Revision dda50e716dc9451f40eebfb2902c260e4f62cf34 authored by Andi Kleen on 17 May 2005, 04:53:25 UTC, committed by Linus Torvalds on 17 May 2005, 14:59:14 UTC
The new TSC sync algorithm recently submitted did not work too well. The result was that some MP machines where the TSC came up of the BIOS very unsynchronized and that did not have HPET support were nearly unusable because the time would jump forwards and backwards between CPUs. After a lot of research ;-) and some more prototypes I ended up with just using the one from IA64 which looks best. It has some internal self tuning that should adapt to changing interconnect latencies. It holds up in my tests so far. I believe it was originally written by David Mosberger, I just ported it over to x86-64. See the inline comment for a description. This cleans up the code because it uses smp_call_function for syncing instead of having custom hooks in SMP bootup. Please note that the cycle numbers it outputs are too optimistic because they do not take into account the latency of WRMSR and RDTSC, which can be hundreds of cycles. It seems to be able to sync a dual Opteron to 200-300 cycles, which is probably good enough. There is a timing window during AP bootup where interrupts can see inconsistent time before the TSC is synced. It is hard to avoid unfortunately because we can only do the TSC sync after some setup, and we need to enable interrupts before that. I just ignored it for now. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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ida_ioctl.h
/*
* Disk Array driver for Compaq SMART2 Controllers
* Copyright 1998 Compaq Computer Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Questions/Comments/Bugfixes to iss_storagedev@hp.com
*
*/
#ifndef IDA_IOCTL_H
#define IDA_IOCTL_H
#include "ida_cmd.h"
#include "cpqarray.h"
#define IDAGETDRVINFO 0x27272828
#define IDAPASSTHRU 0x28282929
#define IDAGETCTLRSIG 0x29293030
#define IDAREVALIDATEVOLS 0x30303131
#define IDADRIVERVERSION 0x31313232
#define IDAGETPCIINFO 0x32323333
typedef struct _ida_pci_info_struct
{
unsigned char bus;
unsigned char dev_fn;
__u32 board_id;
} ida_pci_info_struct;
/*
* Normally, the ioctl determines the logical unit for this command by
* the major,minor number of the fd passed to ioctl. If you need to send
* a command to a different/nonexistant unit (such as during config), you
* can override the normal behavior by setting the unit valid bit. (Normally,
* it should be zero) The controller the command is sent to is still
* determined by the major number of the open device.
*/
#define UNITVALID 0x80
typedef struct {
__u8 cmd;
__u8 rcode;
__u8 unit;
__u32 blk;
__u16 blk_cnt;
/* currently, sg_cnt is assumed to be 1: only the 0th element of sg is used */
struct {
void __user *addr;
size_t size;
} sg[SG_MAX];
int sg_cnt;
union ctlr_cmds {
drv_info_t drv;
unsigned char buf[1024];
id_ctlr_t id_ctlr;
drv_param_t drv_param;
id_log_drv_t id_log_drv;
id_log_drv_ext_t id_log_drv_ext;
sense_log_drv_stat_t sense_log_drv_stat;
id_phys_drv_t id_phys_drv;
blink_drv_leds_t blink_drv_leds;
sense_blink_leds_t sense_blink_leds;
config_t config;
reorder_log_drv_t reorder_log_drv;
label_log_drv_t label_log_drv;
surf_delay_t surf_delay;
overhead_delay_t overhead_delay;
mp_delay_t mp_delay;
scsi_param_t scsi_param;
} c;
} ida_ioctl_t;
#endif /* IDA_IOCTL_H */
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