[PATCH] lib: acpica: fix semaphore counting by waiting for threads to complete

Colin Ian King colin.king at canonical.com
Fri Jul 20 16:02:30 UTC 2012


On 20/07/12 02:55, IvanHu wrote:
> On 07/19/2012 04:44 PM, Colin King wrote:
>> From: Colin Ian King <colin.king at canonical.com>
>>
>> When executing Notify() handlers ACPICA creates separate threads which
>> we need to wait to complete before we do any semaphore usage accounting.
>> This is because these threads can themselves use internal or AML
>> semaphores
>> which will be in an unknown state if we do the start doing semaphore
>> usage accounted before we wait for them to terminate.  This patch adds
>> in an array to keep track of threads created by AcpiOsExecute and also
>> a pthread join on these running threads before we start counting any
>> used semaphores.
>>
>> Note that we have to deprecate the ACPICA verison of AcpiOsExecute and
>> re-implement this in fwts to allow us to do the thread creation tracking.
>>
>> Signed-off-by: Colin Ian King <colin.king at canonical.com>
>> ---
>>   src/acpica/Makefile.am   |    3 +-
>>   src/acpica/fwts_acpica.c |  106
>> ++++++++++++++++++++++++++++++++++++++++++++++
>>   2 files changed, 108 insertions(+), 1 deletion(-)
>>
>> diff --git a/src/acpica/Makefile.am b/src/acpica/Makefile.am
>> index e2213d5..6b3bfa5 100644
>> --- a/src/acpica/Makefile.am
>> +++ b/src/acpica/Makefile.am
>> @@ -24,7 +24,8 @@ osunixxf_munged.c: $(ACPICA_OSL)/osunixxf.c
>>       sed 's/^AcpiOsDeleteSemaphore/__AcpiOsDeleteSemaphore/' | \
>>       sed 's/^AcpiOsVprintf/__AcpiOsVprintf/' | \
>>       sed 's/^AcpiOsSignal/__AcpiOsSignal/' | \
>> -    sed 's/^AcpiOsSleep/__AcpiOsSleep/' \
>> +    sed 's/^AcpiOsSleep/__AcpiOsSleep/' | \
>> +    sed 's/^AcpiOsExecute/__AcpiOsExecute/' \
>>       > osunixxf_munged.c
>>
>>   #
>> diff --git a/src/acpica/fwts_acpica.c b/src/acpica/fwts_acpica.c
>> index cf9a4fe..08b012d 100644
>> --- a/src/acpica/fwts_acpica.c
>> +++ b/src/acpica/fwts_acpica.c
>> @@ -32,6 +32,7 @@
>>   #include <pthread.h>
>>
>>   static pthread_mutex_t mutex_lock_count;
>> +static pthread_mutex_t mutex_thread_info;
>>
>>   #include "fwts.h"
>>
>> @@ -54,11 +55,15 @@ static pthread_mutex_t mutex_lock_count;
>>   #define MAX_SEMAPHORES        (1009)
>>   #define HASH_FULL        (0xffffffff)
>>
>> +#define MAX_THREADS        (128)
>> +
>>   typedef struct {
>>       sem_t        *sem;    /* Semaphore handle */
>>       int        count;    /* count > 0 if acquired */
>>   } sem_hash;
>>
>> +typedef void * (*PTHREAD_CALLBACK)(void *);
>> +
>>   BOOLEAN AcpiGbl_IgnoreErrors = FALSE;
>>   UINT8   AcpiGbl_RegionFillValue = 0;
>>
>> @@ -70,6 +75,16 @@ static sem_hash
>> sem_hash_table[MAX_SEMAPHORES];
>>   static ACPI_TABLE_DESC        Tables[ACPI_MAX_INIT_TABLES];
>>
>>   /*
>> + *  Used to account for threads used by AcpiOsExecute
>> + */
>> +typedef struct {
>> +    bool        used;    /* true if the thread accounting info in use
>> by a thread */
>> +    pthread_t    thread;    /* thread info */
>> +} fwts_thread;
>> +
>> +static fwts_thread    threads[MAX_THREADS];
>> +
>> +/*
>>    *  Static copies of ACPI tables used by ACPICA execution engine
>>    */
>>   static ACPI_TABLE_XSDT         *fwts_acpica_XSDT;
>> @@ -133,6 +148,27 @@ void fwts_acpica_sem_count_get(int *acquired, int
>> *released)
>>       *acquired = 0;
>>       *released = 0;
>>
>> +    /* Wait for any pending threads to complete */
>> +
>> +    for (i = 0; i < MAX_THREADS; i++) {
>> +        pthread_mutex_lock(&mutex_thread_info);
>> +        if (threads[i].used) {
>> +            pthread_mutex_unlock(&mutex_thread_info);
>> +
>> +            /* Wait for thread to complete */
>> +            pthread_join(threads[i].thread, NULL);
>> +
>> +            pthread_mutex_lock(&mutex_thread_info);
>> +            threads[i].used = false;
>> +            pthread_mutex_unlock(&mutex_thread_info);
>> +        }
>> +        pthread_mutex_unlock(&mutex_thread_info);
>> +    }
>> +
>> +    /*
>> +     * All threads (such as Notify() calls now complete, so
>> +     * we can now do the semaphore accounting calculations
>> +     */
>>       for (i=0;i<MAX_SEMAPHORES;i++) {
>>           if (sem_hash_table[i].sem != NULL) {
>>               (*acquired)++;
>> @@ -624,6 +660,74 @@ ACPI_STATUS AcpiOsReadPort(ACPI_IO_ADDRESS addr,
>> UINT32 *value, UINT32 width)
>>       return AE_OK;
>>   }
>>
>> +typedef struct {
>> +    PTHREAD_CALLBACK    func;
>> +    void *            context;
>> +    int            thread_index;
>> +} fwts_func_wrapper_context;
>> +
>> +/*
>> + *  fwts_pthread_func_wrapper()
>> + *    wrap the AcpiOsExecute function so we can mark the thread
>> + *    accounting free once the function has completed.
>> + */
>> +void *fwts_pthread_func_wrapper(fwts_func_wrapper_context *ctx)
>> +{
>> +    void *ret;
>> +
>> +    ret = ctx->func(ctx->context);
>> +
>> +    pthread_mutex_lock(&mutex_thread_info);
>> +    threads[ctx->thread_index].used = false;
>> +    pthread_mutex_unlock(&mutex_thread_info);
>> +
>> +    free(ctx);
>> +
>> +    return ret;
>> +}
>> +
>> +ACPI_STATUS AcpiOsExecute(
>> +    ACPI_EXECUTE_TYPE       type,
>> +    ACPI_OSD_EXEC_CALLBACK  function,
>> +    void                    *func_context)
>> +{
>> +    int    ret;
>> +    int     i;
>> +
>> +    pthread_mutex_lock(&mutex_thread_info);
>> +
>> +    /* Find a free slot to do per-thread join tracking */
>> +    for (i = 0; i < MAX_THREADS; i++) {
>> +        if (!threads[i].used) {
>> +            fwts_func_wrapper_context *ctx;
>> +
>> +            /* We need some context to pass through to the thread
>> wrapper */
>> +            if ((ctx = malloc(sizeof(fwts_func_wrapper_context))) ==
>> NULL) {
>> +                pthread_mutex_unlock(&mutex_thread_info);
>> +                return AE_NO_MEMORY;
>> +            }
>> +
>> +            ctx->func = (PTHREAD_CALLBACK)function;
>> +            ctx->context = func_context;
>> +            ctx->thread_index = i;
>> +            threads[i].used = true;
>> +
>> +            ret = pthread_create(&threads[i].thread, NULL,
>> +                (PTHREAD_CALLBACK)fwts_pthread_func_wrapper, ctx);
>> +            pthread_mutex_unlock(&mutex_thread_info);
>> +
>> +            if (ret)
>> +                return AE_ERROR;
>> +
>> +            return AE_OK;
>> +        }
>> +    }
>> +
>> +    /* No free slots, failed! */
>> +    pthread_mutex_unlock(&mutex_thread_info);
>> +    return AE_NO_MEMORY;
>> +}
>> +
>>   /*
>>    *  AcpiOsReadPciConfiguration()
>>    *    Override ACPICA AcpiOsReadPciConfiguration to fake PCI reads
>> @@ -802,6 +906,7 @@ int fwts_acpica_init(fwts_framework *fw)
>>           return FWTS_ERROR;
>>
>>       pthread_mutex_init(&mutex_lock_count, NULL);
>> +    pthread_mutex_init(&mutex_thread_info, NULL);
>>
>>       fwts_acpica_fw = fw;
>>
>> @@ -990,6 +1095,7 @@ int fwts_acpica_deinit(void)
>>
>>       AcpiTerminate();
>>       pthread_mutex_destroy(&mutex_lock_count);
>> +    pthread_mutex_destroy(&mutex_thread_info);
>>
>>       FWTS_ACPICA_FREE(fwts_acpica_XSDT);
>>       FWTS_ACPICA_FREE(fwts_acpica_RSDT);
>>
>
> it seems that multiple definition of `AcpiOsExecute' cause build error:
>
> .libs/osunixxf_munged.o: In function `AcpiOsExecute':
> /home/ivanhu/fwts/src/acpica/osunixxf_munged.c:1306: multiple definition
> of `AcpiOsExecute'
> .libs/fwts_acpica.o:/home/ivanhu/fwts/src/acpica/fwts_acpica.c:693:
> first defined here
> collect2: ld returned 1 exit status
> make[4]: *** [libfwtsacpica.la] Error 1
> make[4]: Leaving directory `/home/ivanhu/fwts/src/acpica'
> make[3]: *** [all] Error 2
> make[3]: Leaving directory `/home/ivanhu/fwts/src/acpica'
> make[2]: *** [all-recursive] Error 1
> make[2]: Leaving directory `/home/ivanhu/fwts/src'
> make[1]: *** [all-recursive] Error 1
> make[1]: Leaving directory `/home/ivanhu/fwts'
> make: *** [all] Error 2
>
>

The "munged" file osunixxf_munged.c hasn't been re-munged, so do a "make 
clean" and re-make, it should be OK after that.




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