diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2017-08-02 10:52:07 +1000 |
|---|---|---|
| committer | Stephen Rothwell <sfr@canb.auug.org.au> | 2017-08-07 16:03:16 +1000 |
| commit | 2a154141b480687ac9c8e32427eec5ba48c520ed (patch) | |
| tree | 36402604c3bade3742185aa32d7e52f368a7bddf | |
| parent | d30994ec6cd4006a7124f5b517d6ec0f6945dc58 (diff) | |
iopoll: avoid -Wint-in-bool-context warning
When we pass the result of a multiplication as the timeout or the delay,
we can get a warning from gcc-7:
drivers/mmc/host/bcm2835.c:596:149: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context]
drivers/mfd/arizona-core.c:247:195: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context]
drivers/gpu/drm/sun4i/sun4i_hdmi_i2c.c:49:27: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context]
The warning is a bit questionable inside of a macro, but this is
intentional on the side of the gcc developers. It is also an indication
of another problem: we evaluate the timeout and sleep arguments multiple
times, which can have undesired side-effects when those are complex
expressions.
This changes the three iopoll variants to use local variables for storing
copies of the timeouts. This adds some more type safety, and avoids both
the double-evaluation and the gcc warning.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81484
Link: http://lkml.kernel.org/r/20170726133756.2161367-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mark Brown <broonie@kernel.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Michael Grzeschik <m.grzeschik@pengutronix.de>
Cc: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Cc: "Alex A. Mihaylov" <minimumlaw@rambler.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
| -rw-r--r-- | include/linux/iopoll.h | 24 | ||||
| -rw-r--r-- | include/linux/regmap.h | 12 |
2 files changed, 22 insertions, 14 deletions
diff --git a/include/linux/iopoll.h b/include/linux/iopoll.h index d29e1e21bf3f..b1d861caca16 100644 --- a/include/linux/iopoll.h +++ b/include/linux/iopoll.h @@ -42,18 +42,21 @@ */ #define readx_poll_timeout(op, addr, val, cond, sleep_us, timeout_us) \ ({ \ - ktime_t timeout = ktime_add_us(ktime_get(), timeout_us); \ - might_sleep_if(sleep_us); \ + u64 __timeout_us = (timeout_us); \ + unsigned long __sleep_us = (sleep_us); \ + ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \ + might_sleep_if((__sleep_us) != 0); \ for (;;) { \ (val) = op(addr); \ if (cond) \ break; \ - if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \ + if (__timeout_us && \ + ktime_compare(ktime_get(), __timeout) > 0) { \ (val) = op(addr); \ break; \ } \ - if (sleep_us) \ - usleep_range((sleep_us >> 2) + 1, sleep_us); \ + if (__sleep_us) \ + usleep_range((__sleep_us >> 2) + 1, __sleep_us); \ } \ (cond) ? 0 : -ETIMEDOUT; \ }) @@ -77,17 +80,20 @@ */ #define readx_poll_timeout_atomic(op, addr, val, cond, delay_us, timeout_us) \ ({ \ - ktime_t timeout = ktime_add_us(ktime_get(), timeout_us); \ + u64 __timeout_us = (timeout_us); \ + unsigned long __delay_us = (delay_us); \ + ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \ for (;;) { \ (val) = op(addr); \ if (cond) \ break; \ - if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) { \ + if (__timeout_us && \ + ktime_compare(ktime_get(), __timeout) > 0) { \ (val) = op(addr); \ break; \ } \ - if (delay_us) \ - udelay(delay_us); \ + if (__delay_us) \ + udelay(__delay_us); \ } \ (cond) ? 0 : -ETIMEDOUT; \ }) diff --git a/include/linux/regmap.h b/include/linux/regmap.h index 1474ab0a3922..a4d30c877f6b 100644 --- a/include/linux/regmap.h +++ b/include/linux/regmap.h @@ -120,22 +120,24 @@ struct reg_sequence { */ #define regmap_read_poll_timeout(map, addr, val, cond, sleep_us, timeout_us) \ ({ \ - ktime_t __timeout = ktime_add_us(ktime_get(), timeout_us); \ + u64 __timeout_us = (timeout_us); \ + unsigned long __sleep_us = (sleep_us); \ + ktime_t __timeout = ktime_add_us(ktime_get(), __timeout_us); \ int __ret; \ - might_sleep_if(sleep_us); \ + might_sleep_if(__sleep_us); \ for (;;) { \ __ret = regmap_read((map), (addr), &(val)); \ if (__ret) \ break; \ if (cond) \ break; \ - if ((timeout_us) && \ + if (__timeout_us && \ ktime_compare(ktime_get(), __timeout) > 0) { \ __ret = regmap_read((map), (addr), &(val)); \ break; \ } \ - if (sleep_us) \ - usleep_range(((sleep_us) >> 2) + 1, sleep_us); \ + if (__sleep_us) \ + usleep_range((__sleep_us >> 2) + 1, __sleep_us); \ } \ __ret ?: ((cond) ? 0 : -ETIMEDOUT); \ }) |