pt., 30 sie 2019 o 10:15 Thierry Reding <thierry.reding@xxxxxxxxx> napisał(a): > > On Fri, Aug 30, 2019 at 09:17:36AM +0200, Bartosz Golaszewski wrote: > > From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> > > > > There are ~80 users of regulator bulk APIs that set the supply names > > in a for loop before using the bulk helpers. > > > > This series proposes to add a helper function for setting supply names > > and uses it in a couple tegra drivers. If accepted: a coccinelle script > > should be easy to develop that would address this in other drivers. > > > > Bartosz Golaszewski (4): > > regulator: provide regulator_bulk_set_supply_names() > > ahci: tegra: use regulator_bulk_set_supply_names() > > phy: tegra: use regulator_bulk_set_supply_names() > > usb: host: xhci-tegra: use regulator_bulk_set_supply_names() > > > > drivers/ata/ahci_tegra.c | 6 +++--- > > drivers/phy/tegra/xusb.c | 6 +++--- > > drivers/regulator/helpers.c | 21 +++++++++++++++++++++ > > drivers/usb/host/xhci-tegra.c | 5 +++-- > > include/linux/regulator/consumer.h | 12 ++++++++++++ > > 5 files changed, 42 insertions(+), 8 deletions(-) > > The diffstat here suggests that this isn't really helpful. Even if you > subtract the regulator code that adds the new helper, you actually have > a zero diffstat (and a positive one in one case). > You are right when it comes to LoC stats, but bloat-o-meter says it's quite useful when it comes to actual code size. This is what we're adding: $ ./scripts/bloat-o-meter drivers/regulator/helpers.o.old drivers/regulator/helpers.o add/remove: 3/0 grow/shrink: 0/0 up/down: 72/0 (72) Function old new delta regulator_bulk_set_supply_names - 32 +32 __kstrtab_regulator_bulk_set_supply_names - 32 +32 __ksymtab_regulator_bulk_set_supply_names - 8 +8 Total: Before=4438, After=4510, chg +1.62% And this is what we're removing just from one driver: $ ./scripts/bloat-o-meter ./drivers/ata/ahci_tegra.o.old ./drivers/ata/ahci_tegra.o add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-52 (-52) Function old new delta tegra_ahci_probe 1688 1636 -52 Total: Before=3474, After=3422, chg -1.50% > Instead, why don't we take this one step further and roll a bit more of > the boilerplate into the new helper, something along these lines: > > struct regulator_bulk_data * > devm_regulator_bulk_get_from_names(struct device *dev, > const char * const *supply_names, > unsigned int num_supplies) > { > struct regulator_bulk_data *data; > unsigned int i; > int err; > > data = devm_kcalloc(dev, num_supplies, sizeof(*data)); > if (!data) > return ERR_PTR(-ENOMEM); > > for (i = 0; i < num_supplies; i++) > data[i].supply = supply_names[i]; > > err = devm_regulator_bulk_get(dev, num_supplies, data); > if (err < 0) > return ERR_PTR(err); > > return data; > } > > That seems to be still a very common pattern and gets rid of a lot more > boilerplate, so your diffstat will actually start to be negative at some > point. > This looks like a good candidate for the next step, but I'd say this change is still worth applying. Bart > I suppose one could add a non-managed variant for this as well, but I'm > counting 6 uses of regulator_bulk_get() vs. ~140 uses of the managed > variant, so I'm not sure it's worth it. > > Thierry