#
ce5e4803 |
|
26-Oct-2021 |
王贇 <yun.wang@linux.alibaba.com> |
ftrace: disable preemption when recursion locked As the documentation explained, ftrace_test_recursion_trylock() and ftrace_test_recursion_unlock() were supposed to disable and enable preemption properly, however currently this work is done outside of the function, which could be missing by mistake. And since the internal using of trace_test_and_set_recursion() and trace_clear_recursion() also require preemption disabled, we can just merge the logical. This patch will make sure the preemption has been disabled when trace_test_and_set_recursion() return bit >= 0, and trace_clear_recursion() will enable the preemption if previously enabled. Link: https://lkml.kernel.org/r/13bde807-779c-aa4c-0672-20515ae365ea@linux.alibaba.com CC: Petr Mladek <pmladek@suse.com> Cc: Guo Ren <guoren@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Helge Deller <deller@gmx.de> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Jisheng Zhang <jszhang@kernel.org> CC: Steven Rostedt <rostedt@goodmis.org> CC: Miroslav Benes <mbenes@suse.cz> Reported-by: Abaci <abaci@linux.alibaba.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com> [ Removed extra line in comment - SDR ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
#
e0196ae7 |
|
11-Mar-2021 |
Colin Ian King <colin.king@canonical.com> |
ftrace: Fix spelling mistake "disabed" -> "disabled" There is a spelling mistake in a comment, fix it. Link: https://lkml.kernel.org/r/20210311094022.5978-1-colin.king@canonical.com Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
#
e31be8d3 |
|
29-Mar-2021 |
Jisheng Zhang <jszhang@kernel.org> |
riscv: kprobes/ftrace: Add recursion protection to the ftrace callback Currently, the riscv's kprobes(powerred by ftrace) handler is preemptible. Futher check indicates we miss something similar as the commit c536aa1c5b17 ("kprobes/ftrace: Add recursion protection to the ftrace callback"), so do similar modifications as the commit does. Fixes: 829adda597fe ("riscv: Add KPROBES_ON_FTRACE supported") Cc: stable@vger.kernel.org Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
|
#
bab1770a |
|
11-Mar-2021 |
Colin Ian King <colin.king@canonical.com> |
ftrace: Fix spelling mistake "disabed" -> "disabled" There is a spelling mistake in a comment, fix it. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
|
#
288f6775 |
|
05-Mar-2021 |
Nanyong Sun <sunnanyong@huawei.com> |
riscv: ftrace: Use ftrace_get_regs helper Use ftrace_get_regs() helper call to get pt_regs from ftrace_regs struct, this makes the code simpler. Signed-off-by: Nanyong Sun <sunnanyong@huawei.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
|
#
829adda5 |
|
17-Dec-2020 |
Guo Ren <guoren@linux.alibaba.com> |
riscv: Add KPROBES_ON_FTRACE supported This patch adds support for kprobes on ftrace call sites to avoids much of the overhead with regular kprobes. Try it with simple steps: echo 'p:myprobe sys_clone a0=%a0 a1=%a1 stack_val=+4($stack)' > /sys/kernel/de bug/tracing/kprobe_events echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable cat /sys/kernel/debug/tracing/trace tracer: nop entries-in-buffer/entries-written: 1/1 #P:1 _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID CPU# |||| TIMESTAMP FUNCTION | | | |||| | | sh-92 [000] .... 369.899962: myprobe: (sys_clone+0x0/0x28) a0=0x1200011 a1=0x0 stack_val=0x201c20ffffffe0 cat /sys/kernel/debug/kprobes/list ffffffe00020b584 k sys_clone+0x0 [FTRACE] ^^^^^^ Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
|