diff options
| author | Ian Munsie <imunsie@au1.ibm.com> | 2011-02-03 14:27:22 +1100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2011-02-07 21:26:22 -0500 |
| commit | c763ba06bd9b5db2c46c36276c89103d92d2c604 (patch) | |
| tree | 776ce215fc5900e747fb79dc91a160da35f4325c | |
| parent | 3773b389b6927595512558594d040c1edba46f36 (diff) | |
| download | lwn-c763ba06bd9b5db2c46c36276c89103d92d2c604.tar.gz lwn-c763ba06bd9b5db2c46c36276c89103d92d2c604.zip | |
tracing/syscalls: Make arch_syscall_addr weak
Some architectures use non-trivial system call tables and will not work
with the generic arch_syscall_addr code. For example, PowerPC64 uses a
table of twin long longs.
This patch makes the generic arch_syscall_addr weak to allow
architectures with non-trivial system call tables to override it.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
LKML-Reference: <1296703645-18718-4-git-send-email-imunsie@au1.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
| -rw-r--r-- | Documentation/trace/ftrace-design.txt | 3 | ||||
| -rw-r--r-- | kernel/trace/trace_syscalls.c | 2 |
2 files changed, 4 insertions, 1 deletions
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt index dc52bd442c92..6fca17beee2f 100644 --- a/Documentation/trace/ftrace-design.txt +++ b/Documentation/trace/ftrace-design.txt @@ -247,6 +247,9 @@ You need very few things to get the syscalls tracing in an arch. - Support the TIF_SYSCALL_TRACEPOINT thread flags. - Put the trace_sys_enter() and trace_sys_exit() tracepoints calls from ptrace in the ptrace syscalls tracing path. +- If the system call table on this arch is more complicated than a simple array + of addresses of the system calls, implement an arch_syscall_addr to return + the address of a given system call. - Tag this arch as HAVE_SYSCALL_TRACEPOINTS. diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 423094288fb5..af831545f656 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -446,7 +446,7 @@ int init_syscall_trace(struct ftrace_event_call *call) return id; } -unsigned long __init arch_syscall_addr(int nr) +unsigned long __init __weak arch_syscall_addr(int nr) { return (unsigned long)sys_call_table[nr]; } |