Factor out a helper to deal with a single blkcg_gq to make the code a
little bit easier to follow.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/blk-cgroup.c | 148 ++++++++++++++++++++++-----------------------
1 file changed, 74 insertions(+), 74 deletions(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index db034e35ae20..52aa0540ccaf 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -870,97 +870,97 @@ static void blkcg_fill_root_iostats(void)
}
}
-static int blkcg_print_stat(struct seq_file *sf, void *v)
+static void blkcg_print_one_stat(struct blkcg_gq *blkg, struct seq_file *s)
{
- struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
- struct blkcg_gq *blkg;
-
- if (!seq_css(sf)->parent)
- blkcg_fill_root_iostats();
- else
- cgroup_rstat_flush(blkcg->css.cgroup);
-
- rcu_read_lock();
+ struct blkg_iostat_set *bis = &blkg->iostat;
+ u64 rbytes, wbytes, rios, wios, dbytes, dios;
+ bool has_stats = false;
+ const char *dname;
+ unsigned seq;
+ char *buf;
+ size_t size = seq_get_buf(s, &buf), off = 0;
+ int i;
- hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) {
- struct blkg_iostat_set *bis = &blkg->iostat;
- const char *dname;
- char *buf;
- u64 rbytes, wbytes, rios, wios, dbytes, dios;
- size_t size = seq_get_buf(sf, &buf), off = 0;
- int i;
- bool has_stats = false;
- unsigned seq;
+ if (!blkg->online)
+ return;
- spin_lock_irq(&blkg->q->queue_lock);
+ dname = blkg_dev_name(blkg);
+ if (!dname)
+ return;
- if (!blkg->online)
- goto skip;
+ /*
+ * Hooray string manipulation, count is the size written NOT
+ * INCLUDING THE \0, so size is now count+1 less than what we
+ * had before, but we want to start writing the next bit from
+ * the \0 so we only add count to buf.
+ */
+ off += scnprintf(buf+off, size-off, "%s ", dname);
- dname = blkg_dev_name(blkg);
- if (!dname)
- goto skip;
+ do {
+ seq = u64_stats_fetch_begin(&bis->sync);
+
+ rbytes = bis->cur.bytes[BLKG_IOSTAT_READ];
+ wbytes = bis->cur.bytes[BLKG_IOSTAT_WRITE];
+ dbytes = bis->cur.bytes[BLKG_IOSTAT_DISCARD];
+ rios = bis->cur.ios[BLKG_IOSTAT_READ];
+ wios = bis->cur.ios[BLKG_IOSTAT_WRITE];
+ dios = bis->cur.ios[BLKG_IOSTAT_DISCARD];
+ } while (u64_stats_fetch_retry(&bis->sync, seq));
+
+ if (rbytes || wbytes || rios || wios) {
+ has_stats = true;
+ off += scnprintf(buf+off, size-off,
+ "rbytes=%llu wbytes=%llu rios=%llu wios=%llu dbytes=%llu dios=%llu",
+ rbytes, wbytes, rios, wios,
+ dbytes, dios);
+ }
- /*
- * Hooray string manipulation, count is the size written NOT
- * INCLUDING THE \0, so size is now count+1 less than what we
- * had before, but we want to start writing the next bit from
- * the \0 so we only add count to buf.
- */
- off += scnprintf(buf+off, size-off, "%s ", dname);
+ if (blkcg_debug_stats && atomic_read(&blkg->use_delay)) {
+ has_stats = true;
+ off += scnprintf(buf+off, size-off, " use_delay=%d delay_nsec=%llu",
+ atomic_read(&blkg->use_delay),
+ atomic64_read(&blkg->delay_nsec));
+ }
- do {
- seq = u64_stats_fetch_begin(&bis->sync);
+ for (i = 0; i < BLKCG_MAX_POLS; i++) {
+ struct blkcg_policy *pol = blkcg_policy[i];
+ size_t written;
- rbytes = bis->cur.bytes[BLKG_IOSTAT_READ];
- wbytes = bis->cur.bytes[BLKG_IOSTAT_WRITE];
- dbytes = bis->cur.bytes[BLKG_IOSTAT_DISCARD];
- rios = bis->cur.ios[BLKG_IOSTAT_READ];
- wios = bis->cur.ios[BLKG_IOSTAT_WRITE];
- dios = bis->cur.ios[BLKG_IOSTAT_DISCARD];
- } while (u64_stats_fetch_retry(&bis->sync, seq));
+ if (!blkg->pd[i] || !pol->pd_stat_fn)
+ continue;
- if (rbytes || wbytes || rios || wios) {
+ written = pol->pd_stat_fn(blkg->pd[i], buf+off, size-off);
+ if (written)
has_stats = true;
- off += scnprintf(buf+off, size-off,
- "rbytes=%llu wbytes=%llu rios=%llu wios=%llu dbytes=%llu dios=%llu",
- rbytes, wbytes, rios, wios,
- dbytes, dios);
- }
+ off += written;
+ }
- if (blkcg_debug_stats && atomic_read(&blkg->use_delay)) {
- has_stats = true;
- off += scnprintf(buf+off, size-off,
- " use_delay=%d delay_nsec=%llu",
- atomic_read(&blkg->use_delay),
- (unsigned long long)atomic64_read(&blkg->delay_nsec));
+ if (has_stats) {
+ if (off < size - 1) {
+ off += scnprintf(buf+off, size-off, "\n");
+ seq_commit(s, off);
+ } else {
+ seq_commit(s, -1);
}
+ }
+}
- for (i = 0; i < BLKCG_MAX_POLS; i++) {
- struct blkcg_policy *pol = blkcg_policy[i];
- size_t written;
-
- if (!blkg->pd[i] || !pol->pd_stat_fn)
- continue;
+static int blkcg_print_stat(struct seq_file *sf, void *v)
+{
+ struct blkcg *blkcg = css_to_blkcg(seq_css(sf));
+ struct blkcg_gq *blkg;
- written = pol->pd_stat_fn(blkg->pd[i], buf+off, size-off);
- if (written)
- has_stats = true;
- off += written;
- }
+ if (!seq_css(sf)->parent)
+ blkcg_fill_root_iostats();
+ else
+ cgroup_rstat_flush(blkcg->css.cgroup);
- if (has_stats) {
- if (off < size - 1) {
- off += scnprintf(buf+off, size-off, "\n");
- seq_commit(sf, off);
- } else {
- seq_commit(sf, -1);
- }
- }
- skip:
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) {
+ spin_lock_irq(&blkg->q->queue_lock);
+ blkcg_print_one_stat(blkg, sf);
spin_unlock_irq(&blkg->q->queue_lock);
}
-
rcu_read_unlock();
return 0;
}
--
2.30.2
