From: Francis Deslauriers <francis.deslauriers@efficios.com>
Date: Thu, 23 Jan 2020 23:31:06 +0000 (-0500)
Subject: lttng-syscalls.c: extract function calling actual probe
X-Git-Tag: v2.13.0-rc1~128
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=63aa91609c6b8140e5382ecc0f94dc555b62af7b;p=lttng-modules.git

lttng-syscalls.c: extract function calling actual probe

This function will be reused by the event notifier infrastructure.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: Iad25a44202d74eac8f75af108eb8297d82303d63
---

diff --git a/src/lttng-syscalls.c b/src/lttng-syscalls.c
index 3d9f3736..3139a556 100644
--- a/src/lttng-syscalls.c
+++ b/src/lttng-syscalls.c
@@ -387,77 +387,36 @@ static void syscall_entry_event_unknown(struct lttng_event *event,
 		__event_probe__syscall_entry_unknown(event, id, args);
 }
 
-void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
+static __always_inline
+void syscall_entry_call_func(void *func, unsigned int nrargs, void *data,
+		struct pt_regs *regs)
 {
-	struct lttng_channel *chan = __data;
-	struct lttng_event *event, *unknown_event;
-	const struct trace_syscall_entry *table, *entry;
-	size_t table_len;
-
-	if (unlikely(in_compat_syscall())) {
-		struct lttng_syscall_filter *filter = chan->sc_filter;
-
-		if (id < 0 || id >= NR_compat_syscalls
-			|| (!READ_ONCE(chan->syscall_all) && !test_bit(id, filter->sc_compat_entry))) {
-			/* System call filtered out. */
-			return;
-		}
-		table = compat_sc_table;
-		table_len = ARRAY_SIZE(compat_sc_table);
-		unknown_event = chan->sc_compat_unknown;
-	} else {
-		struct lttng_syscall_filter *filter = chan->sc_filter;
-
-		if (id < 0 || id >= NR_syscalls
-			|| (!READ_ONCE(chan->syscall_all) && !test_bit(id, filter->sc_entry))) {
-			/* System call filtered out. */
-			return;
-		}
-		table = sc_table;
-		table_len = ARRAY_SIZE(sc_table);
-		unknown_event = chan->sc_unknown;
-	}
-	if (unlikely(id < 0 || id >= table_len)) {
-		syscall_entry_event_unknown(unknown_event, regs, id);
-		return;
-	}
-	if (unlikely(in_compat_syscall()))
-		event = chan->compat_sc_table[id];
-	else
-		event = chan->sc_table[id];
-	if (unlikely(!event)) {
-		syscall_entry_event_unknown(unknown_event, regs, id);
-		return;
-	}
-	entry = &table[id];
-	WARN_ON_ONCE(!entry);
-
-	switch (entry->nrargs) {
+	switch (nrargs) {
 	case 0:
 	{
-		void (*fptr)(void *__data) = entry->event_func;
+		void (*fptr)(void *__data) = func;
 
-		fptr(event);
+		fptr(data);
 		break;
 	}
 	case 1:
 	{
-		void (*fptr)(void *__data, unsigned long arg0) = entry->event_func;
+		void (*fptr)(void *__data, unsigned long arg0) = func;
 		unsigned long args[LTTNG_SYSCALL_NR_ARGS];
 
 		lttng_syscall_get_arguments(current, regs, args);
-		fptr(event, args[0]);
+		fptr(data, args[0]);
 		break;
 	}
 	case 2:
 	{
 		void (*fptr)(void *__data,
 			unsigned long arg0,
-			unsigned long arg1) = entry->event_func;
+			unsigned long arg1) = func;
 		unsigned long args[LTTNG_SYSCALL_NR_ARGS];
 
 		lttng_syscall_get_arguments(current, regs, args);
-		fptr(event, args[0], args[1]);
+		fptr(data, args[0], args[1]);
 		break;
 	}
 	case 3:
@@ -465,11 +424,11 @@ void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
 		void (*fptr)(void *__data,
 			unsigned long arg0,
 			unsigned long arg1,
-			unsigned long arg2) = entry->event_func;
+			unsigned long arg2) = func;
 		unsigned long args[LTTNG_SYSCALL_NR_ARGS];
 
 		lttng_syscall_get_arguments(current, regs, args);
-		fptr(event, args[0], args[1], args[2]);
+		fptr(data, args[0], args[1], args[2]);
 		break;
 	}
 	case 4:
@@ -478,11 +437,11 @@ void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
 			unsigned long arg0,
 			unsigned long arg1,
 			unsigned long arg2,
-			unsigned long arg3) = entry->event_func;
+			unsigned long arg3) = func;
 		unsigned long args[LTTNG_SYSCALL_NR_ARGS];
 
 		lttng_syscall_get_arguments(current, regs, args);
-		fptr(event, args[0], args[1], args[2], args[3]);
+		fptr(data, args[0], args[1], args[2], args[3]);
 		break;
 	}
 	case 5:
@@ -492,11 +451,11 @@ void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
 			unsigned long arg1,
 			unsigned long arg2,
 			unsigned long arg3,
-			unsigned long arg4) = entry->event_func;
+			unsigned long arg4) = func;
 		unsigned long args[LTTNG_SYSCALL_NR_ARGS];
 
 		lttng_syscall_get_arguments(current, regs, args);
-		fptr(event, args[0], args[1], args[2], args[3], args[4]);
+		fptr(data, args[0], args[1], args[2], args[3], args[4]);
 		break;
 	}
 	case 6:
@@ -507,11 +466,11 @@ void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
 			unsigned long arg2,
 			unsigned long arg3,
 			unsigned long arg4,
-			unsigned long arg5) = entry->event_func;
+			unsigned long arg5) = func;
 		unsigned long args[LTTNG_SYSCALL_NR_ARGS];
 
 		lttng_syscall_get_arguments(current, regs, args);
-		fptr(event, args[0], args[1], args[2],
+		fptr(data, args[0], args[1], args[2],
 			args[3], args[4], args[5]);
 		break;
 	}
@@ -520,6 +479,53 @@ void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
 	}
 }
 
+void syscall_entry_event_probe(void *__data, struct pt_regs *regs, long id)
+{
+	struct lttng_channel *chan = __data;
+	struct lttng_event *event, *unknown_event;
+	const struct trace_syscall_entry *table, *entry;
+	size_t table_len;
+
+	if (unlikely(in_compat_syscall())) {
+		struct lttng_syscall_filter *filter = chan->sc_filter;
+
+		if (id < 0 || id >= NR_compat_syscalls
+			|| (!READ_ONCE(chan->syscall_all) && !test_bit(id, filter->sc_compat_entry))) {
+			/* System call filtered out. */
+			return;
+		}
+		table = compat_sc_table;
+		table_len = ARRAY_SIZE(compat_sc_table);
+		unknown_event = chan->sc_compat_unknown;
+	} else {
+		struct lttng_syscall_filter *filter = chan->sc_filter;
+
+		if (id < 0 || id >= NR_syscalls
+			|| (!READ_ONCE(chan->syscall_all) && !test_bit(id, filter->sc_entry))) {
+			/* System call filtered out. */
+			return;
+		}
+		table = sc_table;
+		table_len = ARRAY_SIZE(sc_table);
+		unknown_event = chan->sc_unknown;
+	}
+	if (unlikely(id < 0 || id >= table_len)) {
+		syscall_entry_event_unknown(unknown_event, regs, id);
+		return;
+	}
+	if (unlikely(in_compat_syscall()))
+		event = chan->compat_sc_table[id];
+	else
+		event = chan->sc_table[id];
+	if (unlikely(!event)) {
+		syscall_entry_event_unknown(unknown_event, regs, id);
+		return;
+	}
+	entry = &table[id];
+	WARN_ON_ONCE(!entry);
+	syscall_entry_call_func(entry->event_func, entry->nrargs, event, regs);
+}
+
 static void syscall_exit_event_unknown(struct lttng_event *event,
 	struct pt_regs *regs, int id, long ret)
 {