| Message ID | 1560534863-15115-4-git-send-email-suzuki.poulose@arm.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | None | expand |
On Fri, Jun 14, 2019 at 7:54 PM Suzuki K Poulose <suzuki.poulose@arm.com> wrote: > > The prototype of bus_find_device() will be unified with that of > class_find_device() subsequently, but for this purpose the callback > functions passed to it need to take (const void *) as the second > argument. Consequently, they cannot modify the memory pointed to by > that argument which currently is not the case for acpi_dev_match_cb(). > However, acpi_dev_match_cb() really need not modify the "match" object > passed to it, because acpi_dev_get_first_match_dev() which uses it via > bus_find_device() can easily convert the result of bus_find_device() > into the pointer to return. > > For this reason, update acpi_dev_match_cb() to avoid the redundant > memory updates. > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > Cc: Len Brown <lenb@kernel.org> > Cc: linux-acpi@vger.kernel.org > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Or if you want me to take this patch, please let me know. > --- > drivers/acpi/utils.c | 7 +------ > 1 file changed, 1 insertion(+), 6 deletions(-) > > diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c > index 7def63a..1391b63 100644 > --- a/drivers/acpi/utils.c > +++ b/drivers/acpi/utils.c > @@ -725,8 +725,6 @@ bool acpi_dev_found(const char *hid) > EXPORT_SYMBOL(acpi_dev_found); > > struct acpi_dev_match_info { > - const char *dev_name; > - struct acpi_device *adev; > struct acpi_device_id hid[2]; > const char *uid; > s64 hrv; > @@ -746,9 +744,6 @@ static int acpi_dev_match_cb(struct device *dev, void *data) > strcmp(adev->pnp.unique_id, match->uid))) > return 0; > > - match->dev_name = acpi_dev_name(adev); > - match->adev = adev; > - > if (match->hrv == -1) > return 1; > > @@ -818,7 +813,7 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv) > match.hrv = hrv; > > dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb); > - return dev ? match.adev : NULL; > + return dev ? to_acpi_device(dev) : NULL; > } > EXPORT_SYMBOL(acpi_dev_get_first_match_dev); > > -- > 2.7.4 >
On Tue, Jun 18, 2019 at 12:08:45AM +0200, Rafael J. Wysocki wrote: > On Fri, Jun 14, 2019 at 7:54 PM Suzuki K Poulose <suzuki.poulose@arm.com> wrote: > > > > The prototype of bus_find_device() will be unified with that of > > class_find_device() subsequently, but for this purpose the callback > > functions passed to it need to take (const void *) as the second > > argument. Consequently, they cannot modify the memory pointed to by > > that argument which currently is not the case for acpi_dev_match_cb(). > > However, acpi_dev_match_cb() really need not modify the "match" object > > passed to it, because acpi_dev_get_first_match_dev() which uses it via > > bus_find_device() can easily convert the result of bus_find_device() > > into the pointer to return. > > > > For this reason, update acpi_dev_match_cb() to avoid the redundant > > memory updates. > > > > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > > Cc: Len Brown <lenb@kernel.org> > > Cc: linux-acpi@vger.kernel.org > > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > > Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > Or if you want me to take this patch, please let me know. I'll take it now, thanks. greg k-h
diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c index 7def63a..1391b63 100644 --- a/drivers/acpi/utils.c +++ b/drivers/acpi/utils.c @@ -725,8 +725,6 @@ bool acpi_dev_found(const char *hid) EXPORT_SYMBOL(acpi_dev_found); struct acpi_dev_match_info { - const char *dev_name; - struct acpi_device *adev; struct acpi_device_id hid[2]; const char *uid; s64 hrv; @@ -746,9 +744,6 @@ static int acpi_dev_match_cb(struct device *dev, void *data) strcmp(adev->pnp.unique_id, match->uid))) return 0; - match->dev_name = acpi_dev_name(adev); - match->adev = adev; - if (match->hrv == -1) return 1; @@ -818,7 +813,7 @@ acpi_dev_get_first_match_dev(const char *hid, const char *uid, s64 hrv) match.hrv = hrv; dev = bus_find_device(&acpi_bus_type, NULL, &match, acpi_dev_match_cb); - return dev ? match.adev : NULL; + return dev ? to_acpi_device(dev) : NULL; } EXPORT_SYMBOL(acpi_dev_get_first_match_dev);
The prototype of bus_find_device() will be unified with that of class_find_device() subsequently, but for this purpose the callback functions passed to it need to take (const void *) as the second argument. Consequently, they cannot modify the memory pointed to by that argument which currently is not the case for acpi_dev_match_cb(). However, acpi_dev_match_cb() really need not modify the "match" object passed to it, because acpi_dev_get_first_match_dev() which uses it via bus_find_device() can easily convert the result of bus_find_device() into the pointer to return. For this reason, update acpi_dev_match_cb() to avoid the redundant memory updates. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Len Brown <lenb@kernel.org> Cc: linux-acpi@vger.kernel.org Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> --- drivers/acpi/utils.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-)