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Diffstat (limited to 'taia.h')

0 files changed, 0 insertions, 0 deletions

f9 (diff)

net/mlx5e: Tx, no inline copy on ConnectX-5

ConnectX-5 and later HW generations will report min inline mode == MLX5_INLINE_MODE_NONE, which means driver is not required to copy packet headers to inline fields of TX WQE. When inline is not required, vlan insertion will be handled in the TX descriptor rather than copy to inline. For LSO case driver is still required to copy headers, for the HW to duplicate on wire. This will improve CPU utilization and boost TX performance. Tested with pktgen burst single flow: CPU: Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz HCA: Mellanox Technologies MT28800 Family [ConnectX-5 Ex] Before: 15.1Mpps After: 17.2Mpps Improvement: 14% Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Reviewed-by: Tariq Toukan <tariqt@mellanox.com>

Diffstat

&id=3895dbf8985f656675b5bde610723a29cbce3fa7'>sound/soc/codecs/wm8728.h

parent	0c744ea4f77d72b3dcebb7a8f2684633ec79be88 (diff)

mnt: Protect the mountpoint hashtable with mount_lock

Protecting the mountpoint hashtable with namespace_sem was sufficient until a call to umount_mnt was added to mntput_no_expire. At which point it became possible for multiple calls of put_mountpoint on the same hash chain to happen on the same time. Kristen Johansen <kjlx@templeofstupid.com> reported: > This can cause a panic when simultaneous callers of put_mountpoint > attempt to free the same mountpoint. This occurs because some callers > hold the mount_hash_lock, while others hold the namespace lock. Some > even hold both. > > In this submitter's case, the panic manifested itself as a GP fault in > put_mountpoint() when it called hlist_del() and attempted to dereference > a m_hash.pprev that had been poisioned by another thread. Al Viro observed that the simple fix is to switch from using the namespace_sem to the mount_lock to protect the mountpoint hash table. I have taken Al's suggested patch moved put_mountpoint in pivot_root (instead of taking mount_lock an additional time), and have replaced new_mountpoint with get_mountpoint a function that does the hash table lookup and addition under the mount_lock. The introduction of get_mounptoint ensures that only the mount_lock is needed to manipulate the mountpoint hashtable. d_set_mounted is modified to only set DCACHE_MOUNTED if it is not already set. This allows get_mountpoint to use the setting of DCACHE_MOUNTED to ensure adding a struct mountpoint for a dentry happens exactly once. Cc: stable@vger.kernel.org Fixes: ce07d891a089 ("mnt: Honor MNT_LOCKED when detaching mounts") Reported-by: Krister Johansen <kjlx@templeofstupid.com> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Diffstat (limited to 'sound/soc/codecs/wm8728.h')


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