Re: [PATCH] basic perf support for sparc

[Jens Axboe <jens.axboe@oracle.com>]

On Sun, Aug 02 2009, David Miller wrote:
> From: Jens Axboe <jens.axboe@oracle.com>
> Date: Wed, 29 Jul 2009 13:25:10 +0200
> 
> > -#define NR_SYSCALLS		327
> > +#define NR_SYSCALLS		328
> 
> When you increase this value, you have to add entries to all of the
> syscall tables.  The syscall dispatch checks against this as a limit,
> so if you don't explicitly add an entry to all the tables, it's
> possible to deref garbage past the end of the table and try to jump to
> it as a syscall.

Oops, missed the 32-bit table. Does the below look better?

> And if you somehow arrange for adding a compat syscall entry here for
> this, and build the perf tools 32-bit, you can forego all of these
> rediculious issues with trying to get a 64-bit BFD library.  If the
> perf tools are written portably and use types like u64 etc. for
> holding addresses and similar things, this should not be an issue.
> 
> The 32-bit sparc BFD library has full support for all the 64-bit
> binary formats and whatnot.

I'm assuming that this will happen automatically at some point, instead
of perf defaulting to building with the same 32/64-bit of the kernel.

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 3f8b6a9..2f951a9 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -44,6 +44,7 @@ config SPARC64
 	select RTC_DRV_BQ4802
 	select RTC_DRV_SUN4V
 	select RTC_DRV_STARFIRE
+	select HAVE_PERF_COUNTERS
 
 config ARCH_DEFCONFIG
 	string
diff --git a/arch/sparc/include/asm/unistd.h b/arch/sparc/include/asm/unistd.h
index b2c406d..706df66 100644
--- a/arch/sparc/include/asm/unistd.h
+++ b/arch/sparc/include/asm/unistd.h
@@ -395,8 +395,9 @@
 #define __NR_preadv		324
 #define __NR_pwritev		325
 #define __NR_rt_tgsigqueueinfo	326
+#define __NR_perf_counter_open	327
 
-#define NR_SYSCALLS		327
+#define NR_SYSCALLS		328
 
 #ifdef __32bit_syscall_numbers__
 /* Sparc 32-bit only has the "setresuid32", "getresuid32" variants,
diff --git a/arch/sparc/kernel/systbls_32.S b/arch/sparc/kernel/systbls_32.S
index 6909016..0418157 100644
--- a/arch/sparc/kernel/systbls_32.S
+++ b/arch/sparc/kernel/systbls_32.S
@@ -82,5 +82,5 @@ sys_call_table:
 /*310*/	.long sys_utimensat, sys_signalfd, sys_timerfd_create, sys_eventfd, sys_fallocate
 /*315*/	.long sys_timerfd_settime, sys_timerfd_gettime, sys_signalfd4, sys_eventfd2, sys_epoll_create1
 /*320*/	.long sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, sys_preadv
-/*325*/	.long sys_pwritev, sys_rt_tgsigqueueinfo
+/*325*/	.long sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_counter_open
 
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 6b3ee88..80ebf20 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -158,4 +158,4 @@ sys_call_table:
 /*310*/	.word sys_utimensat, sys_signalfd, sys_timerfd_create, sys_eventfd, sys_fallocate
 	.word sys_timerfd_settime, sys_timerfd_gettime, sys_signalfd4, sys_eventfd2, sys_epoll_create1
 /*320*/	.word sys_dup3, sys_pipe2, sys_inotify_init1, sys_accept4, sys_preadv
-	.word sys_pwritev, sys_rt_tgsigqueueinfo
+	.word sys_pwritev, sys_rt_tgsigqueueinfo, sys_perf_counter_open
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index e5148e2..2abeb20 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -41,6 +41,12 @@
 #define cpu_relax()	asm volatile("" ::: "memory");
 #endif
 
+#ifdef __sparc__
+#include "../../arch/sparc/include/asm/unistd.h"
+#define rmb()		asm volatile("":::"memory")
+#define cpu_relax()	asm volatile("":::"memory")
+#endif
+
 #include <time.h>
 #include <unistd.h>
 #include <sys/types.h>

-- 
Jens Axboe