkPMZGPWAQEyij1+S1q4 GfLh9hZreMxGLWHYjap3lappd9QRrCy3xeEWNwE92I8KBiHRu4zfUAocGSCeLtWHP6SD NR1GkHH7t6uRrgI85eeusWaMEgntUKu5J/60gd/vvJh9y+SyheFmVq2HguHb/4hIdU52 4tZXlJzbNUXHwMWHtd0igDMVG1sP7zML/WCXnHgZeVlJXyNdyH3bUOR8FXphqOESZQjQ JuDA== In-Reply-To: <1334609847-12747-1-git-send-email-tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org Cc: vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, ctalbott-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, rni-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Tejun Heo blkio_group->path[] stores the path of the associated cgroup and is used only for debug messages. Just format the path from blkg->cgroup when printing debug messages. Signed-off-by: Tejun Heo Cc: Vivek Goyal --- block/blk-cgroup.c | 1 - block/blk-cgroup.h | 21 +++++++++++++++++---- block/blk-throttle.c | 9 ++++++--- block/cfq-iosched.c | 21 ++++++++++++++------- 4 files changed, 37 insertions(+), 15 deletions(-) diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index b1807d4..6333702 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -114,7 +114,6 @@ static struct blkio_group *blkg_alloc(struct blkio_cgroup *blkcg, INIT_LIST_HEAD(&blkg->q_node); blkg->blkcg = blkcg; blkg->refcnt = 1; - cgroup_path(blkcg->css.cgroup, blkg->path, sizeof(blkg->path)); for (i = 0; i < BLKCG_MAX_POLS; i++) { struct blkio_policy_type *pol = blkio_policy[i]; diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h index ef6550a..c524267 100644 --- a/block/blk-cgroup.h +++ b/block/blk-cgroup.h @@ -77,8 +77,6 @@ struct blkio_group { struct list_head q_node; struct hlist_node blkcg_node; struct blkio_cgroup *blkcg; - /* Store cgroup path */ - char path[128]; /* reference count */ int refcnt; @@ -167,9 +165,24 @@ static inline struct blkio_group *pdata_to_blkg(void *pdata) return NULL; } -static inline char *blkg_path(struct blkio_group *blkg) +/** + * blkg_path - format cgroup path of blkg + * @blkg: blkg of interest + * @buf: target buffer + * @buflen: target buffer length + * + * Format the path of the cgroup of @blkg into @buf. + */ +static inline int blkg_path(struct blkio_group *blkg, char *buf, int buflen) { - return blkg->path; + int ret; + + rcu_read_lock(); + ret = cgroup_path(blkg->blkcg->css.cgroup, buf, buflen); + rcu_read_unlock(); + if (ret) + strncpy(buf, "", buflen); + return ret; } /** diff --git a/block/blk-throttle.c b/block/blk-throttle.c index e2aaf27..e9b7a47 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -155,9 +155,12 @@ static inline int throtl_tg_##name(const struct throtl_grp *tg) \ THROTL_TG_FNS(on_rr); -#define throtl_log_tg(td, tg, fmt, args...) \ - blk_add_trace_msg((td)->queue, "throtl %s " fmt, \ - blkg_path(tg_to_blkg(tg)), ##args); \ +#define throtl_log_tg(td, tg, fmt, args...) do { \ + char __pbuf[128]; \ + \ + blkg_path(tg_to_blkg(tg), __pbuf, sizeof(__pbuf)); \ + blk_add_trace_msg((td)->queue, "throtl %s " fmt, __pbuf, ##args); \ +} while (0) #define throtl_log(td, fmt, args...) \ blk_add_trace_msg((td)->queue, "throtl " fmt, ##args) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index eb07eb6..901286b 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -573,14 +573,21 @@ static inline void cfqg_put(struct cfq_group *cfqg) return blkg_put(cfqg_to_blkg(cfqg)); } -#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \ +#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) do { \ + char __pbuf[128]; \ + \ + blkg_path(cfqg_to_blkg((cfqq)->cfqg), __pbuf, sizeof(__pbuf)); \ blk_add_trace_msg((cfqd)->queue, "cfq%d%c %s " fmt, (cfqq)->pid, \ - cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ - blkg_path(cfqg_to_blkg((cfqq)->cfqg)), ##args) - -#define cfq_log_cfqg(cfqd, cfqg, fmt, args...) \ - blk_add_trace_msg((cfqd)->queue, "%s " fmt, \ - blkg_path(cfqg_to_blkg((cfqg))), ##args) \ + cfq_cfqq_sync((cfqq)) ? 'S' : 'A', \ + __pbuf, ##args); \ +} while (0) + +#define cfq_log_cfqg(cfqd, cfqg, fmt, args...) do { \ + char __pbuf[128]; \ + \ + blkg_path(cfqg_to_blkg(cfqg), __pbuf, sizeof(__pbuf)); \ + blk_add_trace_msg((cfqd)->queue, "%s " fmt, __pbuf, ##args); \ +} while (0) static inline void cfqg_stats_update_io_add(struct cfq_group *cfqg, struct cfq_group *curr_cfqg, int rw) -- 1.7.7.3