There are 7 function definitions in trace_probe_tmpl.h, they are:
1, process_fetch_insn
2, fetch_store_strlen
3, fetch_store_string
4, fetch_store_strlen_user
5, fetch_store_string_user
6, probe_mem_read
7, probe_mem_read_user
Every C file which includes trace_probe_tmpl.h has to implement them,
otherwise it gets warnings and errors. However, some of them are identical,
like kprobe and eprobe, as a result, there is a lot redundant code in those
2 files.
This patch would like to provide default behaviors for those functions
which kprobe and eprobe can share by just including trace_probe_kernel.h
with trace_probe_tmpl.h together.
It removes redundant code, increases readability, and more importantly,
makes it easier to introduce a new feature based on trace probe
(it's possible).
Signed-off-by: Song Chen <[email protected]>
---
kernel/trace/trace_eprobe.c | 144 ------------------------------
kernel/trace/trace_events_synth.c | 7 +-
kernel/trace/trace_kprobe.c | 102 ---------------------
kernel/trace/trace_probe_kernel.h | 140 +++++++++++++++++++++++++++--
4 files changed, 138 insertions(+), 255 deletions(-)
diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index bdb26eee7a0c..60ced4a7a25d 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -319,64 +319,6 @@ print_eprobe_event(struct trace_iterator *iter, int flags,
return trace_handle_return(s);
}
-static unsigned long get_event_field(struct fetch_insn *code, void *rec)
-{
- struct ftrace_event_field *field = code->data;
- unsigned long val;
- void *addr;
-
- addr = rec + field->offset;
-
- if (is_string_field(field)) {
- switch (field->filter_type) {
- case FILTER_DYN_STRING:
- val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
- break;
- case FILTER_RDYN_STRING:
- val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
- break;
- case FILTER_STATIC_STRING:
- val = (unsigned long)addr;
- break;
- case FILTER_PTR_STRING:
- val = (unsigned long)(*(char *)addr);
- break;
- default:
- WARN_ON_ONCE(1);
- return 0;
- }
- return val;
- }
-
- switch (field->size) {
- case 1:
- if (field->is_signed)
- val = *(char *)addr;
- else
- val = *(unsigned char *)addr;
- break;
- case 2:
- if (field->is_signed)
- val = *(short *)addr;
- else
- val = *(unsigned short *)addr;
- break;
- case 4:
- if (field->is_signed)
- val = *(int *)addr;
- else
- val = *(unsigned int *)addr;
- break;
- default:
- if (field->is_signed)
- val = *(long *)addr;
- else
- val = *(unsigned long *)addr;
- break;
- }
- return val;
-}
-
static int get_eprobe_size(struct trace_probe *tp, void *rec)
{
struct fetch_insn *code;
@@ -419,92 +361,6 @@ static int get_eprobe_size(struct trace_probe *tp, void *rec)
return ret;
}
-/* Kprobe specific fetch functions */
-
-/* Note that we don't verify it, since the code does not come from user space */
-static int
-process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
- void *base)
-{
- unsigned long val;
-
- retry:
- switch (code->op) {
- case FETCH_OP_TP_ARG:
- val = get_event_field(code, rec);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = (unsigned long)current->comm;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
- case FETCH_NOP_SYMBOL: /* Ignore a place holder */
- code++;
- goto retry;
- default:
- return -EILSEQ;
- }
- code++;
- return process_fetch_insn_bottom(code, val, dest, base);
-}
-NOKPROBE_SYMBOL(process_fetch_insn)
-
-/* Return the length of string -- including null terminal byte */
-static nokprobe_inline int
-fetch_store_strlen_user(unsigned long addr)
-{
- return kern_fetch_store_strlen_user(addr);
-}
-
-/* Return the length of string -- including null terminal byte */
-static nokprobe_inline int
-fetch_store_strlen(unsigned long addr)
-{
- return kern_fetch_store_strlen(addr);
-}
-
-/*
- * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
- * with max length and relative data location.
- */
-static nokprobe_inline int
-fetch_store_string_user(unsigned long addr, void *dest, void *base)
-{
- return kern_fetch_store_string_user(addr, dest, base);
-}
-
-/*
- * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
- * length and relative data location.
- */
-static nokprobe_inline int
-fetch_store_string(unsigned long addr, void *dest, void *base)
-{
- return kern_fetch_store_string(addr, dest, base);
-}
-
-static nokprobe_inline int
-probe_mem_read_user(void *dest, void *src, size_t size)
-{
- const void __user *uaddr = (__force const void __user *)src;
-
- return copy_from_user_nofault(dest, uaddr, size);
-}
-
-static nokprobe_inline int
-probe_mem_read(void *dest, void *src, size_t size)
-{
-#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
- if ((unsigned long)src < TASK_SIZE)
- return probe_mem_read_user(dest, src, size);
-#endif
- return copy_from_kernel_nofault(dest, src, size);
-}
-
/* eprobe handler */
static inline void
__eprobe_trace_func(struct eprobe_data *edata, void *rec)
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index e310052dc83c..7460f18ba973 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -18,6 +18,7 @@
#include <linux/trace_events.h>
#include <trace/events/mmflags.h>
#include "trace_probe.h"
+#include "trace_probe_tmpl.h"
#include "trace_probe_kernel.h"
#include "trace_synth.h"
@@ -420,12 +421,12 @@ static unsigned int trace_string(struct synth_trace_event *entry,
data_offset += event->n_u64 * sizeof(u64);
data_offset += data_size;
- len = kern_fetch_store_strlen((unsigned long)str_val);
+ len = fetch_store_strlen((unsigned long)str_val);
data_offset |= len << 16;
*(u32 *)&entry->fields[*n_u64] = data_offset;
- ret = kern_fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);
+ ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);
(*n_u64)++;
} else {
@@ -473,7 +474,7 @@ static notrace void trace_event_raw_event_synth(void *__data,
val_idx = var_ref_idx[field_pos];
str_val = (char *)(long)var_ref_vals[val_idx];
- len = kern_fetch_store_strlen((unsigned long)str_val);
+ len = fetch_store_strlen((unsigned long)str_val);
fields_size += len;
}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index a4ffa864dbb7..c2e0b741ae82 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1218,108 +1218,6 @@ static const struct file_operations kprobe_profile_ops = {
.release = seq_release,
};
-/* Kprobe specific fetch functions */
-
-/* Return the length of string -- including null terminal byte */
-static nokprobe_inline int
-fetch_store_strlen_user(unsigned long addr)
-{
- return kern_fetch_store_strlen_user(addr);
-}
-
-/* Return the length of string -- including null terminal byte */
-static nokprobe_inline int
-fetch_store_strlen(unsigned long addr)
-{
- return kern_fetch_store_strlen(addr);
-}
-
-/*
- * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
- * with max length and relative data location.
- */
-static nokprobe_inline int
-fetch_store_string_user(unsigned long addr, void *dest, void *base)
-{
- return kern_fetch_store_string_user(addr, dest, base);
-}
-
-/*
- * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
- * length and relative data location.
- */
-static nokprobe_inline int
-fetch_store_string(unsigned long addr, void *dest, void *base)
-{
- return kern_fetch_store_string(addr, dest, base);
-}
-
-static nokprobe_inline int
-probe_mem_read_user(void *dest, void *src, size_t size)
-{
- const void __user *uaddr = (__force const void __user *)src;
-
- return copy_from_user_nofault(dest, uaddr, size);
-}
-
-static nokprobe_inline int
-probe_mem_read(void *dest, void *src, size_t size)
-{
-#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
- if ((unsigned long)src < TASK_SIZE)
- return probe_mem_read_user(dest, src, size);
-#endif
- return copy_from_kernel_nofault(dest, src, size);
-}
-
-/* Note that we don't verify it, since the code does not come from user space */
-static int
-process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
- void *base)
-{
- struct pt_regs *regs = rec;
- unsigned long val;
-
-retry:
- /* 1st stage: get value from context */
- switch (code->op) {
- case FETCH_OP_REG:
- val = regs_get_register(regs, code->param);
- break;
- case FETCH_OP_STACK:
- val = regs_get_kernel_stack_nth(regs, code->param);
- break;
- case FETCH_OP_STACKP:
- val = kernel_stack_pointer(regs);
- break;
- case FETCH_OP_RETVAL:
- val = regs_return_value(regs);
- break;
- case FETCH_OP_IMM:
- val = code->immediate;
- break;
- case FETCH_OP_COMM:
- val = (unsigned long)current->comm;
- break;
- case FETCH_OP_DATA:
- val = (unsigned long)code->data;
- break;
-#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
- case FETCH_OP_ARG:
- val = regs_get_kernel_argument(regs, code->param);
- break;
-#endif
- case FETCH_NOP_SYMBOL: /* Ignore a place holder */
- code++;
- goto retry;
- default:
- return -EILSEQ;
- }
- code++;
-
- return process_fetch_insn_bottom(code, val, dest, base);
-}
-NOKPROBE_SYMBOL(process_fetch_insn)
/* Kprobe handler */
static nokprobe_inline void
diff --git a/kernel/trace/trace_probe_kernel.h b/kernel/trace/trace_probe_kernel.h
index 77dbd9ff9782..cee6078b1043 100644
--- a/kernel/trace/trace_probe_kernel.h
+++ b/kernel/trace/trace_probe_kernel.h
@@ -12,7 +12,7 @@
*/
/* Return the length of string -- including null terminal byte */
static nokprobe_inline int
-kern_fetch_store_strlen_user(unsigned long addr)
+fetch_store_strlen_user(unsigned long addr)
{
const void __user *uaddr = (__force const void __user *)addr;
int ret;
@@ -29,14 +29,14 @@ kern_fetch_store_strlen_user(unsigned long addr)
/* Return the length of string -- including null terminal byte */
static nokprobe_inline int
-kern_fetch_store_strlen(unsigned long addr)
+fetch_store_strlen(unsigned long addr)
{
int ret, len = 0;
u8 c;
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
if (addr < TASK_SIZE)
- return kern_fetch_store_strlen_user(addr);
+ return fetch_store_strlen_user(addr);
#endif
do {
@@ -63,7 +63,7 @@ static nokprobe_inline void set_data_loc(int ret, void *dest, void *__dest, void
* with max length and relative data location.
*/
static nokprobe_inline int
-kern_fetch_store_string_user(unsigned long addr, void *dest, void *base)
+fetch_store_string_user(unsigned long addr, void *dest, void *base)
{
const void __user *uaddr = (__force const void __user *)addr;
int maxlen = get_loc_len(*(u32 *)dest);
@@ -86,7 +86,7 @@ kern_fetch_store_string_user(unsigned long addr, void *dest, void *base)
* length and relative data location.
*/
static nokprobe_inline int
-kern_fetch_store_string(unsigned long addr, void *dest, void *base)
+fetch_store_string(unsigned long addr, void *dest, void *base)
{
int maxlen = get_loc_len(*(u32 *)dest);
void *__dest;
@@ -94,7 +94,7 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base)
#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
if ((unsigned long)addr < TASK_SIZE)
- return kern_fetch_store_string_user(addr, dest, base);
+ return fetch_store_string_user(addr, dest, base);
#endif
if (unlikely(!maxlen))
@@ -112,4 +112,132 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base)
return ret;
}
+static nokprobe_inline int
+probe_mem_read_user(void *dest, void *src, size_t size)
+{
+ const void __user *uaddr = (__force const void __user *)src;
+
+ return copy_from_user_nofault(dest, uaddr, size);
+}
+
+static nokprobe_inline int
+probe_mem_read(void *dest, void *src, size_t size)
+{
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+ if ((unsigned long)src < TASK_SIZE)
+ return probe_mem_read_user(dest, src, size);
+#endif
+ return copy_from_kernel_nofault(dest, src, size);
+}
+
+static unsigned long get_event_field(struct fetch_insn *code, void *rec)
+{
+ struct ftrace_event_field *field = code->data;
+ unsigned long val;
+ void *addr;
+
+ addr = rec + field->offset;
+
+ if (is_string_field(field)) {
+ switch (field->filter_type) {
+ case FILTER_DYN_STRING:
+ val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
+ break;
+ case FILTER_RDYN_STRING:
+ val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
+ break;
+ case FILTER_STATIC_STRING:
+ val = (unsigned long)addr;
+ break;
+ case FILTER_PTR_STRING:
+ val = (unsigned long)(*(char *)addr);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return 0;
+ }
+ return val;
+ }
+
+ switch (field->size) {
+ case 1:
+ if (field->is_signed)
+ val = *(char *)addr;
+ else
+ val = *(unsigned char *)addr;
+ break;
+ case 2:
+ if (field->is_signed)
+ val = *(short *)addr;
+ else
+ val = *(unsigned short *)addr;
+ break;
+ case 4:
+ if (field->is_signed)
+ val = *(int *)addr;
+ else
+ val = *(unsigned int *)addr;
+ break;
+ default:
+ if (field->is_signed)
+ val = *(long *)addr;
+ else
+ val = *(unsigned long *)addr;
+ break;
+ }
+ return val;
+}
+
+/* Note that we don't verify it, since the code does not come from user space */
+static int
+process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
+ void *base)
+{
+ struct pt_regs *regs = rec;
+ unsigned long val;
+
+retry:
+ /* 1st stage: get value from context */
+ switch (code->op) {
+ case FETCH_OP_REG:
+ val = regs_get_register(regs, code->param);
+ break;
+ case FETCH_OP_STACK:
+ val = regs_get_kernel_stack_nth(regs, code->param);
+ break;
+ case FETCH_OP_STACKP:
+ val = kernel_stack_pointer(regs);
+ break;
+ case FETCH_OP_RETVAL:
+ val = regs_return_value(regs);
+ break;
+ case FETCH_OP_IMM:
+ val = code->immediate;
+ break;
+ case FETCH_OP_COMM:
+ val = (unsigned long)current->comm;
+ break;
+ case FETCH_OP_DATA:
+ val = (unsigned long)code->data;
+ break;
+#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
+ case FETCH_OP_ARG:
+ val = regs_get_kernel_argument(regs, code->param);
+ break;
+#endif
+ case FETCH_NOP_SYMBOL: /* Ignore a place holder */
+ code++;
+ goto retry;
+ case FETCH_OP_TP_ARG:
+ val = get_event_field(code, rec);
+ break;
+ default:
+ return -EILSEQ;
+ }
+ code++;
+
+ return process_fetch_insn_bottom(code, val, dest, base);
+}
+NOKPROBE_SYMBOL(process_fetch_insn)
+
#endif /* __TRACE_PROBE_KERNEL_H_ */
--
2.25.1
Hi Song,
On Wed, 23 Nov 2022 16:02:04 +0800
Song Chen <[email protected]> wrote:
> There are 7 function definitions in trace_probe_tmpl.h, they are:
>
> 1, process_fetch_insn
> 2, fetch_store_strlen
> 3, fetch_store_string
> 4, fetch_store_strlen_user
> 5, fetch_store_string_user
> 6, probe_mem_read
> 7, probe_mem_read_user
>
> Every C file which includes trace_probe_tmpl.h has to implement them,
> otherwise it gets warnings and errors. However, some of them are identical,
> like kprobe and eprobe, as a result, there is a lot redundant code in those
> 2 files.
Thank you for update! this direction looks good to me.
>
> This patch would like to provide default behaviors for those functions
> which kprobe and eprobe can share by just including trace_probe_kernel.h
> with trace_probe_tmpl.h together.
>
> It removes redundant code, increases readability, and more importantly,
> makes it easier to introduce a new feature based on trace probe
> (it's possible).
OK, I have some comments, see below;
>
> Signed-off-by: Song Chen <[email protected]>
> ---
> kernel/trace/trace_eprobe.c | 144 ------------------------------
> kernel/trace/trace_events_synth.c | 7 +-
> kernel/trace/trace_kprobe.c | 102 ---------------------
> kernel/trace/trace_probe_kernel.h | 140 +++++++++++++++++++++++++++--
> 4 files changed, 138 insertions(+), 255 deletions(-)
>
> diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
> index bdb26eee7a0c..60ced4a7a25d 100644
> --- a/kernel/trace/trace_eprobe.c
> +++ b/kernel/trace/trace_eprobe.c
> @@ -319,64 +319,6 @@ print_eprobe_event(struct trace_iterator *iter, int flags,
> return trace_handle_return(s);
> }
>
> -static unsigned long get_event_field(struct fetch_insn *code, void *rec)
> -{
> - struct ftrace_event_field *field = code->data;
> - unsigned long val;
> - void *addr;
> -
> - addr = rec + field->offset;
> -
> - if (is_string_field(field)) {
> - switch (field->filter_type) {
> - case FILTER_DYN_STRING:
> - val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
> - break;
> - case FILTER_RDYN_STRING:
> - val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
> - break;
> - case FILTER_STATIC_STRING:
> - val = (unsigned long)addr;
> - break;
> - case FILTER_PTR_STRING:
> - val = (unsigned long)(*(char *)addr);
> - break;
> - default:
> - WARN_ON_ONCE(1);
> - return 0;
> - }
> - return val;
> - }
> -
> - switch (field->size) {
> - case 1:
> - if (field->is_signed)
> - val = *(char *)addr;
> - else
> - val = *(unsigned char *)addr;
> - break;
> - case 2:
> - if (field->is_signed)
> - val = *(short *)addr;
> - else
> - val = *(unsigned short *)addr;
> - break;
> - case 4:
> - if (field->is_signed)
> - val = *(int *)addr;
> - else
> - val = *(unsigned int *)addr;
> - break;
> - default:
> - if (field->is_signed)
> - val = *(long *)addr;
> - else
> - val = *(unsigned long *)addr;
> - break;
> - }
> - return val;
> -}
> -
> static int get_eprobe_size(struct trace_probe *tp, void *rec)
> {
> struct fetch_insn *code;
> @@ -419,92 +361,6 @@ static int get_eprobe_size(struct trace_probe *tp, void *rec)
> return ret;
> }
>
> -/* Kprobe specific fetch functions */
> -
> -/* Note that we don't verify it, since the code does not come from user space */
> -static int
> -process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
> - void *base)
> -{
> - unsigned long val;
> -
> - retry:
> - switch (code->op) {
> - case FETCH_OP_TP_ARG:
> - val = get_event_field(code, rec);
> - break;
> - case FETCH_OP_IMM:
> - val = code->immediate;
> - break;
> - case FETCH_OP_COMM:
> - val = (unsigned long)current->comm;
> - break;
> - case FETCH_OP_DATA:
> - val = (unsigned long)code->data;
> - break;
> - case FETCH_NOP_SYMBOL: /* Ignore a place holder */
> - code++;
> - goto retry;
> - default:
> - return -EILSEQ;
> - }
> - code++;
> - return process_fetch_insn_bottom(code, val, dest, base);
> -}
> -NOKPROBE_SYMBOL(process_fetch_insn)
> -
> -/* Return the length of string -- including null terminal byte */
> -static nokprobe_inline int
> -fetch_store_strlen_user(unsigned long addr)
> -{
> - return kern_fetch_store_strlen_user(addr);
> -}
> -
> -/* Return the length of string -- including null terminal byte */
> -static nokprobe_inline int
> -fetch_store_strlen(unsigned long addr)
> -{
> - return kern_fetch_store_strlen(addr);
> -}
> -
> -/*
> - * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
> - * with max length and relative data location.
> - */
> -static nokprobe_inline int
> -fetch_store_string_user(unsigned long addr, void *dest, void *base)
> -{
> - return kern_fetch_store_string_user(addr, dest, base);
> -}
> -
> -/*
> - * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
> - * length and relative data location.
> - */
> -static nokprobe_inline int
> -fetch_store_string(unsigned long addr, void *dest, void *base)
> -{
> - return kern_fetch_store_string(addr, dest, base);
> -}
> -
> -static nokprobe_inline int
> -probe_mem_read_user(void *dest, void *src, size_t size)
> -{
> - const void __user *uaddr = (__force const void __user *)src;
> -
> - return copy_from_user_nofault(dest, uaddr, size);
> -}
> -
> -static nokprobe_inline int
> -probe_mem_read(void *dest, void *src, size_t size)
> -{
> -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
> - if ((unsigned long)src < TASK_SIZE)
> - return probe_mem_read_user(dest, src, size);
> -#endif
> - return copy_from_kernel_nofault(dest, src, size);
> -}
> -
> /* eprobe handler */
> static inline void
> __eprobe_trace_func(struct eprobe_data *edata, void *rec)
> diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
> index e310052dc83c..7460f18ba973 100644
> --- a/kernel/trace/trace_events_synth.c
> +++ b/kernel/trace/trace_events_synth.c
> @@ -18,6 +18,7 @@
> #include <linux/trace_events.h>
> #include <trace/events/mmflags.h>
> #include "trace_probe.h"
> +#include "trace_probe_tmpl.h"
> #include "trace_probe_kernel.h"
>
> #include "trace_synth.h"
> @@ -420,12 +421,12 @@ static unsigned int trace_string(struct synth_trace_event *entry,
> data_offset += event->n_u64 * sizeof(u64);
> data_offset += data_size;
>
> - len = kern_fetch_store_strlen((unsigned long)str_val);
> + len = fetch_store_strlen((unsigned long)str_val);
>
> data_offset |= len << 16;
> *(u32 *)&entry->fields[*n_u64] = data_offset;
>
> - ret = kern_fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);
> + ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);
>
> (*n_u64)++;
> } else {
> @@ -473,7 +474,7 @@ static notrace void trace_event_raw_event_synth(void *__data,
> val_idx = var_ref_idx[field_pos];
> str_val = (char *)(long)var_ref_vals[val_idx];
>
> - len = kern_fetch_store_strlen((unsigned long)str_val);
> + len = fetch_store_strlen((unsigned long)str_val);
>
> fields_size += len;
> }
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index a4ffa864dbb7..c2e0b741ae82 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -1218,108 +1218,6 @@ static const struct file_operations kprobe_profile_ops = {
> .release = seq_release,
> };
>
> -/* Kprobe specific fetch functions */
> -
> -/* Return the length of string -- including null terminal byte */
> -static nokprobe_inline int
> -fetch_store_strlen_user(unsigned long addr)
> -{
> - return kern_fetch_store_strlen_user(addr);
> -}
> -
> -/* Return the length of string -- including null terminal byte */
> -static nokprobe_inline int
> -fetch_store_strlen(unsigned long addr)
> -{
> - return kern_fetch_store_strlen(addr);
> -}
> -
> -/*
> - * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
> - * with max length and relative data location.
> - */
> -static nokprobe_inline int
> -fetch_store_string_user(unsigned long addr, void *dest, void *base)
> -{
> - return kern_fetch_store_string_user(addr, dest, base);
> -}
> -
> -/*
> - * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
> - * length and relative data location.
> - */
> -static nokprobe_inline int
> -fetch_store_string(unsigned long addr, void *dest, void *base)
> -{
> - return kern_fetch_store_string(addr, dest, base);
> -}
> -
> -static nokprobe_inline int
> -probe_mem_read_user(void *dest, void *src, size_t size)
> -{
> - const void __user *uaddr = (__force const void __user *)src;
> -
> - return copy_from_user_nofault(dest, uaddr, size);
> -}
> -
> -static nokprobe_inline int
> -probe_mem_read(void *dest, void *src, size_t size)
> -{
> -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
> - if ((unsigned long)src < TASK_SIZE)
> - return probe_mem_read_user(dest, src, size);
> -#endif
> - return copy_from_kernel_nofault(dest, src, size);
> -}
> -
> -/* Note that we don't verify it, since the code does not come from user space */
> -static int
> -process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
> - void *base)
> -{
> - struct pt_regs *regs = rec;
> - unsigned long val;
> -
> -retry:
> - /* 1st stage: get value from context */
> - switch (code->op) {
> - case FETCH_OP_REG:
> - val = regs_get_register(regs, code->param);
> - break;
> - case FETCH_OP_STACK:
> - val = regs_get_kernel_stack_nth(regs, code->param);
> - break;
> - case FETCH_OP_STACKP:
> - val = kernel_stack_pointer(regs);
> - break;
> - case FETCH_OP_RETVAL:
> - val = regs_return_value(regs);
> - break;
> - case FETCH_OP_IMM:
> - val = code->immediate;
> - break;
> - case FETCH_OP_COMM:
> - val = (unsigned long)current->comm;
> - break;
> - case FETCH_OP_DATA:
> - val = (unsigned long)code->data;
> - break;
> -#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
> - case FETCH_OP_ARG:
> - val = regs_get_kernel_argument(regs, code->param);
> - break;
> -#endif
> - case FETCH_NOP_SYMBOL: /* Ignore a place holder */
> - code++;
> - goto retry;
> - default:
> - return -EILSEQ;
> - }
> - code++;
> -
> - return process_fetch_insn_bottom(code, val, dest, base);
> -}
> -NOKPROBE_SYMBOL(process_fetch_insn)
>
> /* Kprobe handler */
> static nokprobe_inline void
> diff --git a/kernel/trace/trace_probe_kernel.h b/kernel/trace/trace_probe_kernel.h
> index 77dbd9ff9782..cee6078b1043 100644
> --- a/kernel/trace/trace_probe_kernel.h
> +++ b/kernel/trace/trace_probe_kernel.h
OK, so for now, this header file is only for the kernel access events.
> @@ -12,7 +12,7 @@
> */
> /* Return the length of string -- including null terminal byte */
> static nokprobe_inline int
> -kern_fetch_store_strlen_user(unsigned long addr)
> +fetch_store_strlen_user(unsigned long addr)
> {
> const void __user *uaddr = (__force const void __user *)addr;
> int ret;
> @@ -29,14 +29,14 @@ kern_fetch_store_strlen_user(unsigned long addr)
>
> /* Return the length of string -- including null terminal byte */
> static nokprobe_inline int
> -kern_fetch_store_strlen(unsigned long addr)
> +fetch_store_strlen(unsigned long addr)
> {
> int ret, len = 0;
> u8 c;
>
> #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
> if (addr < TASK_SIZE)
> - return kern_fetch_store_strlen_user(addr);
> + return fetch_store_strlen_user(addr);
> #endif
>
> do {
> @@ -63,7 +63,7 @@ static nokprobe_inline void set_data_loc(int ret, void *dest, void *__dest, void
> * with max length and relative data location.
> */
> static nokprobe_inline int
> -kern_fetch_store_string_user(unsigned long addr, void *dest, void *base)
> +fetch_store_string_user(unsigned long addr, void *dest, void *base)
> {
> const void __user *uaddr = (__force const void __user *)addr;
> int maxlen = get_loc_len(*(u32 *)dest);
> @@ -86,7 +86,7 @@ kern_fetch_store_string_user(unsigned long addr, void *dest, void *base)
> * length and relative data location.
> */
> static nokprobe_inline int
> -kern_fetch_store_string(unsigned long addr, void *dest, void *base)
> +fetch_store_string(unsigned long addr, void *dest, void *base)
> {
> int maxlen = get_loc_len(*(u32 *)dest);
> void *__dest;
> @@ -94,7 +94,7 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base)
>
> #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
> if ((unsigned long)addr < TASK_SIZE)
> - return kern_fetch_store_string_user(addr, dest, base);
> + return fetch_store_string_user(addr, dest, base);
> #endif
>
> if (unlikely(!maxlen))
> @@ -112,4 +112,132 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base)
> return ret;
> }
>
> +static nokprobe_inline int
> +probe_mem_read_user(void *dest, void *src, size_t size)
> +{
> + const void __user *uaddr = (__force const void __user *)src;
> +
> + return copy_from_user_nofault(dest, uaddr, size);
> +}
> +
> +static nokprobe_inline int
> +probe_mem_read(void *dest, void *src, size_t size)
> +{
> +#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
> + if ((unsigned long)src < TASK_SIZE)
> + return probe_mem_read_user(dest, src, size);
> +#endif
> + return copy_from_kernel_nofault(dest, src, size);
> +}
> +
> +static unsigned long get_event_field(struct fetch_insn *code, void *rec)
Please make all functions as "nokprobe_inline" in trace_probe_kernel.h
because those can be used from kprobe context.
> +{
> + struct ftrace_event_field *field = code->data;
> + unsigned long val;
> + void *addr;
> +
> + addr = rec + field->offset;
> +
> + if (is_string_field(field)) {
> + switch (field->filter_type) {
> + case FILTER_DYN_STRING:
> + val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
> + break;
> + case FILTER_RDYN_STRING:
> + val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
> + break;
> + case FILTER_STATIC_STRING:
> + val = (unsigned long)addr;
> + break;
> + case FILTER_PTR_STRING:
> + val = (unsigned long)(*(char *)addr);
> + break;
> + default:
> + WARN_ON_ONCE(1);
> + return 0;
> + }
> + return val;
> + }
> +
> + switch (field->size) {
> + case 1:
> + if (field->is_signed)
> + val = *(char *)addr;
> + else
> + val = *(unsigned char *)addr;
> + break;
> + case 2:
> + if (field->is_signed)
> + val = *(short *)addr;
> + else
> + val = *(unsigned short *)addr;
> + break;
> + case 4:
> + if (field->is_signed)
> + val = *(int *)addr;
> + else
> + val = *(unsigned int *)addr;
> + break;
> + default:
> + if (field->is_signed)
> + val = *(long *)addr;
> + else
> + val = *(unsigned long *)addr;
> + break;
> + }
> + return val;
> +}
> +
> +/* Note that we don't verify it, since the code does not come from user space */
> +static int
Ditto.
> +process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
> + void *base)
> +{
> + struct pt_regs *regs = rec;
> + unsigned long val;
> +
> +retry:
> + /* 1st stage: get value from context */
> + switch (code->op) {
> + case FETCH_OP_REG:
> + val = regs_get_register(regs, code->param);
> + break;
> + case FETCH_OP_STACK:
> + val = regs_get_kernel_stack_nth(regs, code->param);
> + break;
> + case FETCH_OP_STACKP:
> + val = kernel_stack_pointer(regs);
> + break;
> + case FETCH_OP_RETVAL:
> + val = regs_return_value(regs);
> + break;
> + case FETCH_OP_IMM:
> + val = code->immediate;
> + break;
> + case FETCH_OP_COMM:
> + val = (unsigned long)current->comm;
> + break;
> + case FETCH_OP_DATA:
> + val = (unsigned long)code->data;
> + break;
> +#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
> + case FETCH_OP_ARG:
> + val = regs_get_kernel_argument(regs, code->param);
> + break;
> +#endif
> + case FETCH_NOP_SYMBOL: /* Ignore a place holder */
> + code++;
> + goto retry;
> + case FETCH_OP_TP_ARG:
> + val = get_event_field(code, rec);
> + break;
> + default:
> + return -EILSEQ;
> + }
> + code++;
> +
> + return process_fetch_insn_bottom(code, val, dest, base);
> +}
> +NOKPROBE_SYMBOL(process_fetch_insn)
And this is not needed for the nokprobe_inline functions.
Thank you!
> +
> #endif /* __TRACE_PROBE_KERNEL_H_ */
> --
> 2.25.1
>
--
Masami Hiramatsu (Google) <[email protected]>
Hi,
在 2022/11/25 08:29, Masami Hiramatsu (Google) 写道:
> Hi Song,
>
> On Wed, 23 Nov 2022 16:02:04 +0800
> Song Chen <[email protected]> wrote:
>
>> There are 7 function definitions in trace_probe_tmpl.h, they are:
>>
>> 1, process_fetch_insn
>> 2, fetch_store_strlen
>> 3, fetch_store_string
>> 4, fetch_store_strlen_user
>> 5, fetch_store_string_user
>> 6, probe_mem_read
>> 7, probe_mem_read_user
>>
>> Every C file which includes trace_probe_tmpl.h has to implement them,
>> otherwise it gets warnings and errors. However, some of them are identical,
>> like kprobe and eprobe, as a result, there is a lot redundant code in those
>> 2 files.
>
> Thank you for update! this direction looks good to me.
>
>>
>> This patch would like to provide default behaviors for those functions
>> which kprobe and eprobe can share by just including trace_probe_kernel.h
>> with trace_probe_tmpl.h together.
>>
>> It removes redundant code, increases readability, and more importantly,
>> makes it easier to introduce a new feature based on trace probe
>> (it's possible).
>
> OK, I have some comments, see below;
>
I looked into below comments, in summary, only mark nokprobe_inline for
get_event_field. is it correct?
/Song
>>
>> Signed-off-by: Song Chen <[email protected]>
>> ---
>> kernel/trace/trace_eprobe.c | 144 ------------------------------
>> kernel/trace/trace_events_synth.c | 7 +-
>> kernel/trace/trace_kprobe.c | 102 ---------------------
>> kernel/trace/trace_probe_kernel.h | 140 +++++++++++++++++++++++++++--
>> 4 files changed, 138 insertions(+), 255 deletions(-)
>>
>> diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
>> index bdb26eee7a0c..60ced4a7a25d 100644
>> --- a/kernel/trace/trace_eprobe.c
>> +++ b/kernel/trace/trace_eprobe.c
>> @@ -319,64 +319,6 @@ print_eprobe_event(struct trace_iterator *iter, int flags,
>> return trace_handle_return(s);
>> }
>>
>> -static unsigned long get_event_field(struct fetch_insn *code, void *rec)
>> -{
>> - struct ftrace_event_field *field = code->data;
>> - unsigned long val;
>> - void *addr;
>> -
>> - addr = rec + field->offset;
>> -
>> - if (is_string_field(field)) {
>> - switch (field->filter_type) {
>> - case FILTER_DYN_STRING:
>> - val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
>> - break;
>> - case FILTER_RDYN_STRING:
>> - val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
>> - break;
>> - case FILTER_STATIC_STRING:
>> - val = (unsigned long)addr;
>> - break;
>> - case FILTER_PTR_STRING:
>> - val = (unsigned long)(*(char *)addr);
>> - break;
>> - default:
>> - WARN_ON_ONCE(1);
>> - return 0;
>> - }
>> - return val;
>> - }
>> -
>> - switch (field->size) {
>> - case 1:
>> - if (field->is_signed)
>> - val = *(char *)addr;
>> - else
>> - val = *(unsigned char *)addr;
>> - break;
>> - case 2:
>> - if (field->is_signed)
>> - val = *(short *)addr;
>> - else
>> - val = *(unsigned short *)addr;
>> - break;
>> - case 4:
>> - if (field->is_signed)
>> - val = *(int *)addr;
>> - else
>> - val = *(unsigned int *)addr;
>> - break;
>> - default:
>> - if (field->is_signed)
>> - val = *(long *)addr;
>> - else
>> - val = *(unsigned long *)addr;
>> - break;
>> - }
>> - return val;
>> -}
>> -
>> static int get_eprobe_size(struct trace_probe *tp, void *rec)
>> {
>> struct fetch_insn *code;
>> @@ -419,92 +361,6 @@ static int get_eprobe_size(struct trace_probe *tp, void *rec)
>> return ret;
>> }
>>
>> -/* Kprobe specific fetch functions */
>> -
>> -/* Note that we don't verify it, since the code does not come from user space */
>> -static int
>> -process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
>> - void *base)
>> -{
>> - unsigned long val;
>> -
>> - retry:
>> - switch (code->op) {
>> - case FETCH_OP_TP_ARG:
>> - val = get_event_field(code, rec);
>> - break;
>> - case FETCH_OP_IMM:
>> - val = code->immediate;
>> - break;
>> - case FETCH_OP_COMM:
>> - val = (unsigned long)current->comm;
>> - break;
>> - case FETCH_OP_DATA:
>> - val = (unsigned long)code->data;
>> - break;
>> - case FETCH_NOP_SYMBOL: /* Ignore a place holder */
>> - code++;
>> - goto retry;
>> - default:
>> - return -EILSEQ;
>> - }
>> - code++;
>> - return process_fetch_insn_bottom(code, val, dest, base);
>> -}
>> -NOKPROBE_SYMBOL(process_fetch_insn)
>> -
>> -/* Return the length of string -- including null terminal byte */
>> -static nokprobe_inline int
>> -fetch_store_strlen_user(unsigned long addr)
>> -{
>> - return kern_fetch_store_strlen_user(addr);
>> -}
>> -
>> -/* Return the length of string -- including null terminal byte */
>> -static nokprobe_inline int
>> -fetch_store_strlen(unsigned long addr)
>> -{
>> - return kern_fetch_store_strlen(addr);
>> -}
>> -
>> -/*
>> - * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
>> - * with max length and relative data location.
>> - */
>> -static nokprobe_inline int
>> -fetch_store_string_user(unsigned long addr, void *dest, void *base)
>> -{
>> - return kern_fetch_store_string_user(addr, dest, base);
>> -}
>> -
>> -/*
>> - * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
>> - * length and relative data location.
>> - */
>> -static nokprobe_inline int
>> -fetch_store_string(unsigned long addr, void *dest, void *base)
>> -{
>> - return kern_fetch_store_string(addr, dest, base);
>> -}
>> -
>> -static nokprobe_inline int
>> -probe_mem_read_user(void *dest, void *src, size_t size)
>> -{
>> - const void __user *uaddr = (__force const void __user *)src;
>> -
>> - return copy_from_user_nofault(dest, uaddr, size);
>> -}
>> -
>> -static nokprobe_inline int
>> -probe_mem_read(void *dest, void *src, size_t size)
>> -{
>> -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>> - if ((unsigned long)src < TASK_SIZE)
>> - return probe_mem_read_user(dest, src, size);
>> -#endif
>> - return copy_from_kernel_nofault(dest, src, size);
>> -}
>> -
>> /* eprobe handler */
>> static inline void
>> __eprobe_trace_func(struct eprobe_data *edata, void *rec)
>> diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
>> index e310052dc83c..7460f18ba973 100644
>> --- a/kernel/trace/trace_events_synth.c
>> +++ b/kernel/trace/trace_events_synth.c
>> @@ -18,6 +18,7 @@
>> #include <linux/trace_events.h>
>> #include <trace/events/mmflags.h>
>> #include "trace_probe.h"
>> +#include "trace_probe_tmpl.h"
>> #include "trace_probe_kernel.h"
>>
>> #include "trace_synth.h"
>> @@ -420,12 +421,12 @@ static unsigned int trace_string(struct synth_trace_event *entry,
>> data_offset += event->n_u64 * sizeof(u64);
>> data_offset += data_size;
>>
>> - len = kern_fetch_store_strlen((unsigned long)str_val);
>> + len = fetch_store_strlen((unsigned long)str_val);
>>
>> data_offset |= len << 16;
>> *(u32 *)&entry->fields[*n_u64] = data_offset;
>>
>> - ret = kern_fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);
>> + ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry);
>>
>> (*n_u64)++;
>> } else {
>> @@ -473,7 +474,7 @@ static notrace void trace_event_raw_event_synth(void *__data,
>> val_idx = var_ref_idx[field_pos];
>> str_val = (char *)(long)var_ref_vals[val_idx];
>>
>> - len = kern_fetch_store_strlen((unsigned long)str_val);
>> + len = fetch_store_strlen((unsigned long)str_val);
>>
>> fields_size += len;
>> }
>> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
>> index a4ffa864dbb7..c2e0b741ae82 100644
>> --- a/kernel/trace/trace_kprobe.c
>> +++ b/kernel/trace/trace_kprobe.c
>> @@ -1218,108 +1218,6 @@ static const struct file_operations kprobe_profile_ops = {
>> .release = seq_release,
>> };
>>
>> -/* Kprobe specific fetch functions */
>> -
>> -/* Return the length of string -- including null terminal byte */
>> -static nokprobe_inline int
>> -fetch_store_strlen_user(unsigned long addr)
>> -{
>> - return kern_fetch_store_strlen_user(addr);
>> -}
>> -
>> -/* Return the length of string -- including null terminal byte */
>> -static nokprobe_inline int
>> -fetch_store_strlen(unsigned long addr)
>> -{
>> - return kern_fetch_store_strlen(addr);
>> -}
>> -
>> -/*
>> - * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
>> - * with max length and relative data location.
>> - */
>> -static nokprobe_inline int
>> -fetch_store_string_user(unsigned long addr, void *dest, void *base)
>> -{
>> - return kern_fetch_store_string_user(addr, dest, base);
>> -}
>> -
>> -/*
>> - * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
>> - * length and relative data location.
>> - */
>> -static nokprobe_inline int
>> -fetch_store_string(unsigned long addr, void *dest, void *base)
>> -{
>> - return kern_fetch_store_string(addr, dest, base);
>> -}
>> -
>> -static nokprobe_inline int
>> -probe_mem_read_user(void *dest, void *src, size_t size)
>> -{
>> - const void __user *uaddr = (__force const void __user *)src;
>> -
>> - return copy_from_user_nofault(dest, uaddr, size);
>> -}
>> -
>> -static nokprobe_inline int
>> -probe_mem_read(void *dest, void *src, size_t size)
>> -{
>> -#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>> - if ((unsigned long)src < TASK_SIZE)
>> - return probe_mem_read_user(dest, src, size);
>> -#endif
>> - return copy_from_kernel_nofault(dest, src, size);
>> -}
>> -
>> -/* Note that we don't verify it, since the code does not come from user space */
>> -static int
>> -process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
>> - void *base)
>> -{
>> - struct pt_regs *regs = rec;
>> - unsigned long val;
>> -
>> -retry:
>> - /* 1st stage: get value from context */
>> - switch (code->op) {
>> - case FETCH_OP_REG:
>> - val = regs_get_register(regs, code->param);
>> - break;
>> - case FETCH_OP_STACK:
>> - val = regs_get_kernel_stack_nth(regs, code->param);
>> - break;
>> - case FETCH_OP_STACKP:
>> - val = kernel_stack_pointer(regs);
>> - break;
>> - case FETCH_OP_RETVAL:
>> - val = regs_return_value(regs);
>> - break;
>> - case FETCH_OP_IMM:
>> - val = code->immediate;
>> - break;
>> - case FETCH_OP_COMM:
>> - val = (unsigned long)current->comm;
>> - break;
>> - case FETCH_OP_DATA:
>> - val = (unsigned long)code->data;
>> - break;
>> -#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
>> - case FETCH_OP_ARG:
>> - val = regs_get_kernel_argument(regs, code->param);
>> - break;
>> -#endif
>> - case FETCH_NOP_SYMBOL: /* Ignore a place holder */
>> - code++;
>> - goto retry;
>> - default:
>> - return -EILSEQ;
>> - }
>> - code++;
>> -
>> - return process_fetch_insn_bottom(code, val, dest, base);
>> -}
>> -NOKPROBE_SYMBOL(process_fetch_insn)
>>
>> /* Kprobe handler */
>> static nokprobe_inline void
>> diff --git a/kernel/trace/trace_probe_kernel.h b/kernel/trace/trace_probe_kernel.h
>> index 77dbd9ff9782..cee6078b1043 100644
>> --- a/kernel/trace/trace_probe_kernel.h
>> +++ b/kernel/trace/trace_probe_kernel.h
>
> OK, so for now, this header file is only for the kernel access events.
>
>> @@ -12,7 +12,7 @@
>> */
>> /* Return the length of string -- including null terminal byte */
>> static nokprobe_inline int
>> -kern_fetch_store_strlen_user(unsigned long addr)
>> +fetch_store_strlen_user(unsigned long addr)
>> {
>> const void __user *uaddr = (__force const void __user *)addr;
>> int ret;
>> @@ -29,14 +29,14 @@ kern_fetch_store_strlen_user(unsigned long addr)
>>
>> /* Return the length of string -- including null terminal byte */
>> static nokprobe_inline int
>> -kern_fetch_store_strlen(unsigned long addr)
>> +fetch_store_strlen(unsigned long addr)
>> {
>> int ret, len = 0;
>> u8 c;
>>
>> #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>> if (addr < TASK_SIZE)
>> - return kern_fetch_store_strlen_user(addr);
>> + return fetch_store_strlen_user(addr);
>> #endif
>>
>> do {
>> @@ -63,7 +63,7 @@ static nokprobe_inline void set_data_loc(int ret, void *dest, void *__dest, void
>> * with max length and relative data location.
>> */
>> static nokprobe_inline int
>> -kern_fetch_store_string_user(unsigned long addr, void *dest, void *base)
>> +fetch_store_string_user(unsigned long addr, void *dest, void *base)
>> {
>> const void __user *uaddr = (__force const void __user *)addr;
>> int maxlen = get_loc_len(*(u32 *)dest);
>> @@ -86,7 +86,7 @@ kern_fetch_store_string_user(unsigned long addr, void *dest, void *base)
>> * length and relative data location.
>> */
>> static nokprobe_inline int
>> -kern_fetch_store_string(unsigned long addr, void *dest, void *base)
>> +fetch_store_string(unsigned long addr, void *dest, void *base)
>> {
>> int maxlen = get_loc_len(*(u32 *)dest);
>> void *__dest;
>> @@ -94,7 +94,7 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base)
>>
>> #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>> if ((unsigned long)addr < TASK_SIZE)
>> - return kern_fetch_store_string_user(addr, dest, base);
>> + return fetch_store_string_user(addr, dest, base);
>> #endif
>>
>> if (unlikely(!maxlen))
>> @@ -112,4 +112,132 @@ kern_fetch_store_string(unsigned long addr, void *dest, void *base)
>> return ret;
>> }
>>
>> +static nokprobe_inline int
>> +probe_mem_read_user(void *dest, void *src, size_t size)
>> +{
>> + const void __user *uaddr = (__force const void __user *)src;
>> +
>> + return copy_from_user_nofault(dest, uaddr, size);
>> +}
>> +
>> +static nokprobe_inline int
>> +probe_mem_read(void *dest, void *src, size_t size)
>> +{
>> +#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
>> + if ((unsigned long)src < TASK_SIZE)
>> + return probe_mem_read_user(dest, src, size);
>> +#endif
>> + return copy_from_kernel_nofault(dest, src, size);
>> +}
>> +
>> +static unsigned long get_event_field(struct fetch_insn *code, void *rec)
>
> Please make all functions as "nokprobe_inline" in trace_probe_kernel.h
> because those can be used from kprobe context.
>
>
>> +{
>> + struct ftrace_event_field *field = code->data;
>> + unsigned long val;
>> + void *addr;
>> +
>> + addr = rec + field->offset;
>> +
>> + if (is_string_field(field)) {
>> + switch (field->filter_type) {
>> + case FILTER_DYN_STRING:
>> + val = (unsigned long)(rec + (*(unsigned int *)addr & 0xffff));
>> + break;
>> + case FILTER_RDYN_STRING:
>> + val = (unsigned long)(addr + (*(unsigned int *)addr & 0xffff));
>> + break;
>> + case FILTER_STATIC_STRING:
>> + val = (unsigned long)addr;
>> + break;
>> + case FILTER_PTR_STRING:
>> + val = (unsigned long)(*(char *)addr);
>> + break;
>> + default:
>> + WARN_ON_ONCE(1);
>> + return 0;
>> + }
>> + return val;
>> + }
>> +
>> + switch (field->size) {
>> + case 1:
>> + if (field->is_signed)
>> + val = *(char *)addr;
>> + else
>> + val = *(unsigned char *)addr;
>> + break;
>> + case 2:
>> + if (field->is_signed)
>> + val = *(short *)addr;
>> + else
>> + val = *(unsigned short *)addr;
>> + break;
>> + case 4:
>> + if (field->is_signed)
>> + val = *(int *)addr;
>> + else
>> + val = *(unsigned int *)addr;
>> + break;
>> + default:
>> + if (field->is_signed)
>> + val = *(long *)addr;
>> + else
>> + val = *(unsigned long *)addr;
>> + break;
>> + }
>> + return val;
>> +}
>> +
>> +/* Note that we don't verify it, since the code does not come from user space */
>> +static int
>
> Ditto.
>
>> +process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
>> + void *base)
>> +{
>> + struct pt_regs *regs = rec;
>> + unsigned long val;
>> +
>> +retry:
>> + /* 1st stage: get value from context */
>> + switch (code->op) {
>> + case FETCH_OP_REG:
>> + val = regs_get_register(regs, code->param);
>> + break;
>> + case FETCH_OP_STACK:
>> + val = regs_get_kernel_stack_nth(regs, code->param);
>> + break;
>> + case FETCH_OP_STACKP:
>> + val = kernel_stack_pointer(regs);
>> + break;
>> + case FETCH_OP_RETVAL:
>> + val = regs_return_value(regs);
>> + break;
>> + case FETCH_OP_IMM:
>> + val = code->immediate;
>> + break;
>> + case FETCH_OP_COMM:
>> + val = (unsigned long)current->comm;
>> + break;
>> + case FETCH_OP_DATA:
>> + val = (unsigned long)code->data;
>> + break;
>> +#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
>> + case FETCH_OP_ARG:
>> + val = regs_get_kernel_argument(regs, code->param);
>> + break;
>> +#endif
>> + case FETCH_NOP_SYMBOL: /* Ignore a place holder */
>> + code++;
>> + goto retry;
>> + case FETCH_OP_TP_ARG:
>> + val = get_event_field(code, rec);
>> + break;
>> + default:
>> + return -EILSEQ;
>> + }
>> + code++;
>> +
>> + return process_fetch_insn_bottom(code, val, dest, base);
>> +}
>> +NOKPROBE_SYMBOL(process_fetch_insn)
>
> And this is not needed for the nokprobe_inline functions.
>
> Thank you!
>
>> +
>> #endif /* __TRACE_PROBE_KERNEL_H_ */
>> --
>> 2.25.1
>>
>
>
Hi Song,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v6.1-rc7 next-20221130]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Song-Chen/reorganize-trace_peobe_tmpl-h/20221124-144203
patch link: https://lore.kernel.org/r/1669190524-2894-1-git-send-email-chensong_2000%40189.cn
patch subject: [PATCH v2 2/2] kernel/trace: Provide default impelentations defined in trace_probe_tmpl.h
config: hexagon-randconfig-r011-20221128
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 6e4cea55f0d1104408b26ac574566a0e4de48036)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/596b7db0e6685dbed21d4ae5c27492c1d12ab090
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Song-Chen/reorganize-trace_peobe_tmpl-h/20221124-144203
git checkout 596b7db0e6685dbed21d4ae5c27492c1d12ab090
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash kernel/trace/ net/smc/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
All errors (new ones prefixed by >>):
In file included from kernel/trace/trace_events_synth.c:18:
In file included from include/linux/trace_events.h:9:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/hexagon/include/asm/io.h:334:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __raw_readb(PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
#define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
^
In file included from kernel/trace/trace_events_synth.c:18:
In file included from include/linux/trace_events.h:9:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/hexagon/include/asm/io.h:334:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
#define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
^
In file included from kernel/trace/trace_events_synth.c:18:
In file included from include/linux/trace_events.h:9:
In file included from include/linux/hardirq.h:11:
In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/hexagon/include/asm/io.h:334:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writeb(value, PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
~~~~~~~~~~ ^
In file included from kernel/trace/trace_events_synth.c:22:
>> kernel/trace/trace_probe_kernel.h:203:9: error: call to undeclared function 'regs_get_register'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
val = regs_get_register(regs, code->param);
^
kernel/trace/trace_probe_kernel.h:203:9: note: did you mean 'kset_register'?
include/linux/kobject.h:180:25: note: 'kset_register' declared here
extern int __must_check kset_register(struct kset *kset);
^
In file included from kernel/trace/trace_events_synth.c:22:
>> kernel/trace/trace_probe_kernel.h:206:9: error: call to undeclared function 'regs_get_kernel_stack_nth'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
val = regs_get_kernel_stack_nth(regs, code->param);
^
>> kernel/trace/trace_probe_kernel.h:209:9: error: call to undeclared function 'kernel_stack_pointer'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
val = kernel_stack_pointer(regs);
^
>> kernel/trace/trace_probe_kernel.h:212:9: error: call to undeclared function 'regs_return_value'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
val = regs_return_value(regs);
^
6 warnings and 4 errors generated.
vim +/regs_get_register +203 kernel/trace/trace_probe_kernel.h
190
191 /* Note that we don't verify it, since the code does not come from user space */
192 static int
193 process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
194 void *base)
195 {
196 struct pt_regs *regs = rec;
197 unsigned long val;
198
199 retry:
200 /* 1st stage: get value from context */
201 switch (code->op) {
202 case FETCH_OP_REG:
> 203 val = regs_get_register(regs, code->param);
204 break;
205 case FETCH_OP_STACK:
> 206 val = regs_get_kernel_stack_nth(regs, code->param);
207 break;
208 case FETCH_OP_STACKP:
> 209 val = kernel_stack_pointer(regs);
210 break;
211 case FETCH_OP_RETVAL:
> 212 val = regs_return_value(regs);
213 break;
214 case FETCH_OP_IMM:
215 val = code->immediate;
216 break;
217 case FETCH_OP_COMM:
218 val = (unsigned long)current->comm;
219 break;
220 case FETCH_OP_DATA:
221 val = (unsigned long)code->data;
222 break;
223 #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
224 case FETCH_OP_ARG:
225 val = regs_get_kernel_argument(regs, code->param);
226 break;
227 #endif
228 case FETCH_NOP_SYMBOL: /* Ignore a place holder */
229 code++;
230 goto retry;
231 case FETCH_OP_TP_ARG:
232 val = get_event_field(code, rec);
233 break;
234 default:
235 return -EILSEQ;
236 }
237 code++;
238
239 return process_fetch_insn_bottom(code, val, dest, base);
240 }
241 NOKPROBE_SYMBOL(process_fetch_insn)
242
--
0-DAY CI Kernel Test Service
https://01.org/lkp