[PATCH v3] powerpc32: provide VIRT_CPU_ACCOUNTING
From: Christophe Leroy
Date: Wed Feb 10 2016 - 09:58:57 EST
This patch provides VIRT_CPU_ACCOUTING to PPC32 architecture.
PPC32 doesn't have the PACA structure, so we use the task_info
structure to store the accounting data.
In order to reuse on PPC32 the PPC64 functions, all u64 data has
been replaced by 'unsigned long' so that it is u32 on PPC32 and
u64 on PPC64
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
Changes in v3: unlike previous version of the patch that was inspired
from IA64 architecture, this new version tries to reuse as much as
possible the PPC64 implementation.
PPC32 doesn't have PACA and past discusion on v2 version has shown
that it is not worth implementing a PACA in PPC32 architecture
(see below benh opinion)
benh: PACA is actually a data structure and you really really don't want it
on ppc32 :-) Having a register point to current works, having a register
point to per-cpu data instead works too (ie, change what we do today),
but don't introduce a PACA *please* :-)
arch/powerpc/Kconfig | 1 +
arch/powerpc/include/asm/cputime.h | 4 ++++
arch/powerpc/include/asm/ppc_asm.h | 31 ++++++++++++++++-----------
arch/powerpc/include/asm/reg.h | 1 +
arch/powerpc/include/asm/thread_info.h | 11 ++++++++++
arch/powerpc/kernel/asm-offsets.c | 5 +++++
arch/powerpc/kernel/entry_32.S | 17 +++++++++++++++
arch/powerpc/kernel/entry_64.S | 6 +++---
arch/powerpc/kernel/time.c | 38 +++++++++++++++++++++++++++-------
arch/powerpc/platforms/Kconfig.cputype | 1 -
10 files changed, 92 insertions(+), 23 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3a557be..57ce4ff 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -159,6 +159,7 @@ config PPC
select ARCH_HAS_DEVMEM_IS_ALLOWED
select HAVE_ARCH_SECCOMP_FILTER
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select HAVE_VIRT_CPU_ACCOUNTING
config GENERIC_CSUM
def_bool CPU_LITTLE_ENDIAN
diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h
index e245255..c4c33be 100644
--- a/arch/powerpc/include/asm/cputime.h
+++ b/arch/powerpc/include/asm/cputime.h
@@ -230,7 +230,11 @@ static inline cputime_t clock_t_to_cputime(const unsigned long clk)
#define cputime64_to_clock_t(ct) cputime_to_clock_t((cputime_t)(ct))
+#ifdef CONFIG_PPC64
static inline void arch_vtime_task_switch(struct task_struct *tsk) { }
+#else
+void arch_vtime_task_switch(struct task_struct *tsk);
+#endif
#endif /* __KERNEL__ */
#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index 499d9f8..05b6738 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -24,27 +24,34 @@
*/
#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
-#define ACCOUNT_CPU_USER_ENTRY(ra, rb)
-#define ACCOUNT_CPU_USER_EXIT(ra, rb)
+#define ACCOUNT_CPU_USER_ENTRY(ptr, ra, rb)
+#define ACCOUNT_CPU_USER_EXIT(ptr, ra, rb)
#define ACCOUNT_STOLEN_TIME
#else
-#define ACCOUNT_CPU_USER_ENTRY(ra, rb) \
+#ifdef CONFIG_PPC64
+#define AC_LD ld
+#define AC_STD std
+#else
+#define AC_LD lwz
+#define AC_STD stw
+#endif
+#define ACCOUNT_CPU_USER_ENTRY(ptr, ra, rb) \
MFTB(ra); /* get timebase */ \
- ld rb,PACA_STARTTIME_USER(r13); \
- std ra,PACA_STARTTIME(r13); \
+ AC_LD rb, PACA_STARTTIME_USER(ptr); \
+ AC_STD ra, PACA_STARTTIME(ptr); \
subf rb,rb,ra; /* subtract start value */ \
- ld ra,PACA_USER_TIME(r13); \
+ AC_LD ra, PACA_USER_TIME(ptr); \
add ra,ra,rb; /* add on to user time */ \
- std ra,PACA_USER_TIME(r13); \
+ AC_STD ra, PACA_USER_TIME(ptr); \
-#define ACCOUNT_CPU_USER_EXIT(ra, rb) \
+#define ACCOUNT_CPU_USER_EXIT(ptr, ra, rb) \
MFTB(ra); /* get timebase */ \
- ld rb,PACA_STARTTIME(r13); \
- std ra,PACA_STARTTIME_USER(r13); \
+ AC_LD rb, PACA_STARTTIME(ptr); \
+ AC_STD ra, PACA_STARTTIME_USER(ptr); \
subf rb,rb,ra; /* subtract start value */ \
- ld ra,PACA_SYSTEM_TIME(r13); \
+ AC_LD ra, PACA_SYSTEM_TIME(ptr); \
add ra,ra,rb; /* add on to system time */ \
- std ra,PACA_SYSTEM_TIME(r13)
+ AC_STD ra, PACA_SYSTEM_TIME(ptr)
#ifdef CONFIG_PPC_SPLPAR
#define ACCOUNT_STOLEN_TIME \
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index c4cb2ff..ff6b591 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -1275,6 +1275,7 @@ static inline unsigned long mfvtb (void)
asm volatile("mfspr %0, %1" : "=r" (rval) : \
"i" (SPRN_TBRU)); rval;})
#endif
+#define mftb() mftbl()
#endif /* !__powerpc64__ */
#define mttbl(v) asm volatile("mttbl %0":: "r"(v))
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index 7efee4a..4f19e96 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -44,6 +44,17 @@ struct thread_info {
<0 => BUG */
unsigned long local_flags; /* private flags for thread */
+#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC32)
+ /* Stuff for accurate time accounting */
+ unsigned long user_time; /* accumulated usermode TB ticks */
+ unsigned long system_time; /* accumulated system TB ticks */
+ unsigned long user_time_scaled; /* accumulated usermode SPURR ticks */
+ unsigned long starttime; /* TB value snapshot */
+ unsigned long starttime_user; /* TB value on exit to usermode */
+ unsigned long startspurr; /* SPURR value snapshot */
+ unsigned long utime_sspurr; /* ->user_time when ->startspurr set */
+#endif
+
/* low level flags - has atomic operations done on it */
unsigned long flags ____cacheline_aligned_in_smp;
};
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 07cebc3..ea91dd8 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -256,6 +256,11 @@ int main(void)
DEFINE(PACA_TRAP_SAVE, offsetof(struct paca_struct, trap_save));
DEFINE(PACA_NAPSTATELOST, offsetof(struct paca_struct, nap_state_lost));
DEFINE(PACA_SPRG_VDSO, offsetof(struct paca_struct, sprg_vdso));
+#else /* CONFIG_PPC64 */
+ DEFINE(PACA_STARTTIME, offsetof(struct thread_info, starttime));
+ DEFINE(PACA_STARTTIME_USER, offsetof(struct thread_info, starttime_user));
+ DEFINE(PACA_USER_TIME, offsetof(struct thread_info, user_time));
+ DEFINE(PACA_SYSTEM_TIME, offsetof(struct thread_info, system_time));
#endif /* CONFIG_PPC64 */
/* RTAS */
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 2405631..9899032 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -175,6 +175,12 @@ transfer_to_handler:
addi r12,r12,-1
stw r12,4(r11)
#endif
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ CURRENT_THREAD_INFO(r9, r1)
+ tophys(r9, r9)
+ ACCOUNT_CPU_USER_ENTRY(r9, r11, r12)
+#endif
+
b 3f
2: /* if from kernel, check interrupted DOZE/NAP mode and
@@ -398,6 +404,13 @@ BEGIN_FTR_SECTION
lwarx r7,0,r1
END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
stwcx. r0,0,r1 /* to clear the reservation */
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ andi. r4,r8,MSR_PR
+ beq 3f
+ CURRENT_THREAD_INFO(r4, r1)
+ ACCOUNT_CPU_USER_EXIT(r4, r5, r7)
+3:
+#endif
lwz r4,_LINK(r1)
lwz r5,_CCR(r1)
mtlr r4
@@ -769,6 +782,10 @@ restore_user:
andis. r10,r0,DBCR0_IDM@h
bnel- load_dbcr0
#endif
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
+ CURRENT_THREAD_INFO(r9, r1)
+ ACCOUNT_CPU_USER_EXIT(r9, r10, r11)
+#endif
b restore
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 0d525ce..d9bf82b 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -70,7 +70,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
std r0,GPR0(r1)
std r10,GPR1(r1)
beq 2f /* if from kernel mode */
- ACCOUNT_CPU_USER_ENTRY(r10, r11)
+ ACCOUNT_CPU_USER_ENTRY(r13, r10, r11)
2: std r2,GPR2(r1)
std r3,GPR3(r1)
mfcr r2
@@ -222,7 +222,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
ld r4,_LINK(r1)
beq- 1f
- ACCOUNT_CPU_USER_EXIT(r11, r12)
+ ACCOUNT_CPU_USER_EXIT(r13, r11, r12)
BEGIN_FTR_SECTION
HMT_MEDIUM_LOW
@@ -822,7 +822,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
BEGIN_FTR_SECTION
mtspr SPRN_PPR,r2 /* Restore PPR */
END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
- ACCOUNT_CPU_USER_EXIT(r2, r4)
+ ACCOUNT_CPU_USER_EXIT(r13, r2, r4)
REST_GPR(13, r1)
1:
mtspr SPRN_SRR1,r3
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 81b0900..6307b09 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -165,7 +165,13 @@ DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta);
cputime_t cputime_one_jiffy;
+#ifdef CONFIG_PPC_SPLPAR
void (*dtl_consumer)(struct dtl_entry *, u64);
+#endif
+
+#ifdef CONFIG_PPC32
+#define get_paca() task_thread_info(tsk)
+#endif
static void calc_cputime_factors(void)
{
@@ -185,7 +191,7 @@ static void calc_cputime_factors(void)
* Read the SPURR on systems that have it, otherwise the PURR,
* or if that doesn't exist return the timebase value passed in.
*/
-static u64 read_spurr(u64 tb)
+static unsigned long read_spurr(unsigned long tb)
{
if (cpu_has_feature(CPU_FTR_SPURR))
return mfspr(SPRN_SPURR);
@@ -294,11 +300,12 @@ static inline u64 calculate_stolen_time(u64 stop_tb)
* Account time for a transition between system, hard irq
* or soft irq state.
*/
-static u64 vtime_delta(struct task_struct *tsk,
- u64 *sys_scaled, u64 *stolen)
+static unsigned long vtime_delta(struct task_struct *tsk,
+ unsigned long *sys_scaled,
+ unsigned long *stolen)
{
- u64 now, nowscaled, deltascaled;
- u64 udelta, delta, user_scaled;
+ unsigned long now, nowscaled, deltascaled;
+ unsigned long udelta, delta, user_scaled;
WARN_ON_ONCE(!irqs_disabled());
@@ -343,7 +350,7 @@ static u64 vtime_delta(struct task_struct *tsk,
void vtime_account_system(struct task_struct *tsk)
{
- u64 delta, sys_scaled, stolen;
+ unsigned long delta, sys_scaled, stolen;
delta = vtime_delta(tsk, &sys_scaled, &stolen);
account_system_time(tsk, 0, delta, sys_scaled);
@@ -354,7 +361,7 @@ EXPORT_SYMBOL_GPL(vtime_account_system);
void vtime_account_idle(struct task_struct *tsk)
{
- u64 delta, sys_scaled, stolen;
+ unsigned long delta, sys_scaled, stolen;
delta = vtime_delta(tsk, &sys_scaled, &stolen);
account_idle_time(delta + stolen);
@@ -381,6 +388,23 @@ void vtime_account_user(struct task_struct *tsk)
account_user_time(tsk, utime, utimescaled);
}
+#ifdef CONFIG_PPC32
+/*
+ * Called from the context switch with interrupts disabled, to charge all
+ * accumulated times to the current process, and to prepare accounting on
+ * the next process.
+ */
+void arch_vtime_task_switch(struct task_struct *prev)
+{
+ struct thread_info *pi = task_thread_info(prev);
+ struct thread_info *ni = task_thread_info(current);
+
+ ni->starttime = pi->starttime;
+ ni->system_time = 0;
+ ni->user_time = 0;
+}
+#endif /* CONFIG_PPC32 */
+
#else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
#define calc_cputime_factors()
#endif
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 142dff5..54b8043 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -1,7 +1,6 @@
config PPC64
bool "64-bit kernel"
default n
- select HAVE_VIRT_CPU_ACCOUNTING
select ZLIB_DEFLATE
help
This option selects whether a 32-bit or a 64-bit kernel
--
2.1.0