Em Fri, Jun 12, 2015 at 02:08:27PM +0900, Masami Hiramatsu escreveu:
> Fix to check both of non-exist symbols and kprobe blacklist symbols at
> symbol-map based converting too.
> 
> E.g. without this fix, perf-probe failes to write the event.
>   ----
>   # perf probe vfs_caches_init_early
>   Added new event:
>   Failed to write event: Invalid argument
>     Error: Failed to add events.
>   ----
> 
> This fixes it to catch the error before adding probes.
>   ----
>   # perf probe vfs_caches_init_early
>   vfs_caches_init_early is out of .text, skip it.
>     Error: Failed to add events.
>   ----

Not applying to my perf/core branch, maybe it needs the first patch in
this series, that is not applied so far?

- Arnaldo
 
> Signed-off-by: Masami Hiramatsu <masami.hiramatsu...@hitachi.com>
> ---
>  tools/perf/util/probe-event.c |  113 
> ++++++++++++++++++++++++++---------------
>  1 file changed, 71 insertions(+), 42 deletions(-)
> 
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index 7aa3efe..aa2479e 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -246,6 +246,20 @@ static void clear_probe_trace_events(struct 
> probe_trace_event *tevs, int ntevs)
>               clear_probe_trace_event(tevs + i);
>  }
>  
> +static bool kprobe_blacklist__listed(unsigned long address);
> +static bool kprobe_warn_out_range(const char *symbol, unsigned long address)
> +{
> +     /* Get the address of _etext for checking non-probable text symbol */
> +     if (kernel_get_symbol_address_by_name("_etext", false) < address)
> +             pr_warning("%s is out of .text, skip it.\n", symbol);
> +     else if (kprobe_blacklist__listed(address))
> +             pr_warning("%s is blacklisted function, skip it.\n", symbol);
> +     else
> +             return false;
> +
> +     return true;
> +}
> +
>  #ifdef HAVE_DWARF_SUPPORT
>  
>  static int kernel_get_module_dso(const char *module, struct dso **pdso)
> @@ -559,7 +573,6 @@ static int post_process_probe_trace_events(struct 
> probe_trace_event *tevs,
>                                          bool uprobe)
>  {
>       struct ref_reloc_sym *reloc_sym;
> -     u64 etext_addr;
>       char *tmp;
>       int i, skipped = 0;
>  
> @@ -575,31 +588,28 @@ static int post_process_probe_trace_events(struct 
> probe_trace_event *tevs,
>               pr_warning("Relocated base symbol is not found!\n");
>               return -EINVAL;
>       }
> -     /* Get the address of _etext for checking non-probable text symbol */
> -     etext_addr = kernel_get_symbol_address_by_name("_etext", false);
>  
>       for (i = 0; i < ntevs; i++) {
> -             if (tevs[i].point.address && !tevs[i].point.retprobe) {
> -                     /* If we found a wrong one, mark it by NULL symbol */
> -                     if (etext_addr < tevs[i].point.address) {
> -                             pr_warning("%s+%lu is out of .text, skip it.\n",
> -                                tevs[i].point.symbol, tevs[i].point.offset);
> -                             tmp = NULL;
> -                             skipped++;
> -                     } else {
> -                             tmp = strdup(reloc_sym->name);
> -                             if (!tmp)
> -                                     return -ENOMEM;
> -                     }
> -                     /* If we have no realname, use symbol for it */
> -                     if (!tevs[i].point.realname)
> -                             tevs[i].point.realname = tevs[i].point.symbol;
> -                     else
> -                             free(tevs[i].point.symbol);
> -                     tevs[i].point.symbol = tmp;
> -                     tevs[i].point.offset = tevs[i].point.address -
> -                                            reloc_sym->unrelocated_addr;
> +             if (!tevs[i].point.address || tevs[i].point.retprobe)
> +                     continue;
> +             /* If we found a wrong one, mark it by NULL symbol */
> +             if (kprobe_warn_out_range(tevs[i].point.symbol,
> +                                       tevs[i].point.address)) {
> +                     tmp = NULL;
> +                     skipped++;
> +             } else {
> +                     tmp = strdup(reloc_sym->name);
> +                     if (!tmp)
> +                             return -ENOMEM;
>               }
> +             /* If we have no realname, use symbol for it */
> +             if (!tevs[i].point.realname)
> +                     tevs[i].point.realname = tevs[i].point.symbol;
> +             else
> +                     free(tevs[i].point.symbol);
> +             tevs[i].point.symbol = tmp;
> +             tevs[i].point.offset = tevs[i].point.address -
> +                                    reloc_sym->unrelocated_addr;
>       }
>       return skipped;
>  }
> @@ -2126,6 +2136,27 @@ kprobe_blacklist__find_by_address(struct list_head 
> *blacklist,
>       return NULL;
>  }
>  
> +static LIST_HEAD(kprobe_blacklist);
> +
> +static void kprobe_blacklist__init(void)
> +{
> +     if (!list_empty(&kprobe_blacklist))
> +             return;
> +
> +     if (kprobe_blacklist__load(&kprobe_blacklist) < 0)
> +             pr_debug("No kprobe blacklist support, ignored\n");
> +}
> +
> +static void kprobe_blacklist__release(void)
> +{
> +     kprobe_blacklist__delete(&kprobe_blacklist);
> +}
> +
> +static bool kprobe_blacklist__listed(unsigned long address)
> +{
> +     return !!kprobe_blacklist__find_by_address(&kprobe_blacklist, address);
> +}
> +
>  static int perf_probe_event__sprintf(struct perf_probe_event *pev,
>                                    const char *module,
>                                    struct strbuf *result)
> @@ -2409,8 +2440,6 @@ static int __add_probe_trace_events(struct 
> perf_probe_event *pev,
>       char buf[64];
>       const char *event, *group;
>       struct strlist *namelist;
> -     LIST_HEAD(blacklist);
> -     struct kprobe_blacklist_node *node;
>       bool safename;
>  
>       if (pev->uprobes)
> @@ -2430,28 +2459,15 @@ static int __add_probe_trace_events(struct 
> perf_probe_event *pev,
>               ret = -ENOMEM;
>               goto close_out;
>       }
> -     /* Get kprobe blacklist if exists */
> -     if (!pev->uprobes) {
> -             ret = kprobe_blacklist__load(&blacklist);
> -             if (ret < 0)
> -                     pr_debug("No kprobe blacklist support, ignored\n");
> -     }
>  
>       safename = (pev->point.function && !strisglob(pev->point.function));
>       ret = 0;
>       pr_info("Added new event%s\n", (ntevs > 1) ? "s:" : ":");
>       for (i = 0; i < ntevs; i++) {
>               tev = &tevs[i];
> -             /* Skip if the symbol is out of .text (marked previously) */
> +             /* Skip if the symbol is out of .text or blacklisted */
>               if (!tev->point.symbol)
>                       continue;
> -             /* Ensure that the address is NOT blacklisted */
> -             node = kprobe_blacklist__find_by_address(&blacklist,
> -                                                      tev->point.address);
> -             if (node) {
> -                     pr_warning("Warning: Skipped probing on blacklisted 
> function: %s\n", node->symbol);
> -                     continue;
> -             }
>  
>               if (pev->event)
>                       event = pev->event;
> @@ -2513,7 +2529,6 @@ static int __add_probe_trace_events(struct 
> perf_probe_event *pev,
>                        tev->event);
>       }
>  
> -     kprobe_blacklist__delete(&blacklist);
>       strlist__delete(namelist);
>  close_out:
>       close(fd);
> @@ -2563,7 +2578,7 @@ static int find_probe_trace_events_from_map(struct 
> perf_probe_event *pev,
>       struct perf_probe_point *pp = &pev->point;
>       struct probe_trace_point *tp;
>       int num_matched_functions;
> -     int ret, i, j;
> +     int ret, i, j, skipped = 0;
>  
>       map = get_target_map(pev->target, pev->uprobes);
>       if (!map) {
> @@ -2631,7 +2646,12 @@ static int find_probe_trace_events_from_map(struct 
> perf_probe_event *pev,
>               }
>               /* Add one probe point */
>               tp->address = map->unmap_ip(map, sym->start) + pp->offset;
> -             if (reloc_sym) {
> +             /* If we found a wrong one, mark it by NULL symbol */
> +             if (!pev->uprobes &&
> +                 kprobe_warn_out_range(sym->name, tp->address)) {
> +                     tp->symbol = NULL;      /* Skip it */
> +                     skipped++;
> +             } else if (reloc_sym) {
>                       tp->symbol = strdup_or_goto(reloc_sym->name, nomem_out);
>                       tp->offset = tp->address - reloc_sym->addr;
>               } else {
> @@ -2667,6 +2687,10 @@ static int find_probe_trace_events_from_map(struct 
> perf_probe_event *pev,
>               }
>               arch__fix_tev_from_maps(pev, tev, map);
>       }
> +     if (ret == skipped) {
> +             ret = -ENOENT;
> +             goto err_out;
> +     }
>  
>  out:
>       put_target_map(map, pev->uprobes);
> @@ -2737,6 +2761,9 @@ int add_perf_probe_events(struct perf_probe_event 
> *pevs, int npevs)
>       /* Loop 1: convert all events */
>       for (i = 0; i < npevs; i++) {
>               pkgs[i].pev = &pevs[i];
> +             /* Init kprobe blacklist if needed */
> +             if (!pkgs[i].pev->uprobes)
> +                     kprobe_blacklist__init();
>               /* Convert with or without debuginfo */
>               ret  = convert_to_probe_trace_events(pkgs[i].pev,
>                                                    &pkgs[i].tevs);
> @@ -2744,6 +2771,8 @@ int add_perf_probe_events(struct perf_probe_event 
> *pevs, int npevs)
>                       goto end;
>               pkgs[i].ntevs = ret;
>       }
> +     /* This just release blacklist only if allocated */
> +     kprobe_blacklist__release();
>  
>       /* Loop 2: add all events */
>       for (i = 0; i < npevs; i++) {
> 
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