LU-2800 autoconf: remove LC_PROCFS_USERS test

In-procfs locking has been upstream since v2.6.23

We can remove the test and the dead code (lots of it). Further
review should be made to determine whether _lprocfs_lock is
still necessary at all.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: James Simmons <uja.ornl@gmail.com>
Change-Id: I6384a9776fcb45de74d10beee8c1b8477b1ffad6
Reviewed-on: http://review.whamcloud.com/5353
Reviewed-by: Bob Glossman <bob.glossman@intel.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/libcfs/include/libcfs/params_tree.h b/libcfs/include/libcfs/params_tree.h
index 1bf8d37..41413eb 100644 (file)
--- a/libcfs/include/libcfs/params_tree.h
+++ b/libcfs/include/libcfs/params_tree.h
@@ -78,46 +78,8 @@ typedef struct poll_table_struct                cfs_poll_table_t;
 /* in lprocfs_stat.c, to protect the private data for proc entries */
 extern struct rw_semaphore             _lprocfs_lock;
 
-/* to begin from 2.6.23, Linux defines self file_operations (proc_reg_file_ops)
- * in procfs, the proc file_operation defined by Lustre (lprocfs_generic_fops)
- * will be wrapped into the new defined proc_reg_file_ops, which instroduces
- * user count in proc_dir_entrey(pde_users) to protect the proc entry from
- * being deleted. then the protection lock (_lprocfs_lock) defined by Lustre
- * isn't necessary anymore for lprocfs_generic_fops(e.g. lprocfs_fops_read).
- * see bug19706 for detailed information.
- */
-#ifndef HAVE_PROCFS_USERS
-
-#define LPROCFS_ENTRY()                \
-do {                                   \
-       down_read(&_lprocfs_lock);      \
-} while(0)
-
-#define LPROCFS_EXIT()                 \
-do {                                   \
-       up_read(&_lprocfs_lock);        \
-} while(0)
-
-#else
-#define LPROCFS_ENTRY() do{ }while(0)
-#define LPROCFS_EXIT()  do{ }while(0)
-#endif
-
-#ifdef HAVE_PROCFS_DELETED
-
-static inline
-int LPROCFS_ENTRY_AND_CHECK(struct proc_dir_entry *dp)
-{
-        LPROCFS_ENTRY();
-        if ((dp)->deleted) {
-                LPROCFS_EXIT();
-                return -ENODEV;
-        }
-        return 0;
-}
-#elif defined(HAVE_PROCFS_USERS) /* !HAVE_PROCFS_DELETED*/
 static inline
-int LPROCFS_ENTRY_AND_CHECK(struct proc_dir_entry *dp)
+int LPROCFS_ENTRY_CHECK(struct proc_dir_entry *dp)
 {
        int deleted = 0;
 
@@ -129,14 +91,6 @@ int LPROCFS_ENTRY_AND_CHECK(struct proc_dir_entry *dp)
                return -ENODEV;
        return 0;
 }
-#else /* !HAVE_PROCFS_DELETED*/
-static inline
-int LPROCFS_ENTRY_AND_CHECK(struct proc_dir_entry *dp)
-{
-        LPROCFS_ENTRY();
-        return 0;
-}
-#endif /* HAVE_PROCFS_DELETED */
 #define LPROCFS_SRCH_ENTRY()            \
 do {                                    \
         down_read(&_lprocfs_lock);      \
@@ -247,12 +201,9 @@ do {                                                    \
         rc = 0;                                         \
 } while(0)
 
-#define LPROCFS_ENTRY()             do {} while(0)
-#define LPROCFS_EXIT()              do {} while(0)
 static inline
-int LPROCFS_ENTRY_AND_CHECK(cfs_param_dentry_t *dp)
+int LPROCFS_ENTRY_CHECK(cfs_param_dentry_t *dp)
 {
-        LPROCFS_ENTRY();
         return 0;
 }
 #define LPROCFS_WRITE_ENTRY()       do {} while(0)

diff --git a/lustre/autoconf/lustre-core.m4 b/lustre/autoconf/lustre-core.m4
index ec50de0..cd6fd43 100644 (file)
--- a/lustre/autoconf/lustre-core.m4
+++ b/lustre/autoconf/lustre-core.m4
@@ -461,36 +461,6 @@ LB_LINUX_TRY_COMPILE([
 ])
 ])
 
-# 2.6.23 add code to wait other users to complete before removing procfs entry
-AC_DEFUN([LC_PROCFS_USERS],
-[AC_MSG_CHECKING([if kernel has pde_users member in procfs entry struct])
-LB_LINUX_TRY_COMPILE([
-        #include <linux/proc_fs.h>
-],[
-        struct proc_dir_entry pde;
-
-        pde.pde_users   = 0;
-],[
-        AC_MSG_RESULT([yes])
-        AC_DEFINE(HAVE_PROCFS_USERS, 1,
-                [kernel has pde_users member in procfs entry struct])
-],[
-       LB_LINUX_TRY_COMPILE([
-               #include "$LINUX/fs/proc/internal.h"
-       ],[
-               struct proc_dir_entry_aux pde_aux;
-
-               pde_aux.pde_users = 0;
-       ],[
-               AC_MSG_RESULT([yes])
-               AC_DEFINE(HAVE_PROCFS_USERS, 1,
-                       [kernel has pde_users member in proc_dir_entry_aux])
-       ],[
-               AC_MSG_RESULT([no])
-       ])
-])
-])
-
 # 2.6.24
 
 # 2.6.24 has bio_endio with 2 args
@@ -509,24 +479,6 @@ LB_LINUX_TRY_COMPILE([
 ])
 ])
 
-# 2.6.24 removes long aged procfs entry -> deleted member
-AC_DEFUN([LC_PROCFS_DELETED],
-[AC_MSG_CHECKING([if kernel has deleted member in procfs entry struct])
-LB_LINUX_TRY_COMPILE([
-       #include <linux/proc_fs.h>
-],[
-        struct proc_dir_entry pde;
-
-        pde.deleted = sizeof(pde);
-], [
-        AC_MSG_RESULT([yes])
-        AC_DEFINE(HAVE_PROCFS_DELETED, 1,
-                [kernel has deleted member in procfs entry struct])
-],[
-        AC_MSG_RESULT([no])
-])
-])
-
 # 2.6.26
 
 # 2.6.26 isn't export set_fs_pwd and change paramter in fs struct
@@ -1564,11 +1516,9 @@ AC_DEFUN([LC_PROG_LINUX],
 
          # 2.6.23
          LC_UNREGISTER_BLKDEV_RETURN_INT
-         LC_PROCFS_USERS
 
          # 2.6.24
          LC_BIO_ENDIO_2ARG
-         LC_PROCFS_DELETED
 
          # 2.6.26
          LC_FS_STRUCT_USE_PATH

diff --git a/lustre/fld/lproc_fld.c b/lustre/fld/lproc_fld.c
index 97bd3d5..c3734c7 100644 (file)
--- a/lustre/fld/lproc_fld.c
+++ b/lustre/fld/lproc_fld.c
@@ -282,7 +282,7 @@ static int fldb_seq_open(struct inode *inode, struct file *file)
        int                     env_init = 0;
        int                     rc;
 
-       LPROCFS_ENTRY_AND_CHECK(dp);
+       LPROCFS_ENTRY_CHECK(dp);
        rc = seq_open(file, &fldb_sops);
        if (rc)
                GOTO(out, rc);
@@ -319,7 +319,6 @@ out:
                        lu_env_fini(&param->fsp_env);
                if (param != NULL)
                        OBD_FREE_PTR(param);
-               LPROCFS_EXIT();
        }
        return rc;
 }

diff --git a/lustre/include/lprocfs_status.h b/lustre/include/lprocfs_status.h
index ff60773..9142ac9 100644 (file)
--- a/lustre/include/lprocfs_status.h
+++ b/lustre/include/lprocfs_status.h
@@ -750,14 +750,8 @@ extern int lprocfs_seq_release(cfs_inode_t *, struct file *);
 #define __LPROC_SEQ_FOPS(name, custom_seq_write)                           \
 static int name##_single_open(cfs_inode_t *inode, struct file *file) {     \
         struct proc_dir_entry *dp = PDE(inode);                            \
-        int rc;                                                            \
-        LPROCFS_ENTRY_AND_CHECK(dp);                                       \
-        rc = single_open(file, name##_seq_show, dp->data);                 \
-        if (rc) {                                                          \
-                LPROCFS_EXIT();                                            \
-                return rc;                                                 \
-        }                                                                  \
-        return 0;                                                          \
+       LPROCFS_ENTRY_CHECK(dp);                                           \
+       return single_open(file, name##_seq_show, dp->data);               \
 }                                                                          \
 struct file_operations name##_fops = {                                     \
         .owner   = THIS_MODULE,                                            \

diff --git a/lustre/lod/lproc_lod.c b/lustre/lod/lproc_lod.c
index 6fe74e3..e976063 100644 (file)
--- a/lustre/lod/lproc_lod.c
+++ b/lustre/lod/lproc_lod.c
@@ -418,12 +418,10 @@ static int lod_osts_seq_open(struct inode *inode, struct file *file)
        struct seq_file *seq;
        int rc;
 
-       LPROCFS_ENTRY_AND_CHECK(dp);
+       LPROCFS_ENTRY_CHECK(dp);
        rc = seq_open(file, &lod_osts_sops);
-       if (rc) {
-               LPROCFS_EXIT();
+       if (rc)
                return rc;
-       }
 
        seq = file->private_data;
        seq->private = dp->data;

diff --git a/lustre/lov/lproc_lov.c b/lustre/lov/lproc_lov.c
index 1c5839c..850bb39 100644 (file)
--- a/lustre/lov/lproc_lov.c
+++ b/lustre/lov/lproc_lov.c
@@ -252,12 +252,10 @@ static int lov_target_seq_open(struct inode *inode, struct file *file)
         struct seq_file *seq;
         int rc;
 
-        LPROCFS_ENTRY_AND_CHECK(dp);
+       LPROCFS_ENTRY_CHECK(dp);
         rc = seq_open(file, &lov_tgt_sops);
-        if (rc) {
-                LPROCFS_EXIT();
+       if (rc)
                 return rc;
-        }
 
         seq = file->private_data;
         seq->private = dp->data;

diff --git a/lustre/mdt/mdt_hsm_cdt_actions.c b/lustre/mdt/mdt_hsm_cdt_actions.c
index 37a4da1..ea2187a 100644 (file)
--- a/lustre/mdt/mdt_hsm_cdt_actions.c
+++ b/lustre/mdt/mdt_hsm_cdt_actions.c
@@ -541,14 +541,12 @@ static int lprocfs_open_agent_actions(struct inode *inode, struct file *file)
        struct mdt_device               *mdt;
        ENTRY;
 
-       if (LPROCFS_ENTRY_AND_CHECK(PDE(inode)))
+       if (LPROCFS_ENTRY_CHECK(PDE(inode)))
                RETURN(-ENOENT);
 
        rc = seq_open(file, &mdt_agent_actions_proc_ops);
-       if (rc) {
-               LPROCFS_EXIT();
+       if (rc)
                RETURN(rc);
-       }
 
        OBD_ALLOC_PTR(aai);
        if (aai == NULL)

diff --git a/lustre/obdclass/lprocfs_jobstats.c b/lustre/obdclass/lprocfs_jobstats.c
index dab281b..f67e426 100644 (file)
--- a/lustre/obdclass/lprocfs_jobstats.c
+++ b/lustre/obdclass/lprocfs_jobstats.c
@@ -420,14 +420,12 @@ static int lprocfs_jobstats_seq_open(struct inode *inode, struct file *file)
        struct seq_file *seq;
        int rc;
 
-       if (LPROCFS_ENTRY_AND_CHECK(dp))
+       if (LPROCFS_ENTRY_CHECK(dp))
                return -ENOENT;
 
        rc = seq_open(file, &lprocfs_jobstats_seq_sops);
-       if (rc) {
-               LPROCFS_EXIT();
+       if (rc)
                return rc;
-       }
        seq = file->private_data;
        seq->private = dp->data;
        return 0;

diff --git a/lustre/obdclass/lprocfs_status.c b/lustre/obdclass/lprocfs_status.c
index 8b52d52..6544034 100644 (file)
--- a/lustre/obdclass/lprocfs_status.c
+++ b/lustre/obdclass/lprocfs_status.c
@@ -62,14 +62,12 @@ EXPORT_SYMBOL(_lprocfs_lock);
 
 int lprocfs_single_release(struct inode *inode, struct file *file)
 {
-        LPROCFS_EXIT();
         return single_release(inode, file);
 }
 EXPORT_SYMBOL(lprocfs_single_release);
 
 int lprocfs_seq_release(struct inode *inode, struct file *file)
 {
-        LPROCFS_EXIT();
         return seq_release(inode, file);
 }
 EXPORT_SYMBOL(lprocfs_seq_release);
@@ -205,7 +203,7 @@ static ssize_t lprocfs_fops_read(struct file *f, char __user *buf,
         if (page == NULL)
                 return -ENOMEM;
 
-        if (LPROCFS_ENTRY_AND_CHECK(dp)) {
+       if (LPROCFS_ENTRY_CHECK(dp)) {
                 rc = -ENOENT;
                 goto out;
         }
@@ -214,7 +212,6 @@ static ssize_t lprocfs_fops_read(struct file *f, char __user *buf,
         if (dp->read_proc)
                rc = dp->read_proc(page, &start, *ppos, PAGE_CACHE_SIZE,
                                    &eof, dp->data);
-        LPROCFS_EXIT();
         if (rc <= 0)
                 goto out;
 
@@ -250,11 +247,10 @@ static ssize_t lprocfs_fops_write(struct file *f, const char __user *buf,
         struct proc_dir_entry *dp = PDE(f->f_dentry->d_inode);
         int rc = -EIO;
 
-        if (LPROCFS_ENTRY_AND_CHECK(dp))
+       if (LPROCFS_ENTRY_CHECK(dp))
                 return -ENOENT;
         if (dp->write_proc)
                 rc = dp->write_proc(f, buf, size, dp->data);
-        LPROCFS_EXIT();
         return rc;
 }
 
@@ -1472,14 +1468,12 @@ static int lprocfs_stats_seq_open(struct inode *inode, struct file *file)
         struct seq_file *seq;
         int rc;
 
-        if (LPROCFS_ENTRY_AND_CHECK(dp))
+       if (LPROCFS_ENTRY_CHECK(dp))
                 return -ENOENT;
 
         rc = seq_open(file, &lprocfs_stats_seq_sops);
-        if (rc) {
-                LPROCFS_EXIT();
+       if (rc)
                 return rc;
-        }
         seq = file->private_data;
         seq->private = dp->data;
         return 0;

diff --git a/lustre/ptlrpc/lproc_ptlrpc.c b/lustre/ptlrpc/lproc_ptlrpc.c
index 47ed364..e2ba1ee 100644 (file)
--- a/lustre/ptlrpc/lproc_ptlrpc.c
+++ b/lustre/ptlrpc/lproc_ptlrpc.c
@@ -992,12 +992,10 @@ ptlrpc_lprocfs_svc_req_history_open(struct inode *inode, struct file *file)
         struct seq_file       *seqf;
         int                    rc;
 
-        LPROCFS_ENTRY_AND_CHECK(dp);
+       LPROCFS_ENTRY_CHECK(dp);
         rc = seq_open(file, &sops);
-        if (rc) {
-                LPROCFS_EXIT();
+       if (rc)
                 return rc;
-        }
 
         seqf = file->private_data;
         seqf->private = dp->data;
@@ -1242,14 +1240,6 @@ int lprocfs_wr_evict_client(struct file *file, const char *buffer,
                 goto out;
         }
         tmpbuf = cfs_firststr(kbuf, min_t(unsigned long, BUFLEN - 1, count));
-        /* Kludge code(deadlock situation): the lprocfs lock has been held
-         * since the client is evicted by writting client's
-         * uuid/nid to procfs "evict_client" entry. However,
-         * obd_export_evict_by_uuid() will call lprocfs_remove() to destroy
-         * the proc entries under the being destroyed export{}, so I have
-         * to drop the lock at first here.
-         * - jay, jxiong@clusterfs.com */
-        LPROCFS_EXIT();
        class_incref(obd, __FUNCTION__, cfs_current());
 
         if (strncmp(tmpbuf, "nid:", 4) == 0)
@@ -1260,7 +1250,6 @@ int lprocfs_wr_evict_client(struct file *file, const char *buffer,
                 obd_export_evict_by_uuid(obd, tmpbuf);
 
        class_decref(obd, __FUNCTION__, cfs_current());
-        LPROCFS_ENTRY();
 
 out:
         OBD_FREE(kbuf, BUFLEN);

diff --git a/lustre/quota/lproc_quota.c b/lustre/quota/lproc_quota.c
index 38f3bb2..791f47d 100644 (file)
--- a/lustre/quota/lproc_quota.c
+++ b/lustre/quota/lproc_quota.c
@@ -280,21 +280,19 @@ static int lprocfs_quota_seq_open(struct inode *inode, struct file *file)
                goto out_lqp;
        }
 
-       if (LPROCFS_ENTRY_AND_CHECK(dp)) {
+       if (LPROCFS_ENTRY_CHECK(dp)) {
                rc = -ENOENT;
                goto out_env;
        }
 
        rc = seq_open(file, &lprocfs_quota_seq_sops);
        if (rc)
-               goto out_lprocfs;
+               goto out_env;
 
        seq = file->private_data;
        seq->private = lqp;
        return 0;
 
-out_lprocfs:
-       LPROCFS_EXIT();
 out_env:
        lu_env_fini(&lqp->lqp_env);
 out_lqp:
@@ -307,8 +305,6 @@ static int lprocfs_quota_seq_release(struct inode *inode, struct file *file)
        struct seq_file         *seq = file->private_data;
        struct lquota_procfs    *lqp = seq->private;
 
-       LPROCFS_EXIT();
-
        LASSERT(lqp);
        lu_env_fini(&lqp->lqp_env);
        OBD_FREE_PTR(lqp);