Merge unknown syscall method with extended detail method

[lttng-modules.git] / lttng-syscalls.c

diff --git a/lttng-syscalls.c b/lttng-syscalls.c
index c0550ab0d08b692c50fa1b205b0566a96eca9575..1872f161faa22955587c609bbc8eb7013edebcde 100644 (file)
--- a/lttng-syscalls.c
+++ b/lttng-syscalls.c
@@ -37,6 +37,7 @@ static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id);
 #define TRACE_INCLUDE_PATH ../instrumentation/syscalls/headers
 #include "instrumentation/syscalls/headers/syscalls_integers.h"
 #include "instrumentation/syscalls/headers/syscalls_pointers.h"
+#include "instrumentation/syscalls/headers/syscalls_unknown.h"
 
 #undef TP_MODULE_OVERRIDE
 #undef TP_PROBE_CB
@@ -66,6 +67,8 @@ static struct trace_syscall_entry sc_table[] = {
 #include "instrumentation/syscalls/headers/syscalls_pointers.h"
 };
 
+static int sc_table_filled;
+
 #undef CREATE_SYSCALL_TABLE
 
 static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
@@ -170,6 +173,27 @@ static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
        }
 }
 
+static void fill_sc_table(void)
+{
+       int i;
+
+       if (sc_table_filled) {
+               smp_rmb();      /* read flag before table */
+               return;
+       }
+
+       for (i = 0; i < ARRAY_SIZE(sc_table); i++) {
+               if (sc_table[i].func)
+                       continue;
+               sc_table[i].func = __event_probe__sys_unknown;
+               sc_table[i].nrargs = UNKNOWN_SYSCALL_NRARGS;
+               sc_table[i].fields = __event_fields___sys_unknown;
+               sc_table[i].desc = &__event_desc___sys_unknown;
+       }
+       smp_wmb();      /* Fill sc table before set flag to 1 */
+       sc_table_filled = 1;
+}
+
 int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
 {
        unsigned int i;
@@ -177,6 +201,8 @@ int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
 
        wrapper_vmalloc_sync_all();
 
+       fill_sc_table();
+
        if (!chan->sc_table) {
                /* create syscall table mapping syscall to events */
                chan->sc_table = kzalloc(sizeof(struct ltt_event *)
@@ -190,8 +216,7 @@ int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
                struct lttng_kernel_event ev;
                const struct lttng_event_desc *desc = sc_table[i].desc;
 
-               if (!desc)
-                       continue;
+               WARN_ON_ONCE(!desc);
                /*
                 * Skip those already populated by previous failed
                 * register for this channel.
@@ -216,6 +241,18 @@ int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
        }
        ret = tracepoint_probe_register("sys_enter",
                        (void *) syscall_entry_probe, chan);
+       if (ret)
+               return ret;
+       /*
+        * We change the name of sys_exit tracepoint due to namespace
+        * conflict with sys_exit syscall entry.
+        */
+       ret = tracepoint_probe_register("sys_exit",
+                       (void *) __event_probe__exit_syscall, chan);
+       if (ret) {
+               WARN_ON_ONCE(tracepoint_probe_unregister("sys_enter",
+                       (void *) syscall_entry_probe, chan));
+       }
        return ret;
 }
 
@@ -228,6 +265,10 @@ int lttng_syscalls_unregister(struct ltt_channel *chan)
 
        if (!chan->sc_table)
                return 0;
+       ret = tracepoint_probe_unregister("sys_exit",
+                       (void *) __event_probe__exit_syscall, chan);
+       if (ret)
+               return ret;
        ret = tracepoint_probe_unregister("sys_enter",
                        (void *) syscall_entry_probe, chan);
        if (ret)