[RFC PATCH 2/6] perf: Generalize callchain_store()

Prev: [RFC PATCH 5/6] perf: Fix race in callchains
Next: perf: Generalize some arch callchain code

From: Frederic Weisbecker on 1 Jul 2010 11:40

---

callchain_store() is the same on every archs, inline it in
perf_event.h and rename it to perf_callchain_store() to avoid
any collision.

This removes repetitive code.

Signed-off-by: Frederic Weisbecker <fweisbec(a)gmail.com>
Cc: Ingo Molnar <mingo(a)elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra(a)chello.nl>
Cc: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Cc: Paul Mackerras <paulus(a)samba.org>
Cc: Stephane Eranian <eranian(a)google.com>
Cc: David Miller <davem(a)davemloft.net>
Cc: Paul Mundt <lethal(a)linux-sh.org>
Cc: Will Deacon <will.deacon(a)arm.com>
Cc: Borislav Petkov <bp(a)amd64.org>
---
arch/arm/kernel/perf_event.c | 15 +++---------
arch/powerpc/kernel/perf_callchain.c | 40 ++++++++++++----------------------
arch/sh/kernel/perf_callchain.c | 11 ++------
arch/sparc/kernel/perf_event.c | 26 ++++++++-------------
arch/x86/kernel/cpu/perf_event.c | 20 ++++++-----------
include/linux/perf_event.h | 7 ++++++
6 files changed, 45 insertions(+), 74 deletions(-)

diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 16519f6..41de647 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -3001,13 +3001,6 @@ arch_initcall(init_hw_perf_events);
/*
* Callchain handling code.
*/
-static inline void
-callchain_store(struct perf_callchain_entry *entry,
- u64 ip)
-{
- if (entry->nr < PERF_MAX_STACK_DEPTH)
- entry->ip[entry->nr++] = ip;
-}

/*
* The registers we're interested in are at the end of the variable
@@ -3039,7 +3032,7 @@ user_backtrace(struct frame_tail *tail,
if (__copy_from_user_inatomic(&buftail, tail, sizeof(buftail)))
return NULL;

- callchain_store(entry, buftail.lr);
+ perf_callchain_store(entry, buftail.lr);

/*
* Frame pointers should strictly progress back up the stack
@@ -3057,7 +3050,7 @@ perf_callchain_user(struct pt_regs *regs,
{
struct frame_tail *tail;

- callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);

if (!user_mode(regs))
regs = task_pt_regs(current);
@@ -3078,7 +3071,7 @@ callchain_trace(struct stackframe *fr,
void *data)
{
struct perf_callchain_entry *entry = data;
- callchain_store(entry, fr->pc);
+ perf_callchain_store(entry, fr->pc);
return 0;
}

@@ -3088,7 +3081,7 @@ perf_callchain_kernel(struct pt_regs *regs,
{
struct stackframe fr;

- callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
fr.fp = regs->ARM_fp;
fr.sp = regs->ARM_sp;
fr.lr = regs->ARM_lr;
diff --git a/arch/powerpc/kernel/perf_callchain.c b/arch/powerpc/kernel/perf_callchain.c
index 95ad9da..a286c2e 100644
--- a/arch/powerpc/kernel/perf_callchain.c
+++ b/arch/powerpc/kernel/perf_callchain.c
@@ -23,18 +23,6 @@
#include "ppc32.h"
#endif

-/*
- * Store another value in a callchain_entry.
- */
-static inline void callchain_store(struct perf_callchain_entry *entry, u64 ip)
-{
- unsigned int nr = entry->nr;
-
- if (nr < PERF_MAX_STACK_DEPTH) {
- entry->ip[nr] = ip;
- entry->nr = nr + 1;
- }
-}

/*
* Is sp valid as the address of the next kernel stack frame after prev_sp?
@@ -69,8 +57,8 @@ static void perf_callchain_kernel(struct pt_regs *regs,

lr = regs->link;
sp = regs->gpr[1];
- callchain_store(entry, PERF_CONTEXT_KERNEL);
- callchain_store(entry, regs->nip);
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_store(entry, regs->nip);

if (!validate_sp(sp, current, STACK_FRAME_OVERHEAD))
return;
@@ -89,7 +77,7 @@ static void perf_callchain_kernel(struct pt_regs *regs,
next_ip = regs->nip;
lr = regs->link;
level = 0;
- callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);

} else {
if (level == 0)
@@ -111,7 +99,7 @@ static void perf_callchain_kernel(struct pt_regs *regs,
++level;
}

- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, next_ip);
if (!valid_next_sp(next_sp, sp))
return;
sp = next_sp;
@@ -246,8 +234,8 @@ static void perf_callchain_user_64(struct pt_regs *regs,
next_ip = regs->nip;
lr = regs->link;
sp = regs->gpr[1];
- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, next_ip);

for (;;) {
fp = (unsigned long __user *) sp;
@@ -276,14 +264,14 @@ static void perf_callchain_user_64(struct pt_regs *regs,
read_user_stack_64(&uregs[PT_R1], &sp))
return;
level = 0;
- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, next_ip);
continue;
}

if (level == 0)
next_ip = lr;
- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, next_ip);
++level;
sp = next_sp;
}
@@ -447,8 +435,8 @@ static void perf_callchain_user_32(struct pt_regs *regs,
next_ip = regs->nip;
lr = regs->link;
sp = regs->gpr[1];
- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, next_ip);

while (entry->nr < PERF_MAX_STACK_DEPTH) {
fp = (unsigned int __user *) (unsigned long) sp;
@@ -470,14 +458,14 @@ static void perf_callchain_user_32(struct pt_regs *regs,
read_user_stack_32(&uregs[PT_R1], &sp))
return;
level = 0;
- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, next_ip);
continue;
}

if (level == 0)
next_ip = lr;
- callchain_store(entry, next_ip);
+ perf_callchain_store(entry, next_ip);
++level;
sp = next_sp;
}
diff --git a/arch/sh/kernel/perf_callchain.c b/arch/sh/kernel/perf_callchain.c
index 1d6dbce..00143f3 100644
--- a/arch/sh/kernel/perf_callchain.c
+++ b/arch/sh/kernel/perf_callchain.c
@@ -14,11 +14,6 @@
#include <asm/unwinder.h>
#include <asm/ptrace.h>

-static inline void callchain_store(struct perf_callchain_entry *entry, u64 ip)
-{
- if (entry->nr < PERF_MAX_STACK_DEPTH)
- entry->ip[entry->nr++] = ip;
-}

static void callchain_warning(void *data, char *msg)
{
@@ -39,7 +34,7 @@ static void callchain_address(void *data, unsigned long addr, int reliable)
struct perf_callchain_entry *entry = data;

if (reliable)
- callchain_store(entry, addr);
+ perf_callchain_store(entry, addr);
}

static const struct stacktrace_ops callchain_ops = {
@@ -52,8 +47,8 @@ static const struct stacktrace_ops callchain_ops = {
static void
perf_callchain_kernel(struct pt_regs *regs, struct perf_callchain_entry *entry)
{
- callchain_store(entry, PERF_CONTEXT_KERNEL);
- callchain_store(entry, regs->pc);
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_store(entry, regs->pc);

unwind_stack(NULL, regs, NULL, &callchain_ops, entry);
}
diff --git a/arch/sparc/kernel/perf_event.c b/arch/sparc/kernel/perf_event.c
index 8a6660d..fbac5ad 100644
--- a/arch/sparc/kernel/perf_event.c
+++ b/arch/sparc/kernel/perf_event.c
@@ -1282,12 +1282,6 @@ void __init init_hw_perf_events(void)
register_die_notifier(&perf_event_nmi_notifier);
}

-static inline void callchain_store(struct perf_callchain_entry *entry, u64 ip)
-{
- if (entry->nr < PERF_MAX_STACK_DEPTH)
- entry->ip[entry->nr++] = ip;
-}
-
static void perf_callchain_kernel(struct pt_regs *regs,
struct perf_callchain_entry *entry)
{
@@ -1296,8 +1290,8 @@ static void perf_callchain_kernel(struct pt_regs *regs,
int graph = 0;
#endif

- callchain_store(entry, PERF_CONTEXT_KERNEL);
- callchain_store(entry, regs->tpc);
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_store(entry, regs->tpc);

ksp = regs->u_regs[UREG_I6];
fp = ksp + STACK_BIAS;
@@ -1321,13 +1315,13 @@ static void perf_callchain_kernel(struct pt_regs *regs,
pc = sf->callers_pc;
fp = (unsigned long)sf->fp + STACK_BIAS;
}
- callchain_store(entry, pc);
+ perf_callchain_store(entry, pc);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
if ((pc + 8UL) == (unsigned long) &return_to_handler) {
int index = current->curr_ret_stack;
if (current->ret_stack && index >= graph) {
pc = current->ret_stack[index - graph].ret;
- callchain_store(entry, pc);
+ perf_callchain_store(entry, pc);
graph++;
}
}
@@ -1340,8 +1334,8 @@ static void perf_callchain_user_64(struct pt_regs *regs,
{
unsigned long ufp;

- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, regs->tpc);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, regs->tpc);

ufp = regs->u_regs[UREG_I6] + STACK_BIAS;
do {
@@ -1354,7 +1348,7 @@ static void perf_callchain_user_64(struct pt_regs *regs,

pc = sf.callers_pc;
ufp = (unsigned long)sf.fp + STACK_BIAS;
- callchain_store(entry, pc);
+ perf_callchain_store(entry, pc);
} while (entry->nr < PERF_MAX_STACK_DEPTH);
}

@@ -1363,8 +1357,8 @@ static void perf_callchain_user_32(struct pt_regs *regs,
{
unsigned long ufp;

- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, regs->tpc);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, regs->tpc);

ufp = regs->u_regs[UREG_I6] & 0xffffffffUL;
do {
@@ -1377,7 +1371,7 @@ static void perf_callchain_user_32(struct pt_regs *regs,

pc = sf.callers_pc;
ufp = (unsigned long)sf.fp;
- callchain_store(entry, pc);
+ perf_callchain_store(entry, pc);
} while (entry->nr < PERF_MAX_STACK_DEPTH);
}

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 4a4d191..8af28ca 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -1571,12 +1571,6 @@ const struct pmu *hw_perf_event_init(struct perf_event *event)
* callchain support
*/

-static inline
-void callchain_store(struct perf_callchain_entry *entry, u64 ip)
-{
- if (entry->nr < PERF_MAX_STACK_DEPTH)
- entry->ip[entry->nr++] = ip;
-}

static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_irq_entry);
static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_nmi_entry);
@@ -1602,7 +1596,7 @@ static void backtrace_address(void *data, unsigned long addr, int reliable)
{
struct perf_callchain_entry *entry = data;

- callchain_store(entry, addr);
+ perf_callchain_store(entry, addr);
}

static const struct stacktrace_ops backtrace_ops = {
@@ -1616,8 +1610,8 @@ static const struct stacktrace_ops backtrace_ops = {
static void
perf_callchain_kernel(struct pt_regs *regs, struct perf_callchain_entry *entry)
{
- callchain_store(entry, PERF_CONTEXT_KERNEL);
- callchain_store(entry, regs->ip);
+ perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
+ perf_callchain_store(entry, regs->ip);

dump_trace(NULL, regs, NULL, regs->bp, &backtrace_ops, entry);
}
@@ -1646,7 +1640,7 @@ perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry)
if (fp < compat_ptr(regs->sp))
break;

- callchain_store(entry, frame.return_address);
+ perf_callchain_store(entry, frame.return_address);
fp = compat_ptr(frame.next_frame);
}
return 1;
@@ -1670,8 +1664,8 @@ perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry)

fp = (void __user *)regs->bp;

- callchain_store(entry, PERF_CONTEXT_USER);
- callchain_store(entry, regs->ip);
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, regs->ip);

if (perf_callchain_user32(regs, entry))
return;
@@ -1688,7 +1682,7 @@ perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry)
if ((unsigned long)fp < regs->sp)
break;

- callchain_store(entry, frame.return_address);
+ perf_callchain_store(entry, frame.return_address);
fp = frame.next_frame;
}
}
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 937495c..3588804 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -978,6 +978,13 @@ extern void perf_event_fork(struct task_struct *tsk);

extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs);

+static inline void
+perf_callchain_store(struct perf_callchain_entry *entry, u64 ip)
+{
+ if (entry->nr < PERF_MAX_STACK_DEPTH)
+ entry->ip[entry->nr++] = ip;
+}
+
extern int sysctl_perf_event_paranoid;
extern int sysctl_perf_event_mlock;
extern int sysctl_perf_event_sample_rate;
--
1.6.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

 | 
Pages: 1
Prev: [RFC PATCH 5/6] perf: Fix race in callchains
Next: perf: Generalize some arch callchain code