diff options
| author | Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> | 2017-03-22 16:27:51 -0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-03-28 10:52:01 +1100 |
| commit | de78ae6c9ef55d9ded036c8e29d9364e1ce5f6b7 (patch) | |
| tree | e70328b63d61c53260098aef326628845f62d321 /arch/powerpc/xmon | |
| parent | b561783c7bfd4bcb18ad30e1410ee19500c36a7c (diff) | |
powerpc/xmon: add debugfs entry for xmon
Currently the xmon debugger is set only via kernel boot command-line.
It's disabled by default, and can be enabled with "xmon=on" on the
command-line. Also, xmon may be accessed via sysrq mechanism.
But we cannot enable/disable xmon in runtime, it needs kernel reload.
This patch introduces a debugfs entry for xmon, allowing user to query
its current state and change it if desired. Basically, the "xmon" file
to read from/write to is under the debugfs mount point, on powerpc
directory. It's a simple attribute, value 0 meaning xmon is disabled
and value 1 the opposite. Writing these states to the file will take
immediate effect in the debugger.
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/xmon')
| -rw-r--r-- | arch/powerpc/xmon/xmon.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c index 25a32815f310..0fab9d7349eb 100644 --- a/arch/powerpc/xmon/xmon.c +++ b/arch/powerpc/xmon/xmon.c @@ -29,6 +29,10 @@ #include <linux/nmi.h> #include <linux/ctype.h> +#ifdef CONFIG_DEBUG_FS +#include <linux/debugfs.h> +#endif + #include <asm/ptrace.h> #include <asm/string.h> #include <asm/prom.h> @@ -3316,6 +3320,33 @@ static int __init setup_xmon_sysrq(void) device_initcall(setup_xmon_sysrq); #endif /* CONFIG_MAGIC_SYSRQ */ +#ifdef CONFIG_DEBUG_FS +static int xmon_dbgfs_set(void *data, u64 val) +{ + xmon_on = !!val; + xmon_init(xmon_on); + + return 0; +} + +static int xmon_dbgfs_get(void *data, u64 *val) +{ + *val = xmon_on; + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(xmon_dbgfs_ops, xmon_dbgfs_get, + xmon_dbgfs_set, "%llu\n"); + +static int __init setup_xmon_dbgfs(void) +{ + debugfs_create_file("xmon", 0600, powerpc_debugfs_root, NULL, + &xmon_dbgfs_ops); + return 0; +} +device_initcall(setup_xmon_dbgfs); +#endif /* CONFIG_DEBUG_FS */ + static int xmon_early __initdata; static int __init early_parse_xmon(char *p) |