powerpc/pseries: Move dtl scanning and steal time accounting to pseries platform

dtl is the PAPR Dispatch Trace Log, which is entirely a pseries feature.
The pseries platform alrady has a file dealing with the dtl, so move
scanning for stolen time accounting there from kernel/time.c.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220902085316.2071519-5-npiggin@gmail.com

diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h
index 6d2b279..431ae23 100644 (file)
--- a/arch/powerpc/include/asm/cputime.h
+++ b/arch/powerpc/include/asm/cputime.h
@@ -95,7 +95,7 @@ static notrace inline void account_stolen_time(void)
                struct lppaca *lp = local_paca->lppaca_ptr;
 
                if (unlikely(local_paca->dtl_ridx != be64_to_cpu(lp->dtl_idx)))
-                       accumulate_stolen_time();
+                       pseries_accumulate_stolen_time();
        }
 #endif
 }

diff --git a/arch/powerpc/include/asm/dtl.h b/arch/powerpc/include/asm/dtl.h
index 1625888..4bcb9f9 100644 (file)
--- a/arch/powerpc/include/asm/dtl.h
+++ b/arch/powerpc/include/asm/dtl.h
@@ -37,14 +37,6 @@ struct dtl_entry {
 extern struct kmem_cache *dtl_cache;
 extern rwlock_t dtl_access_lock;
 
-/*
- * When CONFIG_VIRT_CPU_ACCOUNTING_NATIVE = y, the cpu accounting code controls
- * reading from the dispatch trace log.  If other code wants to consume
- * DTL entries, it can set this pointer to a function that will get
- * called once for each DTL entry that gets processed.
- */
-extern void (*dtl_consumer)(struct dtl_entry *entry, u64 index);
-
 extern void register_dtl_buffer(int cpu);
 extern void alloc_dtl_buffers(unsigned long *time_limit);
 extern long hcall_vphn(unsigned long cpu, u64 flags, __be32 *associativity);

diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h
index 1e5643a..9f50766 100644 (file)
--- a/arch/powerpc/include/asm/time.h
+++ b/arch/powerpc/include/asm/time.h
@@ -116,8 +116,9 @@ unsigned long long tb_to_ns(unsigned long long tb_ticks);
 
 void timer_broadcast_interrupt(void);
 
-/* SPLPAR */
-void accumulate_stolen_time(void);
+/* SPLPAR and VIRT_CPU_ACCOUNTING_NATIVE */
+void pseries_accumulate_stolen_time(void);
+u64 pseries_calculate_stolen_time(u64 stop_tb);
 
 #endif /* __KERNEL__ */
 #endif /* __POWERPC_TIME_H */

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 587adcc..ae3e33b 100644 (file)
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -178,92 +178,6 @@ static inline unsigned long read_spurr(unsigned long tb)
        return tb;
 }
 
-#ifdef CONFIG_PPC_SPLPAR
-
-#include <asm/dtl.h>
-
-void (*dtl_consumer)(struct dtl_entry *, u64);
-
-/*
- * Scan the dispatch trace log and count up the stolen time.
- * Should be called with interrupts disabled.
- */
-static u64 scan_dispatch_log(u64 stop_tb)
-{
-       u64 i = local_paca->dtl_ridx;
-       struct dtl_entry *dtl = local_paca->dtl_curr;
-       struct dtl_entry *dtl_end = local_paca->dispatch_log_end;
-       struct lppaca *vpa = local_paca->lppaca_ptr;
-       u64 tb_delta;
-       u64 stolen = 0;
-       u64 dtb;
-
-       if (!dtl)
-               return 0;
-
-       if (i == be64_to_cpu(vpa->dtl_idx))
-               return 0;
-       while (i < be64_to_cpu(vpa->dtl_idx)) {
-               dtb = be64_to_cpu(dtl->timebase);
-               tb_delta = be32_to_cpu(dtl->enqueue_to_dispatch_time) +
-                       be32_to_cpu(dtl->ready_to_enqueue_time);
-               barrier();
-               if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) {
-                       /* buffer has overflowed */
-                       i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG;
-                       dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG);
-                       continue;
-               }
-               if (dtb > stop_tb)
-                       break;
-               if (dtl_consumer)
-                       dtl_consumer(dtl, i);
-               stolen += tb_delta;
-               ++i;
-               ++dtl;
-               if (dtl == dtl_end)
-                       dtl = local_paca->dispatch_log;
-       }
-       local_paca->dtl_ridx = i;
-       local_paca->dtl_curr = dtl;
-       return stolen;
-}
-
-/*
- * Accumulate stolen time by scanning the dispatch trace log.
- * Called on entry from user mode.
- */
-void notrace accumulate_stolen_time(void)
-{
-       u64 sst, ust;
-       struct cpu_accounting_data *acct = &local_paca->accounting;
-
-       sst = scan_dispatch_log(acct->starttime_user);
-       ust = scan_dispatch_log(acct->starttime);
-       acct->stime -= sst;
-       acct->utime -= ust;
-       acct->steal_time += ust + sst;
-}
-
-static inline u64 calculate_stolen_time(u64 stop_tb)
-{
-       if (!firmware_has_feature(FW_FEATURE_SPLPAR))
-               return 0;
-
-       if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx))
-               return scan_dispatch_log(stop_tb);
-
-       return 0;
-}
-
-#else /* CONFIG_PPC_SPLPAR */
-static inline u64 calculate_stolen_time(u64 stop_tb)
-{
-       return 0;
-}
-
-#endif /* CONFIG_PPC_SPLPAR */
-
 /*
  * Account time for a transition between system, hard irq
  * or soft irq state.
@@ -322,7 +236,11 @@ static unsigned long vtime_delta(struct cpu_accounting_data *acct,
 
        *stime_scaled = vtime_delta_scaled(acct, now, stime);
 
-       *steal_time = calculate_stolen_time(now);
+       if (IS_ENABLED(CONFIG_PPC_SPLPAR) &&
+                       firmware_has_feature(FW_FEATURE_SPLPAR))
+               *steal_time = pseries_calculate_stolen_time(now);
+       else
+               *steal_time = 0;
 
        return stime;
 }

diff --git a/arch/powerpc/platforms/pseries/dtl.c b/arch/powerpc/platforms/pseries/dtl.c
index 352af5b..1b1977b 100644 (file)
--- a/arch/powerpc/platforms/pseries/dtl.c
+++ b/arch/powerpc/platforms/pseries/dtl.c
@@ -37,6 +37,15 @@ static u8 dtl_event_mask = DTL_LOG_ALL;
 static int dtl_buf_entries = N_DISPATCH_LOG;
 
 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+
+/*
+ * When CONFIG_VIRT_CPU_ACCOUNTING_NATIVE = y, the cpu accounting code controls
+ * reading from the dispatch trace log.  If other code wants to consume
+ * DTL entries, it can set this pointer to a function that will get
+ * called once for each DTL entry that gets processed.
+ */
+static void (*dtl_consumer)(struct dtl_entry *entry, u64 index);
+
 struct dtl_ring {
        u64     write_index;
        struct dtl_entry *write_ptr;
@@ -49,6 +58,78 @@ static DEFINE_PER_CPU(struct dtl_ring, dtl_rings);
 static atomic_t dtl_count;
 
 /*
+ * Scan the dispatch trace log and count up the stolen time.
+ * Should be called with interrupts disabled.
+ */
+static notrace u64 scan_dispatch_log(u64 stop_tb)
+{
+       u64 i = local_paca->dtl_ridx;
+       struct dtl_entry *dtl = local_paca->dtl_curr;
+       struct dtl_entry *dtl_end = local_paca->dispatch_log_end;
+       struct lppaca *vpa = local_paca->lppaca_ptr;
+       u64 tb_delta;
+       u64 stolen = 0;
+       u64 dtb;
+
+       if (!dtl)
+               return 0;
+
+       if (i == be64_to_cpu(vpa->dtl_idx))
+               return 0;
+       while (i < be64_to_cpu(vpa->dtl_idx)) {
+               dtb = be64_to_cpu(dtl->timebase);
+               tb_delta = be32_to_cpu(dtl->enqueue_to_dispatch_time) +
+                       be32_to_cpu(dtl->ready_to_enqueue_time);
+               barrier();
+               if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) {
+                       /* buffer has overflowed */
+                       i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG;
+                       dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG);
+                       continue;
+               }
+               if (dtb > stop_tb)
+                       break;
+               if (dtl_consumer)
+                       dtl_consumer(dtl, i);
+               stolen += tb_delta;
+               ++i;
+               ++dtl;
+               if (dtl == dtl_end)
+                       dtl = local_paca->dispatch_log;
+       }
+       local_paca->dtl_ridx = i;
+       local_paca->dtl_curr = dtl;
+       return stolen;
+}
+
+/*
+ * Accumulate stolen time by scanning the dispatch trace log.
+ * Called on entry from user mode.
+ */
+void notrace pseries_accumulate_stolen_time(void)
+{
+       u64 sst, ust;
+       struct cpu_accounting_data *acct = &local_paca->accounting;
+
+       sst = scan_dispatch_log(acct->starttime_user);
+       ust = scan_dispatch_log(acct->starttime);
+       acct->stime -= sst;
+       acct->utime -= ust;
+       acct->steal_time += ust + sst;
+}
+
+u64 pseries_calculate_stolen_time(u64 stop_tb)
+{
+       if (!firmware_has_feature(FW_FEATURE_SPLPAR))
+               return 0;
+
+       if (get_paca()->dtl_ridx != be64_to_cpu(get_lppaca()->dtl_idx))
+               return scan_dispatch_log(stop_tb);
+
+       return 0;
+}
+
+/*
  * The cpu accounting code controls the DTL ring buffer, and we get
  * given entries as they are processed.
  */