x86: perfctr-watchdog.c - coding style cleanup
authorCyrill Gorcunov <gorcunov@gmail.com>
Tue, 24 Jun 2008 20:52:03 +0000 (22:52 +0200)
committerIngo Molnar <mingo@elte.hu>
Tue, 8 Jul 2008 10:51:39 +0000 (12:51 +0200)
Just some code beautification. Nothing else.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: macro@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/kernel/cpu/perfctr-watchdog.c

index ddda4b64f545793e125aface72bc1dbba08b2c9b..2e9bef6e3aa3d8ee0f778164725f024b6b7c388f 100644 (file)
@@ -1,11 +1,15 @@
-/* local apic based NMI watchdog for various CPUs.
-   This file also handles reservation of performance counters for coordination
-   with other users (like oprofile).
-
-   Note that these events normally don't tick when the CPU idles. This means
-   the frequency varies with CPU load.
-
-   Original code for K7/P6 written by Keith Owens */
+/*
+ * local apic based NMI watchdog for various CPUs.
+ *
+ * This file also handles reservation of performance counters for coordination
+ * with other users (like oprofile).
+ *
+ * Note that these events normally don't tick when the CPU idles. This means
+ * the frequency varies with CPU load.
+ *
+ * Original code for K7/P6 written by Keith Owens
+ *
+ */
 
 #include <linux/percpu.h>
 #include <linux/module.h>
@@ -36,12 +40,16 @@ struct wd_ops {
 
 static const struct wd_ops *wd_ops;
 
-/* this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's
- * offset from MSR_P4_BSU_ESCR0.  It will be the max for all platforms (for now)
+/*
+ * this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's
+ * offset from MSR_P4_BSU_ESCR0.
+ *
+ * It will be the max for all platforms (for now)
  */
 #define NMI_MAX_COUNTER_BITS 66
 
-/* perfctr_nmi_owner tracks the ownership of the perfctr registers:
+/*
+ * perfctr_nmi_owner tracks the ownership of the perfctr registers:
  * evtsel_nmi_owner tracks the ownership of the event selection
  * - different performance counters/ event selection may be reserved for
  *   different subsystems this reservation system just tries to coordinate
@@ -73,8 +81,10 @@ static inline unsigned int nmi_perfctr_msr_to_bit(unsigned int msr)
        return 0;
 }
 
-/* converts an msr to an appropriate reservation bit */
-/* returns the bit offset of the event selection register */
+/*
+ * converts an msr to an appropriate reservation bit
+ * returns the bit offset of the event selection register
+ */
 static inline unsigned int nmi_evntsel_msr_to_bit(unsigned int msr)
 {
        /* returns the bit offset of the event selection register */
@@ -114,6 +124,7 @@ int avail_to_resrv_perfctr_nmi(unsigned int msr)
 
        return (!test_bit(counter, perfctr_nmi_owner));
 }
+EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi_bit);
 
 int reserve_perfctr_nmi(unsigned int msr)
 {
@@ -128,6 +139,7 @@ int reserve_perfctr_nmi(unsigned int msr)
                return 1;
        return 0;
 }
+EXPORT_SYMBOL(reserve_perfctr_nmi);
 
 void release_perfctr_nmi(unsigned int msr)
 {
@@ -140,6 +152,7 @@ void release_perfctr_nmi(unsigned int msr)
 
        clear_bit(counter, perfctr_nmi_owner);
 }
+EXPORT_SYMBOL(release_perfctr_nmi);
 
 int reserve_evntsel_nmi(unsigned int msr)
 {
@@ -154,6 +167,7 @@ int reserve_evntsel_nmi(unsigned int msr)
                return 1;
        return 0;
 }
+EXPORT_SYMBOL(reserve_evntsel_nmi);
 
 void release_evntsel_nmi(unsigned int msr)
 {
@@ -166,11 +180,6 @@ void release_evntsel_nmi(unsigned int msr)
 
        clear_bit(counter, evntsel_nmi_owner);
 }
-
-EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi_bit);
-EXPORT_SYMBOL(reserve_perfctr_nmi);
-EXPORT_SYMBOL(release_perfctr_nmi);
-EXPORT_SYMBOL(reserve_evntsel_nmi);
 EXPORT_SYMBOL(release_evntsel_nmi);
 
 void disable_lapic_nmi_watchdog(void)
@@ -234,8 +243,8 @@ static unsigned int adjust_for_32bit_ctr(unsigned int hz)
        return retval;
 }
 
-static void
-write_watchdog_counter(unsigned int perfctr_msr, const char *descr, unsigned nmi_hz)
+static void write_watchdog_counter(unsigned int perfctr_msr,
+                               const char *descr, unsigned nmi_hz)
 {
        u64 count = (u64)cpu_khz * 1000;
 
@@ -246,7 +255,7 @@ write_watchdog_counter(unsigned int perfctr_msr, const char *descr, unsigned nmi
 }
 
 static void write_watchdog_counter32(unsigned int perfctr_msr,
-               const char *descr, unsigned nmi_hz)
+                               const char *descr, unsigned nmi_hz)
 {
        u64 count = (u64)cpu_khz * 1000;
 
@@ -256,9 +265,10 @@ static void write_watchdog_counter32(unsigned int perfctr_msr,
        wrmsr(perfctr_msr, (u32)(-count), 0);
 }
 
-/* AMD K7/K8/Family10h/Family11h support. AMD keeps this interface
-   nicely stable so there is not much variety */
-
+/*
+ * AMD K7/K8/Family10h/Family11h support.
+ * AMD keeps this interface nicely stable so there is not much variety
+ */
 #define K7_EVNTSEL_ENABLE      (1 << 22)
 #define K7_EVNTSEL_INT         (1 << 20)
 #define K7_EVNTSEL_OS          (1 << 17)
@@ -291,7 +301,7 @@ static int setup_k7_watchdog(unsigned nmi_hz)
 
        wd->perfctr_msr = perfctr_msr;
        wd->evntsel_msr = evntsel_msr;
-       wd->cccr_msr = 0;  //unused
+       wd->cccr_msr = 0;  /* unused */
        return 1;
 }
 
@@ -327,18 +337,19 @@ static void single_msr_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
 }
 
 static const struct wd_ops k7_wd_ops = {
-       .reserve = single_msr_reserve,
-       .unreserve = single_msr_unreserve,
-       .setup = setup_k7_watchdog,
-       .rearm = single_msr_rearm,
-       .stop = single_msr_stop_watchdog,
-       .perfctr = MSR_K7_PERFCTR0,
-       .evntsel = MSR_K7_EVNTSEL0,
-       .checkbit = 1ULL<<47,
+       .reserve        = single_msr_reserve,
+       .unreserve      = single_msr_unreserve,
+       .setup          = setup_k7_watchdog,
+       .rearm          = single_msr_rearm,
+       .stop           = single_msr_stop_watchdog,
+       .perfctr        = MSR_K7_PERFCTR0,
+       .evntsel        = MSR_K7_EVNTSEL0,
+       .checkbit       = 1ULL << 47,
 };
 
-/* Intel Model 6 (PPro+,P2,P3,P-M,Core1) */
-
+/*
+ * Intel Model 6 (PPro+,P2,P3,P-M,Core1)
+ */
 #define P6_EVNTSEL0_ENABLE     (1 << 22)
 #define P6_EVNTSEL_INT         (1 << 20)
 #define P6_EVNTSEL_OS          (1 << 17)
@@ -374,52 +385,58 @@ static int setup_p6_watchdog(unsigned nmi_hz)
 
        wd->perfctr_msr = perfctr_msr;
        wd->evntsel_msr = evntsel_msr;
-       wd->cccr_msr = 0;  //unused
+       wd->cccr_msr = 0;  /* unused */
        return 1;
 }
 
 static void p6_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
 {
-       /* P6 based Pentium M need to re-unmask
+       /*
+        * P6 based Pentium M need to re-unmask
         * the apic vector but it doesn't hurt
         * other P6 variant.
-        * ArchPerfom/Core Duo also needs this */
+        * ArchPerfom/Core Duo also needs this
+        */
        apic_write(APIC_LVTPC, APIC_DM_NMI);
+
        /* P6/ARCH_PERFMON has 32 bit counter write */
        write_watchdog_counter32(wd->perfctr_msr, NULL,nmi_hz);
 }
 
 static const struct wd_ops p6_wd_ops = {
-       .reserve = single_msr_reserve,
-       .unreserve = single_msr_unreserve,
-       .setup = setup_p6_watchdog,
-       .rearm = p6_rearm,
-       .stop = single_msr_stop_watchdog,
-       .perfctr = MSR_P6_PERFCTR0,
-       .evntsel = MSR_P6_EVNTSEL0,
-       .checkbit = 1ULL<<39,
+       .reserve        = single_msr_reserve,
+       .unreserve      = single_msr_unreserve,
+       .setup          = setup_p6_watchdog,
+       .rearm          = p6_rearm,
+       .stop           = single_msr_stop_watchdog,
+       .perfctr        = MSR_P6_PERFCTR0,
+       .evntsel        = MSR_P6_EVNTSEL0,
+       .checkbit       = 1ULL << 39,
 };
 
-/* Intel P4 performance counters. By far the most complicated of all. */
-
-#define MSR_P4_MISC_ENABLE_PERF_AVAIL  (1<<7)
-#define P4_ESCR_EVENT_SELECT(N)        ((N)<<25)
-#define P4_ESCR_OS             (1<<3)
-#define P4_ESCR_USR            (1<<2)
-#define P4_CCCR_OVF_PMI0       (1<<26)
-#define P4_CCCR_OVF_PMI1       (1<<27)
-#define P4_CCCR_THRESHOLD(N)   ((N)<<20)
-#define P4_CCCR_COMPLEMENT     (1<<19)
-#define P4_CCCR_COMPARE                (1<<18)
-#define P4_CCCR_REQUIRED       (3<<16)
-#define P4_CCCR_ESCR_SELECT(N) ((N)<<13)
-#define P4_CCCR_ENABLE         (1<<12)
-#define P4_CCCR_OVF            (1<<31)
-
-/* Set up IQ_COUNTER0 to behave like a clock, by having IQ_CCCR0 filter
-   CRU_ESCR0 (with any non-null event selector) through a complemented
-   max threshold. [IA32-Vol3, Section 14.9.9] */
+/*
+ * Intel P4 performance counters.
+ * By far the most complicated of all.
+ */
+#define MSR_P4_MISC_ENABLE_PERF_AVAIL  (1 << 7)
+#define P4_ESCR_EVENT_SELECT(N)        ((N) << 25)
+#define P4_ESCR_OS             (1 << 3)
+#define P4_ESCR_USR            (1 << 2)
+#define P4_CCCR_OVF_PMI0       (1 << 26)
+#define P4_CCCR_OVF_PMI1       (1 << 27)
+#define P4_CCCR_THRESHOLD(N)   ((N) << 20)
+#define P4_CCCR_COMPLEMENT     (1 << 19)
+#define P4_CCCR_COMPARE                (1 << 18)
+#define P4_CCCR_REQUIRED       (3 << 16)
+#define P4_CCCR_ESCR_SELECT(N) ((N) << 13)
+#define P4_CCCR_ENABLE         (1 << 12)
+#define P4_CCCR_OVF            (1 << 31)
 
+/*
+ * Set up IQ_COUNTER0 to behave like a clock, by having IQ_CCCR0 filter
+ * CRU_ESCR0 (with any non-null event selector) through a complemented
+ * max threshold. [IA32-Vol3, Section 14.9.9]
+ */
 static int setup_p4_watchdog(unsigned nmi_hz)
 {
        unsigned int perfctr_msr, evntsel_msr, cccr_msr;
@@ -444,7 +461,8 @@ static int setup_p4_watchdog(unsigned nmi_hz)
 #endif
                ht_num = 0;
 
-       /* performance counters are shared resources
+       /*
+        * performance counters are shared resources
         * assign each hyperthread its own set
         * (re-use the ESCR0 register, seems safe
         * and keeps the cccr_val the same)
@@ -542,20 +560,21 @@ static void p4_rearm(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz)
 }
 
 static const struct wd_ops p4_wd_ops = {
-       .reserve = p4_reserve,
-       .unreserve = p4_unreserve,
-       .setup = setup_p4_watchdog,
-       .rearm = p4_rearm,
-       .stop = stop_p4_watchdog,
+       .reserve        = p4_reserve,
+       .unreserve      = p4_unreserve,
+       .setup          = setup_p4_watchdog,
+       .rearm          = p4_rearm,
+       .stop           = stop_p4_watchdog,
        /* RED-PEN this is wrong for the other sibling */
-       .perfctr = MSR_P4_BPU_PERFCTR0,
-       .evntsel = MSR_P4_BSU_ESCR0,
-       .checkbit = 1ULL<<39,
+       .perfctr        = MSR_P4_BPU_PERFCTR0,
+       .evntsel        = MSR_P4_BSU_ESCR0,
+       .checkbit       = 1ULL << 39,
 };
 
-/* Watchdog using the Intel architected PerfMon. Used for Core2 and hopefully
-   all future Intel CPUs. */
-
+/*
+ * Watchdog using the Intel architected PerfMon.
+ * Used for Core2 and hopefully all future Intel CPUs.
+ */
 #define ARCH_PERFMON_NMI_EVENT_SEL     ARCH_PERFMON_UNHALTED_CORE_CYCLES_SEL
 #define ARCH_PERFMON_NMI_EVENT_UMASK   ARCH_PERFMON_UNHALTED_CORE_CYCLES_UMASK
 
@@ -601,19 +620,19 @@ static int setup_intel_arch_watchdog(unsigned nmi_hz)
 
        wd->perfctr_msr = perfctr_msr;
        wd->evntsel_msr = evntsel_msr;
-       wd->cccr_msr = 0;  //unused
+       wd->cccr_msr = 0;  /* unused */
        intel_arch_wd_ops.checkbit = 1ULL << (eax.split.bit_width - 1);
        return 1;
 }
 
 static struct wd_ops intel_arch_wd_ops __read_mostly = {
-       .reserve = single_msr_reserve,
-       .unreserve = single_msr_unreserve,
-       .setup = setup_intel_arch_watchdog,
-       .rearm = p6_rearm,
-       .stop = single_msr_stop_watchdog,
-       .perfctr = MSR_ARCH_PERFMON_PERFCTR1,
-       .evntsel = MSR_ARCH_PERFMON_EVENTSEL1,
+       .reserve        = single_msr_reserve,
+       .unreserve      = single_msr_unreserve,
+       .setup          = setup_intel_arch_watchdog,
+       .rearm          = p6_rearm,
+       .stop           = single_msr_stop_watchdog,
+       .perfctr        = MSR_ARCH_PERFMON_PERFCTR1,
+       .evntsel        = MSR_ARCH_PERFMON_EVENTSEL1,
 };
 
 static void probe_nmi_watchdog(void)
@@ -626,8 +645,10 @@ static void probe_nmi_watchdog(void)
                wd_ops = &k7_wd_ops;
                break;
        case X86_VENDOR_INTEL:
-               /* Work around Core Duo (Yonah) errata AE49 where perfctr1
-                  doesn't have a working enable bit. */
+               /*
+                * Work around Core Duo (Yonah) errata AE49 where perfctr1
+                * doesn't have a working enable bit.
+                */
                if (boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 14) {
                        intel_arch_wd_ops.perfctr = MSR_ARCH_PERFMON_PERFCTR0;
                        intel_arch_wd_ops.evntsel = MSR_ARCH_PERFMON_EVENTSEL0;
@@ -638,7 +659,7 @@ static void probe_nmi_watchdog(void)
                }
                switch (boot_cpu_data.x86) {
                case 6:
-                       if (boot_cpu_data.x86_model > 0xd)
+                       if (boot_cpu_data.x86_model > 13)
                                return;
 
                        wd_ops = &p6_wd_ops;
@@ -699,10 +720,11 @@ int lapic_wd_event(unsigned nmi_hz)
 {
        struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
        u64 ctr;
+
        rdmsrl(wd->perfctr_msr, ctr);
-       if (ctr & wd_ops->checkbit) /* perfctr still running? */
+       if (ctr & wd_ops->checkbit) /* perfctr still running? */
                return 0;
-       }
+
        wd_ops->rearm(wd, nmi_hz);
        return 1;
 }