| Message ID | 1669190524-2894-1-git-send-email-chensong_2000@189.cn (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | reorganize trace_peobe_tmpl.h | expand |
Hi Song, On Wed, 23 Nov 2022 16:02:04 +0800 Song Chen <chensong_2000@189.cn> 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 <chensong_2000@189.cn> > --- > 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, 在 2022/11/25 08:29, Masami Hiramatsu (Google) 写道: > Hi Song, > > On Wed, 23 Nov 2022 16:02:04 +0800 > Song Chen <chensong_2000@189.cn> 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 <chensong_2000@189.cn> >> --- >> 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 <lkp@intel.com>
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
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_ */
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 <chensong_2000@189.cn> --- 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(-)