Currently, the log-level of show_stack() depends on a platform
realization. It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).
Furthermore, it forces the logic decision from user to an architecture
side. In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages. And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.
Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers. Also, it will consolidate
printings with headers.
Introduce show_stack_loglvl(), that eventually will substitute
show_stack().
[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-28-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Drop static declaration to fix following build error if FRAME_POINTER disabled,
riscv64-linux-ld: arch/riscv/kernel/perf_callchain.o: in function `.L0':
perf_callchain.c:(.text+0x2b8): undefined reference to `walk_stackframe'
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
riscv:allnoconfig and riscv:tinyconfig fail to compile.
arch/riscv/kernel/stacktrace.c: In function 'walk_stackframe':
arch/riscv/kernel/stacktrace.c:78:8: error: 'sp_in_global' undeclared
sp_in_global is declared inside CONFIG_FRAME_POINTER but used outside
of it.
Fixes: 52e7c52d2d ("RISC-V: Stop relying on GCC's register allocator's hueristics")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
GCC allows users to hint to the register allocation that a variable should be
placed in a register by using a syntax along the lines of
function(...) {
register long in_REG __asm__("REG");
}
We've abused this a bit throughout the RISC-V port to access fixed registers
directly as C variables. In practice it's never going to blow up because GCC
isn't going to allocate these registers, but it's not a well defined syntax so
we really shouldn't be relying upon this. Luckily there is a very similar but
well defined syntax that allows us to still access these registers directly as
C variables, which is to simply declare the register variables globally. For
fixed variables this doesn't change the ABI.
LLVM disallows this ambiguous syntax, so this isn't just strictly a formatting
change.
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
This patch add support for perf callchain sampling on riscv platforms.
The return address of leaf function is retrieved from pt_regs as
it is not saved in the outmost frame.
Signed-off-by: Mao Han <han_mao@c-sky.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: linux-riscv <linux-riscv@lists.infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Guo Ren <guoren@kernel.org>
Tested-by: Greentime Hu <greentime.hu@sifive.com>
[paul.walmsley@sifive.com: fixed some 'checkpatch.pl --strict' issues;
fixed patch description spelling]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 655 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull RISC-V updates from Palmer Dabbelt:
"This contains an assortment of RISC-V related patches that I'd like to
target for the 5.2 merge window. Most of the patches are cleanups, but
there are a handful of user-visible changes:
- The nosmp and nr_cpus command-line arguments are now supported,
which work like normal.
- The SBI console no longer installs itself as a preferred console,
we rely on standard mechanisms (/chosen, command-line, hueristics)
instead.
- sfence_remove_sfence_vma{,_asid} now pass their arguments along to
the SBI call.
- Modules now support BUG().
- A missing sfence.vma during boot has been added. This bug only
manifests during boot.
- The arch/riscv support for SiFive's L2 cache controller has been
merged, which should un-block the EDAC framework work.
I've only tested this on QEMU again, as I didn't have time to get
things running on the Unleashed. The latest master from this morning
merges in cleanly and passes the tests as well"
* tag 'riscv-for-linus-5.2-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: (31 commits)
riscv: fix locking violation in page fault handler
RISC-V: sifive_l2_cache: Add L2 cache controller driver for SiFive SoCs
RISC-V: Add DT documentation for SiFive L2 Cache Controller
RISC-V: Avoid using invalid intermediate translations
riscv: Support BUG() in kernel module
riscv: Add the support for c.ebreak check in is_valid_bugaddr()
riscv: support trap-based WARN()
riscv: fix sbi_remote_sfence_vma{,_asid}.
riscv: move switch_mm to its own file
riscv: move flush_icache_{all,mm} to cacheflush.c
tty: Don't force RISCV SBI console as preferred console
RISC-V: Access CSRs using CSR numbers
RISC-V: Add interrupt related SCAUSE defines in asm/csr.h
RISC-V: Use tabs to align macro values in asm/csr.h
RISC-V: Fix minor checkpatch issues.
RISC-V: Support nr_cpus command line option.
RISC-V: Implement nosmp commandline option.
RISC-V: Add RISC-V specific arch_match_cpu_phys_id
riscv: vdso: drop unnecessary cc-ldoption
riscv: call pm_power_off from machine_halt / machine_power_off
...
HAVE_FUNCTION_GRAPH_RET_ADDR_PTR is always defined for RISC-V.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
In walk_stackframe, the pc now receives the address from calling
ftrace_graph_ret_addr instead of manual calculation.
Note that the original calculation,
pc = frame->ra - 4
is buggy when the instruction at the return address happened to be a
compressed inst. But since it is not a critical part of ftrace, it is
ignored for now to ease the review process.
Cc: Greentime Hu <greentime@andestech.com>
Signed-off-by: Alan Kao <alankao@andestech.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This patch contains code that is more specific to the RISC-V ISA than it
is to Linux. It contains string and math operations, C wrappers for
various assembly instructions, stack walking code, and uaccess.
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>