prefect(page) is a common thing to be called from drivers. Add
netmem_prefetch that can be called on generic netmem. Skips the prefetch
for net_iovs.
Signed-off-by: Mina Almasry <almasrymina@google.com>
---
include/net/netmem.h | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/include/net/netmem.h b/include/net/netmem.h
index 8a6e20be4b9d..923c47147aa8 100644
--- a/include/net/netmem.h
+++ b/include/net/netmem.h
@@ -171,4 +171,11 @@ static inline unsigned long netmem_get_dma_addr(netmem_ref netmem)
return __netmem_clear_lsb(netmem)->dma_addr;
}
+static inline void netmem_prefetch(netmem_ref netmem)
+{
+ if (netmem_is_net_iov(netmem))
+ return;
+
+ prefetch(netmem_to_page(netmem));
+}
#endif /* _NET_NETMEM_H */
--
2.47.0.277.g8800431eea-goog
On Thu, 7 Nov 2024 21:23:09 +0000 Mina Almasry wrote: > prefect(page) is a common thing to be called from drivers. Add > netmem_prefetch that can be called on generic netmem. Skips the prefetch > for net_iovs. Why would you ever need to prefetch a payload buffer? Looks wrong..
On 11/07, Mina Almasry wrote: > prefect(page) is a common thing to be called from drivers. Add > netmem_prefetch that can be called on generic netmem. Skips the prefetch > for net_iovs. > > Signed-off-by: Mina Almasry <almasrymina@google.com> Needs some extra includes to make the build bot happy, after that: Acked-by: Stanislav Fomichev <sdf@fomichev.me> --- pw-bot: cr
Hi Mina,
kernel test robot noticed the following build errors:
[auto build test ERROR on net-next/main]
url: https://github.com/intel-lab-lkp/linux/commits/Mina-Almasry/net-page_pool-rename-page_pool_alloc_netmem-to-_netmems/20241108-052530
base: net-next/main
patch link: https://lore.kernel.org/r/20241107212309.3097362-6-almasrymina%40google.com
patch subject: [PATCH net-next v2 5/5] netmem: add netmem_prefetch
config: s390-allyesconfig (https://download.01.org/0day-ci/archive/20241108/202411081130.CxioaC2A-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241108/202411081130.CxioaC2A-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411081130.CxioaC2A-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from include/linux/skbuff.h:40,
from include/linux/if_ether.h:19,
from arch/s390/include/asm/diag.h:12,
from arch/s390/include/asm/kvm_para.h:25,
from include/uapi/linux/kvm_para.h:37,
from include/linux/kvm_para.h:5,
from include/linux/kvm_host.h:41,
from arch/s390/kernel/asm-offsets.c:11:
include/net/netmem.h: In function 'netmem_prefetch':
>> include/net/netmem.h:179:9: error: implicit declaration of function 'prefetch' [-Wimplicit-function-declaration]
179 | prefetch(netmem_to_page(netmem));
| ^~~~~~~~
make[3]: *** [scripts/Makefile.build:102: arch/s390/kernel/asm-offsets.s] Error 1
make[3]: Target 'prepare' not remade because of errors.
make[2]: *** [Makefile:1203: prepare0] Error 2
make[2]: Target 'prepare' not remade because of errors.
make[1]: *** [Makefile:224: __sub-make] Error 2
make[1]: Target 'prepare' not remade because of errors.
make: *** [Makefile:224: __sub-make] Error 2
make: Target 'prepare' not remade because of errors.
vim +/prefetch +179 include/net/netmem.h
173
174 static inline void netmem_prefetch(netmem_ref netmem)
175 {
176 if (netmem_is_net_iov(netmem))
177 return;
178
> 179 prefetch(netmem_to_page(netmem));
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Mina,
kernel test robot noticed the following build errors:
[auto build test ERROR on net-next/main]
url: https://github.com/intel-lab-lkp/linux/commits/Mina-Almasry/net-page_pool-rename-page_pool_alloc_netmem-to-_netmems/20241108-052530
base: net-next/main
patch link: https://lore.kernel.org/r/20241107212309.3097362-6-almasrymina%40google.com
patch subject: [PATCH net-next v2 5/5] netmem: add netmem_prefetch
config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20241108/202411081105.Z1kEMaBE-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 592c0fe55f6d9a811028b5f3507be91458ab2713)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241108/202411081105.Z1kEMaBE-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411081105.Z1kEMaBE-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from arch/s390/kernel/asm-offsets.c:11:
In file included from include/linux/kvm_host.h:16:
In file included from include/linux/mm.h:2213:
include/linux/vmstat.h:504:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
504 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
505 | item];
| ~~~~
include/linux/vmstat.h:511:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
511 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
512 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
include/linux/vmstat.h:524:43: warning: arithmetic between different enumeration types ('enum zone_stat_item' and 'enum numa_stat_item') [-Wenum-enum-conversion]
524 | return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~ ^
525 | NR_VM_NUMA_EVENT_ITEMS +
| ~~~~~~~~~~~~~~~~~~~~~~
In file included from arch/s390/kernel/asm-offsets.c:11:
In file included from include/linux/kvm_host.h:19:
In file included from include/linux/msi.h:24:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/s390/include/asm/io.h:95:
include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
548 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
| ^
include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16'
102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
| ^
In file included from arch/s390/kernel/asm-offsets.c:11:
In file included from include/linux/kvm_host.h:19:
In file included from include/linux/msi.h:24:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/s390/include/asm/io.h:95:
include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
| ^
include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32'
115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x))
| ^
In file included from arch/s390/kernel/asm-offsets.c:11:
In file included from include/linux/kvm_host.h:19:
In file included from include/linux/msi.h:24:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:14:
In file included from arch/s390/include/asm/io.h:95:
include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
585 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:693:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
693 | readsb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:701:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
701 | readsw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:709:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
709 | readsl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:718:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
718 | writesb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:727:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
727 | writesw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:736:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
736 | writesl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
In file included from arch/s390/kernel/asm-offsets.c:11:
In file included from include/linux/kvm_host.h:41:
In file included from include/linux/kvm_para.h:5:
In file included from include/uapi/linux/kvm_para.h:37:
In file included from arch/s390/include/asm/kvm_para.h:25:
In file included from arch/s390/include/asm/diag.h:12:
In file included from include/linux/if_ether.h:19:
In file included from include/linux/skbuff.h:40:
>> include/net/netmem.h:179:2: error: call to undeclared function 'prefetch'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
179 | prefetch(netmem_to_page(netmem));
| ^
16 warnings and 1 error generated.
make[3]: *** [scripts/Makefile.build:102: arch/s390/kernel/asm-offsets.s] Error 1
make[3]: Target 'prepare' not remade because of errors.
make[2]: *** [Makefile:1203: prepare0] Error 2
make[2]: Target 'prepare' not remade because of errors.
make[1]: *** [Makefile:224: __sub-make] Error 2
make[1]: Target 'prepare' not remade because of errors.
make: *** [Makefile:224: __sub-make] Error 2
make: Target 'prepare' not remade because of errors.
vim +/prefetch +179 include/net/netmem.h
173
174 static inline void netmem_prefetch(netmem_ref netmem)
175 {
176 if (netmem_is_net_iov(netmem))
177 return;
178
> 179 prefetch(netmem_to_page(netmem));
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Mina,
kernel test robot noticed the following build warnings:
[auto build test WARNING on net-next/main]
url: https://github.com/intel-lab-lkp/linux/commits/Mina-Almasry/net-page_pool-rename-page_pool_alloc_netmem-to-_netmems/20241108-052530
base: net-next/main
patch link: https://lore.kernel.org/r/20241107212309.3097362-6-almasrymina%40google.com
patch subject: [PATCH net-next v2 5/5] netmem: add netmem_prefetch
config: parisc-allmodconfig (https://download.01.org/0day-ci/archive/20241108/202411081014.jmz4uf6C-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241108/202411081014.jmz4uf6C-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202411081014.jmz4uf6C-lkp@intel.com/
All warnings (new ones prefixed by >>):
In file included from include/linux/skbuff.h:40,
from net/ipv4/tcp_vegas.c:37:
include/net/netmem.h: In function 'netmem_prefetch':
include/net/netmem.h:179:9: error: implicit declaration of function 'prefetch' [-Wimplicit-function-declaration]
179 | prefetch(netmem_to_page(netmem));
| ^~~~~~~~
net/ipv4/tcp_vegas.c: At top level:
>> net/ipv4/tcp_vegas.c:46:12: warning: 'gamma' defined but not used [-Wunused-variable]
46 | static int gamma = 1;
| ^~~~~
vim +/gamma +46 net/ipv4/tcp_vegas.c
7752237e9f07b3 Stephen Hemminger 2007-04-23 43
8d3a564da34e58 Doug Leith 2008-12-09 44 static int alpha = 2;
8d3a564da34e58 Doug Leith 2008-12-09 45 static int beta = 4;
8d3a564da34e58 Doug Leith 2008-12-09 @46 static int gamma = 1;
b87d8561d8667d Stephen Hemminger 2005-06-23 47
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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