staging/lustre/llite: define per open file cache for ll_cl_context

In ll_readpage and ll_write_begin, it needs to find out the cl_env
and cl_io, a.k.a ll_cl_context, when the IO is initialized. It used
to call cl_env_get() to figure it out but turned out to be contended
if multiple threads are doing IO.

In this patch, a per open file ll_cl_context cache is created. When
IO type of CIT_READ, CIT_WRITE and CIR_FAULT is initialized, it will
add a ll_cl_context into the cache maintained in ll_file_data. In this
case, the ll_cl_context can be found in ll_readpage and ll_write_begin
later.

Signed-off-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-on: http://review.whamcloud.com/10503
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5108
Reviewed-on: http://review.whamcloud.com/10955
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5260
Reviewed-by: Lai Siyao <lai.siyao@intel.com>
Reviewed-by: Bobi Jam <bobijam@gmail.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lustre/llite/file.c b/drivers/staging/lustre/lustre/llite/file.c
index 0191945..bafa0b7 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/file.c
+++ b/drivers/staging/lustre/lustre/llite/file.c
@@ -519,6 +519,11 @@ static int ll_local_open(struct file *file, struct lookup_intent *it,
        LUSTRE_FPRIVATE(file) = fd;
        ll_readahead_init(inode, &fd->fd_ras);
        fd->fd_omode = it->it_flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
+
+       /* ll_cl_context initialize */
+       rwlock_init(&fd->fd_lock);
+       INIT_LIST_HEAD(&fd->fd_lccs);
+
        return 0;
 }
 
@@ -1178,7 +1183,9 @@ restart:
                        CERROR("Unknown IO type - %u\n", vio->vui_io_subtype);
                        LBUG();
                }
+               ll_cl_add(file, env, io);
                result = cl_io_loop(env, io);
+               ll_cl_remove(file, env);
                if (args->via_io_subtype == IO_NORMAL)
                        up_read(&lli->lli_trunc_sem);
                if (write_mutex_locked)

diff --git a/drivers/staging/lustre/lustre/llite/llite_internal.h b/drivers/staging/lustre/lustre/llite/llite_internal.h
index 3f2f30b..7fb949a 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/llite_internal.h
+++ b/drivers/staging/lustre/lustre/llite/llite_internal.h
@@ -640,6 +640,8 @@ struct ll_file_data {
         * false: unknown failure, should report.
         */
        bool fd_write_failed;
+       rwlock_t fd_lock; /* protect lcc list */
+       struct list_head fd_lccs; /* list of ll_cl_context */
 };
 
 struct lov_stripe_md;
@@ -715,8 +717,9 @@ void ll_readahead_init(struct inode *inode, struct ll_readahead_state *ras);
 int ll_readahead(const struct lu_env *env, struct cl_io *io,
                 struct cl_page_list *queue, struct ll_readahead_state *ras,
                 bool hit);
-struct ll_cl_context *ll_cl_init(struct file *file, struct page *vmpage);
-void ll_cl_fini(struct ll_cl_context *lcc);
+struct ll_cl_context *ll_cl_find(struct file *file);
+void ll_cl_add(struct file *file, const struct lu_env *env, struct cl_io *io);
+void ll_cl_remove(struct file *file, const struct lu_env *env);
 
 extern const struct address_space_operations ll_aops;
 
@@ -858,11 +861,11 @@ struct vvp_io_args {
 };
 
 struct ll_cl_context {
+       struct list_head         lcc_list;
        void       *lcc_cookie;
+       const struct lu_env     *lcc_env;
        struct cl_io   *lcc_io;
        struct cl_page *lcc_page;
-       struct lu_env  *lcc_env;
-       int          lcc_refcheck;
 };
 
 struct ll_thread_info {

diff --git a/drivers/staging/lustre/lustre/llite/llite_mmap.c b/drivers/staging/lustre/lustre/llite/llite_mmap.c
index 88ef1ca..7610799 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/llite_mmap.c
+++ b/drivers/staging/lustre/lustre/llite/llite_mmap.c
@@ -315,8 +315,13 @@ static int ll_fault0(struct vm_area_struct *vma, struct vm_fault *vmf)
                vio->u.fault.ft_flags = 0;
                vio->u.fault.ft_flags_valid = false;
 
+               /* May call ll_readpage() */
+               ll_cl_add(vma->vm_file, env, io);
+
                result = cl_io_loop(env, io);
 
+               ll_cl_remove(vma->vm_file, env);
+
                /* ft_flags are only valid if we reached
                 * the call to filemap_fault
                 */

diff --git a/drivers/staging/lustre/lustre/llite/rw.c b/drivers/staging/lustre/lustre/llite/rw.c
index 3363977..fa42869 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/rw.c
+++ b/drivers/staging/lustre/lustre/llite/rw.c
@@ -59,84 +59,6 @@
 #include "llite_internal.h"
 #include "../include/linux/lustre_compat25.h"
 
-/**
- * Finalizes cl-data before exiting typical address_space operation. Dual to
- * ll_cl_init().
- */
-void ll_cl_fini(struct ll_cl_context *lcc)
-{
-       struct lu_env  *env  = lcc->lcc_env;
-       struct cl_io   *io   = lcc->lcc_io;
-       struct cl_page *page = lcc->lcc_page;
-
-       LASSERT(lcc->lcc_cookie == current);
-       LASSERT(env);
-
-       if (page) {
-               lu_ref_del(&page->cp_reference, "cl_io", io);
-               cl_page_put(env, page);
-       }
-
-       cl_env_put(env, &lcc->lcc_refcheck);
-}
-
-/**
- * Initializes common cl-data at the typical address_space operation entry
- * point.
- */
-struct ll_cl_context *ll_cl_init(struct file *file, struct page *vmpage)
-{
-       struct ll_cl_context *lcc;
-       struct lu_env    *env;
-       struct cl_io     *io;
-       struct cl_object *clob;
-       struct vvp_io    *vio;
-
-       int refcheck;
-       int result = 0;
-
-       clob = ll_i2info(file_inode(file))->lli_clob;
-       LASSERT(clob);
-
-       env = cl_env_get(&refcheck);
-       if (IS_ERR(env))
-               return ERR_CAST(env);
-
-       lcc = &ll_env_info(env)->lti_io_ctx;
-       memset(lcc, 0, sizeof(*lcc));
-       lcc->lcc_env = env;
-       lcc->lcc_refcheck = refcheck;
-       lcc->lcc_cookie = current;
-
-       vio = vvp_env_io(env);
-       io = vio->vui_cl.cis_io;
-       lcc->lcc_io = io;
-       if (!io)
-               result = -EIO;
-
-       if (result == 0 && vmpage) {
-               struct cl_page   *page;
-
-               LASSERT(io->ci_state == CIS_IO_GOING);
-               LASSERT(vio->vui_fd == LUSTRE_FPRIVATE(file));
-               page = cl_page_find(env, clob, vmpage->index, vmpage,
-                                   CPT_CACHEABLE);
-               if (!IS_ERR(page)) {
-                       lcc->lcc_page = page;
-                       lu_ref_add(&page->cp_reference, "cl_io", io);
-                       result = 0;
-               } else {
-                       result = PTR_ERR(page);
-               }
-       }
-       if (result) {
-               ll_cl_fini(lcc);
-               lcc = ERR_PTR(result);
-       }
-
-       return lcc;
-}
-
 static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which);
 
 /**
@@ -1112,17 +1034,70 @@ int ll_writepages(struct address_space *mapping, struct writeback_control *wbc)
        return result;
 }
 
+struct ll_cl_context *ll_cl_find(struct file *file)
+{
+       struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
+       struct ll_cl_context *lcc;
+       struct ll_cl_context *found = NULL;
+
+       read_lock(&fd->fd_lock);
+       list_for_each_entry(lcc, &fd->fd_lccs, lcc_list) {
+               if (lcc->lcc_cookie == current) {
+                       found = lcc;
+                       break;
+               }
+       }
+       read_unlock(&fd->fd_lock);
+
+       return found;
+}
+
+void ll_cl_add(struct file *file, const struct lu_env *env, struct cl_io *io)
+{
+       struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
+       struct ll_cl_context *lcc = &ll_env_info(env)->lti_io_ctx;
+
+       memset(lcc, 0, sizeof(*lcc));
+       INIT_LIST_HEAD(&lcc->lcc_list);
+       lcc->lcc_cookie = current;
+       lcc->lcc_env = env;
+       lcc->lcc_io = io;
+
+       write_lock(&fd->fd_lock);
+       list_add(&lcc->lcc_list, &fd->fd_lccs);
+       write_unlock(&fd->fd_lock);
+}
+
+void ll_cl_remove(struct file *file, const struct lu_env *env)
+{
+       struct ll_file_data *fd = LUSTRE_FPRIVATE(file);
+       struct ll_cl_context *lcc = &ll_env_info(env)->lti_io_ctx;
+
+       write_lock(&fd->fd_lock);
+       list_del_init(&lcc->lcc_list);
+       write_unlock(&fd->fd_lock);
+}
+
 int ll_readpage(struct file *file, struct page *vmpage)
 {
+       struct cl_object *clob = ll_i2info(file_inode(file))->lli_clob;
        struct ll_cl_context *lcc;
+       const struct lu_env  *env;
+       struct cl_io   *io;
+       struct cl_page *page;
        int result;
 
-       lcc = ll_cl_init(file, vmpage);
-       if (!IS_ERR(lcc)) {
-               struct lu_env  *env  = lcc->lcc_env;
-               struct cl_io   *io   = lcc->lcc_io;
-               struct cl_page *page = lcc->lcc_page;
+       lcc = ll_cl_find(file);
+       if (!lcc) {
+               unlock_page(vmpage);
+               return -EIO;
+       }
 
+       env = lcc->lcc_env;
+       io = lcc->lcc_io;
+       LASSERT(io->ci_state == CIS_IO_GOING);
+       page = cl_page_find(env, clob, vmpage->index, vmpage, CPT_CACHEABLE);
+       if (!IS_ERR(page)) {
                LASSERT(page->cp_type == CPT_CACHEABLE);
                if (likely(!PageUptodate(vmpage))) {
                        cl_page_assume(env, io, page);
@@ -1132,10 +1107,10 @@ int ll_readpage(struct file *file, struct page *vmpage)
                        unlock_page(vmpage);
                        result = 0;
                }
-               ll_cl_fini(lcc);
+               cl_page_put(env, page);
        } else {
                unlock_page(vmpage);
-               result = PTR_ERR(lcc);
+               result = PTR_ERR(page);
        }
        return result;
 }

diff --git a/drivers/staging/lustre/lustre/llite/rw26.c b/drivers/staging/lustre/lustre/llite/rw26.c
index c12a048..947a4f5 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/rw26.c
+++ b/drivers/staging/lustre/lustre/llite/rw26.c
@@ -489,7 +489,7 @@ static int ll_write_begin(struct file *file, struct address_space *mapping,
                          struct page **pagep, void **fsdata)
 {
        struct ll_cl_context *lcc;
-       struct lu_env  *env;
+       const struct lu_env  *env;
        struct cl_io   *io;
        struct cl_page *page;
        struct cl_object *clob = ll_i2info(mapping->host)->lli_clob;
@@ -501,9 +501,9 @@ static int ll_write_begin(struct file *file, struct address_space *mapping,
 
        CDEBUG(D_VFSTRACE, "Writing %lu of %d to %d bytes\n", index, from, len);
 
-       lcc = ll_cl_init(file, NULL);
-       if (IS_ERR(lcc)) {
-               result = PTR_ERR(lcc);
+       lcc = ll_cl_find(file);
+       if (!lcc) {
+               result = -EIO;
                goto out;
        }
 
@@ -579,8 +579,6 @@ out:
                        unlock_page(vmpage);
                        put_page(vmpage);
                }
-               if (!IS_ERR(lcc))
-                       ll_cl_fini(lcc);
        } else {
                *pagep = vmpage;
                *fsdata = lcc;
@@ -593,7 +591,7 @@ static int ll_write_end(struct file *file, struct address_space *mapping,
                        struct page *vmpage, void *fsdata)
 {
        struct ll_cl_context *lcc = fsdata;
-       struct lu_env *env;
+       const struct lu_env *env;
        struct cl_io *io;
        struct vvp_io *vio;
        struct cl_page *page;
@@ -631,6 +629,10 @@ static int ll_write_end(struct file *file, struct address_space *mapping,
        } else {
                cl_page_disown(env, io, page);
 
+               lcc->lcc_page = NULL;
+               lu_ref_del(&page->cp_reference, "cl_io", io);
+               cl_page_put(env, page);
+
                /* page list is not contiguous now, commit it now */
                unplug = true;
        }
@@ -639,7 +641,6 @@ static int ll_write_end(struct file *file, struct address_space *mapping,
            file->f_flags & O_SYNC || IS_SYNC(file_inode(file)))
                result = vvp_io_write_commit(env, io);
 
-       ll_cl_fini(lcc);
        return result >= 0 ? copied : result;
 }