move sleep_millisec to git-compat-util.h

From: Han-Wen Nienhuys <[email protected]>

The sleep function is defined in wrapper.c, so it makes more sense to be a in system compatibility header.

Signed-off-by Han-Wen Nienhuys <[email protected]>

---
move sleep_millisec to git-compat-util.h

To: Han-Wen Nienhuys via GitGitGadget <[email protected]>
Cc: [email protected]; Han-Wen Nienhuys <[email protected]>; Han- Wen Nienhuys <[email protected]>
Subject: Re: [PATCH] move sleep_millisec to git-compat-util.h

Quoted 2 lines · Han-Wen Nienhuys via GitGitGadget

From: Han-Wen Nienhuys <[email protected]>

Quoted 6 lines

The sleep function is defined in wrapper.c, so it makes more sense to be a in system compatibility header.

Signed-off-by Han-Wen Nienhuys <[email protected]>

---
move sleep_millisec to git-compat-util.h

Makes sense.

I have a platform fix that I'd like to apply once this makes it into the main code. The sleep_millisec uses poll(), which is rather heavy-weight on the NonStop platform. We have a much more efficient sleep function available (with microsecond resolution), which would be more useful unless there is a poll side-effect on which git depends. Would this be acceptable? I could push this at any time really.

index bcda41e374..972ecd67bf 100644

wrapper.c +8 -0

@@ -4,6 +4,10 @@
 #include "cache.h"
 #include "config.h"
 
+#ifdef __TANDEM
+#include <cextdecs> /* for PROCESS_DELAY_ */
+#endif
+
 static int memory_limit_check(size_t size, int gentle)
 {
        static size_t limit = 0;

@@ -650,7 +654,11 @@ void write_file(const char *path, const char *fmt, ...)
 
 void sleep_millisec(int millisec)
 {
+#ifdef __TANDEM
+       PROCESS_DELAY_(millisec * 1000LL);
+#else
        poll(NULL, 0, millisec);
+#endif
 }
 
 int xgethostname(char *buf, size_t len)

Regards,
Randall

Quoted 6 lines · Randall S. Becker

I have a platform fix that I'd like to apply once this makes it into the main code. The sleep_millisec uses poll(), which is rather heavy-weight on the NonStop platform. We have a much more efficient sleep function available (with microsecond resolution), which would be more useful unless there is a poll side-effect on which git depends. Would this be acceptable? I could push this at any time really.

We strongly prefer not to contaminate generic part of source with platform specific conditional compilation.

If this were a much larger helper function, it might make sense to perform the compat/*.c dance, but in this case:

* [PATCH 1/2] that implements sleep_millisec() in git-compat-util.h as a static inline function; and then

* [PATCH 2/2] that does the equivalent of your patch below, but in git-compat-util.h

might be the cleanest.

Quoted 23 lines

index bcda41e374..972ecd67bf 100644

wrapper.c +6 -0

@@ -4,6 +4,10 @@
 #include "cache.h"
 #include "config.h"
 
+#ifdef __TANDEM
+#include <cextdecs> /* for PROCESS_DELAY_ */ #endif
+
 static int memory_limit_check(size_t size, int gentle)  {
        static size_t limit = 0;

@@ -650,7 +654,11 @@ void write_file(const char *path, const char
 *fmt, ...)
 
 void sleep_millisec(int millisec)
 {
+#ifdef __TANDEM
+       PROCESS_DELAY_(millisec * 1000LL); #else
        poll(NULL, 0, millisec);
+#endif
 }
 

Quoted 1 line

int xgethostname(char *buf, size_t len)

I just chatted with my team and we think that sticking with the existing poll call is probably better in the long term. We are planning to try to get git to work using PUT threads - but that is a longer project for a whole slew of reasons. It involves pulling all or most of the FLOSS stuff out, or making that configurable to use FLOSS when not using threads and not using FLOSS when using threads. It might be useful, however, to use usleep() instead of poll(NULL) when threading is used on most platforms as it is a more effective way of context switching between threads than select().