2008-11-03 19:19:25

by Alok Kataria

Subject: [PATCH] x86: Don't use tsc_khz to calculate lpj if notsc is passed.

x86: Don't use tsc_khz to calculate lpj if notsc is passed.

From: Alok N Kataria <[email protected]>

With notsc passed on commandline, tsc may not be used for
udelays, make sure that we do not use tsc_khz to calculate
the lpj value in such cases.

Signed-off-by: Alok N Kataria <[email protected]>
Cc: [email protected]

---

arch/x86/kernel/tsc.c | 8 ++++----
1 files changed, 4 insertions(+), 4 deletions(-)


diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index ee01cd9..8904571 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -829,10 +829,6 @@ void __init tsc_init(void)
cpu_khz = calibrate_cpu();
#endif

- lpj = ((u64)tsc_khz * 1000);
- do_div(lpj, HZ);
- lpj_fine = lpj;
-
printk("Detected %lu.%03lu MHz processor.\n",
(unsigned long)cpu_khz / 1000,
(unsigned long)cpu_khz % 1000);
@@ -852,6 +848,10 @@ void __init tsc_init(void)
/* now allow native_sched_clock() to use rdtsc */
tsc_disabled = 0;

+ lpj = ((u64)tsc_khz * 1000);
+ do_div(lpj, HZ);
+ lpj_fine = lpj;
+
use_tsc_delay();
/* Check and install the TSC clocksource */
dmi_check_system(bad_tsc_dmi_table);

2008-11-04 08:55:37

by Ingo Molnar

Subject: Re: [PATCH] x86: Don't use tsc_khz to calculate lpj if notsc is passed.

* Alok Kataria <[email protected]> wrote:

> x86: Don't use tsc_khz to calculate lpj if notsc is passed.
>
> From: Alok N Kataria <[email protected]>
>
> With notsc passed on commandline, tsc may not be used for
> udelays, make sure that we do not use tsc_khz to calculate
> the lpj value in such cases.
>
> Signed-off-by: Alok N Kataria <[email protected]>
> Cc: [email protected]

applied to tip/x86/urgent, thanks Alok!

btw., i fixed this error checkpatch noticed:

ERROR: trailing whitespace
#41: FILE: arch/x86/kernel/tsc.c:838:
+^I$

total: 1 errors, 0 warnings, 0 checks, 20 lines checked

Ingo