Kernel build does not link in libgcc, which defines the function.
David
On Fri, Dec 21, 2012 at 8:31 AM, Teresa Johnson <tejohn...@google.com> wrote:
> On Wed, Dec 19, 2012 at 12:11 PM, Rong Xu <x...@google.com> wrote:
>> Hi,
>>
>> This patch updates the support for FDO build in linux kernel for gcc 4.7.
>> Tested with 2.6.34 kernel and google internal benchmarks.
>>
>> Thanks,
>>
>> -Rong
>>
>> 2012-12-19 Rong Xu <x...@google.com>
>>
>> * libgcc/libgcov.c
>> (gcov_counter_active): v4.7 kernel fdo support.
>> (crc32_unsigned): Include in GCOV_KERNEL build.
>> (gcov_alloc_filename): Remove from GCOV_KERNEL build.
>> (gcov_sort_icall_topn_counter): Ditto.
>> (gcov_dump_module_info): Ditto.
>> (gcov_compute_histogram): v4.7 kernel fdo support.
>> (gcov_merge_gcda_file): Ditto.
>> (gcov_gcda_file_size): Ditto.
>> (gcov_write_gcda_file): Ditto.
>> (__gcov_topn_value_profiler_body): Ditto.
>> (gcov_set_vfile): Ditto.
>> (gcov_kernel_dump_gcov_init): Ditto.
>> (gcov_kernel_dump_one_gcov): Ditto.
>> * gcc/gcov-io.c (gcov_read_string): Ditto.
>> (static int k_popcountll): Ditto.
>> (gcov_read_summary): Ditto.
>> (kernel_file_fclose): Ditto.
>> (kernel_file_ftell): Ditto.
>> (kernel_file_fwrite): Ditto.
>> * gcc/gcov-io.h (struct gcov_info): remove const keyword.
>>
>> Index: libgcc/libgcov.c
>> ===================================================================
>> --- libgcc/libgcov.c (revision 194562)
>> +++ libgcc/libgcov.c (working copy)
>> @@ -46,11 +46,11 @@ see the files COPYING3 and COPYING.RUNTIME respect
>> #include "tsystem.h"
>> #include "coretypes.h"
>> #include "tm.h"
>> -#endif /* __KERNEL__ */
>> #include "libgcc_tm.h"
>> #include "gthr.h"
>> +#endif /* __KERNEL__ */
>>
>> -#if 1
>> +#ifndef __KERNEL__
>> #define THREAD_PREFIX __thread
>> #else
>> #define THREAD_PREFIX
>> @@ -120,6 +120,7 @@ extern int gcov_dump_complete ATTRIBUTE_HIDDEN;
>> #ifdef L_gcov
>> #include "gcov-io.c"
>>
>> +#ifndef __GCOV_KERNEL__
>> /* Create a strong reference to these symbols so that they are
>> unconditionally pulled into the instrumented binary, even when
>> the only reference is a weak reference. This is necessary because
>> @@ -134,6 +135,7 @@ extern int gcov_dump_complete ATTRIBUTE_HIDDEN;
>> these symbols will always need to be resolved. */
>> void (*__gcov_dummy_ref1)() = &__gcov_reset;
>> void (*__gcov_dummy_ref2)() = &__gcov_dump;
>> +#endif /* __GCOV_KERNEL__ */
>>
>> /* Utility function for outputing errors. */
>> static int
>> @@ -151,6 +153,10 @@ gcov_error (const char *fmt, ...)
>> return ret;
>> }
>>
>> +/* A program checksum allows us to distinguish program data for an
>> + object file included in multiple programs. */
>> +static gcov_unsigned_t gcov_crc32;
>> +
>> #ifndef __GCOV_KERNEL__
>> /* Emitted in coverage.c. */
>> extern char * __gcov_pmu_profile_filename;
>> @@ -183,10 +189,6 @@ THREAD_PREFIX gcov_unsigned_t __gcov_sample_counte
>> /* Chain of per-object gcov structures. */
>> extern struct gcov_info *__gcov_list;
>>
>> -/* A program checksum allows us to distinguish program data for an
>> - object file included in multiple programs. */
>> -static gcov_unsigned_t gcov_crc32;
>> -
>> /* Size of the longest file name. */
>> static size_t gcov_max_filename = 0;
>>
>> @@ -323,8 +325,6 @@ gcov_counter_active (const struct gcov_info *info,
>> return (info->merge[type] != 0);
>> }
>>
>> -#ifndef __GCOV_KERNEL__
>> -
>> /* Add an unsigned value to the current crc */
>>
>> static gcov_unsigned_t
>> @@ -344,6 +344,8 @@ crc32_unsigned (gcov_unsigned_t crc32, gcov_unsign
>> return crc32;
>> }
>>
>> +#ifndef __GCOV_KERNEL__
>> +
>> /* Check if VERSION of the info block PTR matches libgcov one.
>> Return 1 on success, or zero in case of versions mismatch.
>> If FILENAME is not NULL, its value used for reporting purposes
>> @@ -464,6 +466,8 @@ gcov_alloc_filename (void)
>> gi_filename_up = gi_filename + prefix_length;
>> }
>>
>> +#endif /* __GCOV_KERNEL__ */
>> +
>> /* Sort N entries in VALUE_ARRAY in descending order.
>> Each entry in VALUE_ARRAY has two values. The sorting
>> is based on the second value. */
>> @@ -509,6 +513,8 @@ gcov_sort_icall_topn_counter (const struct gcov_ct
>> }
>> }
>>
>> +#ifndef __GCOV_KERNEL__
>> +
>> /* Write imported files (auxiliary modules) for primary module GI_PTR
>> into file GI_FILENAME. */
>>
>> @@ -586,6 +592,8 @@ gcov_dump_module_info (void)
>> __gcov_finalize_dyn_callgraph ();
>> }
>>
>> +#endif /* __GCOV_KERNEL__ */
>> +
>> /* Insert counter VALUE into HISTOGRAM. */
>>
>> static void
>> @@ -656,6 +664,8 @@ gcov_compute_histogram (struct gcov_summary *sum)
>> }
>> }
>>
>> +#ifndef __GCOV_KERNEL__
>> +
>> /* Dump the coverage counts. We merge with existing counts when
>> possible, to avoid growing the .da files ad infinitum. We use this
>> program's checksum to make sure we only accumulate whole program
>> @@ -1013,12 +1023,7 @@ gcov_merge_gcda_file (struct gcov_info *gi_ptr)
>> goto read_error;
>> }
>> if (tag && tag != GCOV_TAG_MODULE_INFO)
>> - {
>> - read_mismatch:;
>> - fprintf (stderr, "profiling:%s:Merge mismatch for %s\n",
>> - gi_filename, f_ix + 1 ? "function" : "summaries");
>> - goto read_fatal;
>> - }
>> + goto read_mismatch;
>> }
>> goto rewrite;
>>
>> @@ -1031,6 +1036,11 @@ read_error:;
>>
>> goto rewrite;
>>
>> +read_mismatch:;
>> + gcov_error ("profiling:%s:Merge mismatch for %s\n",
>> + gi_filename, f_ix + 1 ? "function" : "summaries");
>> + goto read_fatal;
>> +
>> read_fatal:;
>> gcov_close ();
>> return 1;
>> @@ -1076,7 +1086,7 @@ rewrite:;
>> sizeof (*cs_all) - (sizeof (gcov_bucket_type)
>> * GCOV_HISTOGRAM_SIZE)))
>> {
>> - fprintf (stderr, "profiling:%s:Invocation mismatch - "
>> + gcov_error ("profiling:%s:Invocation mismatch - "
>> "some data files may have been removed%s\n",
>> gi_filename, GCOV_LOCKED
>> ? "" : " or concurrent update without locking support");
>> @@ -1093,14 +1103,14 @@ rewrite:;
>> the size is in units of gcov_type. */
>>
>> GCOV_LINKAGE unsigned
>> -gcov_gcda_file_size (struct gcov_info *gi_ptr,
>> - struct gcov_summary *sum)
>> +gcov_gcda_file_size (struct gcov_info *gi_ptr)
>> {
>> unsigned size;
>> const struct gcov_fn_info *fi_ptr;
>> unsigned f_ix, t_ix, h_ix, h_cnt = 0;
>> unsigned n_counts;
>> const struct gcov_ctr_info *ci_ptr;
>> + struct gcov_summary *sum = &this_program;
>> const struct gcov_ctr_summary *csum;
>>
>> /* GCOV_DATA_MAGIC, GCOV_VERSION and time_stamp. */
>> @@ -1181,13 +1191,14 @@ gcov_write_gcda_file (struct gcov_info *gi_ptr)
>> ci_ptr = gfi_ptr->ctrs;
>> for (t_ix = 0; t_ix < GCOV_COUNTERS; t_ix++)
>> {
>> + gcov_type *c_ptr;
>> if (!gi_ptr->merge[t_ix])
>> continue;
>>
>> n_counts = ci_ptr->num;
>> gcov_write_tag_length (GCOV_TAG_FOR_COUNTER (t_ix),
>> GCOV_TAG_COUNTER_LENGTH (n_counts));
>> - gcov_type *c_ptr = ci_ptr->values;
>> + c_ptr = ci_ptr->values;
>> while (n_counts--)
>> gcov_write_counter (*c_ptr++);
>> ci_ptr++;
>> @@ -1692,7 +1703,7 @@ __gcov_topn_value_profiler_body (gcov_type *counte
>> {
>> unsigned i, j;
>> gcov_type *p, minv;
>> - gcov_type* tmp_cnts
>> + gcov_type* tmp_cnts
>> = (gcov_type *)alloca (topn_val * sizeof(gcov_type));
>>
>> *num_eviction = 0;
>> @@ -2050,15 +2061,20 @@ gcov_set_vfile (gcov_kernel_vfile *file)
>> gcov_current_file = file;
>> }
>>
>> +/* Init function before dumping the gcda file in kernel. */
>> +
>> +void
>> +gcov_kernel_dump_gcov_init (void)
>> +{
>> + gcov_exit_init ();
>> +}
>> +
>> /* Dump one entry in the gcov_info list (for one object) in kernel. */
>>
>> void
>> gcov_kernel_dump_one_gcov (struct gcov_info *info)
>> {
>> gcc_assert (gcov_current_file);
>> -
>> - gcov_exit_init ();
>> -
>> gcov_dump_one_gcov (info);
>> }
>>
>> Index: gcc/gcov-io.c
>> ===================================================================
>> --- gcc/gcov-io.c (revision 194562)
>> +++ gcc/gcov-io.c (working copy)
>> @@ -662,6 +662,30 @@ gcov_read_string (void)
>> return (const char *) gcov_read_words (length);
>> }
>>
>> +#ifdef __GCOV_KERNEL__
>> +static const unsigned char __popcount_tab[256] =
>> +{
>> + 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,
>> + 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
>> + 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
>> + 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
>> + 1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,
>> + 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
>> + 2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,6,3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,
>> + 3,4,4,5,4,5,5,6,4,5,5,6,5,6,6,7,4,5,5,6,5,6,6,7,5,6,6,7,6,7,7,8
>> +};
>> +
>> +static int k_popcountll (long long x)
>> +{
>> + int i, ret = 0;
>> +
>> + for (i = 0; i < 8*sizeof(long long) ; i += 8)
>> + ret += __popcount_tab[(x >> i) & 0xff];
>> +
>> + return ret;
>> +}
>> +#endif
>> +
>> GCOV_LINKAGE void
>> gcov_read_summary (struct gcov_summary *summary)
>> {
>> @@ -683,7 +707,11 @@ gcov_read_summary (struct gcov_summary *summary)
>> for (bv_ix = 0; bv_ix < GCOV_HISTOGRAM_BITVECTOR_SIZE; bv_ix++)
>> {
>> histo_bitvector[bv_ix] = gcov_read_unsigned ();
>> +#ifndef __GCOV_KERNEL__
>> h_cnt += __builtin_popcountll (histo_bitvector[bv_ix]);
>> +#else
>> + h_cnt += k_popcountll (histo_bitvector[bv_ix]);
>> +#endif
>
> Is the issue here that __builtin_popcountll is not available? I just
> committed a fix to trunk to deal with a similar issue, can you see if
> this would address the problem here too?
>
> http://gcc.gnu.org/ml/gcc-bugs/2012-12/msg01976.html
>
> Thanks,
> Teresa
>
>> }
>> bv_ix = 0;
>> h_ix = 0;
>> @@ -1137,7 +1165,6 @@ kernel_file_fclose (gcov_kernel_vfile *fp)
>> long
>> kernel_file_ftell (gcov_kernel_vfile *fp)
>> {
>> - gcc_assert (0); /* should not reach here */
>> return 0;
>> }
>>
>> @@ -1192,8 +1219,9 @@ kernel_file_fwrite (const void *ptr, size_t size,
>> if (vsize <= vpos)
>> {
>> printk (KERN_ERR
>> - "GCOV_KERNEL: something wrong: vbuf=%p vsize=%u vpos=%u\n",
>> - vbuf, vsize, vpos);
>> + "GCOV_KERNEL: something wrong in file %s: vbuf=%p vsize=%u"
>> + " vpos=%u\n",
>> + fp->info->filename, vbuf, vsize, vpos);
>> return 0;
>> }
>> len = vsize - vpos;
>> @@ -1207,8 +1235,9 @@ kernel_file_fwrite (const void *ptr, size_t size,
>>
>> if (len != nitems)
>> printk (KERN_ERR
>> - "GCOV_KERNEL: something wrong: size=%lu nitems=%lu ret=%d\n",
>> - size, nitems, len);
>> + "GCOV_KERNEL: something wrong in file %s: size=%lu nitems=%lu"
>> + " ret=%d, vsize=%u vpos=%u \n",
>> + fp->info->filename, size, nitems, len, vsize, vpos);
>> return len;
>> }
>>
>> Index: gcc/gcov-io.h
>> ===================================================================
>> --- gcc/gcov-io.h (revision 194562)
>> +++ gcc/gcov-io.h (working copy)
>> @@ -300,6 +300,14 @@ typedef unsigned gcov_type_unsigned __attribute__
>>
>> #endif /* BITS_PER_UNIT == 8 */
>>
>> +#if LONG_LONG_TYPE_SIZE > 32
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD_FN __sync_fetch_and_add_8
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD BUILT_IN_SYNC_FETCH_AND_ADD_8
>> +#else
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD_FN __sync_fetch_and_add_4
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD BUILT_IN_SYNC_FETCH_AND_ADD_4
>> +#endif
>> +
>> #undef EXTRACT_MODULE_ID_FROM_GLOBAL_ID
>> #undef EXTRACT_FUNC_ID_FROM_GLOBAL_ID
>> #undef GEN_FUNC_GLOBAL_ID
>> @@ -322,6 +330,18 @@ typedef unsigned gcov_type_unsigned __attribute__
>> typedef unsigned gcov_unsigned_t;
>> typedef unsigned gcov_position_t;
>>
>> +#if LONG_LONG_TYPE_SIZE > 32
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD_FN __sync_fetch_and_add_8
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD BUILT_IN_SYNC_FETCH_AND_ADD_8
>> +#else
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD_FN __sync_fetch_and_add_4
>> +#define GCOV_TYPE_SYNC_FETCH_AND_ADD BUILT_IN_SYNC_FETCH_AND_ADD_4
>> +#endif
>> +#define PROFILE_GEN_EDGE_ATOMIC (flag_profile_gen_atomic == 1 || \
>> + flag_profile_gen_atomic == 3)
>> +#define PROFILE_GEN_VALUE_ATOMIC (flag_profile_gen_atomic == 2 || \
>> + flag_profile_gen_atomic == 3)
>> +
>> /* gcov_type is typedef'd elsewhere for the compiler */
>> #if IN_GCOV
>> #define GCOV_LINKAGE static
>> @@ -781,8 +801,8 @@ struct gcov_info
>> unused) */
>>
>> unsigned n_functions; /* number of functions */
>> - const struct gcov_fn_info *const *functions; /* pointer to pointers
>> - to function information */
>> + const struct gcov_fn_info **functions; /* pointer to pointers
>> + to function information */
>> };
>>
>> /* Information about a single imported module. */
>> @@ -988,8 +1008,7 @@ static void gcov_rewrite (void);
>> GCOV_LINKAGE void gcov_seek (gcov_position_t /*position*/) ATTRIBUTE_HIDDEN;
>> GCOV_LINKAGE void gcov_truncate (void) ATTRIBUTE_HIDDEN;
>> GCOV_LINKAGE gcov_unsigned_t gcov_string_length (const char *)
>> ATTRIBUTE_HIDDEN;
>> -GCOV_LINKAGE unsigned gcov_gcda_file_size (struct gcov_info *,
>> - struct gcov_summary *);
>> +GCOV_LINKAGE unsigned gcov_gcda_file_size (struct gcov_info *);
>> #else
>> /* Available outside libgcov */
>> GCOV_LINKAGE void gcov_sync (gcov_position_t /*base*/,
>>
>> --
>> This patch is available for review at http://codereview.appspot.com/6968046
>
>
>
> --
> Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
