1. 01 5月, 2013 2 次提交
  2. 12 4月, 2013 1 次提交
    • J
      vhost_net: remove tx polling state · 70181d51
      Jason Wang 提交于
      After commit 2b8b328b (vhost_net: handle polling
      errors when setting backend), we in fact track the polling state through
      poll->wqh, so there's no need to duplicate the work with an extra
      vhost_net_polling_state. So this patch removes this and make the code simpler.
      
      This patch also removes the all tx starting/stopping code in tx path according
      to Michael's suggestion.
      
      Netperf test shows almost the same result in stream test, but gets improvements
      on TCP_RR tests (both zerocopy or copy) especially on low load cases.
      
      Tested between multiqueue kvm guest and external host with two direct
      connected 82599s.
      
      zerocopy disabled:
      
      sessions|transaction rates|normalize|
      before/after/+improvements
      1 | 9510.24/11727.29/+23.3%    | 693.54/887.68/+28.0%   |
      25| 192931.50/241729.87/+25.3% | 2376.80/2771.70/+16.6% |
      50| 277634.64/291905.76/+5%    | 3118.36/3230.11/+3.6%  |
      
      zerocopy enabled:
      
      sessions|transaction rates|normalize|
      before/after/+improvements
      1 | 7318.33/11929.76/+63.0%    | 521.86/843.30/+61.6%   |
      25| 167264.88/242422.15/+44.9% | 2181.60/2788.16/+27.8% |
      50| 272181.02/294347.04/+8.1%  | 3071.56/3257.85/+6.1%  |
      Signed-off-by: NJason Wang <jasowang@redhat.com>
      Acked-by: NMichael S. Tsirkin <mst@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      70181d51
  3. 18 3月, 2013 1 次提交
  4. 30 1月, 2013 2 次提交
  5. 06 12月, 2012 4 次提交
  6. 04 12月, 2012 1 次提交
  7. 03 11月, 2012 4 次提交
  8. 25 10月, 2012 1 次提交
  9. 22 7月, 2012 1 次提交
  10. 12 5月, 2012 1 次提交
  11. 02 5月, 2012 3 次提交
  12. 14 4月, 2012 1 次提交
  13. 28 2月, 2012 1 次提交
  14. 14 1月, 2012 1 次提交
  15. 21 7月, 2011 2 次提交
  16. 19 7月, 2011 2 次提交
    • J
      vhost: init used ring after backend was set · f59281da
      Jason Wang 提交于
      Move the used ring initialization after backend was set. This
      makes it possible to disable the backend and tweak the used ring,
      then restart. This will also make it possible to log the used ring
      write correctly.
      Signed-off-by: NJason Wang <jasowang@redhat.com>
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      f59281da
    • M
      vhost: vhost TX zero-copy support · bab632d6
      Michael S. Tsirkin 提交于
      >From: Shirley Ma <mashirle@us.ibm.com>
      
      This adds experimental zero copy support in vhost-net,
      disabled by default. To enable, set
      experimental_zcopytx module option to 1.
      
      This patch maintains the outstanding userspace buffers in the
      sequence it is delivered to vhost. The outstanding userspace buffers
      will be marked as done once the lower device buffers DMA has finished.
      This is monitored through last reference of kfree_skb callback. Two
      buffer indices are used for this purpose.
      
      The vhost-net device passes the userspace buffers info to lower device
      skb through message control. DMA done status check and guest
      notification are handled by handle_tx: in the worst case is all buffers
      in the vq are in pending/done status, so we need to notify guest to
      release DMA done buffers first before we get any new buffers from the
      vq.
      
      One known problem is that if the guest stops submitting
      buffers, buffers might never get used until some
      further action, e.g. device reset. This does not
      seem to affect linux guests.
      Signed-off-by: NShirley <xma@us.ibm.com>
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      bab632d6
  17. 30 5月, 2011 1 次提交
  18. 14 3月, 2011 2 次提交
  19. 13 3月, 2011 2 次提交
  20. 09 3月, 2011 1 次提交
  21. 01 2月, 2011 1 次提交
    • M
      vhost: rcu annotation fixup · 5e18247b
      Michael S. Tsirkin 提交于
      When built with rcu checks enabled, vhost triggers
      bogus warnings as vhost features are read without
      dev->mutex sometimes, and private pointer is read
      with our kind of rcu where work serves as a
      read side critical section.
      
      Fixing it properly is not trivial.
      Disable the warnings by stubbing out the checks for now.
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      5e18247b
  22. 09 12月, 2010 1 次提交
  23. 25 11月, 2010 1 次提交
  24. 04 11月, 2010 1 次提交
  25. 15 10月, 2010 1 次提交
    • A
      llseek: automatically add .llseek fop · 6038f373
      Arnd Bergmann 提交于
      All file_operations should get a .llseek operation so we can make
      nonseekable_open the default for future file operations without a
      .llseek pointer.
      
      The three cases that we can automatically detect are no_llseek, seq_lseek
      and default_llseek. For cases where we can we can automatically prove that
      the file offset is always ignored, we use noop_llseek, which maintains
      the current behavior of not returning an error from a seek.
      
      New drivers should normally not use noop_llseek but instead use no_llseek
      and call nonseekable_open at open time.  Existing drivers can be converted
      to do the same when the maintainer knows for certain that no user code
      relies on calling seek on the device file.
      
      The generated code is often incorrectly indented and right now contains
      comments that clarify for each added line why a specific variant was
      chosen. In the version that gets submitted upstream, the comments will
      be gone and I will manually fix the indentation, because there does not
      seem to be a way to do that using coccinelle.
      
      Some amount of new code is currently sitting in linux-next that should get
      the same modifications, which I will do at the end of the merge window.
      
      Many thanks to Julia Lawall for helping me learn to write a semantic
      patch that does all this.
      
      ===== begin semantic patch =====
      // This adds an llseek= method to all file operations,
      // as a preparation for making no_llseek the default.
      //
      // The rules are
      // - use no_llseek explicitly if we do nonseekable_open
      // - use seq_lseek for sequential files
      // - use default_llseek if we know we access f_pos
      // - use noop_llseek if we know we don't access f_pos,
      //   but we still want to allow users to call lseek
      //
      @ open1 exists @
      identifier nested_open;
      @@
      nested_open(...)
      {
      <+...
      nonseekable_open(...)
      ...+>
      }
      
      @ open exists@
      identifier open_f;
      identifier i, f;
      identifier open1.nested_open;
      @@
      int open_f(struct inode *i, struct file *f)
      {
      <+...
      (
      nonseekable_open(...)
      |
      nested_open(...)
      )
      ...+>
      }
      
      @ read disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      <+...
      (
         *off = E
      |
         *off += E
      |
         func(..., off, ...)
      |
         E = *off
      )
      ...+>
      }
      
      @ read_no_fpos disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ write @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      <+...
      (
        *off = E
      |
        *off += E
      |
        func(..., off, ...)
      |
        E = *off
      )
      ...+>
      }
      
      @ write_no_fpos @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ fops0 @
      identifier fops;
      @@
      struct file_operations fops = {
       ...
      };
      
      @ has_llseek depends on fops0 @
      identifier fops0.fops;
      identifier llseek_f;
      @@
      struct file_operations fops = {
      ...
       .llseek = llseek_f,
      ...
      };
      
      @ has_read depends on fops0 @
      identifier fops0.fops;
      identifier read_f;
      @@
      struct file_operations fops = {
      ...
       .read = read_f,
      ...
      };
      
      @ has_write depends on fops0 @
      identifier fops0.fops;
      identifier write_f;
      @@
      struct file_operations fops = {
      ...
       .write = write_f,
      ...
      };
      
      @ has_open depends on fops0 @
      identifier fops0.fops;
      identifier open_f;
      @@
      struct file_operations fops = {
      ...
       .open = open_f,
      ...
      };
      
      // use no_llseek if we call nonseekable_open
      ////////////////////////////////////////////
      @ nonseekable1 depends on !has_llseek && has_open @
      identifier fops0.fops;
      identifier nso ~= "nonseekable_open";
      @@
      struct file_operations fops = {
      ...  .open = nso, ...
      +.llseek = no_llseek, /* nonseekable */
      };
      
      @ nonseekable2 depends on !has_llseek @
      identifier fops0.fops;
      identifier open.open_f;
      @@
      struct file_operations fops = {
      ...  .open = open_f, ...
      +.llseek = no_llseek, /* open uses nonseekable */
      };
      
      // use seq_lseek for sequential files
      /////////////////////////////////////
      @ seq depends on !has_llseek @
      identifier fops0.fops;
      identifier sr ~= "seq_read";
      @@
      struct file_operations fops = {
      ...  .read = sr, ...
      +.llseek = seq_lseek, /* we have seq_read */
      };
      
      // use default_llseek if there is a readdir
      ///////////////////////////////////////////
      @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier readdir_e;
      @@
      // any other fop is used that changes pos
      struct file_operations fops = {
      ... .readdir = readdir_e, ...
      +.llseek = default_llseek, /* readdir is present */
      };
      
      // use default_llseek if at least one of read/write touches f_pos
      /////////////////////////////////////////////////////////////////
      @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read.read_f;
      @@
      // read fops use offset
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = default_llseek, /* read accesses f_pos */
      };
      
      @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ... .write = write_f, ...
      +	.llseek = default_llseek, /* write accesses f_pos */
      };
      
      // Use noop_llseek if neither read nor write accesses f_pos
      ///////////////////////////////////////////////////////////
      
      @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      identifier write_no_fpos.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ...
       .write = write_f,
       .read = read_f,
      ...
      +.llseek = noop_llseek, /* read and write both use no f_pos */
      };
      
      @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write_no_fpos.write_f;
      @@
      struct file_operations fops = {
      ... .write = write_f, ...
      +.llseek = noop_llseek, /* write uses no f_pos */
      };
      
      @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      @@
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = noop_llseek, /* read uses no f_pos */
      };
      
      @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      @@
      struct file_operations fops = {
      ...
      +.llseek = noop_llseek, /* no read or write fn */
      };
      ===== End semantic patch =====
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Julia Lawall <julia@diku.dk>
      Cc: Christoph Hellwig <hch@infradead.org>
      6038f373
  26. 05 10月, 2010 1 次提交
    • J
      vhost: max s/g to match qemu · e0e9b406
      Jason Wang 提交于
      Qemu supports up to UIO_MAXIOV s/g so we have to match that because guest
      drivers may rely on this.
      
      Allocate indirect and log arrays dynamically to avoid using too much contigious
      memory and make the length of hdr array to match the header length since each
      iovec entry has a least one byte.
      
      Test with copying large files w/ and w/o migration in both linux and windows
      guests.
      Signed-off-by: NJason Wang <jasowang@redhat.com>
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      e0e9b406