commit 9ca8e40c130c906c1060d105e63628410c860261
author Jack Steiner <steiner@sgi.com> Tue Jul 29 22:34:02 2008 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> Wed Jul 30 09:41:48 2008 -0700
tree f43ec77a814039d2317c3012810b049c221e14ec
parent 3d919e5f6b440bb0cc7996eb7628b29be09e6343

GRU Driver V3: fixes to resolve code review comments

Fixes problems identified in a code review:
	- add comment with high level dscription of the GRU
	- prepend "gru_" to all global names
	- delete unused function
	- couple of trivial bug fixes

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc/sgi-gru/grumain.c

diff --git a/drivers/misc/sgi-gru/grumain.c b/drivers/misc/sgi-gru/grumain.c
index aef6822..0eeb8dd 100644
--- a/drivers/misc/sgi-gru/grumain.c
+++ b/drivers/misc/sgi-gru/grumain.c
@@ -22,7 +22,7 @@
 #include "grutables.h"
 #include "gruhandles.h"
 
-unsigned long options __read_mostly;
+unsigned long gru_options __read_mostly;
 
 static struct device_driver gru_driver = {
 	.name = "gru"
@@ -163,14 +163,14 @@
 	return bits;
 }
 
-unsigned long reserve_gru_cb_resources(struct gru_state *gru, int cbr_au_count,
+unsigned long gru_reserve_cb_resources(struct gru_state *gru, int cbr_au_count,
 				       char *cbmap)
 {
 	return reserve_resources(&gru->gs_cbr_map, cbr_au_count, GRU_CBR_AU,
 				 cbmap);
 }
 
-unsigned long reserve_gru_ds_resources(struct gru_state *gru, int dsr_au_count,
+unsigned long gru_reserve_ds_resources(struct gru_state *gru, int dsr_au_count,
 				       char *dsmap)
 {
 	return reserve_resources(&gru->gs_dsr_map, dsr_au_count, GRU_DSR_AU,
@@ -182,10 +182,10 @@
 {
 	gru->gs_active_contexts++;
 	gts->ts_cbr_map =
-	    reserve_gru_cb_resources(gru, gts->ts_cbr_au_count,
+	    gru_reserve_cb_resources(gru, gts->ts_cbr_au_count,
 				     gts->ts_cbr_idx);
 	gts->ts_dsr_map =
-	    reserve_gru_ds_resources(gru, gts->ts_dsr_au_count, NULL);
+	    gru_reserve_ds_resources(gru, gts->ts_dsr_au_count, NULL);
 }
 
 static void free_gru_resources(struct gru_state *gru,
@@ -416,6 +416,7 @@
 
 /*
  * Prefetching cachelines help hardware performance.
+ * (Strictly a performance enhancement. Not functionally required).
  */
 static void prefetch_data(void *p, int num, int stride)
 {
@@ -746,6 +747,8 @@
  * gru_nopage
  *
  * Map the user's GRU segment
+ *
+ * 	Note: gru segments alway mmaped on GRU_GSEG_PAGESIZE boundaries.
  */
 int gru_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
@@ -757,6 +760,7 @@
 		vma, vaddr, GSEG_BASE(vaddr));
 	STAT(nopfn);
 
+	/* The following check ensures vaddr is a valid address in the VMA */
 	gts = gru_find_thread_state(vma, TSID(vaddr, vma));
 	if (!gts)
 		return VM_FAULT_SIGBUS;
@@ -775,7 +779,7 @@
 	}
 
 	if (!gts->ts_gru) {
-		while (!gru_assign_gru_context(gts)) {
+		if (!gru_assign_gru_context(gts)) {
 			mutex_unlock(&gts->ts_ctxlock);
 			preempt_enable();
 			schedule_timeout(GRU_ASSIGN_DELAY);  /* true hack ZZZ */