Re: [RFC][git-pull -tip] x86: cpu_debug and cpufeature patches

From: Jaswinder Singh Rajput
Date: Wed May 06 2009 - 08:51:08 EST

On Wed, 2009-05-06 at 14:25 +0200, Ingo Molnar wrote:
> >
> > +/* Advanced Power Management (Function 8000_0007h), edx */
> > +#define X86_FEATURE_TS (9*32+ 0) /* Temperatue sensor */
> > +#define X86_FEATURE_FID (9*32+ 1) /* Frequency ID control */
> > +#define X86_FEATURE_VID (9*32+ 2) /* Voltage ID control */
> > +#define X86_FEATURE_TTP (9*32+ 3) /* Thermal trip */
> > +#define X86_FEATURE_HTC (9*32+ 4) /* Hardware thermal control */
> > +#define X86_FEATURE_STC (9*32+ 5) /* Software thermal control */
> > +#define X86_FEATURE_100MHZSTEPS (9*32+ 6) /* 100 MHz multiplier control */
> > +#define X86_FEATURE_HWPSTATE (9*32+ 7) /* Hardware P-State control */
> > +#define X86_FEATURE_CONSTANT_TSC (9*32+ 8) /* Constant rate TSC ticks */
> > +
>
> Yes, this general approach looks pretty good! Note how it reduces
> the line count in fact.
>

Yes, thanks :-)

> I havent looked deeply yet, but noticed that above you changed
> X86_FEATURE_CONSTANT_TSC - why was that done?
>

X86_FEATURE_CONSTANT_TSC is used as TSC Invariant of Power Management
EDX[8]. Now I made complete Advanced Power Management group so I moved
it down here.

Here is the complete Advanced Power Management patch, it is a big patch,
if you want I can further divide it:

Subject: [PATCH] x86: Add cpufeatures for Advanced Power Management

1. Add Advanced Power Management (Function 8000_0007h), edx
2. unification of X86_FEATURE_CONSTANT_TSC (from intel.c, amd.c to common.c)
3. Remove cpu/powerflags.c
4. Remove x86_power
5. Move 'power management' to flags of /proc/cpuinfo

/proc/cpuinfo (before)
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt
rdtscp lm 3dnowext 3dnow constant_tsc rep_good nonstop_tsc pni cx16
lahf_lm cmp_legacy svm extapic cr8_legacy 3dnowprefetch osvw skinit pname
..
power management: ts ttp tm stc 100mhzsteps hwpstate

/proc/cpuinfo (after)
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge
mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt
rdtscp lm 3dnowext 3dnow rep_good tsc_reliable nonstop_tsc pni cx16
lahf_lm cmp_legacy svm extapic cr8_legacy 3dnowprefetch osvw skinit pname
ts ttp htc stc 100mhzsteps hwpstate constant_tsc

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@xxxxxxxxx>
---
arch/x86/include/asm/cpufeature.h | 15 ++++++++++++---
arch/x86/include/asm/processor.h | 1 -
arch/x86/kernel/cpu/Makefile | 2 +-
arch/x86/kernel/cpu/amd.c | 9 ---------
arch/x86/kernel/cpu/common.c | 15 ++++++++++++++-
arch/x86/kernel/cpu/intel.c | 14 --------------
arch/x86/kernel/cpu/powerflags.c | 20 --------------------
arch/x86/kernel/cpu/proc.c | 14 --------------
8 files changed, 27 insertions(+), 63 deletions(-)
delete mode 100644 arch/x86/kernel/cpu/powerflags.c

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 6fabb6c..db04825 100644
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -6,7 +6,7 @@

#include <asm/required-features.h>

-#define NCAPINTS 9 /* N 32-bit words worth of info */
+#define NCAPINTS 10 /* N 32-bit words worth of info */

/*
* Note: If the comment begins with a quoted string, that string is used
@@ -76,7 +76,6 @@
#define X86_FEATURE_K7 (3*32+ 5) /* "" Athlon */
#define X86_FEATURE_P3 (3*32+ 6) /* "" P3 */
#define X86_FEATURE_P4 (3*32+ 7) /* "" P4 */
-#define X86_FEATURE_CONSTANT_TSC (3*32+ 8) /* TSC ticks at a constant rate */
#define X86_FEATURE_UP (3*32+ 9) /* smp kernel running on up */
#define X86_FEATURE_FXSAVE_LEAK (3*32+10) /* "" FXSAVE leaks FOP/FIP/FOP */
#define X86_FEATURE_ARCH_PERFMON (3*32+11) /* Intel Architectural PerfMon */
@@ -164,12 +163,22 @@
#define X86_FEATURE_EPT (8*32+ 3) /* Intel Extended Page Table */
#define X86_FEATURE_VPID (8*32+ 4) /* Intel Virtual Processor ID */

+/* Advanced Power Management (Function 8000_0007h), edx */
+#define X86_FEATURE_TS (9*32+ 0) /* Temperatue sensor */
+#define X86_FEATURE_FID (9*32+ 1) /* Frequency ID control */
+#define X86_FEATURE_VID (9*32+ 2) /* Voltage ID control */
+#define X86_FEATURE_TTP (9*32+ 3) /* Thermal trip */
+#define X86_FEATURE_HTC (9*32+ 4) /* Hardware thermal control */
+#define X86_FEATURE_STC (9*32+ 5) /* Software thermal control */
+#define X86_FEATURE_100MHZSTEPS (9*32+ 6) /* 100 MHz multiplier control */
+#define X86_FEATURE_HWPSTATE (9*32+ 7) /* Hardware P-State control */
+#define X86_FEATURE_CONSTANT_TSC (9*32+ 8) /* Constant rate TSC ticks */
+
#if defined(__KERNEL__) && !defined(__ASSEMBLY__)

#include <linux/bitops.h>

extern const char * const x86_cap_flags[NCAPINTS*32];
-extern const char * const x86_power_flags[32];

#define test_cpu_cap(c, bit) \
test_bit(bit, (unsigned long *)((c)->x86_capability))
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 0b2fab0..deabe4a 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -90,7 +90,6 @@ struct cpuinfo_x86 {
/* in KB - valid for CPUS which support this call: */
int x86_cache_size;
int x86_cache_alignment; /* In bytes */
- int x86_power;
unsigned long loops_per_jiffy;
#ifdef CONFIG_SMP
/* cpus sharing the last level cache: */
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 3efcb2b..b43fcbb 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -8,7 +8,7 @@ CFLAGS_REMOVE_common.o = -pg
endif

obj-y := intel_cacheinfo.o addon_cpuid_features.o
-obj-y += proc.o capflags.o powerflags.o common.o
+obj-y += proc.o capflags.o common.o
obj-y += vmware.o hypervisor.o

obj-$(CONFIG_X86_32) += bugs.o cmpxchg.o
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 7e4a459..2c1931f 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -333,15 +333,6 @@ static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
{
early_init_amd_mc(c);

- /*
- * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
- * with P/T states and does not stop in deep C-states
- */
- if (c->x86_power & (1 << 8)) {
- set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
- set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
- }
-
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSCALL32);
#else
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 827e93d..9d71629 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -576,8 +576,21 @@ static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
#endif

if (c->extended_cpuid_level >= 0x80000007)
- c->x86_power = cpuid_edx(0x80000007);
+ c->x86_capability[9] = cpuid_edx(0x80000007);

+ /*
+ * Advanced power management is 8000_0007 edx.
+ * Bit 8 is TSC runs at constant rate with P/T states
+ * and does not stop in deep C-states.
+ *
+ * It is also reliable across cores and sockets. (but not across
+ * cabinets - we turn it off in that case explicitly.)
+ */
+ if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
+ set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+ set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE);
+ sched_clock_stable = 1;
+ }
}

static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
diff --git a/arch/x86/kernel/cpu/intel.c b/arch/x86/kernel/cpu/intel.c
index 5dac7bd..361e7e5 100644
--- a/arch/x86/kernel/cpu/intel.c
+++ b/arch/x86/kernel/cpu/intel.c
@@ -61,20 +61,6 @@ static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
c->x86_phys_bits = 36;

/*
- * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
- * with P/T states and does not stop in deep C-states.
- *
- * It is also reliable across cores and sockets. (but not across
- * cabinets - we turn it off in that case explicitly.)
- */
- if (c->x86_power & (1 << 8)) {
- set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
- set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
- set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE);
- sched_clock_stable = 1;
- }
-
- /*
* There is a known erratum on Pentium III and Core Solo
* and Core Duo CPUs.
* " Page with PAT set to WC while associated MTRR is UC
diff --git a/arch/x86/kernel/cpu/powerflags.c b/arch/x86/kernel/cpu/powerflags.c
deleted file mode 100644
index 5abbea2..0000000
--- a/arch/x86/kernel/cpu/powerflags.c
+++ /dev/null
@@ -1,20 +0,0 @@
-/*
- * Strings for the various x86 power flags
- *
- * This file must not contain any executable code.
- */
-
-#include <asm/cpufeature.h>
-
-const char *const x86_power_flags[32] = {
- "ts", /* temperature sensor */
- "fid", /* frequency id control */
- "vid", /* voltage id control */
- "ttp", /* thermal trip */
- "tm",
- "stc",
- "100mhzsteps",
- "hwpstate",
- "", /* tsc invariant mapped to constant_tsc */
- /* nothing */
-};
diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c
index f93047f..523bf39 100644
--- a/arch/x86/kernel/cpu/proc.c
+++ b/arch/x86/kernel/cpu/proc.c
@@ -121,20 +121,6 @@ static int show_cpuinfo(struct seq_file *m, void *v)
seq_printf(m, "address sizes\t: %u bits physical, %u bits virtual\n",
c->x86_phys_bits, c->x86_virt_bits);
#endif
-
- seq_printf(m, "power management:");
- for (i = 0; i < 32; i++) {
- if (c->x86_power & (1 << i)) {
- if (i < ARRAY_SIZE(x86_power_flags) &&
- x86_power_flags[i])
- seq_printf(m, "%s%s",
- x86_power_flags[i][0]?" ":"",
- x86_power_flags[i]);
- else
- seq_printf(m, " [%d]", i);
- }
- }
-
seq_printf(m, "\n\n");

return 0;
--
1.6.0.6



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