0d89419319
When TCP_ZEROCOPY_RECEIVE operation has been added, I made the mistake of automatically un-mapping prior content before mapping new pages. This has the unfortunate effect of adding potentially long MMU operations (like TLB flushes) while socket lock is held. Using madvise(MADV_DONTNEED) right after pages has been used has two benefits : 1) This releases pages sooner, allowing pages to be recycled if they were part of a page pool in a NIC driver. 2) No more long unmap operations while preventing immediate processing of incoming packets. The cost of the added system call is small enough. Arjun will submit a kernel patch allowing to opt out from the unmap attempt in tcp_zerocopy_receive() Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Arjun Roy <arjunroy@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| accounting | ||
| arch | ||
| bootconfig | ||
| bpf | ||
| build | ||
| cgroup | ||
| debugging | ||
| edid | ||
| firewire | ||
| firmware | ||
| gpio | ||
| hv | ||
| iio | ||
| include | ||
| io_uring | ||
| kvm/kvm_stat | ||
| laptop | ||
| leds | ||
| lib | ||
| memory-model | ||
| nfsd | ||
| objtool | ||
| pci | ||
| pcmcia | ||
| perf | ||
| power | ||
| scripts | ||
| spi | ||
| testing | ||
| thermal/tmon | ||
| time | ||
| usb | ||
| virtio | ||
| vm | ||
| wmi | ||
| Makefile | ||