Re: [Cluster-devel] [GFS2 PATCH] GFS2: Log the reason for log flushes in every log header

[Steven Whitehouse]

Hi,

On 01/12/17 19:34, Bob Peterson wrote:
Hi,

This patch just adds the capability for GFS2 to track which function
called gfs2_log_flush. This should make it easier to diagnose
problems based on the sequence of events found in the journals.

Signed-off-by: Bob Peterson <rpete...@redhat.com>
---
  fs/gfs2/aops.c       |  2 +-
  fs/gfs2/file.c       |  3 ++-
  fs/gfs2/glops.c      | 13 +++++++------
  fs/gfs2/incore.h     | 22 ++++++++++++++++++++++
  fs/gfs2/log.c        | 19 +++++++++++--------
  fs/gfs2/log.h        |  3 ++-
  fs/gfs2/ops_fstype.c |  2 +-
  fs/gfs2/quota.c      |  3 ++-
  fs/gfs2/rgrp.c       |  3 ++-
  fs/gfs2/super.c      |  9 +++++----
  fs/gfs2/trans.c      |  2 +-
  11 files changed, 56 insertions(+), 25 deletions(-)

diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 658ca027cab9..10fa52321a73 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -445,7 +445,7 @@ static int gfs2_jdata_writepages(struct address_space 
*mapping,
  
  	ret = gfs2_write_cache_jdata(mapping, wbc);
        if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) {
-               gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
+               gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH, LGF_JDATA_WPAGES);
                ret = gfs2_write_cache_jdata(mapping, wbc);
        }
        return ret;
Since we already have a flags field for gfs2_log_flush, lets make these 
the same field to avoid having to send two sets of flags.

diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 58705ef8643a..e180df15e107 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -246,7 +246,8 @@ static int do_gfs2_set_flags(struct file *filp, u32 
reqflags, u32 mask)
        }
        if ((flags ^ new_flags) & GFS2_DIF_JDATA) {
                if (new_flags & GFS2_DIF_JDATA)
-                       gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
+                       gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH,
+                                      LGF_SET_FLAGS);
                error = filemap_fdatawrite(inode->i_mapping);
                if (error)
                        goto out;
diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index cdd1c5f06f45..f661fbec259c 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -107,7 +107,7 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
        __gfs2_ail_flush(gl, 0, tr.tr_revokes);
  
  	gfs2_trans_end(sdp);
-       gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
+       gfs2_log_flush(sdp, NULL, NORMAL_FLUSH, LGF_AIL_EMPTY_GL);
  }
  
  void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
@@ -128,7 +128,7 @@ void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
                return;
        __gfs2_ail_flush(gl, fsync, max_revokes);
        gfs2_trans_end(sdp);
-       gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
+       gfs2_log_flush(sdp, NULL, NORMAL_FLUSH, LGF_AIL_FLUSH);
  }
  
  /**
@@ -157,7 +157,7 @@ static void rgrp_go_sync(struct gfs2_glock *gl)
                return;
        GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
  
-	gfs2_log_flush(sdp, gl, NORMAL_FLUSH);
+       gfs2_log_flush(sdp, gl, NORMAL_FLUSH, LGF_RGRP_GO_SYNC);
        filemap_fdatawrite_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
        error = filemap_fdatawait_range(mapping, gl->gl_vm.start, 
gl->gl_vm.end);
        mapping_set_error(mapping, error);
@@ -252,7 +252,7 @@ static void inode_go_sync(struct gfs2_glock *gl)
  
  	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
  
-	gfs2_log_flush(gl->gl_name.ln_sbd, gl, NORMAL_FLUSH);
+       gfs2_log_flush(gl->gl_name.ln_sbd, gl, NORMAL_FLUSH, LGF_INODE_GO_SYNC);
        filemap_fdatawrite(metamapping);
        if (isreg) {
                struct address_space *mapping = ip->i_inode.i_mapping;
@@ -303,7 +303,8 @@ static void inode_go_inval(struct gfs2_glock *gl, int flags)
        }
  
  	if (ip == GFS2_I(gl->gl_name.ln_sbd->sd_rindex)) {
-               gfs2_log_flush(gl->gl_name.ln_sbd, NULL, NORMAL_FLUSH);
+               gfs2_log_flush(gl->gl_name.ln_sbd, NULL, NORMAL_FLUSH,
+                              LGF_INODE_GO_INVAL);
                gl->gl_name.ln_sbd->sd_rindex_uptodate = 0;
        }
        if (ip && S_ISREG(ip->i_inode.i_mode))
@@ -495,7 +496,7 @@ static void freeze_go_sync(struct gfs2_glock *gl)
                        gfs2_assert_withdraw(sdp, 0);
                }
                queue_work(gfs2_freeze_wq, &sdp->sd_freeze_work);
-               gfs2_log_flush(sdp, NULL, FREEZE_FLUSH);
+               gfs2_log_flush(sdp, NULL, FREEZE_FLUSH, LGF_FREEZE_GO_SYNC);
        }
  }
  
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 6e18e9793ec4..1e07fa2468f9 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -134,6 +134,28 @@ enum gfs2_state_bits {
        BH_Zeronew = BH_PrivateStart + 2,
  };
  
+enum gfs2_log_flushers {
+       LGF_SHUTDOWN            = 0x701,
+       LGF_JDATA_WPAGES        = 0x702,
+       LGF_SET_FLAGS           = 0x703,
+       LGF_AIL_EMPTY_GL        = 0x704,
+       LGF_AIL_FLUSH           = 0x705,
+       LGF_RGRP_GO_SYNC        = 0x706,
+       LGF_INODE_GO_SYNC       = 0x707,
+       LGF_INODE_GO_INVAL      = 0x708,
+       LGF_FREEZE_GO_SYNC      = 0x709,
+       LGF_KILL_SB             = 0x70a,
+       LGF_DO_SYNC             = 0x70b,
+       LGF_INPLACE_RESERVE     = 0x70c,
+       LGF_WRITE_INODE         = 0x70d,
+       LGF_MAKE_FS_RO          = 0x70e,
+       LGF_SYNC_FS             = 0x70f,
+       LGF_EVICT_INODE         = 0x710,
+       LGF_TRANS_END           = 0x711,
+       LGF_LOGD_JFLUSH_REQD    = 0x712,
+       LGF_LOGD_AIL_FLUSH_REQD = 0x712,
+};
+
These constants are written to disk, so they need to be in the ondisk 
header file in order that the utils can access them.

Steve.