https://github.com/torvalds/linux
Revision f2cbd485282014132851bf37cb2ca624a456275d authored by Davide Caratti on 20 November 2018, 21:18:44 UTC, committed by David S. Miller on 20 November 2018, 22:59:58 UTC
after 'police' configuration parameters were converted to use RCU instead of spinlock, the state variables used to compute the traffic rate (namely 'tcfp_toks', 'tcfp_ptoks' and 'tcfp_t_c') are erroneously read/updated in the traffic path without any protection. Use a dedicated spinlock to avoid race conditions on these variables, and ensure proper cache-line alignment. In this way, 'police' is still faster than what we observed when 'tcf_lock' was used in the traffic path _ i.e. reverting commit 2d550dbad83c ("net/sched: act_police: don't use spinlock in the data path"). Moreover, we preserve the throughput improvement that was obtained after 'police' started using per-cpu counters, when 'avrate' is used instead of 'rate'. Changes since v1 (thanks to Eric Dumazet): - call ktime_get_ns() before acquiring the lock in the traffic path - use a dedicated spinlock instead of tcf_lock - improve cache-line usage Fixes: 2d550dbad83c ("net/sched: act_police: don't use spinlock in the data path") Reported-and-suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com>
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Tip revision: f2cbd485282014132851bf37cb2ca624a456275d authored by Davide Caratti on 20 November 2018, 21:18:44 UTC
net/sched: act_police: fix race condition on state variables
net/sched: act_police: fix race condition on state variables
Tip revision: f2cbd48
File | Mode | Size |
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LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | -rw-r--r-- | 12.7 KB |
.cocciconfig | -rw-r--r-- | 59 bytes |
.get_maintainer.ignore | -rw-r--r-- | 31 bytes |
.gitattributes | -rw-r--r-- | 30 bytes |
.gitignore | -rw-r--r-- | 1.5 KB |
.mailmap | -rw-r--r-- | 10.5 KB |
COPYING | -rw-r--r-- | 423 bytes |
CREDITS | -rw-r--r-- | 96.5 KB |
Kbuild | -rw-r--r-- | 2.2 KB |
Kconfig | -rw-r--r-- | 563 bytes |
MAINTAINERS | -rw-r--r-- | 470.9 KB |
Makefile | -rw-r--r-- | 59.7 KB |
README | -rw-r--r-- | 727 bytes |
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