Recent perf-tools does not compile on alpha

Recent perf-tools does not compile on alpha

[matoro]

Hi!  Recent versions of the perf tools (5.19) do not compile on alpha 
with the following errors:

util/unwind-libdw.c: In function ‘memory_read’:
util/unwind-libdw.c:161:62: error: ‘PERF_REG_SP’ undeclared (first use 
in this function); did you mean ‘PERF_MEM_S’?
   161 |         ret = perf_reg_value(&start, &ui->sample->user_regs, 
PERF_REG_SP);
       |                                                              
^~~~~~~~~~~
       |                                                              
PERF_MEM_S
util/unwind-libdw.c:161:62: note: each undeclared identifier is reported 
only once for each function it appears in
util/unwind-libdw.c: In function ‘unwind__get_entries’:
util/unwind-libdw.c:255:53: error: ‘PERF_REG_IP’ undeclared (first use 
in this function); did you mean ‘PERF_REGS_MAX’?
   255 |         err = perf_reg_value(&ip, &data->user_regs, 
PERF_REG_IP);
       |                                                     ^~~~~~~~~~~
       |                                                     
PERF_REGS_MAX

Wondering if anybody has some pointers about where these definitions 
should be coming from on alpha?

Re: Recent perf-tools does not compile on alpha

[James Clark]

On 08/10/2022 04:53, matoro wrote:
> Hi!  Recent versions of the perf tools (5.19) do not compile on alpha
> with the following errors:
> 
> util/unwind-libdw.c: In function ‘memory_read’:
> util/unwind-libdw.c:161:62: error: ‘PERF_REG_SP’ undeclared (first use
> in this function); did you mean ‘PERF_MEM_S’?
>   161 |         ret = perf_reg_value(&start, &ui->sample->user_regs,
> PERF_REG_SP);
>       |                                                             
> ^~~~~~~~~~~
>       |                                                             
> PERF_MEM_S
> util/unwind-libdw.c:161:62: note: each undeclared identifier is reported
> only once for each function it appears in
> util/unwind-libdw.c: In function ‘unwind__get_entries’:
> util/unwind-libdw.c:255:53: error: ‘PERF_REG_IP’ undeclared (first use
> in this function); did you mean ‘PERF_REGS_MAX’?
>   255 |         err = perf_reg_value(&ip, &data->user_regs, PERF_REG_IP);
>       |                                                     ^~~~~~~~~~~
>       |                                                     PERF_REGS_MAX
> 
> Wondering if anybody has some pointers about where these definitions
> should be coming from on alpha?

Is CONFIG_LIBDW_DWARF_UNWIND being set in the autodetection when it
wasn't before? You can override it with NO_LIBDW_DWARF_UNWIND=1

Other than that, you'd have to add
linux/tools/perf/arch/alpha/include/perf_regs.h