diff mbox series

[v3,3/7] powerpc/pmem: Add flush routines using new pmem store and sync instruction

Message ID 20200519055502.128318-3-aneesh.kumar@linux.ibm.com
State New
Headers show
Series [v3,1/7] powerpc/pmem: Restrict papr_scm to P8 and above. | expand

Checks

Context Check Description
snowpatch_ozlabs/needsstable success Patch has no Fixes tags
snowpatch_ozlabs/checkpatch warning total: 6 errors, 1 warnings, 4 checks, 80 lines checked
snowpatch_ozlabs/apply_patch success Successfully applied on branch powerpc/merge (7b06fb8795ffea9d12be45a172197c3307955479)

Commit Message

Aneesh Kumar K.V May 19, 2020, 5:54 a.m. UTC
Start using dcbstps; phwsync; sequence for flushing persistent memory range.
The new instructions are implemented as a variant of dcbf and hwsync and on
P8 and P9 they will be executed as those instructions. We avoid using them on
older hardware. This helps to avoid difficult to debug bugs.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
---
 arch/powerpc/lib/pmem.c | 50 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 46 insertions(+), 4 deletions(-)

Comments

kbuild test robot May 30, 2020, 12:47 a.m. UTC | #1
Hi "Aneesh,

I love your patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on v5.7-rc7 next-20200529]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Aneesh-Kumar-K-V/powerpc-pmem-Restrict-papr_scm-to-P8-and-above/20200519-195350
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-randconfig-r016-20200529 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 2d068e534f1671459e1b135852c1b3c10502e929)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install powerpc cross compiling tool for clang build
        # apt-get install binutils-powerpc-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> arch/powerpc/lib/pmem.c:44:6: error: implicit declaration of function 'cpu_has_feature' [-Werror,-Wimplicit-function-declaration]
if (cpu_has_feature(CPU_FTR_ARCH_207S))
^
arch/powerpc/lib/pmem.c:44:6: note: did you mean 'mmu_has_feature'?
arch/powerpc/include/asm/mmu.h:234:20: note: 'mmu_has_feature' declared here
static inline bool mmu_has_feature(unsigned long feature)
^
arch/powerpc/lib/pmem.c:50:6: error: implicit declaration of function 'cpu_has_feature' [-Werror,-Wimplicit-function-declaration]
if (cpu_has_feature(CPU_FTR_ARCH_207S))
^
arch/powerpc/lib/pmem.c:57:6: warning: no previous prototype for function 'arch_wb_cache_pmem' [-Wmissing-prototypes]
void arch_wb_cache_pmem(void *addr, size_t size)
^
arch/powerpc/lib/pmem.c:57:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void arch_wb_cache_pmem(void *addr, size_t size)
^
static
arch/powerpc/lib/pmem.c:64:6: warning: no previous prototype for function 'arch_invalidate_pmem' [-Wmissing-prototypes]
void arch_invalidate_pmem(void *addr, size_t size)
^
arch/powerpc/lib/pmem.c:64:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
void arch_invalidate_pmem(void *addr, size_t size)
^
static
2 warnings and 2 errors generated.

vim +/cpu_has_feature +44 arch/powerpc/lib/pmem.c

    41	
    42	static inline void clean_pmem_range(unsigned long start, unsigned long stop)
    43	{
  > 44		if (cpu_has_feature(CPU_FTR_ARCH_207S))
    45			return __clean_pmem_range(start, stop);
    46	}
    47	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/arch/powerpc/lib/pmem.c b/arch/powerpc/lib/pmem.c
index 0666a8d29596..5a61aaeb6930 100644
--- a/arch/powerpc/lib/pmem.c
+++ b/arch/powerpc/lib/pmem.c
@@ -9,20 +9,62 @@ 
 
 #include <asm/cacheflush.h>
 
+static inline void __clean_pmem_range(unsigned long start, unsigned long stop)
+{
+	unsigned long shift = l1_dcache_shift();
+	unsigned long bytes = l1_dcache_bytes();
+	void *addr = (void *)(start & ~(bytes - 1));
+	unsigned long size = stop - (unsigned long)addr + (bytes - 1);
+	unsigned long i;
+
+	for (i = 0; i < size >> shift; i++, addr += bytes)
+		asm volatile(PPC_DCBSTPS(%0, %1): :"i"(0), "r"(addr): "memory");
+
+
+	asm volatile(PPC_PHWSYNC ::: "memory");
+}
+
+static inline void __flush_pmem_range(unsigned long start, unsigned long stop)
+{
+	unsigned long shift = l1_dcache_shift();
+	unsigned long bytes = l1_dcache_bytes();
+	void *addr = (void *)(start & ~(bytes - 1));
+	unsigned long size = stop - (unsigned long)addr + (bytes - 1);
+	unsigned long i;
+
+	for (i = 0; i < size >> shift; i++, addr += bytes)
+		asm volatile(PPC_DCBFPS(%0, %1): :"i"(0), "r"(addr): "memory");
+
+
+	asm volatile(PPC_PHWSYNC ::: "memory");
+}
+
+static inline void clean_pmem_range(unsigned long start, unsigned long stop)
+{
+	if (cpu_has_feature(CPU_FTR_ARCH_207S))
+		return __clean_pmem_range(start, stop);
+}
+
+static inline void flush_pmem_range(unsigned long start, unsigned long stop)
+{
+	if (cpu_has_feature(CPU_FTR_ARCH_207S))
+		return __flush_pmem_range(start, stop);
+}
+
 /*
  * CONFIG_ARCH_HAS_PMEM_API symbols
  */
 void arch_wb_cache_pmem(void *addr, size_t size)
 {
 	unsigned long start = (unsigned long) addr;
-	flush_dcache_range(start, start + size);
+	clean_pmem_range(start, start + size);
 }
 EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
 
 void arch_invalidate_pmem(void *addr, size_t size)
 {
 	unsigned long start = (unsigned long) addr;
-	flush_dcache_range(start, start + size);
+	flush_pmem_range(start, start + size);
 }
 EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
 
@@ -35,7 +77,7 @@  long __copy_from_user_flushcache(void *dest, const void __user *src,
 	unsigned long copied, start = (unsigned long) dest;
 
 	copied = __copy_from_user(dest, src, size);
-	flush_dcache_range(start, start + size);
+	clean_pmem_range(start, start + size);
 
 	return copied;
 }
@@ -45,7 +87,7 @@  void *memcpy_flushcache(void *dest, const void *src, size_t size)
 	unsigned long start = (unsigned long) dest;
 
 	memcpy(dest, src, size);
-	flush_dcache_range(start, start + size);
+	clean_pmem_range(start, start + size);
 
 	return dest;
 }