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author | David S. Miller <davem@davemloft.net> | 2008-06-10 05:22:26 -0400 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2008-06-10 05:22:26 -0400 |
commit | 65b53e4cc90e59936733b3b95b9451d2ca47528d (patch) | |
tree | 29932718192962671c48c3fd1ea017a6112459e8 /arch/x86/kernel/tsc_32.c | |
parent | 788c0a53164c05c5ccdb1472474372b72ba74644 (diff) | |
parent | 2e761e0532a784816e7e822dbaaece8c5d4be14d (diff) |
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
drivers/net/tg3.c
drivers/net/wireless/rt2x00/rt2x00dev.c
net/mac80211/ieee80211_i.h
Diffstat (limited to 'arch/x86/kernel/tsc_32.c')
-rw-r--r-- | arch/x86/kernel/tsc_32.c | 25 |
1 files changed, 15 insertions, 10 deletions
diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c index e4790728b224..068759db63dd 100644 --- a/arch/x86/kernel/tsc_32.c +++ b/arch/x86/kernel/tsc_32.c | |||
@@ -14,7 +14,7 @@ | |||
14 | 14 | ||
15 | #include "mach_timer.h" | 15 | #include "mach_timer.h" |
16 | 16 | ||
17 | static int tsc_enabled; | 17 | static int tsc_disabled; |
18 | 18 | ||
19 | /* | 19 | /* |
20 | * On some systems the TSC frequency does not | 20 | * On some systems the TSC frequency does not |
@@ -28,8 +28,8 @@ EXPORT_SYMBOL_GPL(tsc_khz); | |||
28 | static int __init tsc_setup(char *str) | 28 | static int __init tsc_setup(char *str) |
29 | { | 29 | { |
30 | printk(KERN_WARNING "notsc: Kernel compiled with CONFIG_X86_TSC, " | 30 | printk(KERN_WARNING "notsc: Kernel compiled with CONFIG_X86_TSC, " |
31 | "cannot disable TSC completely.\n"); | 31 | "cannot disable TSC completely.\n"); |
32 | mark_tsc_unstable("user disabled TSC"); | 32 | tsc_disabled = 1; |
33 | return 1; | 33 | return 1; |
34 | } | 34 | } |
35 | #else | 35 | #else |
@@ -120,7 +120,7 @@ unsigned long long native_sched_clock(void) | |||
120 | * very important for it to be as fast as the platform | 120 | * very important for it to be as fast as the platform |
121 | * can achive it. ) | 121 | * can achive it. ) |
122 | */ | 122 | */ |
123 | if (unlikely(!tsc_enabled && !tsc_unstable)) | 123 | if (unlikely(tsc_disabled)) |
124 | /* No locking but a rare wrong value is not a big deal: */ | 124 | /* No locking but a rare wrong value is not a big deal: */ |
125 | return (jiffies_64 - INITIAL_JIFFIES) * (1000000000 / HZ); | 125 | return (jiffies_64 - INITIAL_JIFFIES) * (1000000000 / HZ); |
126 | 126 | ||
@@ -322,7 +322,6 @@ void mark_tsc_unstable(char *reason) | |||
322 | { | 322 | { |
323 | if (!tsc_unstable) { | 323 | if (!tsc_unstable) { |
324 | tsc_unstable = 1; | 324 | tsc_unstable = 1; |
325 | tsc_enabled = 0; | ||
326 | printk("Marking TSC unstable due to: %s.\n", reason); | 325 | printk("Marking TSC unstable due to: %s.\n", reason); |
327 | /* Can be called before registration */ | 326 | /* Can be called before registration */ |
328 | if (clocksource_tsc.mult) | 327 | if (clocksource_tsc.mult) |
@@ -336,7 +335,7 @@ EXPORT_SYMBOL_GPL(mark_tsc_unstable); | |||
336 | static int __init dmi_mark_tsc_unstable(const struct dmi_system_id *d) | 335 | static int __init dmi_mark_tsc_unstable(const struct dmi_system_id *d) |
337 | { | 336 | { |
338 | printk(KERN_NOTICE "%s detected: marking TSC unstable.\n", | 337 | printk(KERN_NOTICE "%s detected: marking TSC unstable.\n", |
339 | d->ident); | 338 | d->ident); |
340 | tsc_unstable = 1; | 339 | tsc_unstable = 1; |
341 | return 0; | 340 | return 0; |
342 | } | 341 | } |
@@ -403,14 +402,22 @@ void __init tsc_init(void) | |||
403 | { | 402 | { |
404 | int cpu; | 403 | int cpu; |
405 | 404 | ||
406 | if (!cpu_has_tsc) | 405 | if (!cpu_has_tsc || tsc_disabled) { |
406 | /* Disable the TSC in case of !cpu_has_tsc */ | ||
407 | tsc_disabled = 1; | ||
407 | return; | 408 | return; |
409 | } | ||
408 | 410 | ||
409 | cpu_khz = calculate_cpu_khz(); | 411 | cpu_khz = calculate_cpu_khz(); |
410 | tsc_khz = cpu_khz; | 412 | tsc_khz = cpu_khz; |
411 | 413 | ||
412 | if (!cpu_khz) { | 414 | if (!cpu_khz) { |
413 | mark_tsc_unstable("could not calculate TSC khz"); | 415 | mark_tsc_unstable("could not calculate TSC khz"); |
416 | /* | ||
417 | * We need to disable the TSC completely in this case | ||
418 | * to prevent sched_clock() from using it. | ||
419 | */ | ||
420 | tsc_disabled = 1; | ||
414 | return; | 421 | return; |
415 | } | 422 | } |
416 | 423 | ||
@@ -441,8 +448,6 @@ void __init tsc_init(void) | |||
441 | if (check_tsc_unstable()) { | 448 | if (check_tsc_unstable()) { |
442 | clocksource_tsc.rating = 0; | 449 | clocksource_tsc.rating = 0; |
443 | clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS; | 450 | clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS; |
444 | } else | 451 | } |
445 | tsc_enabled = 1; | ||
446 | |||
447 | clocksource_register(&clocksource_tsc); | 452 | clocksource_register(&clocksource_tsc); |
448 | } | 453 | } |