GFS2: Improve tracing support (adds two flags)
This adds support for two new flags. One keeps track of whether
the glock is on the LRU list or not. The other isn't really a
flag as such, but an indication of whether the glock has an
attached object or not. This indication is reported without
any locking, which is ok since we do not dereference the object
pointer but merely report whether it is NULL or not.
Also, this fixes one place where a tracepoint was missing, which
was at the point we remove deallocated blocks from the journal.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 1019183..0c6c690 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -170,6 +170,7 @@
atomic_inc(&lru_count);
list_add_tail(&gl->gl_lru, &lru_list);
+ set_bit(GLF_LRU, &gl->gl_flags);
spin_unlock(&lru_lock);
}
@@ -1364,6 +1365,7 @@
while(nr && !list_empty(&lru_list)) {
gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
list_del_init(&gl->gl_lru);
+ clear_bit(GLF_LRU, &gl->gl_flags);
atomic_dec(&lru_count);
/* Test for being demotable */
@@ -1386,6 +1388,7 @@
}
nr_skipped++;
list_add(&gl->gl_lru, &skipped);
+ set_bit(GLF_LRU, &gl->gl_flags);
}
list_splice(&skipped, &lru_list);
atomic_add(nr_skipped, &lru_count);
@@ -1598,9 +1601,11 @@
return 0;
}
-static const char *gflags2str(char *buf, const unsigned long *gflags)
+static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
{
+ const unsigned long *gflags = &gl->gl_flags;
char *p = buf;
+
if (test_bit(GLF_LOCK, gflags))
*p++ = 'l';
if (test_bit(GLF_DEMOTE, gflags))
@@ -1623,6 +1628,10 @@
*p++ = 'F';
if (test_bit(GLF_QUEUED, gflags))
*p++ = 'q';
+ if (test_bit(GLF_LRU, gflags))
+ *p++ = 'L';
+ if (gl->gl_object)
+ *p++ = 'o';
*p = 0;
return buf;
}
@@ -1661,7 +1670,7 @@
state2str(gl->gl_state),
gl->gl_name.ln_type,
(unsigned long long)gl->gl_name.ln_number,
- gflags2str(gflags_buf, &gl->gl_flags),
+ gflags2str(gflags_buf, gl),
state2str(gl->gl_target),
state2str(gl->gl_demote_state), dtime,
atomic_read(&gl->gl_ail_count),
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 870a89d..48eb1ee 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -200,6 +200,8 @@
GLF_INITIAL = 10,
GLF_FROZEN = 11,
GLF_QUEUED = 12,
+ GLF_LRU = 13,
+ GLF_OBJECT = 14, /* Used only for tracing */
};
struct gfs2_glock {
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 675349b..747238c 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -31,6 +31,7 @@
#include "rgrp.h"
#include "trans.h"
#include "util.h"
+#include "trace_gfs2.h"
static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc)
{
@@ -310,6 +311,7 @@
struct gfs2_bufdata *bd = bh->b_private;
if (test_clear_buffer_pinned(bh)) {
+ trace_gfs2_pin(bd, 0);
atomic_dec(&sdp->sd_log_pinned);
list_del_init(&bd->bd_le.le_list);
if (meta) {
diff --git a/fs/gfs2/trace_gfs2.h b/fs/gfs2/trace_gfs2.h
index cedb0bb..9133d0a 100644
--- a/fs/gfs2/trace_gfs2.h
+++ b/fs/gfs2/trace_gfs2.h
@@ -40,7 +40,9 @@
{(1UL << GLF_REPLY_PENDING), "r" }, \
{(1UL << GLF_INITIAL), "I" }, \
{(1UL << GLF_FROZEN), "F" }, \
- {(1UL << GLF_QUEUED), "q" })
+ {(1UL << GLF_QUEUED), "q" }, \
+ {(1UL << GLF_LRU), "L" }, \
+ {(1UL << GLF_OBJECT), "o" })
#ifndef NUMPTY
#define NUMPTY
@@ -94,7 +96,7 @@
__entry->new_state = glock_trace_state(new_state);
__entry->tgt_state = glock_trace_state(gl->gl_target);
__entry->dmt_state = glock_trace_state(gl->gl_demote_state);
- __entry->flags = gl->gl_flags;
+ __entry->flags = gl->gl_flags | (gl->gl_object ? (1UL<<GLF_OBJECT) : 0);
),
TP_printk("%u,%u glock %d:%lld state %s to %s tgt:%s dmt:%s flags:%s",
@@ -127,7 +129,7 @@
__entry->gltype = gl->gl_name.ln_type;
__entry->glnum = gl->gl_name.ln_number;
__entry->cur_state = glock_trace_state(gl->gl_state);
- __entry->flags = gl->gl_flags;
+ __entry->flags = gl->gl_flags | (gl->gl_object ? (1UL<<GLF_OBJECT) : 0);
),
TP_printk("%u,%u glock %d:%lld state %s => %s flags:%s",
@@ -161,7 +163,7 @@
__entry->glnum = gl->gl_name.ln_number;
__entry->cur_state = glock_trace_state(gl->gl_state);
__entry->dmt_state = glock_trace_state(gl->gl_demote_state);
- __entry->flags = gl->gl_flags;
+ __entry->flags = gl->gl_flags | (gl->gl_object ? (1UL<<GLF_OBJECT) : 0);
),
TP_printk("%u,%u glock %d:%lld demote %s to %s flags:%s",