Use the generic sysfs_emit_at() function take place of scnprintf()
Signed-off-by: Qi Liu <[email protected]>
---
drivers/perf/arm-ccn.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)
diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
index 3a2ddc0..0588f29 100644
--- a/drivers/perf/arm-ccn.c
+++ b/drivers/perf/arm-ccn.c
@@ -328,41 +328,37 @@ static ssize_t arm_ccn_pmu_event_show(struct device *dev,
struct arm_ccn_pmu_event, attr);
ssize_t res;
- res = scnprintf(buf, PAGE_SIZE, "type=0x%x", event->type);
+ res = sysfs_emit(buf, "type=0x%x", event->type);
if (event->event)
- res += scnprintf(buf + res, PAGE_SIZE - res, ",event=0x%x",
+ res += sysfs_emit_at(buf + res, res, ",event=0x%x",
event->event);
if (event->def)
- res += scnprintf(buf + res, PAGE_SIZE - res, ",%s",
- event->def);
+ res += sysfs_emit_at(buf + res, res, ",%s", event->def);
if (event->mask)
- res += scnprintf(buf + res, PAGE_SIZE - res, ",mask=0x%x",
- event->mask);
+ res += sysfs_emit_at(buf + res, res, ",mask=0x%x", event->mask);
/* Arguments required by an event */
switch (event->type) {
case CCN_TYPE_CYCLES:
break;
case CCN_TYPE_XP:
- res += scnprintf(buf + res, PAGE_SIZE - res,
- ",xp=?,vc=?");
+ res += sysfs_emit(buf + res, res, ",xp=?,vc=?");
if (event->event == CCN_EVENT_WATCHPOINT)
- res += scnprintf(buf + res, PAGE_SIZE - res,
+ res += sysfs_emit_at(buf + res, res,
",port=?,dir=?,cmp_l=?,cmp_h=?,mask=?");
else
- res += scnprintf(buf + res, PAGE_SIZE - res,
- ",bus=?");
+ res += sysfs_emit_at(buf + res, res, ",bus=?");
break;
case CCN_TYPE_MN:
- res += scnprintf(buf + res, PAGE_SIZE - res, ",node=%d", ccn->mn_id);
+ res += sysfs_emit_at(buf + res, res, ",node=%d", ccn->mn_id);
break;
default:
- res += scnprintf(buf + res, PAGE_SIZE - res, ",node=?");
+ res += sysfs_emit_at(buf + res, res, ",node=?");
break;
}
- res += scnprintf(buf + res, PAGE_SIZE - res, "\n");
+ res += sysfs_emit_at(buf + res, res, "\n");
return res;
}
--
2.8.1
Hi Qi,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v5.12-rc3 next-20210317]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Qi-Liu/drivers-perf-convert-sysfs-sprintf-snprintf-scnprintf-to-sysfs_emit/20210317-174750
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 1df27313f50a57497c1faeb6a6ae4ca939c85a7d
config: arm64-randconfig-s031-20210317 (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# apt-get install sparse
# sparse version: v0.6.3-277-gc089cd2d-dirty
# https://github.com/0day-ci/linux/commit/81a69a2f7fa73d0c41d699d6c6993c2594001241
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Qi-Liu/drivers-perf-convert-sysfs-sprintf-snprintf-scnprintf-to-sysfs_emit/20210317-174750
git checkout 81a69a2f7fa73d0c41d699d6c6993c2594001241
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
sparse warnings: (new ones prefixed by >>)
>> drivers/perf/arm-ccn.c:345:46: sparse: sparse: incorrect type in argument 2 (different base types) @@ expected char const *fmt @@ got long [assigned] [usertype] res @@
drivers/perf/arm-ccn.c:345:46: sparse: expected char const *fmt
drivers/perf/arm-ccn.c:345:46: sparse: got long [assigned] [usertype] res
vim +345 drivers/perf/arm-ccn.c
274
275 #define CCN_EVENT_ATTR(_name) \
276 __ATTR(_name, S_IRUGO, arm_ccn_pmu_event_show, NULL)
277
278 /*
279 * Events defined in TRM for MN, HN-I and SBSX are actually watchpoints set on
280 * their ports in XP they are connected to. For the sake of usability they are
281 * explicitly defined here (and translated into a relevant watchpoint in
282 * arm_ccn_pmu_event_init()) so the user can easily request them without deep
283 * knowledge of the flit format.
284 */
285
286 #define CCN_EVENT_MN(_name, _def, _mask) { .attr = CCN_EVENT_ATTR(mn_##_name), \
287 .type = CCN_TYPE_MN, .event = CCN_EVENT_WATCHPOINT, \
288 .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, \
289 .def = _def, .mask = _mask, }
290
291 #define CCN_EVENT_HNI(_name, _def, _mask) { \
292 .attr = CCN_EVENT_ATTR(hni_##_name), .type = CCN_TYPE_HNI, \
293 .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
294 .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
295
296 #define CCN_EVENT_SBSX(_name, _def, _mask) { \
297 .attr = CCN_EVENT_ATTR(sbsx_##_name), .type = CCN_TYPE_SBSX, \
298 .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
299 .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
300
301 #define CCN_EVENT_HNF(_name, _event) { .attr = CCN_EVENT_ATTR(hnf_##_name), \
302 .type = CCN_TYPE_HNF, .event = _event, }
303
304 #define CCN_EVENT_XP(_name, _event) { .attr = CCN_EVENT_ATTR(xp_##_name), \
305 .type = CCN_TYPE_XP, .event = _event, \
306 .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, }
307
308 /*
309 * RN-I & RN-D (RN-D = RN-I + DVM) nodes have different type ID depending
310 * on configuration. One of them is picked to represent the whole group,
311 * as they all share the same event types.
312 */
313 #define CCN_EVENT_RNI(_name, _event) { .attr = CCN_EVENT_ATTR(rni_##_name), \
314 .type = CCN_TYPE_RNI_3P, .event = _event, }
315
316 #define CCN_EVENT_SBAS(_name, _event) { .attr = CCN_EVENT_ATTR(sbas_##_name), \
317 .type = CCN_TYPE_SBAS, .event = _event, }
318
319 #define CCN_EVENT_CYCLES(_name) { .attr = CCN_EVENT_ATTR(_name), \
320 .type = CCN_TYPE_CYCLES }
321
322
323 static ssize_t arm_ccn_pmu_event_show(struct device *dev,
324 struct device_attribute *attr, char *buf)
325 {
326 struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev));
327 struct arm_ccn_pmu_event *event = container_of(attr,
328 struct arm_ccn_pmu_event, attr);
329 ssize_t res;
330
331 res = sysfs_emit(buf, "type=0x%x", event->type);
332 if (event->event)
333 res += sysfs_emit_at(buf + res, res, ",event=0x%x",
334 event->event);
335 if (event->def)
336 res += sysfs_emit_at(buf + res, res, ",%s", event->def);
337 if (event->mask)
338 res += sysfs_emit_at(buf + res, res, ",mask=0x%x", event->mask);
339
340 /* Arguments required by an event */
341 switch (event->type) {
342 case CCN_TYPE_CYCLES:
343 break;
344 case CCN_TYPE_XP:
> 345 res += sysfs_emit(buf + res, res, ",xp=?,vc=?");
346 if (event->event == CCN_EVENT_WATCHPOINT)
347 res += sysfs_emit_at(buf + res, res,
348 ",port=?,dir=?,cmp_l=?,cmp_h=?,mask=?");
349 else
350 res += sysfs_emit_at(buf + res, res, ",bus=?");
351
352 break;
353 case CCN_TYPE_MN:
354 res += sysfs_emit_at(buf + res, res, ",node=%d", ccn->mn_id);
355 break;
356 default:
357 res += sysfs_emit_at(buf + res, res, ",node=?");
358 break;
359 }
360
361 res += sysfs_emit_at(buf + res, res, "\n");
362
363 return res;
364 }
365
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
Hi Qi,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v5.12-rc3 next-20210317]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Qi-Liu/drivers-perf-convert-sysfs-sprintf-snprintf-scnprintf-to-sysfs_emit/20210317-174750
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 1df27313f50a57497c1faeb6a6ae4ca939c85a7d
config: arm-randconfig-r036-20210317 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 8ef111222a3dd12a9175f69c3bff598c46e8bdf7)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm cross compiling tool for clang build
# apt-get install binutils-arm-linux-gnueabi
# https://github.com/0day-ci/linux/commit/81a69a2f7fa73d0c41d699d6c6993c2594001241
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Qi-Liu/drivers-perf-convert-sysfs-sprintf-snprintf-scnprintf-to-sysfs_emit/20210317-174750
git checkout 81a69a2f7fa73d0c41d699d6c6993c2594001241
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
>> drivers/perf/arm-ccn.c:345:32: warning: incompatible integer to pointer conversion passing 'ssize_t' (aka 'int') to parameter of type 'const char *' [-Wint-conversion]
res += sysfs_emit(buf + res, res, ",xp=?,vc=?");
^~~
include/linux/sysfs.h:335:39: note: passing argument to parameter 'fmt' here
int sysfs_emit(char *buf, const char *fmt, ...);
^
1 warning generated.
vim +345 drivers/perf/arm-ccn.c
274
275 #define CCN_EVENT_ATTR(_name) \
276 __ATTR(_name, S_IRUGO, arm_ccn_pmu_event_show, NULL)
277
278 /*
279 * Events defined in TRM for MN, HN-I and SBSX are actually watchpoints set on
280 * their ports in XP they are connected to. For the sake of usability they are
281 * explicitly defined here (and translated into a relevant watchpoint in
282 * arm_ccn_pmu_event_init()) so the user can easily request them without deep
283 * knowledge of the flit format.
284 */
285
286 #define CCN_EVENT_MN(_name, _def, _mask) { .attr = CCN_EVENT_ATTR(mn_##_name), \
287 .type = CCN_TYPE_MN, .event = CCN_EVENT_WATCHPOINT, \
288 .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, \
289 .def = _def, .mask = _mask, }
290
291 #define CCN_EVENT_HNI(_name, _def, _mask) { \
292 .attr = CCN_EVENT_ATTR(hni_##_name), .type = CCN_TYPE_HNI, \
293 .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
294 .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
295
296 #define CCN_EVENT_SBSX(_name, _def, _mask) { \
297 .attr = CCN_EVENT_ATTR(sbsx_##_name), .type = CCN_TYPE_SBSX, \
298 .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
299 .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
300
301 #define CCN_EVENT_HNF(_name, _event) { .attr = CCN_EVENT_ATTR(hnf_##_name), \
302 .type = CCN_TYPE_HNF, .event = _event, }
303
304 #define CCN_EVENT_XP(_name, _event) { .attr = CCN_EVENT_ATTR(xp_##_name), \
305 .type = CCN_TYPE_XP, .event = _event, \
306 .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, }
307
308 /*
309 * RN-I & RN-D (RN-D = RN-I + DVM) nodes have different type ID depending
310 * on configuration. One of them is picked to represent the whole group,
311 * as they all share the same event types.
312 */
313 #define CCN_EVENT_RNI(_name, _event) { .attr = CCN_EVENT_ATTR(rni_##_name), \
314 .type = CCN_TYPE_RNI_3P, .event = _event, }
315
316 #define CCN_EVENT_SBAS(_name, _event) { .attr = CCN_EVENT_ATTR(sbas_##_name), \
317 .type = CCN_TYPE_SBAS, .event = _event, }
318
319 #define CCN_EVENT_CYCLES(_name) { .attr = CCN_EVENT_ATTR(_name), \
320 .type = CCN_TYPE_CYCLES }
321
322
323 static ssize_t arm_ccn_pmu_event_show(struct device *dev,
324 struct device_attribute *attr, char *buf)
325 {
326 struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev));
327 struct arm_ccn_pmu_event *event = container_of(attr,
328 struct arm_ccn_pmu_event, attr);
329 ssize_t res;
330
331 res = sysfs_emit(buf, "type=0x%x", event->type);
332 if (event->event)
333 res += sysfs_emit_at(buf + res, res, ",event=0x%x",
334 event->event);
335 if (event->def)
336 res += sysfs_emit_at(buf + res, res, ",%s", event->def);
337 if (event->mask)
338 res += sysfs_emit_at(buf + res, res, ",mask=0x%x", event->mask);
339
340 /* Arguments required by an event */
341 switch (event->type) {
342 case CCN_TYPE_CYCLES:
343 break;
344 case CCN_TYPE_XP:
> 345 res += sysfs_emit(buf + res, res, ",xp=?,vc=?");
346 if (event->event == CCN_EVENT_WATCHPOINT)
347 res += sysfs_emit_at(buf + res, res,
348 ",port=?,dir=?,cmp_l=?,cmp_h=?,mask=?");
349 else
350 res += sysfs_emit_at(buf + res, res, ",bus=?");
351
352 break;
353 case CCN_TYPE_MN:
354 res += sysfs_emit_at(buf + res, res, ",node=%d", ccn->mn_id);
355 break;
356 default:
357 res += sysfs_emit_at(buf + res, res, ",node=?");
358 break;
359 }
360
361 res += sysfs_emit_at(buf + res, res, "\n");
362
363 return res;
364 }
365
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
Hi Qi,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on linus/master]
[also build test WARNING on v5.12-rc3 next-20210317]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Qi-Liu/drivers-perf-convert-sysfs-sprintf-snprintf-scnprintf-to-sysfs_emit/20210317-174750
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 1df27313f50a57497c1faeb6a6ae4ca939c85a7d
config: arm64-randconfig-r003-20210317 (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/81a69a2f7fa73d0c41d699d6c6993c2594001241
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Qi-Liu/drivers-perf-convert-sysfs-sprintf-snprintf-scnprintf-to-sysfs_emit/20210317-174750
git checkout 81a69a2f7fa73d0c41d699d6c6993c2594001241
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
All warnings (new ones prefixed by >>):
drivers/perf/arm-ccn.c: In function 'arm_ccn_pmu_event_show':
>> drivers/perf/arm-ccn.c:345:32: warning: passing argument 2 of 'sysfs_emit' makes pointer from integer without a cast [-Wint-conversion]
345 | res += sysfs_emit(buf + res, res, ",xp=?,vc=?");
| ^~~
| |
| ssize_t {aka long int}
In file included from include/linux/kobject.h:20,
from include/linux/irqdesc.h:6,
from include/linux/irq.h:584,
from include/asm-generic/hardirq.h:17,
from arch/arm64/include/asm/hardirq.h:17,
from include/linux/hardirq.h:10,
from include/linux/interrupt.h:11,
from drivers/perf/arm-ccn.c:10:
include/linux/sysfs.h:335:39: note: expected 'const char *' but argument is of type 'ssize_t' {aka 'long int'}
335 | int sysfs_emit(char *buf, const char *fmt, ...);
| ~~~~~~~~~~~~^~~
vim +/sysfs_emit +345 drivers/perf/arm-ccn.c
274
275 #define CCN_EVENT_ATTR(_name) \
276 __ATTR(_name, S_IRUGO, arm_ccn_pmu_event_show, NULL)
277
278 /*
279 * Events defined in TRM for MN, HN-I and SBSX are actually watchpoints set on
280 * their ports in XP they are connected to. For the sake of usability they are
281 * explicitly defined here (and translated into a relevant watchpoint in
282 * arm_ccn_pmu_event_init()) so the user can easily request them without deep
283 * knowledge of the flit format.
284 */
285
286 #define CCN_EVENT_MN(_name, _def, _mask) { .attr = CCN_EVENT_ATTR(mn_##_name), \
287 .type = CCN_TYPE_MN, .event = CCN_EVENT_WATCHPOINT, \
288 .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, \
289 .def = _def, .mask = _mask, }
290
291 #define CCN_EVENT_HNI(_name, _def, _mask) { \
292 .attr = CCN_EVENT_ATTR(hni_##_name), .type = CCN_TYPE_HNI, \
293 .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
294 .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
295
296 #define CCN_EVENT_SBSX(_name, _def, _mask) { \
297 .attr = CCN_EVENT_ATTR(sbsx_##_name), .type = CCN_TYPE_SBSX, \
298 .event = CCN_EVENT_WATCHPOINT, .num_ports = CCN_NUM_XP_PORTS, \
299 .num_vcs = CCN_NUM_VCS, .def = _def, .mask = _mask, }
300
301 #define CCN_EVENT_HNF(_name, _event) { .attr = CCN_EVENT_ATTR(hnf_##_name), \
302 .type = CCN_TYPE_HNF, .event = _event, }
303
304 #define CCN_EVENT_XP(_name, _event) { .attr = CCN_EVENT_ATTR(xp_##_name), \
305 .type = CCN_TYPE_XP, .event = _event, \
306 .num_ports = CCN_NUM_XP_PORTS, .num_vcs = CCN_NUM_VCS, }
307
308 /*
309 * RN-I & RN-D (RN-D = RN-I + DVM) nodes have different type ID depending
310 * on configuration. One of them is picked to represent the whole group,
311 * as they all share the same event types.
312 */
313 #define CCN_EVENT_RNI(_name, _event) { .attr = CCN_EVENT_ATTR(rni_##_name), \
314 .type = CCN_TYPE_RNI_3P, .event = _event, }
315
316 #define CCN_EVENT_SBAS(_name, _event) { .attr = CCN_EVENT_ATTR(sbas_##_name), \
317 .type = CCN_TYPE_SBAS, .event = _event, }
318
319 #define CCN_EVENT_CYCLES(_name) { .attr = CCN_EVENT_ATTR(_name), \
320 .type = CCN_TYPE_CYCLES }
321
322
323 static ssize_t arm_ccn_pmu_event_show(struct device *dev,
324 struct device_attribute *attr, char *buf)
325 {
326 struct arm_ccn *ccn = pmu_to_arm_ccn(dev_get_drvdata(dev));
327 struct arm_ccn_pmu_event *event = container_of(attr,
328 struct arm_ccn_pmu_event, attr);
329 ssize_t res;
330
331 res = sysfs_emit(buf, "type=0x%x", event->type);
332 if (event->event)
333 res += sysfs_emit_at(buf + res, res, ",event=0x%x",
334 event->event);
335 if (event->def)
336 res += sysfs_emit_at(buf + res, res, ",%s", event->def);
337 if (event->mask)
338 res += sysfs_emit_at(buf + res, res, ",mask=0x%x", event->mask);
339
340 /* Arguments required by an event */
341 switch (event->type) {
342 case CCN_TYPE_CYCLES:
343 break;
344 case CCN_TYPE_XP:
> 345 res += sysfs_emit(buf + res, res, ",xp=?,vc=?");
346 if (event->event == CCN_EVENT_WATCHPOINT)
347 res += sysfs_emit_at(buf + res, res,
348 ",port=?,dir=?,cmp_l=?,cmp_h=?,mask=?");
349 else
350 res += sysfs_emit_at(buf + res, res, ",bus=?");
351
352 break;
353 case CCN_TYPE_MN:
354 res += sysfs_emit_at(buf + res, res, ",node=%d", ccn->mn_id);
355 break;
356 default:
357 res += sysfs_emit_at(buf + res, res, ",node=?");
358 break;
359 }
360
361 res += sysfs_emit_at(buf + res, res, "\n");
362
363 return res;
364 }
365
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]
On Wed, 2021-03-17 at 17:41 +0800, Qi Liu wrote:
> Use the generic sysfs_emit_at() function take place of scnprintf()
[]
> diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
[]
> @@ -328,41 +328,37 @@ static ssize_t arm_ccn_pmu_event_show(struct device *dev,
> ? struct arm_ccn_pmu_event, attr);
> ? ssize_t res;
> ?
>
> - res = scnprintf(buf, PAGE_SIZE, "type=0x%x", event->type);
> + res = sysfs_emit(buf, "type=0x%x", event->type);
> ? if (event->event)
> - res += scnprintf(buf + res, PAGE_SIZE - res, ",event=0x%x",
> + res += sysfs_emit_at(buf + res, res, ",event=0x%x",
> ? event->event);
sysfs_emit_at should always use buf, not buf + offset.
res should be int and is the offset from buf for the output
so the form should be similar to
int len;
len = sysfs_emit(buf, "type=0x%x", event->type);
if (event->event) {
len += sysfs_emit_at(buf, len, ",event=0x%x", event->event);
etc...
On 2021/3/17 22:57, Joe Perches wrote:
> On Wed, 2021-03-17 at 17:41 +0800, Qi Liu wrote:
>> Use the generic sysfs_emit_at() function take place of scnprintf()
> []
>> diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
> []
>> @@ -328,41 +328,37 @@ static ssize_t arm_ccn_pmu_event_show(struct device *dev,
>> struct arm_ccn_pmu_event, attr);
>> ssize_t res;
>>
>>
>> - res = scnprintf(buf, PAGE_SIZE, "type=0x%x", event->type);
>> + res = sysfs_emit(buf, "type=0x%x", event->type);
>> if (event->event)
>> - res += scnprintf(buf + res, PAGE_SIZE - res, ",event=0x%x",
>> + res += sysfs_emit_at(buf + res, res, ",event=0x%x",
>> event->event);
>
> sysfs_emit_at should always use buf, not buf + offset.
> res should be int and is the offset from buf for the output
>
> so the form should be similar to
>
> int len;
>
> len = sysfs_emit(buf, "type=0x%x", event->type);
> if (event->event) {
> len += sysfs_emit_at(buf, len, ",event=0x%x", event->event);
>
> etc...
>
Hi Joe,
I'll fix the use of sysfs_emit_at in next version, thanks.
But I think it's better to keep the res as ssize_t, as the return value
of this function is ssize_t.
Thanks,
Qi
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>
On Thu, 2021-03-18 at 17:33 +0800, liuqi (BA) wrote:
> On 2021/3/17 22:57, Joe Perches wrote:
> > On Wed, 2021-03-17 at 17:41 +0800, Qi Liu wrote:
> > > Use the generic sysfs_emit_at() function take place of scnprintf()
> > []
> > > diff --git a/drivers/perf/arm-ccn.c b/drivers/perf/arm-ccn.c
> > []
> > > @@ -328,41 +328,37 @@ static ssize_t arm_ccn_pmu_event_show(struct device *dev,
> > > struct arm_ccn_pmu_event, attr);
> > > ssize_t res;
> > >
> > >
> > >
> > > - res = scnprintf(buf, PAGE_SIZE, "type=0x%x", event->type);
> > > + res = sysfs_emit(buf, "type=0x%x", event->type);
> > > if (event->event)
> > > - res += scnprintf(buf + res, PAGE_SIZE - res, ",event=0x%x",
> > > + res += sysfs_emit_at(buf + res, res, ",event=0x%x",
> > > event->event);
> >
> > sysfs_emit_at should always use buf, not buf + offset.
> > res should be int and is the offset from buf for the output
> >
> > so the form should be similar to
> >
> > int len;
> >
> > len = sysfs_emit(buf, "type=0x%x", event->type);
> > if (event->event) {
> > len += sysfs_emit_at(buf, len, ",event=0x%x", event->event);
> >
> > etc...
> >
> Hi Joe,
>
> I'll fix the use of sysfs_emit_at in next version, thanks.
> But I think it's better to keep the res as ssize_t, as the return value
> of this function is ssize_t.
The 2nd arg of sysfs_emit_at is int.
On 64 bit platforms, ssize_t is 64 bit while int is 32.
If res (or len) is ssize_t, there could be a lot of -Wconversion warnings
like this produced when using make W=
warning: conversion from ‘ssize_t’ {aka ‘long int’} to ‘int’ may change value [-Wconversion]
262 | len += sysfs_emit_at(buf, len, "\n");