From 9b960a38835fcaf977f20dcc34ce9e54ff9563bd Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Wed, 25 Apr 2018 21:19:59 +0900 Subject: [PATCH] tracing: probeevent: Unify fetch_insn processing common part Unify the fetch_insn bottom process (from stage 2: dereference indirect data) from kprobe and uprobe events, since those are mostly same. Link: http://lkml.kernel.org/r/152465879965.26224.8547240824606804815.stgit@devbox Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_kprobe.c | 47 +++++----------------------- kernel/trace/trace_probe_tmpl.h | 55 ++++++++++++++++++++++++++++++++- kernel/trace/trace_uprobe.c | 43 ++------------------------ 3 files changed, 63 insertions(+), 82 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 4895ca85ec79..fdd43f2f1fd1 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -899,13 +899,18 @@ fetch_store_string(unsigned long addr, void *dest, void *base) return ret; } +static nokprobe_inline int +probe_mem_read(void *dest, void *src, size_t size) +{ + return probe_kernel_read(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, struct pt_regs *regs, void *dest, void *base) { unsigned long val; - int ret = 0; /* 1st stage: get value from context */ switch (code->op) { @@ -932,45 +937,7 @@ process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, } code++; - /* 2nd stage: dereference memory if needed */ - while (code->op == FETCH_OP_DEREF) { - ret = probe_kernel_read(&val, (void *)val + code->offset, - sizeof(val)); - if (ret) - return ret; - code++; - } - - /* 3rd stage: store value to buffer */ - if (unlikely(!dest)) { - if (code->op == FETCH_OP_ST_STRING) - return fetch_store_strlen(val + code->offset); - else - return -EILSEQ; - } - - switch (code->op) { - case FETCH_OP_ST_RAW: - fetch_store_raw(val, code, dest); - break; - case FETCH_OP_ST_MEM: - probe_kernel_read(dest, (void *)val + code->offset, code->size); - break; - case FETCH_OP_ST_STRING: - ret = fetch_store_string(val + code->offset, dest, base); - break; - default: - return -EILSEQ; - } - code++; - - /* 4th stage: modify stored value if needed */ - if (code->op == FETCH_OP_MOD_BF) { - fetch_apply_bitfield(code, dest); - code++; - } - - return code->op == FETCH_OP_END ? ret : -EILSEQ; + return process_fetch_insn_bottom(code, val, dest, base); } NOKPROBE_SYMBOL(process_fetch_insn) diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h index 3b4aba6f84cc..b4075f3e3a29 100644 --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -49,13 +49,66 @@ fetch_apply_bitfield(struct fetch_insn *code, void *buf) } /* - * This must be defined for each callsite. + * These functions must be defined for each callsite. * Return consumed dynamic data size (>= 0), or error (< 0). * If dest is NULL, don't store result and return required dynamic data size. */ static int process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, void *base); +static nokprobe_inline int fetch_store_strlen(unsigned long addr); +static nokprobe_inline int +fetch_store_string(unsigned long addr, void *dest, void *base); +static nokprobe_inline int +probe_mem_read(void *dest, void *src, size_t size); + +/* From the 2nd stage, routine is same */ +static nokprobe_inline int +process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val, + void *dest, void *base) +{ + int ret = 0; + + /* 2nd stage: dereference memory if needed */ + while (code->op == FETCH_OP_DEREF) { + ret = probe_mem_read(&val, (void *)val + code->offset, + sizeof(val)); + if (ret) + return ret; + code++; + } + + /* 3rd stage: store value to buffer */ + if (unlikely(!dest)) { + if (code->op == FETCH_OP_ST_STRING) + return fetch_store_strlen(val + code->offset); + else + return -EILSEQ; + } + + switch (code->op) { + case FETCH_OP_ST_RAW: + fetch_store_raw(val, code, dest); + break; + case FETCH_OP_ST_MEM: + probe_mem_read(dest, (void *)val + code->offset, code->size); + break; + case FETCH_OP_ST_STRING: + ret = fetch_store_string(val + code->offset, dest, base); + break; + default: + return -EILSEQ; + } + code++; + + /* 4th stage: modify stored value if needed */ + if (code->op == FETCH_OP_MOD_BF) { + fetch_apply_bitfield(code, dest); + code++; + } + + return code->op == FETCH_OP_END ? ret : -EILSEQ; +} /* Sum up total data length for dynamic arraies (strings) */ static nokprobe_inline int diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 912cb2093944..7154473ffaa4 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -101,7 +101,7 @@ static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) * Uprobes-specific fetch functions */ static nokprobe_inline int -probe_user_read(void *dest, void *src, size_t size) +probe_mem_read(void *dest, void *src, size_t size) { void __user *vaddr = (void __force __user *)src; @@ -162,7 +162,6 @@ process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, void *base) { unsigned long val; - int ret = 0; /* 1st stage: get value from context */ switch (code->op) { @@ -189,45 +188,7 @@ process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest, } code++; - /* 2nd stage: dereference memory if needed */ - while (code->op == FETCH_OP_DEREF) { - ret = probe_user_read(&val, (void *)val + code->offset, - sizeof(val)); - if (ret) - return ret; - code++; - } - - /* 3rd stage: store value to buffer */ - if (unlikely(!dest)) { - if (code->op == FETCH_OP_ST_STRING) - return fetch_store_strlen(val + code->offset); - else - return -EILSEQ; - } - - switch (code->op) { - case FETCH_OP_ST_RAW: - fetch_store_raw(val, code, dest); - break; - case FETCH_OP_ST_MEM: - probe_kernel_read(dest, (void *)val + code->offset, code->size); - break; - case FETCH_OP_ST_STRING: - ret = fetch_store_string(val + code->offset, dest, base); - break; - default: - return -EILSEQ; - } - code++; - - /* 4th stage: modify stored value if needed */ - if (code->op == FETCH_OP_MOD_BF) { - fetch_apply_bitfield(code, dest); - code++; - } - - return code->op == FETCH_OP_END ? ret : -EILSEQ; + return process_fetch_insn_bottom(code, val, dest, base); } NOKPROBE_SYMBOL(process_fetch_insn) -- 2.20.1