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| author | Thomas Renninger <trenn@suse.de> | 2010-08-06 16:11:02 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-10-22 10:16:42 -0700 |
| commit | a648ec05bb950fae2f35d0490ddd6cf15010af72 (patch) | |
| tree | cde3ca36db486e51d85c31619bf67f8d60215179 /lib | |
| parent | fd89cfb8718753459fcea3fe6103d19de5e86c9b (diff) | |
| download | linux-a648ec05bb950fae2f35d0490ddd6cf15010af72.tar.gz linux-a648ec05bb950fae2f35d0490ddd6cf15010af72.tar.bz2 linux-a648ec05bb950fae2f35d0490ddd6cf15010af72.zip | |
Dynamic Debug: Introduce ddebug_query= boot parameter
Dynamic debug lacks the ability to enable debug messages at boot time.
One could patch initramfs or service startup scripts to write to
/sys/../dynamic_debug/control, but this sucks.
This patch makes it possible to pass a query in the same format one can
write to /sys/../dynamic_debug/control via boot param.
When dynamic debug gets initialized, this query will automatically be
applied.
Signed-off-by: Thomas Renninger <trenn@suse.de>
Acked-by: jbaron@redhat.com
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/dynamic_debug.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index 84d103c474e4..44ce66bdb211 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -450,6 +450,19 @@ static int ddebug_exec_query(char *query_string) return 0; } +static __initdata char ddebug_setup_string[1024]; +static __init int ddebug_setup_query(char *str) +{ + if (strlen(str) >= 1024) { + pr_warning("ddebug boot param string too large\n"); + return 0; + } + strcpy(ddebug_setup_string, str); + return 1; +} + +__setup("ddebug_query=", ddebug_setup_query); + /* * File_ops->write method for <debugfs>/dynamic_debug/conrol. Gathers the * command text from userspace, parses and executes it. @@ -769,6 +782,18 @@ static int __init dynamic_debug_init(void) } ret = ddebug_add_module(iter_start, n, modname); } + + /* ddebug_query boot param got passed -> set it up */ + if (ddebug_setup_string[0] != '\0') { + ret = ddebug_exec_query(ddebug_setup_string); + if (ret) + pr_warning("Invalid ddebug boot param %s", + ddebug_setup_string); + else + pr_info("ddebug initialized with string %s", + ddebug_setup_string); + } + out_free: if (ret) { ddebug_remove_all_tables(); |