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| author | Boqun Feng <boqun.feng@gmail.com> | 2016-11-22 12:20:09 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2018-08-10 15:12:35 +0300 |
| commit | 302c7b0c4ff5aed585419603f835dee30207e5d5 (patch) | |
| tree | 509bc52c839c0ebdafd7eef8a52d11cfa092a31b | |
| parent | 646dbe40fa2a54118975792fa9b98cefac7d232e (diff) | |
| download | linux-302c7b0c4ff5aed585419603f835dee30207e5d5.tar.xz | |
powerpc/xmon: Add address lookup for percpu symbols
Currently, in xmon, there is no obvious way to get an address for a
percpu symbol for a particular cpu. Having such an ability would be
good for debugging the system when percpu variables got involved.
Therefore, this patch introduces a new xmon command "lp" to lookup the
address for percpu symbols. Usage of "lp" is similar to "ls", except
that we could add a cpu number to choose the variable of which cpu we
want to lookup. If no cpu number is given, lookup for current cpu.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| -rw-r--r-- | arch/powerpc/xmon/xmon.c | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index b7dd683b0470..7c4aa5b00302 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -56,6 +56,7 @@ #include <asm/opal.h> #include <asm/firmware.h> #include <asm/code-patching.h> +#include <asm/sections.h> #ifdef CONFIG_PPC64 #include <asm/hvcall.h> @@ -244,6 +245,7 @@ Commands:\n\ f flush cache\n\ la lookup symbol+offset of specified address\n\ ls lookup address of specified symbol\n\ + lp s [#] lookup address of percpu symbol s for current cpu, or cpu #\n\ m examine/change memory\n\ mm move a block of memory\n\ ms set a block of memory\n\ @@ -3352,7 +3354,8 @@ static void symbol_lookup(void) { int type = inchar(); - unsigned long addr; + unsigned long addr, cpu; + void __percpu *ptr = NULL; static char tmp[64]; switch (type) { @@ -3376,6 +3379,34 @@ symbol_lookup(void) catch_memory_errors = 0; termch = 0; break; + case 'p': + getstring(tmp, 64); + if (setjmp(bus_error_jmp) == 0) { + catch_memory_errors = 1; + sync(); + ptr = (void __percpu *)kallsyms_lookup_name(tmp); + sync(); + } + + if (ptr && + ptr >= (void __percpu *)__per_cpu_start && + ptr < (void __percpu *)__per_cpu_end) + { + if (scanhex(&cpu) && cpu < num_possible_cpus()) { + addr = (unsigned long)per_cpu_ptr(ptr, cpu); + } else { + cpu = raw_smp_processor_id(); + addr = (unsigned long)this_cpu_ptr(ptr); + } + + printf("%s for cpu 0x%lx: %lx\n", tmp, cpu, addr); + } else { + printf("Percpu symbol '%s' not found.\n", tmp); + } + + catch_memory_errors = 0; + termch = 0; + break; } } |