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author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2020-11-06 05:32:38 +0300 |
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committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2020-11-06 16:33:23 +0300 |
commit | da5afbeb1724609996ca7bb4fbce2cd104c95914 (patch) | |
tree | 3b0401623f109b52d7c49a2e1c0f12a3eb96f9ae /fs | |
parent | 6e4eb9cb22fc8a893cb708ed42644de5ee7c3827 (diff) | |
download | linux-da5afbeb1724609996ca7bb4fbce2cd104c95914.tar.xz |
ftrace: Optimize testing what context current is in
The preempt_count() is not a simple location in memory, it could be part of
per_cpu code or more. Each access to preempt_count(), or one of its accessor
functions (like in_interrupt()) takes several cycles. By reading
preempt_count() once, and then doing tests to find the context against the
value return is slightly faster than using in_nmi() and in_interrupt().
Link: https://lkml.kernel.org/r/20201028115612.780796355@goodmis.org
Link: https://lkml.kernel.org/r/20201106023546.558881845@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'fs')
0 files changed, 0 insertions, 0 deletions