From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <5821A331.5060405@codeaurora.org> Date: Tue, 08 Nov 2016 15:34:33 +0530 From: Rajendra Nayak MIME-Version: 1.0 To: Geert Uytterhoeven CC: Stephen Boyd , Michael Turquette , linux-clk , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] clk: Free struct clk allocated during clk_hw_register() References: <1478593430-23102-1-git-send-email-rnayak@codeaurora.org> In-Reply-To: Content-Type: text/plain; charset=utf-8 List-ID: On 11/08/2016 03:06 PM, Geert Uytterhoeven wrote: > Hi Rajendra, > > On Tue, Nov 8, 2016 at 9:23 AM, Rajendra Nayak wrote: >> With clk_hw_register() API we hide the struct clk from the caller >> and return an int error code instead, so the caller (clk provider) >> is not expected to use hw->clk on return. > > That's correct, in case of failure. sorry, maybe the commit text needs to be reworded. I meant 'clk_hw_register() returns an int (not a struct clk pointer), 0 on success or an error code in case of a failure. > >> Free the memory, and mark hw->clk as NULL before returning. >> >> Signed-off-by: Rajendra Nayak >> --- >> drivers/clk/clk.c | 10 +++++++++- >> 1 file changed, 9 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c >> index 0fb39fe..f81e4aa 100644 >> --- a/drivers/clk/clk.c >> +++ b/drivers/clk/clk.c >> @@ -2628,7 +2628,15 @@ struct clk *clk_register(struct device *dev, struct clk_hw *hw) >> */ >> int clk_hw_register(struct device *dev, struct clk_hw *hw) >> { >> - return PTR_ERR_OR_ZERO(clk_register(dev, hw)); >> + struct clk *c; >> + >> + c = clk_register(dev, hw); >> + if (IS_ERR(c)) >> + return PTR_ERR(c); >> + >> + __clk_free_clk(c); >> + hw->clk = NULL; > > This is the success path, not the failure path (on failure, clk_register() > has already freed the struct clk). > Why do you free the struct clk in case of success? > > What am I missing? so with 'per-user' clks, I thought we now have one struct clk per user, allocated when the user does a clk_get() and freed with a clk_put(), so we shouldn't ideally need one during clk registration? The one allocated in clk_register() is for legacy users who need to get a struct clk * back. For users of clk_hw_register() this should not be needed, no? > >> + return 0; >> } >> EXPORT_SYMBOL_GPL(clk_hw_register); > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation