On 2024-10-04 03:11, Mathieu Desnoyers wrote:
Wire up the system call tracepoints with Tasks Trace RCU to allow
the ftrace, perf, and eBPF tracers to handle page faults.
This series does the initial wire-up allowing tracers to handle page
faults, but leaves out the actual handling of said page faults as future
work.
This series was compile and runtime tested with ftrace and perf syscall
tracing and raw syscall tracing, adding a WARN_ON_ONCE() in the
generated code to validate that the intended probes are used for raw
syscall tracing. The might_fault() added within those probes validate
that they are called from a context where handling a page fault is OK.
This series replaces the "Faultable Tracepoints v6" series found at [1].
This has been rebased on v6.12-rc1 on top of two patches from Steven:
tracing: Remove definition of trace_*_rcuidle()
tracepoint: Remove SRCU protection
I'll send an updated series which includes
"tracing: Declare system call tracepoints with TRACE_EVENT_SYSCALL"
(missing here), and which rework that patch to remove the mapping from
trace_sys_enter/exit to trace_syscall_sys_enter/exit which requires
modifying architecture code. A lot of churn for little value add.
Thanks,
Mathieu
Thanks,
Mathieu
Link:
https://lore.kernel.org/lkml/[email protected]/
# [1]
Cc: Peter Zijlstra <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Yonghong Song <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: [email protected]
Cc: Joel Fernandes <[email protected]>
Cc: [email protected]
Mathieu Desnoyers (7):
tracing/ftrace: guard syscall probe with preempt_notrace
tracing/perf: guard syscall probe with preempt_notrace
tracing/bpf: guard syscall probe with preempt_notrace
tracing: Allow system call tracepoints to handle page faults
tracing/ftrace: Add might_fault check to syscall probes
tracing/perf: Add might_fault check to syscall probes
tracing/bpf: Add might_fault check to syscall probes
include/linux/tracepoint.h | 18 ++++++++++-----
include/trace/bpf_probe.h | 12 +++++++++-
include/trace/perf.h | 42 +++++++++++++++++++++++++++++++----
include/trace/trace_events.h | 39 ++++++++++++++++++++++++++------
init/Kconfig | 1 +
kernel/trace/trace_syscalls.c | 28 +++++++++++++++++++++++
6 files changed, 123 insertions(+), 17 deletions(-)
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
