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Re: [PATCH 10/23] files_ref_store: put the packed files lock directly in this struct

From
Jeff King <peff@peff.net>
Date
May 17, 2017, 13:17 UTC
Message-ID
<20170517131753.rditx62clmkrdmeq@sigill.intra.peff.net>
In-Reply-To
<dd7637060bac1a27e03563edc82649812dcf897c.1495014840.git.mhagger@alum.mit.edu>
On Wed, May 17, 2017 at 02:05:33PM +0200, Michael Haggerty wrote:
Show 7 quoted lines
> Instead of using a global `lock_file` instance for the main
> "packed-refs" file and using a pointer in `files_ref_store` to keep
> track of whether it is locked, embed the `lock_file` instance directly
> in the `files_ref_store` struct and use the new
> `is_lock_file_locked()` function to keep track of whether it is
> locked. This keeps related data together and makes the main reference
> store less of a special case.

This made me wonder how we handle the locking for ref_stores besides the main one (e.g., for submodules). The lockfile structs have to remain valid for the length of the program. Previously those stores could have xcalloc()'d a lockfile and just leaked it. Now they'll need to xcalloc() and leak their whole structs.

I suspect the answer is "we don't ever lock anything except the main ref store because that is the only one we write to", so it doesn't matter anyway.

-Peff
Previous: Michael HaggertyNext: Michael Haggerty
Message 31 of 73 in “Prepare to separate out a packed_ref_store”
  1. 00/23 Prepare to separate out a packed_ref_storeMichael Haggerty, May 17, 2017
  2. 01/23 t3600: clean up permissions test properlyMichael Haggerty, May 17, 2017
  3. Jeff KingMay 17, 2017
  4. Michael HaggertyMay 17, 2017
  5. Junio C HamanoMay 18, 2017
  6. Michael HaggertyMay 19, 2017
  7. 02/23 refs.h: clarify docstring for the ref_transaction_update()-related fnsMichael Haggerty, May 17, 2017
  8. Stefan BellerMay 17, 2017
  9. Junio C HamanoMay 18, 2017
  10. 03/23 ref_iterator_begin_fn(): fix docstringMichael Haggerty, May 17, 2017
  11. 05/23 refs_ref_iterator_begin(): don't check prefixes redundantlyMichael Haggerty, May 17, 2017
  12. Jeff KingMay 17, 2017
  13. Michael HaggertyMay 17, 2017
  14. 07/23 ref_store: take `logmsg` parameter when deleting referencesMichael Haggerty, May 17, 2017
  15. Jeff KingMay 17, 2017
  16. Michael HaggertyMay 17, 2017
  17. Jeff KingMay 17, 2017
  18. 04/23 prefix_ref_iterator: don't trim too muchMichael Haggerty, May 17, 2017
  19. Jeff KingMay 17, 2017
  20. Michael HaggertyMay 17, 2017
  21. Jeff KingMay 17, 2017
  22. Junio C HamanoMay 18, 2017
  23. Michael HaggertyMay 18, 2017
  24. 09/23 files-backend: move `lock` member to `files_ref_store`Michael Haggerty, May 17, 2017
  25. Jeff KingMay 17, 2017
  26. Michael HaggertyMay 17, 2017
  27. 06/23 refs: use `size_t` indexes when iterating over ref transaction updatesMichael Haggerty, May 17, 2017
  28. Stefan BellerMay 17, 2017
  29. Michael HaggertyMay 18, 2017
  30. 10/23 files_ref_store: put the packed files lock directly in this structMichael Haggerty, May 17, 2017
  31. Jeff KingMay 17, 2017
  32. Michael HaggertyMay 17, 2017
  33. Stefan BellerMay 17, 2017
  34. Brandon WilliamsMay 18, 2017
  35. Michael HaggertyMay 19, 2017
  36. Brandon WilliamsMay 18, 2017
  37. Jeff KingMay 18, 2017
  38. Brandon WilliamsMay 18, 2017
  39. 12/23 ref_transaction_commit(): break into multiple functionsMichael Haggerty, May 17, 2017
  40. Stefan BellerMay 17, 2017
  41. Michael HaggertyMay 19, 2017
  42. 16/23 should_pack_ref(): new function, extracted from `files_pack_refs()`Michael Haggerty, May 17, 2017
  43. 17/23 get_packed_ref_cache(): assume "packed-refs" won't change while lockedMichael Haggerty, May 17, 2017
  44. Stefan BellerMay 17, 2017
  45. Jeff KingMay 18, 2017
  46. Stefan BellerMay 18, 2017
  47. 18/23 read_packed_refs(): do more of the work of reading packed refsMichael Haggerty, May 17, 2017
  48. 19/23 read_packed_refs(): report unexpected fopen() failuresMichael Haggerty, May 17, 2017
  49. Jeff KingMay 17, 2017
  50. Michael HaggertyMay 17, 2017
  51. Junio C HamanoMay 18, 2017
  52. Jeff KingMay 18, 2017
  53. 15/23 ref_update_reject_duplicates(): add a sanity checkMichael Haggerty, May 17, 2017
  54. 20/23 refs_ref_iterator_begin(): handle `GIT_REF_PARANOIA`Michael Haggerty, May 17, 2017
  55. Jeff KingMay 17, 2017
  56. 22/23 ref-filter: limit traversal to prefixMichael Haggerty, May 17, 2017
  57. Jeff KingMay 17, 2017
  58. Michael HaggertyMay 19, 2017
  59. 14/23 ref_update_reject_duplicates(): use `size_t` rather than `int`Michael Haggerty, May 17, 2017
  60. 23/23 cache_ref_iterator_begin(): avoid priming unneeded directoriesMichael Haggerty, May 17, 2017
  61. 21/23 create_ref_entry(): remove `check_name` optionMichael Haggerty, May 17, 2017
  62. 08/23 lockfile: add a new method, is_lock_file_locked()Michael Haggerty, May 17, 2017
  63. Jeff KingMay 17, 2017
  64. 11/23 files_transaction_cleanup(): new helper functionMichael Haggerty, May 17, 2017
  65. Jeff KingMay 17, 2017
  66. Michael HaggertyMay 19, 2017
  67. Stefan BellerMay 17, 2017
  68. Michael HaggertyMay 19, 2017
  69. 13/23 ref_update_reject_duplicates(): expose function to whole refs moduleMichael Haggerty, May 17, 2017
  70. Jeff KingMay 17, 2017
  71. Stefan BellerMay 17, 2017
  72. Johannes SixtMay 18, 2017
  73. Jeff KingMay 18, 2017

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