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-rw-r--r--arch/x86/kernel/Makefile_323
-rw-r--r--arch/x86/kernel/ft_event.c104
-rw-r--r--include/asm-x86/feather_trace.h93
3 files changed, 200 insertions, 0 deletions
diff --git a/arch/x86/kernel/Makefile_32 b/arch/x86/kernel/Makefile_32
index a7bc93c27662..5f87f32ada6f 100644
--- a/arch/x86/kernel/Makefile_32
+++ b/arch/x86/kernel/Makefile_32
@@ -49,6 +49,9 @@ obj-y += pcspeaker.o
49 49
50obj-$(CONFIG_SCx200) += scx200_32.o 50obj-$(CONFIG_SCx200) += scx200_32.o
51 51
52obj-$(CONFIG_FEATHER_TRACE) += ft_event.o
53
54
52# vsyscall_32.o contains the vsyscall DSO images as __initdata. 55# vsyscall_32.o contains the vsyscall DSO images as __initdata.
53# We must build both images before we can assemble it. 56# We must build both images before we can assemble it.
54# Note: kbuild does not track this dependency due to usage of .incbin 57# Note: kbuild does not track this dependency due to usage of .incbin
diff --git a/arch/x86/kernel/ft_event.c b/arch/x86/kernel/ft_event.c
new file mode 100644
index 000000000000..b1d80c52d793
--- /dev/null
+++ b/arch/x86/kernel/ft_event.c
@@ -0,0 +1,104 @@
1#include <linux/types.h>
2
3#include <litmus/feather_trace.h>
4
5/* the feather trace management functions assume
6 * exclusive access to the event table
7 */
8
9
10#define BYTE_JUMP 0xeb
11#define BYTE_JUMP_LEN 0x02
12
13/* for each event, there is an entry in the event table */
14struct trace_event {
15 long id;
16 long count;
17 long start_addr;
18 long end_addr;
19};
20
21extern struct trace_event __start___event_table[];
22extern struct trace_event __stop___event_table[];
23
24int ft_enable_event(unsigned long id)
25{
26 struct trace_event* te = __start___event_table;
27 int count = 0;
28 char* delta;
29 unsigned char* instr;
30
31 while (te < __stop___event_table) {
32 if (te->id == id && ++te->count == 1) {
33 instr = (unsigned char*) te->start_addr;
34 /* make sure we don't clobber something wrong */
35 if (*instr == BYTE_JUMP) {
36 delta = (((unsigned char*) te->start_addr) + 1);
37 *delta = 0;
38 }
39 }
40 if (te->id == id)
41 count++;
42 te++;
43 }
44 return count;
45}
46
47int ft_disable_event(unsigned long id)
48{
49 struct trace_event* te = __start___event_table;
50 int count = 0;
51 char* delta;
52 unsigned char* instr;
53
54 while (te < __stop___event_table) {
55 if (te->id == id && --te->count == 0) {
56 instr = (unsigned char*) te->start_addr;
57 if (*instr == BYTE_JUMP) {
58 delta = (((unsigned char*) te->start_addr) + 1);
59 *delta = te->end_addr - te->start_addr -
60 BYTE_JUMP_LEN;
61 }
62 }
63 if (te->id == id)
64 count++;
65 te++;
66 }
67 return count;
68}
69
70int ft_disable_all_events(void)
71{
72 struct trace_event* te = __start___event_table;
73 int count = 0;
74 char* delta;
75 unsigned char* instr;
76
77 while (te < __stop___event_table) {
78 if (te->count) {
79 instr = (unsigned char*) te->start_addr;
80 if (*instr == BYTE_JUMP) {
81 delta = (((unsigned char*) te->start_addr)
82 + 1);
83 *delta = te->end_addr - te->start_addr -
84 BYTE_JUMP_LEN;
85 te->count = 0;
86 count++;
87 }
88 }
89 te++;
90 }
91 return count;
92}
93
94int ft_is_event_enabled(unsigned long id)
95{
96 struct trace_event* te = __start___event_table;
97
98 while (te < __stop___event_table) {
99 if (te->id == id)
100 return te->count;
101 te++;
102 }
103 return 0;
104}
diff --git a/include/asm-x86/feather_trace.h b/include/asm-x86/feather_trace.h
index f60fbed07afb..253067eceeec 100644
--- a/include/asm-x86/feather_trace.h
+++ b/include/asm-x86/feather_trace.h
@@ -1,6 +1,97 @@
1#ifndef _ARCH_FEATHER_TRACE_H 1#ifndef _ARCH_FEATHER_TRACE_H
2#define _ARCH_FEATHER_TRACE_H 2#define _ARCH_FEATHER_TRACE_H
3 3
4static inline int fetch_and_inc(int *val)
5{
6 int ret = 1;
7 __asm__ __volatile__("lock; xaddl %0, %1" : "+r" (ret), "+m" (*val) : : "memory" );
8 return ret;
9}
10
11static inline int fetch_and_dec(int *val)
12{
13 int ret = -1;
14 __asm__ __volatile__("lock; xaddl %0, %1" : "+r" (ret), "+m" (*val) : : "memory" );
15 return ret;
16}
17
18#define feather_callback __attribute__((regparm(0)))
19
20/* make the compiler reload any register that is not saved in
21 * a cdecl function call
22 */
23#define CLOBBER_LIST "memory", "cc", "eax", "ecx", "edx"
24
25#define ft_event(id, callback) \
26 __asm__ __volatile__( \
27 "1: jmp 2f \n\t" \
28 " call " #callback " \n\t" \
29 ".section __event_table, \"aw\" \n\t" \
30 ".long " #id ", 0, 1b, 2f \n\t" \
31 ".previous \n\t" \
32 "2: \n\t" \
33 : : : CLOBBER_LIST)
34
35#define ft_event0(id, callback) \
36 __asm__ __volatile__( \
37 "1: jmp 2f \n\t" \
38 " subl $4, %%esp \n\t" \
39 " movl $" #id ", (%%esp) \n\t" \
40 " call " #callback " \n\t" \
41 " addl $4, %%esp \n\t" \
42 ".section __event_table, \"aw\" \n\t" \
43 ".long " #id ", 0, 1b, 2f \n\t" \
44 ".previous \n\t" \
45 "2: \n\t" \
46 : : : CLOBBER_LIST)
47
48#define ft_event1(id, callback, param) \
49 __asm__ __volatile__( \
50 "1: jmp 2f \n\t" \
51 " subl $8, %%esp \n\t" \
52 " movl %0, 4(%%esp) \n\t" \
53 " movl $" #id ", (%%esp) \n\t" \
54 " call " #callback " \n\t" \
55 " addl $8, %%esp \n\t" \
56 ".section __event_table, \"aw\" \n\t" \
57 ".long " #id ", 0, 1b, 2f \n\t" \
58 ".previous \n\t" \
59 "2: \n\t" \
60 : : "r" (param) : CLOBBER_LIST)
61
62#define ft_event2(id, callback, param, param2) \
63 __asm__ __volatile__( \
64 "1: jmp 2f \n\t" \
65 " subl $12, %%esp \n\t" \
66 " movl %1, 8(%%esp) \n\t" \
67 " movl %0, 4(%%esp) \n\t" \
68 " movl $" #id ", (%%esp) \n\t" \
69 " call " #callback " \n\t" \
70 " addl $12, %%esp \n\t" \
71 ".section __event_table, \"aw\" \n\t" \
72 ".long " #id ", 0, 1b, 2f \n\t" \
73 ".previous \n\t" \
74 "2: \n\t" \
75 : : "r" (param), "r" (param2) : CLOBBER_LIST)
76
77
78#define ft_event3(id, callback, p, p2, p3) \
79 __asm__ __volatile__( \
80 "1: jmp 2f \n\t" \
81 " subl $16, %%esp \n\t" \
82 " movl %1, 12(%%esp) \n\t" \
83 " movl %1, 8(%%esp) \n\t" \
84 " movl %0, 4(%%esp) \n\t" \
85 " movl $" #id ", (%%esp) \n\t" \
86 " call " #callback " \n\t" \
87 " addl $16, %%esp \n\t" \
88 ".section __event_table, \"aw\" \n\t" \
89 ".long " #id ", 0, 1b, 2f \n\t" \
90 ".previous \n\t" \
91 "2: \n\t" \
92 : : "r" (p), "r" (p2), "r" (p3) : CLOBBER_LIST)
93
94
4static inline unsigned long long ft_timestamp(void) 95static inline unsigned long long ft_timestamp(void)
5{ 96{
6 unsigned long long ret; 97 unsigned long long ret;
@@ -8,4 +99,6 @@ static inline unsigned long long ft_timestamp(void)
8 return ret; 99 return ret;
9} 100}
10 101
102#define __ARCH_HAS_FEATHER_TRACE
103
11#endif 104#endif
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-21 13:25:13 -0500