Cleanup: remove logically dead code

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

diff --git a/lttng-syscalls.c b/lttng-syscalls.c
index ee09a0419498a07f0dc06a0bb0f56afcc8a3771a..5fa66660b5f2532d715e80d90fb7c8feb6ec08ca 100644 (file)
--- a/lttng-syscalls.c
+++ b/lttng-syscalls.c
@@ -37,6 +37,7 @@
 #include "lib/bitfield.h"
 #include "wrapper/tracepoint.h"
 #include "wrapper/file.h"
+#include "wrapper/rcu.h"
 #include "lttng-events.h"
 
 #ifndef CONFIG_COMPAT
@@ -76,6 +77,7 @@ struct oldold_utsname;
 struct old_utsname;
 struct sel_arg_struct;
 struct mmap_arg_struct;
+struct file_handle;
 
 #ifdef IA32_NR_syscalls
 #define NR_compat_syscalls IA32_NR_syscalls
@@ -113,16 +115,15 @@ struct mmap_arg_struct;
 /* Hijack probe callback for system call enter */
 #undef TP_PROBE_CB
 #define TP_PROBE_CB(_template)         &syscall_entry_probe
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
        LTTNG_TRACEPOINT_EVENT(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+               PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \
        LTTNG_TRACEPOINT_EVENT_CODE(syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
                PARAMS(_locvar), PARAMS(_code),                                 \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
-       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_entry_##_name, PARAMS(_struct), PARAMS(_assign), \
-               PARAMS(_printk))
+               PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
+       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_entry_##_name, PARAMS(_fields))
 #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name)            \
        LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_entry_##_template, syscall_entry_##_name)
 #undef TRACE_SYSTEM
@@ -146,17 +147,14 @@ struct mmap_arg_struct;
 
 /* Hijack probe callback for compat system call enter */
 #define TP_PROBE_CB(_template)         &syscall_entry_probe
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
        LTTNG_TRACEPOINT_EVENT(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_struct), PARAMS(_assign),                               \
-               PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+               PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \
        LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_entry_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_locvar), PARAMS(_code),                                 \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
-       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_entry_##_name, PARAMS(_struct), \
-               PARAMS(_assign), PARAMS(_printk))
+               PARAMS(_locvar), PARAMS(_code), PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
+       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_entry_##_name, PARAMS(_fields))
 #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name)            \
        LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_entry_##_template, \
                compat_syscall_entry_##_name)
@@ -193,16 +191,14 @@ struct mmap_arg_struct;
 
 /* Hijack probe callback for system call exit */
 #define TP_PROBE_CB(_template)         &syscall_exit_probe
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
        LTTNG_TRACEPOINT_EVENT(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+               PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \
        LTTNG_TRACEPOINT_EVENT_CODE(syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_locvar), PARAMS(_code),                                 \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
-       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_exit_##_name, PARAMS(_struct), \
-               PARAMS(_assign), PARAMS(_printk))
+               PARAMS(_locvar), PARAMS(_code), PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
+       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(syscall_exit_##_name, PARAMS(_fields))
 #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name)            \
        LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(syscall_exit_##_template,        \
                syscall_exit_##_name)
@@ -227,16 +223,14 @@ struct mmap_arg_struct;
 
 /* Hijack probe callback for compat system call exit */
 #define TP_PROBE_CB(_template)         &syscall_exit_probe
-#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+#define SC_LTTNG_TRACEPOINT_EVENT(_name, _proto, _args, _fields) \
        LTTNG_TRACEPOINT_EVENT(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _struct, _assign, _printk) \
+               PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CODE(_name, _proto, _args, _locvar, _code, _fields) \
        LTTNG_TRACEPOINT_EVENT_CODE(compat_syscall_exit_##_name, PARAMS(_proto), PARAMS(_args), \
-               PARAMS(_locvar), PARAMS(_code),                                 \
-               PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
-#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
-       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_exit_##_name, PARAMS(_struct), \
-               PARAMS(_assign), PARAMS(_printk))
+               PARAMS(_locvar), PARAMS(_code), PARAMS(_fields))
+#define SC_LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields) \
+       LTTNG_TRACEPOINT_EVENT_CLASS_NOARGS(compat_syscall_exit_##_name, PARAMS(_fields))
 #define SC_LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name)            \
        LTTNG_TRACEPOINT_EVENT_INSTANCE_NOARGS(compat_syscall_exit_##_template, \
                compat_syscall_exit_##_name)
@@ -376,7 +370,7 @@ void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
        if (unlikely(is_compat_task())) {
                struct lttng_syscall_filter *filter;
 
-               filter = rcu_dereference(chan->sc_filter);
+               filter = lttng_rcu_dereference(chan->sc_filter);
                if (filter) {
                        if (id < 0 || id >= NR_compat_syscalls
                                || !test_bit(id, filter->sc_compat)) {
@@ -390,7 +384,7 @@ void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
        } else {
                struct lttng_syscall_filter *filter;
 
-               filter = rcu_dereference(chan->sc_filter);
+               filter = lttng_rcu_dereference(chan->sc_filter);
                if (filter) {
                        if (id < 0 || id >= NR_syscalls
                                || !test_bit(id, filter->sc)) {
@@ -530,7 +524,7 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret)
        if (unlikely(is_compat_task())) {
                struct lttng_syscall_filter *filter;
 
-               filter = rcu_dereference(chan->sc_filter);
+               filter = lttng_rcu_dereference(chan->sc_filter);
                if (filter) {
                        if (id < 0 || id >= NR_compat_syscalls
                                || !test_bit(id, filter->sc_compat)) {
@@ -544,7 +538,7 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret)
        } else {
                struct lttng_syscall_filter *filter;
 
-               filter = rcu_dereference(chan->sc_filter);
+               filter = lttng_rcu_dereference(chan->sc_filter);
                if (filter) {
                        if (id < 0 || id >= NR_syscalls
                                || !test_bit(id, filter->sc)) {
@@ -666,7 +660,10 @@ void syscall_exit_probe(void *__data, struct pt_regs *regs, long ret)
        }
 }
 
-/* noinline to diminish caller stack size */
+/*
+ * noinline to diminish caller stack size.
+ * Should be called with sessions lock held.
+ */
 static
 int fill_table(const struct trace_syscall_entry *table, size_t table_len,
        struct lttng_event **chan_table, struct lttng_channel *chan,
@@ -715,8 +712,8 @@ int fill_table(const struct trace_syscall_entry *table, size_t table_len,
                strncat(ev.name, desc->name,
                        LTTNG_KERNEL_SYM_NAME_LEN - strlen(ev.name) - 1);
                ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-               ev.instrumentation = LTTNG_KERNEL_NOOP;
-               chan_table[i] = lttng_event_create(chan, &ev, filter,
+               ev.instrumentation = LTTNG_KERNEL_SYSCALL;
+               chan_table[i] = _lttng_event_create(chan, &ev, filter,
                                                desc, ev.instrumentation);
                WARN_ON_ONCE(!chan_table[i]);
                if (IS_ERR(chan_table[i])) {
@@ -732,6 +729,9 @@ int fill_table(const struct trace_syscall_entry *table, size_t table_len,
        return 0;
 }
 
+/*
+ * Should be called with sessions lock held.
+ */
 int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
 {
        struct lttng_kernel_event ev;
@@ -779,8 +779,8 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                memset(&ev, 0, sizeof(ev));
                strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
                ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-               ev.instrumentation = LTTNG_KERNEL_NOOP;
-               chan->sc_unknown = lttng_event_create(chan, &ev, filter,
+               ev.instrumentation = LTTNG_KERNEL_SYSCALL;
+               chan->sc_unknown = _lttng_event_create(chan, &ev, filter,
                                                desc,
                                                ev.instrumentation);
                WARN_ON_ONCE(!chan->sc_unknown);
@@ -796,8 +796,8 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                memset(&ev, 0, sizeof(ev));
                strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
                ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-               ev.instrumentation = LTTNG_KERNEL_NOOP;
-               chan->sc_compat_unknown = lttng_event_create(chan, &ev, filter,
+               ev.instrumentation = LTTNG_KERNEL_SYSCALL;
+               chan->sc_compat_unknown = _lttng_event_create(chan, &ev, filter,
                                                desc,
                                                ev.instrumentation);
                WARN_ON_ONCE(!chan->sc_unknown);
@@ -813,8 +813,8 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                memset(&ev, 0, sizeof(ev));
                strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
                ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-               ev.instrumentation = LTTNG_KERNEL_NOOP;
-               chan->compat_sc_exit_unknown = lttng_event_create(chan, &ev,
+               ev.instrumentation = LTTNG_KERNEL_SYSCALL;
+               chan->compat_sc_exit_unknown = _lttng_event_create(chan, &ev,
                                                filter, desc,
                                                ev.instrumentation);
                WARN_ON_ONCE(!chan->compat_sc_exit_unknown);
@@ -830,8 +830,8 @@ int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
                memset(&ev, 0, sizeof(ev));
                strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
                ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
-               ev.instrumentation = LTTNG_KERNEL_NOOP;
-               chan->sc_exit_unknown = lttng_event_create(chan, &ev, filter,
+               ev.instrumentation = LTTNG_KERNEL_SYSCALL;
+               chan->sc_exit_unknown = _lttng_event_create(chan, &ev, filter,
                                                desc, ev.instrumentation);
                WARN_ON_ONCE(!chan->sc_exit_unknown);
                if (IS_ERR(chan->sc_exit_unknown)) {
@@ -1290,10 +1290,6 @@ int lttng_abi_syscall_list(void)
        if (ret < 0)
                goto open_error;
        fd_install(file_fd, syscall_list_file);
-       if (file_fd < 0) {
-               ret = file_fd;
-               goto fd_error;
-       }
        return file_fd;
 
 open_error: