diff options
| author | Rusty Russell <rusty@rustcorp.com.au> | 2008-03-04 23:07:50 +1100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-04-17 17:40:52 +0200 |
| commit | 3c2047cd32b1a8c782d7efab72707e7daa251625 (patch) | |
| tree | 79a3481d5f7b637626d0cf346dc1f1042d68c07f /arch/x86/kernel/tsc_32.c | |
| parent | 9fc34113f6880b215cbea4e7017fc818700384c2 (diff) | |
x86: if we cannot calibrate the TSC, we panic.
The current tsc_init() clears the TSC feature bit if the TSC khz
cannot be calculated, causing us to panic in
arch/x86/kernel/cpu/bugs.c check_config(). We should simply mark it
unstable.
Frankly, someone should take an axe to this code. mark_tsc_unstable()
not only marks it unstable, but sets tsc_enabled to 0, which seems
redundant but is actually important here because means it won't be
used by sched_clock() either. Perhaps a tristate enum "UNUSABLE,
UNSTABLE, OK" would be clearer, and separate mark_tsc_unstable() and
mark_tsc_broken() functions?
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/tsc_32.c')
| -rw-r--r-- | arch/x86/kernel/tsc_32.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c index c2241e04ea5f..68657d8526fb 100644 --- a/arch/x86/kernel/tsc_32.c +++ b/arch/x86/kernel/tsc_32.c @@ -392,13 +392,15 @@ void __init tsc_init(void) int cpu; if (!cpu_has_tsc) - goto out_no_tsc; + return; cpu_khz = calculate_cpu_khz(); tsc_khz = cpu_khz; - if (!cpu_khz) - goto out_no_tsc; + if (!cpu_khz) { + mark_tsc_unstable("could not calculate TSC khz"); + return; + } printk("Detected %lu.%03lu MHz processor.\n", (unsigned long)cpu_khz / 1000, @@ -431,9 +433,4 @@ void __init tsc_init(void) tsc_enabled = 1; clocksource_register(&clocksource_tsc); - - return; - -out_no_tsc: - setup_clear_cpu_cap(X86_FEATURE_TSC); } |