[PATCH 11/15] sparc64: boot performance improvements

[Eric Snowberg]

Keep sun4v OF devices open.  This can save 6 - 7 seconds per open call and
can decrease boot times from over 10 minutes to a few seconds on
larger SPARC systems.  The open/close calls with some vendors'
SAS controllers cause the entire card to be reinitialized after
each close.

Signed-off-by: Eric Snowberg <address@hidden>
---
 grub-core/disk/ieee1275/ofdisk.c |   17 ++++++++++++++++-
 grub-core/kern/ieee1275/cmain.c  |    4 ++++
 include/grub/ieee1275/ieee1275.h |    2 ++
 3 files changed, 22 insertions(+), 1 deletions(-)

diff --git a/grub-core/disk/ieee1275/ofdisk.c b/grub-core/disk/ieee1275/ofdisk.c
index 6789072..9c6b8b0 100644
--- a/grub-core/disk/ieee1275/ofdisk.c
+++ b/grub-core/disk/ieee1275/ofdisk.c
@@ -37,6 +37,7 @@ struct ofdisk_hash_ent
   int is_removable;
   int block_size_retries;
   grub_uint32_t block_size;
+  grub_ieee1275_ihandle_t ihandle;
   /* Pointer to shortest available name on nodes representing canonical names,
      otherwise NULL.  */
   const char *shortest;
@@ -539,7 +540,7 @@ grub_ofdisk_close (grub_disk_t disk)
 {
   if (disk->data == last_devpath)
     {
-      if (last_ihandle)
+      if (! (grub_ieee1275_test_flag(GRUB_IEEE1275_FLAG_CACHE_OPEN)) && 
last_ihandle)
        grub_ieee1275_close (last_ihandle);
       last_ihandle = 0;
       last_devpath = NULL;
@@ -733,6 +734,18 @@ grub_ofdisk_get_block_size (grub_uint32_t *block_size, 
struct ofdisk_hash_ent *o
 static grub_err_t
 grub_ofdisk_open_real (grub_disk_t disk)
 {
+  struct ofdisk_hash_ent *op = (struct ofdisk_hash_ent *)disk->id;
+
+  if (!op)
+    return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "BUG: can't open device ");
+
+  if (grub_ieee1275_test_flag(GRUB_IEEE1275_FLAG_CACHE_OPEN) && op->ihandle)
+    {
+      last_ihandle = op->ihandle;
+      last_devpath = disk->data;
+      return 0;
+    }
+
   if (last_ihandle)
     grub_ieee1275_close (last_ihandle);
 
@@ -743,5 +756,7 @@ grub_ofdisk_open_real (grub_disk_t disk)
   if (! last_ihandle)
     return grub_error (GRUB_ERR_UNKNOWN_DEVICE, "can't open device");
 
+  op->ihandle = last_ihandle;
+  last_devpath = disk->data;
   return 0;
 }
diff --git a/grub-core/kern/ieee1275/cmain.c b/grub-core/kern/ieee1275/cmain.c
index 3e12e6b..b016598 100644
--- a/grub-core/kern/ieee1275/cmain.c
+++ b/grub-core/kern/ieee1275/cmain.c
@@ -108,6 +108,10 @@ grub_ieee1275_find_options (void)
   if (rc >= 0)
     {
       char *ptr;
+
+      if (grub_strncmp (tmp, "sun4v", 5) == 0)
+         grub_ieee1275_set_flag (GRUB_IEEE1275_FLAG_CACHE_OPEN);
+
       for (ptr = tmp; ptr - tmp < actual; ptr += grub_strlen (ptr) + 1)
        {
          if (grub_memcmp (ptr, "MacRISC", sizeof ("MacRISC") - 1) == 0
diff --git a/include/grub/ieee1275/ieee1275.h b/include/grub/ieee1275/ieee1275.h
index 8e42513..b79e97b 100644
--- a/include/grub/ieee1275/ieee1275.h
+++ b/include/grub/ieee1275/ieee1275.h
@@ -146,6 +146,8 @@ enum grub_ieee1275_flag
   GRUB_IEEE1275_FLAG_BROKEN_REPEAT,
 
   GRUB_IEEE1275_FLAG_CURSORONOFF_ANSI_BROKEN,
+
+  GRUB_IEEE1275_FLAG_CACHE_OPEN,
 };
 
 extern int EXPORT_FUNC(grub_ieee1275_test_flag) (enum grub_ieee1275_flag flag);
-- 
1.7.1