diff mbox series

[v7,05/11] arm64: perf: Include threshold control fields in PMEVTYPER mask

Message ID 20231211161331.1277825-6-james.clark@arm.com (mailing list archive)
State New, archived
Headers show
Series arm64: perf: Add support for event counting threshold | expand

Commit Message

James Clark Dec. 11, 2023, 4:13 p.m. UTC 
FEAT_PMUv3_TH (Armv8.8) adds two new fields to PMEVTYPER, so include
them in the mask. These aren't writable on 32 bit kernels as they are in
the high part of the register, so only include them for arm64.

It would be difficult to do this statically in the asm header files for
each platform without resulting in circular includes or #ifdefs inline
in the code. For that reason the ARMV8_PMU_EVTYPE_MASK definition has
been removed and the mask is constructed programmatically.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: James Clark <james.clark@arm.com>
---
 drivers/perf/arm_pmuv3.c       | 9 ++++++++-
 include/linux/perf/arm_pmuv3.h | 3 ++-
 2 files changed, 10 insertions(+), 2 deletions(-)

Comments

Uwe Kleine-König Dec. 15, 2023, 12:08 p.m. UTC | #1 
Hello,

On Mon, Dec 11, 2023 at 04:13:17PM +0000, James Clark wrote:
> FEAT_PMUv3_TH (Armv8.8) adds two new fields to PMEVTYPER, so include
> them in the mask. These aren't writable on 32 bit kernels as they are in
> the high part of the register, so only include them for arm64.
> 
> It would be difficult to do this statically in the asm header files for
> each platform without resulting in circular includes or #ifdefs inline
> in the code. For that reason the ARMV8_PMU_EVTYPE_MASK definition has
> been removed and the mask is constructed programmatically.
> 
> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
> Signed-off-by: James Clark <james.clark@arm.com>

This change is in today's next as commit
3115ee021bfb04efde2e96507bfcc1330261a6a1. this breaks allmodconfig
building on ARCH=arm:

	In file included from include/linux/ratelimit_types.h:5,
			 from include/linux/printk.h:9,
			 from include/asm-generic/bug.h:22,
			 from arch/arm/include/asm/bug.h:60,
			 from include/linux/bug.h:5,
			 from include/linux/mmdebug.h:5,
			 from include/linux/percpu.h:5,
			 from include/asm-generic/irq_regs.h:11,
			 from ./arch/arm/include/generated/asm/irq_regs.h:1,
			 from drivers/perf/arm_pmuv3.c:11:
	drivers/perf/arm_pmuv3.c: In function ‘armv8pmu_write_evtype’:
	include/linux/bits.h:34:29: error: left shift count >= width of type [-Werror=shift-count-overflow]
	   34 |         (((~UL(0)) - (UL(1) << (l)) + 1) & \
	      |                             ^~
	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
	      |                                      ^~~~~~~~~
	include/linux/perf/arm_pmuv3.h:238:33: note: in expansion of macro ‘GENMASK’
	  238 | #define ARMV8_PMU_EVTYPE_TC     GENMASK(63, 61)
	      |                                 ^~~~~~~
	drivers/perf/arm_pmuv3.c:567:25: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TC’
	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
	      |                         ^~~~~~~~~~~~~~~~~~~
	include/linux/bits.h:35:18: error: right shift count is negative [-Werror=shift-count-negative]
	   35 |          (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
	      |                  ^~
	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
	      |                                      ^~~~~~~~~
	include/linux/perf/arm_pmuv3.h:238:33: note: in expansion of macro ‘GENMASK’
	  238 | #define ARMV8_PMU_EVTYPE_TC     GENMASK(63, 61)
	      |                                 ^~~~~~~
	drivers/perf/arm_pmuv3.c:567:25: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TC’
	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
	      |                         ^~~~~~~~~~~~~~~~~~~
	include/linux/bits.h:34:29: error: left shift count >= width of type [-Werror=shift-count-overflow]
	   34 |         (((~UL(0)) - (UL(1) << (l)) + 1) & \
	      |                             ^~
	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
	      |                                      ^~~~~~~~~
	include/linux/perf/arm_pmuv3.h:237:33: note: in expansion of macro ‘GENMASK’
	  237 | #define ARMV8_PMU_EVTYPE_TH     GENMASK(43, 32)
	      |                                 ^~~~~~~
	drivers/perf/arm_pmuv3.c:567:47: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TH’
	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
	      |                                               ^~~~~~~~~~~~~~~~~~~
	include/linux/bits.h:35:18: error: right shift count is negative [-Werror=shift-count-negative]
	   35 |          (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
	      |                  ^~
	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
	      |                                      ^~~~~~~~~
	include/linux/perf/arm_pmuv3.h:237:33: note: in expansion of macro ‘GENMASK’
	  237 | #define ARMV8_PMU_EVTYPE_TH     GENMASK(43, 32)
	      |                                 ^~~~~~~
	drivers/perf/arm_pmuv3.c:567:47: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TH’
	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
	      |                                               ^~~~~~~~~~~~~~~~~~~

I guess that's easy to fix but I didn't look into that.

Best regards
Uwe
James Clark Dec. 15, 2023, 12:43 p.m. UTC | #2 
On 15/12/2023 12:08, Uwe Kleine-König wrote:
> Hello,
> 
> On Mon, Dec 11, 2023 at 04:13:17PM +0000, James Clark wrote:
>> FEAT_PMUv3_TH (Armv8.8) adds two new fields to PMEVTYPER, so include
>> them in the mask. These aren't writable on 32 bit kernels as they are in
>> the high part of the register, so only include them for arm64.
>>
>> It would be difficult to do this statically in the asm header files for
>> each platform without resulting in circular includes or #ifdefs inline
>> in the code. For that reason the ARMV8_PMU_EVTYPE_MASK definition has
>> been removed and the mask is constructed programmatically.
>>
>> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
>> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
>> Signed-off-by: James Clark <james.clark@arm.com>
> 
> This change is in today's next as commit
> 3115ee021bfb04efde2e96507bfcc1330261a6a1. this breaks allmodconfig
> building on ARCH=arm:
> 
> 	In file included from include/linux/ratelimit_types.h:5,
> 			 from include/linux/printk.h:9,
> 			 from include/asm-generic/bug.h:22,
> 			 from arch/arm/include/asm/bug.h:60,
> 			 from include/linux/bug.h:5,
> 			 from include/linux/mmdebug.h:5,
> 			 from include/linux/percpu.h:5,
> 			 from include/asm-generic/irq_regs.h:11,
> 			 from ./arch/arm/include/generated/asm/irq_regs.h:1,
> 			 from drivers/perf/arm_pmuv3.c:11:
> 	drivers/perf/arm_pmuv3.c: In function ‘armv8pmu_write_evtype’:
> 	include/linux/bits.h:34:29: error: left shift count >= width of type [-Werror=shift-count-overflow]
> 	   34 |         (((~UL(0)) - (UL(1) << (l)) + 1) & \
> 	      |                             ^~
> 	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
> 	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
> 	      |                                      ^~~~~~~~~
> 	include/linux/perf/arm_pmuv3.h:238:33: note: in expansion of macro ‘GENMASK’
> 	  238 | #define ARMV8_PMU_EVTYPE_TC     GENMASK(63, 61)
> 	      |                                 ^~~~~~~
> 	drivers/perf/arm_pmuv3.c:567:25: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TC’
> 	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
> 	      |                         ^~~~~~~~~~~~~~~~~~~
> 	include/linux/bits.h:35:18: error: right shift count is negative [-Werror=shift-count-negative]
> 	   35 |          (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
> 	      |                  ^~
> 	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
> 	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
> 	      |                                      ^~~~~~~~~
> 	include/linux/perf/arm_pmuv3.h:238:33: note: in expansion of macro ‘GENMASK’
> 	  238 | #define ARMV8_PMU_EVTYPE_TC     GENMASK(63, 61)
> 	      |                                 ^~~~~~~
> 	drivers/perf/arm_pmuv3.c:567:25: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TC’
> 	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
> 	      |                         ^~~~~~~~~~~~~~~~~~~
> 	include/linux/bits.h:34:29: error: left shift count >= width of type [-Werror=shift-count-overflow]
> 	   34 |         (((~UL(0)) - (UL(1) << (l)) + 1) & \
> 	      |                             ^~
> 	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
> 	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
> 	      |                                      ^~~~~~~~~
> 	include/linux/perf/arm_pmuv3.h:237:33: note: in expansion of macro ‘GENMASK’
> 	  237 | #define ARMV8_PMU_EVTYPE_TH     GENMASK(43, 32)
> 	      |                                 ^~~~~~~
> 	drivers/perf/arm_pmuv3.c:567:47: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TH’
> 	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
> 	      |                                               ^~~~~~~~~~~~~~~~~~~
> 	include/linux/bits.h:35:18: error: right shift count is negative [-Werror=shift-count-negative]
> 	   35 |          (~UL(0) >> (BITS_PER_LONG - 1 - (h))))
> 	      |                  ^~
> 	include/linux/bits.h:37:38: note: in expansion of macro ‘__GENMASK’
> 	   37 |         (GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
> 	      |                                      ^~~~~~~~~
> 	include/linux/perf/arm_pmuv3.h:237:33: note: in expansion of macro ‘GENMASK’
> 	  237 | #define ARMV8_PMU_EVTYPE_TH     GENMASK(43, 32)
> 	      |                                 ^~~~~~~
> 	drivers/perf/arm_pmuv3.c:567:47: note: in expansion of macro ‘ARMV8_PMU_EVTYPE_TH’
> 	  567 |                 mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
> 	      |                                               ^~~~~~~~~~~~~~~~~~~
> 
> I guess that's easy to fix but I didn't look into that.
> 
> Best regards
> Uwe
> 

Thanks for the report. I see that the build is only broken with GCC and
is working with LLVM. I will look into a fix.

Worst case the if can be changed to an #ifdef

James
diff mbox series

Patch

diff --git a/drivers/perf/arm_pmuv3.c b/drivers/perf/arm_pmuv3.c
index fbdf3cab8e66..16ef8448afc0 100644
--- a/drivers/perf/arm_pmuv3.c
+++ b/drivers/perf/arm_pmuv3.c
@@ -554,8 +554,15 @@  static void armv8pmu_write_counter(struct perf_event *event, u64 value)
 static void armv8pmu_write_evtype(int idx, u32 val)
 {
 	u32 counter = ARMV8_IDX_TO_COUNTER(idx);
+	unsigned long mask = ARMV8_PMU_EVTYPE_EVENT |
+			     ARMV8_PMU_INCLUDE_EL2 |
+			     ARMV8_PMU_EXCLUDE_EL0 |
+			     ARMV8_PMU_EXCLUDE_EL1;
 
-	val &= ARMV8_PMU_EVTYPE_MASK;
+	if (IS_ENABLED(CONFIG_ARM64))
+		mask |= ARMV8_PMU_EVTYPE_TC | ARMV8_PMU_EVTYPE_TH;
+
+	val &= mask;
 	write_pmevtypern(counter, val);
 }
 
diff --git a/include/linux/perf/arm_pmuv3.h b/include/linux/perf/arm_pmuv3.h
index daa63542242d..91957b3468e9 100644
--- a/include/linux/perf/arm_pmuv3.h
+++ b/include/linux/perf/arm_pmuv3.h
@@ -233,8 +233,9 @@ 
 /*
  * PMXEVTYPER: Event selection reg
  */
-#define ARMV8_PMU_EVTYPE_MASK	0xc800ffff	/* Mask for writable bits */
 #define ARMV8_PMU_EVTYPE_EVENT	GENMASK(15, 0)	/* Mask for EVENT bits */
+#define ARMV8_PMU_EVTYPE_TH	GENMASK(43, 32)
+#define ARMV8_PMU_EVTYPE_TC	GENMASK(63, 61)
 
 /*
  * Event filters for PMUv3