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-rw-r--r--drivers/misc/sgi-xp/xp.h11
1 files changed, 3 insertions, 8 deletions
diff --git a/drivers/misc/sgi-xp/xp.h b/drivers/misc/sgi-xp/xp.h
index 955b5b913235..0ca81f16646f 100644
--- a/drivers/misc/sgi-xp/xp.h
+++ b/drivers/misc/sgi-xp/xp.h
@@ -21,7 +21,7 @@
21#include <asm/sn/arch.h> 21#include <asm/sn/arch.h>
22#endif 22#endif
23 23
24/* >>> Add this #define to some linux header file some day. */ 24/* ??? Add this #define to some linux header file some day? */
25#define BYTES_PER_WORD sizeof(void *) 25#define BYTES_PER_WORD sizeof(void *)
26 26
27#ifdef USE_DBUG_ON 27#ifdef USE_DBUG_ON
@@ -65,18 +65,13 @@
65 * other partition that is currently up. Over these channels, kernel-level 65 * other partition that is currently up. Over these channels, kernel-level
66 * `users' can communicate with their counterparts on the other partitions. 66 * `users' can communicate with their counterparts on the other partitions.
67 * 67 *
68>>> The following described limitation of a max of eight channels possible
69>>> pertains only to ia64-sn2. THIS ISN'T TRUE SINCE I'M PLANNING TO JUST
70>>> TIE INTO THE EXISTING MECHANISM ONCE THE CHANNEL MESSAGES ARE RECEIVED.
71>>> THE 128-BYTE CACHELINE PERFORMANCE ISSUE IS TIED TO IA64-SN2.
72 *
73 * If the need for additional channels arises, one can simply increase 68 * If the need for additional channels arises, one can simply increase
74 * XPC_MAX_NCHANNELS accordingly. If the day should come where that number 69 * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
75 * exceeds the absolute MAXIMUM number of channels possible (eight), then one 70 * exceeds the absolute MAXIMUM number of channels possible (eight), then one
76 * will need to make changes to the XPC code to accommodate for this. 71 * will need to make changes to the XPC code to accommodate for this.
77 * 72 *
78 * The absolute maximum number of channels possible is currently limited to 73 * The absolute maximum number of channels possible is limited to eight for
79 * eight for performance reasons. The internal cross partition structures 74 * performance reasons on sn2 hardware. The internal cross partition structures
80 * require sixteen bytes per channel, and eight allows all of this 75 * require sixteen bytes per channel, and eight allows all of this
81 * interface-shared info to fit in one 128-byte cacheline. 76 * interface-shared info to fit in one 128-byte cacheline.
82 */ 77 */